• 专利附录
  • 专利说明
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    • 专利摘要:
    improvement of solvent resistance of epoxy resins reinforced with polyether sulfone. the solvent resistance of epoxy resins reinforced with polyether sulfone is improved by using low molecular weight polyether sulfone. the resulting thermoplastic reinforced epoxy resins are useful for the production of prepregs for aerospace applications.
    公开号:BR112013005904B1
    申请号:R112013005904
    申请日:2011-10-06
    公开日:2020-02-04
    发明作者:Wang Yen-Seine
    申请人:Hexcel Corp；
    IPC主号:
    专利说明:

    "EPOXY RESIN TENACIFIED WITH UNCURED THERMOPLASTIC, COMPOSITE EPOXY MATERIAL TENACIFIED WITH UNCURED THERMOPLASTIC, COMPOSITE PART AND METHOD FOR MANUFACTURING A PRE-IMPREGNATED"
    Background of the invention
    1. Field of the invention [001] The current invention refers generally to epoxy resins that are toughened with thermoplastic materials. Such tenacified resins are used for the production of high performance composite parts. More particularly, the current invention is directed to increasing the resistance of such thermoplastic epoxy resins to cracks and breaks that can occur when cured epoxy resins are exposed to solvents, such as methyl ethyl ketone (MEK).
    2. Description of the Related Art [002] Composite materials typically consist of a matrix of resin and reinforcement fibers as the two main constituents. Resin matrices that contain one or more epoxy resins as the main ingredient are widely used. Composite materials are often required to work in specific environments, such as in the aerospace field or where the physical limits and characteristics of composite parts are of critical importance.
    [003] The pre-impregnated composite material (pre-impregnated) is widely used in the manufacture of composite parts. Prepreg is a combination of uncured resin and fiber reinforcement, which is in a form that is ready for molding and curing in the production of the final composite part. When pre-impregnating the fiber or resin reinforcement, the manufacturer can carefully control the quantity and location of the resin that is impregnated in the fiber network and ensure that the resin is distributed in the network as required. It is well known that the relative amount of fibers and resin in a composite part and the distribution of the resin within the
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    2/31 fiber net has a great effect on the structural properties of the part. Prepreg is a preferred material for use in the manufacture of load-bearing or structural parts, and especially in aerospace structural parts, such as wings, fuselages, partitions and control surfaces. It is important that these parts have sufficient strength, damage tolerance, toughness against interlaminar fracture and other requirements that are routinely established for such parts.
    [004] Fiber reinforcements that are commonly used in aerospace prepregs are multi-directional woven fabrics or unidirectional tapes that contain fibers that extend in parallel with each other. The fibers are typically in the form of bundles of numerous individual fibers or filaments that are referred to as tows. The fibers or tows can also be cut and randomly oriented in the resin to form a non-woven blanket. These various fiber reinforcement configurations are impregnated with a carefully controlled amount of uncured resin. The resulting prepreg is typically placed between protective layers and is rolled up for storage or transportation to the manufacturing facility.
    [005] The prepreg may also be in the form of short segments of cut unidirectional tape that are randomly oriented to form a nonwoven blanket of cut unidirectional tape. This type of prepreg is referred to as an almost isotropic cut prepreg. The almost isotropic cut prepreg is similar to the more traditional pre-impregnated nonwoven fiber mat, except that the short lengths of cut unidirectional tape (“splinters”) are randomly oriented on the mat instead of the cut fibers.
    [006] The tensile strength of a cured composite material is largely dictated by the individual properties of the reinforcement fiber and matrix resin, as well as by the interaction between these two components. In addition, the fiber-resin volumetric ratio is an important factor. Cured composites that are under stress
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    3/31 tend to show failures through a mechanism of accumulated damage arising from multiple breaks by tension of the individual fiber filaments located in the reinforcement tows. When the stress levels in the resin adjacent to the ends of the broken filaments become too large, the entire composite may fail. Therefore, the strength of the fiber, the strength of the resin matrix, and the efficiency of stress dissipation in the vicinity of the ends of the broken filaments, all contribute to the strength of a cured composite material.
    [007] In many applications it is desirable to maximize the tensile strength property of the cured composite material. However, attempts to maximize tensile strength can often result in negative effects on other desired properties, such as compression performance, damage tolerance and resistance to solvent attacks. In addition, attempts to maximize tensile strength can have unpredictable effects on the viscosity, adhesion and service life of the resin matrix.
    [008] The viscosity of the uncured resin is an important factor that must be taken into account when producing a prepreg. The viscosity of the resin must be low enough to ensure that the resin components can be mixed thoroughly and then heavily impregnated in the reinforcement fibers. The viscosity of the resin must also be high enough to ensure that the resin does not drain to any substantial degree during storage or application of the prepreg. Resins that do not have viscosities that meet these basic requirements cannot be used for the production of prepregs. In any attempt to increase the strength and / or damage tolerance of a cured composite material, it is important that the viscosity of the uncured resin remains within acceptable limits.
    [009] The adhesion or adhesion of the uncured prepreg is referred to as
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    4/31 increase as grip. The adhesion of the uncured prepreg is an important consideration during application and molding operations. The prepreg with little or no adhesion is difficult to form laminates that can be molded to produce composite parts. In contrast, the pre-impregnated with too much adhesion can be difficult to manipulate and also difficult to be placed inside the mold. It is desirable that the prepreg has the appropriate amount of adhesion to ensure easy handling and good lamination / molding characteristics. In an attempt to increase the strength and / or damage tolerance of a given cured composite material it is important that the adhesion of the uncured prepreg remains within acceptable limits to ensure proper handling and molding of the prepreg.
    [0010] The useful life of the prepreg is the period of time that the prepreg can be exposed to environmental conditions before being exposed to an unacceptable degree of cure. The useful life of the prepreg can vary greatly, depending on several factors, but it is mainly controlled by the formulation of the resin that is used. The life of the prepreg must be long enough to allow normal handling in application and molding operations without the prepreg being exposed to unacceptable levels of curing. In any attempt to increase the resistance and / or damage tolerance of a given cured composite material, it is important that the service life lasts as long as possible to allow sufficient time for the processing, handling and application of the prepreg before the cure.
    [0011] A common method of increasing the tensile performance of the compound is to change the fiber surface to loosen the bond strength between the matrix and the fiber. This can be achieved by reducing the amount of electro-oxidative treatment of the fiber surface after graphitization. The reduction of the strength of the matrix-fiber bond introduces a mechanism for the dissipation of traction at the
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    5/31 exposed filamentities by weakening the interfacial connection. This weakening of the interfacial bond produces an increase in the amount of tensile damage that a part of the compound can withstand before failing under tension.
    [0012] Alternatively, the application of a covering or coating on the fiber can reduce the resistance between the resin and the fiber. This strategy is well known in fiberglass compounds, but it can also be applied to compounds reinforced with carbon fibers. Using these strategies, it is possible to obtain significant increases in tensile strength. However, the improvements are accompanied by a reduction in properties, such as compressive strength after impact (CAI), which requires a high bond strength between the resin matrix and the fibers.
    [0013] Another method of increasing the traction performance of the compound and resistance to damage is to include one or more thermoplastic materials in the epoxy resin matrix. A variety of different thermoplastic materials have been used in a variety of different ways to toughen epoxy resins. Thermoplastics have been used to toughen epoxy resins and include polyether sulfone (PES), polyether imide (PEI), polyamide imide (PAI) and polyamide (PA). For example, see United States patent number 7,754,322.
    [0014] Multiple layers of prepregs are commonly used to form composite parts for structural applications that have a laminated structure. The delamination of such composite parts is an important failure mode. Delamination occurs when two layers detach from each other. Important design limitation factors include both the energy required to initiate a delamination and the energy required to propagate it. The initiation and growth of a delamination is often determined by examining Mode I and Mode II fracture toughness. The usual fracture toughness
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    6/31 is measured using composite materials that have a unidirectional fiber orientation. The interlaminar fracture toughness of a composite material is quantified using the G1c (Double Cantilever Beam) and G2c (End Notch Flex) tests. In Mode I, the failure of the previously broken laminate is controlled by the detachment forces and in Mode II the fracture is propagated by the tensile forces. G2c interlaminar fracture toughness is related to CAI. Pre-impregnated materials that have high damage tolerances also tend to have high CAI and G2c values.
    [0015] The cured prepreg must also be resistant to attack by solvents and other chemicals to which the cured composite part can be exposed. A common test for determining the interactive effects between stress and solvent on cured resins is to pull a cured resin specimen by folding the specimen and exposing the drawn specimen to a particular solvent or other chemical for a period of time. , which is typically on the order of a few days or more. The specimen is checked for tensile breaks and / or cracks at various times during the test period. Specimens are typically pulled by doubling from 0% to about 2%. The tension varies in proportion to the length of the specimen's arc, which is characteristic of a clothoid curve (spiral). The test apparatus used to induce the clothoid curve in the specimen is known as a clothoid stress tool. The use of a clothoid strain tool allows a single test specimen to be folded to produce stresses across the entire test range.
    [0016] Resin specimens are considered to be highly resistant to attack by a given solvent if they do not show any break when subjected to testing at a maximum stress of 2% on a clothoid stress tool and exposed to the solvent for seven days in the room temperature. To be suitable for use in aerospace applications, resins
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    7/31 cured epoxies must be highly resistant to attacks by solvents to which the resin may be exposed. It is important that the measures taken to strengthen and / or toughen an epoxy resin, inadvertently do not reduce the resistance of the resins to attacks by solvents.
    [0017] Although several existing prepregs are well suited for their intended use in the production of composite parts that are resistant and tolerant to damage, there is still a continuing need to produce prepregs that can be used for the production of composite parts for structural applications that have high levels of resistance (eg, compressive strength), high damage tolerance (CAI) and interlaminar fracture toughness (G1c and G2c) and which have a high resistance to attack by solvents.
    Summary of the invention [0018] According to the current invention, uncured resins are produced which are suitable for use in aerospace applications where high levels of resistance, damage tolerance and interlaminar toughness are required. The invention is applicable to multifunctional epoxy resins that include polyether sulfone (PES) alone or in combination with other thermoplastic agents of tenacification. The invention is based, at least in part, on the discovery that low molecular weight PES, when used as a thermoplastic tenacifier, causes a significant increase in the ability of such thermoplastic tenacified epoxy resins to withstand solvent attack.
    [0019] The current invention relates to uncured resins that include an epoxy resin component made from a difunctional epoxy resin, trifunctional epoxy resin and / or tetrafunctional epoxy resin. The uncured resin further includes a thermoplastic component that includes low molecular weight PES, alone or in combination with one or more other thermoplastic tenacifiers. The invention also relates to uncured resins in combination with a curing component
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    8/31 and / or fiber reinforcement, as well as cured combinations of resin and fiber reinforcement that are suitable for use at least in part of an aircraft's primary structure.
    [0020] Prepregs and methods for the production of prepregs using multifunctional epoxy resins that are toughened with low molecular weight PES are also part of the current invention. The prepreg is suitable for use in the manufacture of cured composite parts that are highly resistant to solvent attack and that are otherwise suitable for use at least in part of an aircraft's primary structure.
    [0021] The characteristics described above and many others and complementary advantages of the current invention will be better understood by reference to the following detailed description, when considered together with the attached drawings.
    Brief description of the drawings [0022] Figure 1 is a perspective view of an aircraft, which details the aircraft's main example structures that can be made using composite materials according to the current invention.
    [0023] Figure 2 is a partial view of a helicopter rotor blade, which details example main structures of the aircraft that can be made using composite materials according to the current invention.
    Detailed description of the invention [0024] The matrix cured resin compositions according to the current invention can be used in a wide variety of situations where epoxy resin toughened with thermoplastic is desired. Although uncured epoxy resin compositions can be used alone, the compositions are generally combined with a fiber support to form composite materials. The composite materials may be in the form of a pre-impregnated, pre-impregnated
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    9/31 partially cured or a final piece completely cured. The term uncured when used here in relation to a prepreg, matrix resin or composite material, is intended to cover items that may have undergone some curing, but that have been completely cured to form the final composite part or structure.
    [0025] Although composite materials can be used for any intended purpose, they are preferably used in aerospace vehicles, and are especially preferred for use in civil and military aircraft. For example, composite materials could be used for the production of non-main (secondary) aircraft structures. However, the preferred use of the composite material is for structural applications, such as main aircraft structures. The main structures or parts of aircraft are those rotating or fixed elements of the aircraft's wings that are subjected to significant stress during the flight and that are essential for the aircraft to keep the flight under control. Composite materials can also be used for other structural applications to produce load-bearing parts and structures in general.
    [0026] Figure 1 details an aircraft with 10 fixed wings and includes a number of structures and main parts of the aircraft that could be made using composite materials according to the current invention. The main example parts or structures include the wing 12, the fuselage 14 and the rear part assembly 16. The wing 12 includes a number of example main parts of the aircraft, such as the "ailerons" 18, rudder 20, wings slats 22, “spoilers” 24, “trailing edge” 26 and trailing edge flaps ”28. The rear part 16 also includes a number of example main parts, such as the rudder 30, fin 32, and horizontal stabilizer 34, elevators 36 and rear 38. Figure 2 details the outer parts of the end of a helicopter rotor blade 40 that includes a spar 42 and an outer surface 44 as the main structures of the aircraft.
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    10/31
    Other examples of the aircraft's main structures include wing spars, and a variety of flanges, clips and connectors that connect the main parts with each other to form the main structures.
    [0027] The uncured resin and pre-impregnated (pre-impregnated) composite materials of the current invention may be used as a substitute for an existing uncured and / or pre-impregnated resin that is being used to form composite parts in the aerospace industry and in any other structural applications where high resistance and damage tolerance are required. The invention involves replacing the resin formulations of the current invention in place of existing resins being used to produce prepregs. Accordingly, the resin formulations of the current invention are suitable for use in any of the conventional prepreg production and curing processes that are suitable for thermoplastic epoxy resins.
    [0028] The pre-impregnated composite materials according to the current invention are composed of reinforcing fibers and an uncured resin matrix. Reinforcement fibers can have any conventional fiber configuration that is used in the prepreg industry. The uncured resin matrix includes an epoxy resin component that includes difunctional, tri-functional and tetrafunctional aromatic epoxy resins alone or in combination. Epoxy resin components that are made by a combination of trifunctional and tetrafunctional epoxy resins are preferred. The resin matrix further includes a thermoplastic component that is composed of low molecular weight PES, alone or in combination with one or more thermoplastic agents. A curative component that contains one or more curing agents can be added directly to the resin formulation or it can be added immediately before or during the curing process. For example, the curative component may be located inside or adjacent to the reinforcement fibers in a separate location from the epoxy resin for the mixture, to form the matrix
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    11/31 resin during the curing / molding process.
    [0029] As will be discussed in detail below, a feature of the current invention is the discovery that the use of low molecular weight PES in the thermoplastic component produces cured composite materials that are highly resistant to attack by solvents, such as MEK.
    [0030] The epoxy resin component, preferably, consists of one or more tri-functional epoxy resins and / or tetrafunctional epoxy resins. A combination of trifunctional and tetrafunctional epoxy resins is preferred. Multifunctional epoxy resins can be saturated, unsaturated, cycloaliphatic, alicyclic or heterocyclic. Suitable multifunctional epoxy resins, for example, include those based on: phenol and cresol epoxy novolacs, glycidyl ethers of phenol and aldehyde derivatives; glycidyl ethers of dialysate diols; diglycidyl ether; diglycidyl ether diethylene glycol; aromatic epoxy resins; dialytic triglycidyl ethers, aliphatic poly-glycidyl ethers; epoxidated olefins, brominated resins; aromatic glycidyl amines; glycidyl imidines and heterocyclic amides; glycidyl ethers; fluoridated epoxy resins or any other combination thereof. The epoxy resin component can consist of 40 to 65% by weight of the matrix resin.
    [0031] A trifunctional epoxy resin will be understood to have the three epoxy groups substituted directly or indirectly in an orientation towards or meta in the phenyl ring in the basic structure of the compound. Goal orientation is preferred. A tetrafunctional epoxy resin will be understood to have the four epoxy groups substituted directly or indirectly in a meta orientation or to the phenyl ring in the basic structure of the compound.
    [0032] The phenyl ring may additionally be substituted by other suitable non-epoxy substituent groups. Suitable substituent groups, for example, include hydrogen, hydroxyl radicals, alkyl, alkenyl, alkynyl, alkoxy, aryl, aryloxy, aralkyloxy, aralkyl, halo, nitro, or cyano. Substituent groups are not
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    Suitable epoxies may be attached to the phenyl ring in the para or ortho positions, or be attached in the meta position not occupied by an epoxy group. Suitable tetrafunctional epoxy resins include N ', N', N, N-tetraglycidyl-m-xylenediamine (commercially available from Mitsubishi Gas Chemical Company (Chiyoda-Ku, Tokyo, Japan) under the name Tetrad-X), and Erisys GA-240 (from CVC Chemicals, Morristown, New Jersey). Suitable tri-functional epoxy resins, for example, include those based on: phenol and cresol epoxy novolacs; glycidyl ethers of phenolaldehyde derivatives; aromatic epoxy resins, triglycidyl ethers; polyglycidyl aliphatic ethers; and epoxidized olefins; and brominated resins, aromatic glycidyl amines and glycidyl ethers; glycidyl imidines and heterocyclic amides; glycidyl ethers; fluoridated epoxy resins or any combination thereof.
    [0033] A preferred trifunctional epoxy resin is triglycidyl meta-aminophenol. Triglycidyl meta-aminophenol is commercially available from Huntsman Advanced Materials (Monthey, Switzerland) under the brands Araldite MY0600 or MY0610 from Sumitomo Chemical Co. (Osaka, Japan) under the brand name ELM-120.
    [0034] Additional examples of suitable multifunctional epoxy resins include N, N, N ', N'-tetraglycidyl-4,4'-diaminophenyl methane (TGDDM commercially available as Araldite MY720 and MY721 from Huntsman Advanced Materials (Monthey, Switzerland), or ELM 434 from Sumitomo), para-aminophenol triglycidyl ether (commercially available as Huntsman Advanced Materials Araldite MY0500 or MY 0510), epoxy resins based on dicyclopentadiene, such as Tactix 556 (commercially available from Huntsman Advanced Materials), tris- ( hydroxylphenyl) and methane-based epoxy resin such as Tactix 742 (commercially available from Huntsman Advanced Materials). Other suitable multifunctional epoxy resins include DEN 438 (from Dow Chemicals, Midland, MI), DEN 439 (from Dow Chemicals), Araldite ECN 1273 (from Huntsman Advanced Materials), and Araldite ECN 1299 (from Huntsman Advanced Materials). TGDDM (MY720 or MY721) is a preferred tetrafunctional epoxy.
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    13/31 [0035] The epoxy component may also include difunctional epoxy resins, such as Bisphenol-A (Bis-A) or Bisphenol-F (Bis-F) epoxy resin. The example BisA epoxy resin is commercially available as Araldite GY6010 (Huntsman Advanced Materials) or DER 331, which is available from Dow Chemical Company (Midland, MI). The example Bis-F epoxy resin is commercially available as Araldite GY281 and GY285 (Huntsman Advanced Materials). The amount of Bis-A or Bis-F epoxy resin present in the epoxy resin component can be varied. It is preferred that no more than 20% by weight of the epoxy resin component is difunctional epoxy resin. The epoxy resin component preferably contains more trifunctional and tetra functional epoxy resin with the preferred weight ratio between trifunctional and tetrafunctional epoxy resins ranging from 2.0: 1 to 2.4: 1.
    [0036] It is preferable that the resin matrix includes little, if any, difunctional epoxy resin. The resin matrix preferably included 20 to 40% by weight of trifunctional epoxy resin and 10 to 30% by weight of tetrafunctional epoxy resin. It is more preferable that the resin matrix contains 30 to 40% by weight of trifunctional epoxy resin and 10 to 20% by weight of tetrafunctional epoxy resin. A combination of triglycidyl meta-aminophenol (MY0600 or MY0610) with TGDDM (MY720 or MY721) is especially preferred. It should be noted that the weight percentages of the various ingredients listed here that are based on the weight of the resin matrix should be calculated based on the weight of a resin matrix that includes the epoxy resin component, the thermoplastic component, curing agent and additives, if any.
    [0037] As a feature of the invention, the uncured resin matrix includes a thermoplastic component that is composed of low molecular weight PES alone or in combination with one or more thermoplastic materials that can be soluble or insoluble in the epoxy resin. It is preferred that the thermoplastic component includes a combination of soluble and insoluble thermoplastic materials.
    [0038] Low molecular weight PES as used here means a PES
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    14/31 which has a molecular weight (g / mol) between 10,000 and 30,000. Preferably, the low molecular weight PES will have a molecular weight of 15,000 to 25,000. A low molecular weight PES having a molecular weight of about 21,000 is most preferred. Low molecular weight PES is commercially available from several sources. For example, PES having a molecular weight of about 21,000 g / mol is available from Solvay Advanced Polymers (Greenville, SC) under the brand name VW-10700RP. The invention involves improving the solvent resistance of a thermoplastic epoxy resin by replacing the low molecular weight PES in place of the high molecular weight PES that is conventionally used in thermoplastic components. Standard high molecular weight PES is sold under the Sumikaexcel 5003P brand, which is commercially available from Sumitomo Chemicals. Alternatives to the 5003P are the Solvay 105RP or VW-10200RP polyether sulfone or the non-hydroxyl-terminated grades like Solvay 1054P (Solvay Advanced Polymers Greenville, SC). The molecular weight of the 5003P and VW-10200RP is around 46,500 g / mol. For the purposes of this specification, high molecular weight PES is any PES that has a molecular weight greater than 30,000 g / mol.
    [0039] For any thermoplastic component mentioned, it is preferable that substantially the entire amount of PES (at least 95% by weight) is in the form of low molecular weight PES. However, it is possible to replace only a portion of the higher molecular weight PES with low molecular weight PES, provided that the desired increase in solvent resistance is obtained. It is preferable that at least 50% by weight of the PES is in the form of low molecular weight PES. It is more preferable that at least 80% by weight of the PES present in the thermoplastic component is low molecular weight PES.
    [0040] PES is a thermoplastic that is considered to be soluble in epoxy resins. Other example soluble epoxy resins that can be used in combination with PES include polyetherimide (PEI) and polysulfone (PS). Typically, the
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    15/31 thermoplastic polymer is added to the resin mixture as particles that are dissolved in the resin mixture by heating before adding the insoluble particles and the curing agent. As soon as the thermoplastic polymer is substantially dissolved in the resin precursor of the hot matrix (ie, the mixture of epoxy resins), the precursor is cooled and the remaining ingredients (curing agent, if included, insoluble thermoplastics and / or any other additives) are added.
    [0041] It is preferable that the uncured resin matrix includes 10 to 20% by weight of soluble thermoplastic material. Most preferred is an uncured resin matrix containing 12 to 18% by weight of soluble thermoplastic material. More preferably, a resin matrix containing 13 to 15% by weight of thermoplastic material. It is preferred that the majority of the soluble thermoplastic (at least 80% by weight) of the thermoplastic component is PES and that substantially the entire amount of PES is in the form of low molecular weight PES. A resin matrix is most preferred where substantially all (or at least 95% by weight) of the thermoplastic soluble in the thermoplastic component is low molecular weight PES.
    [0042] The thermoplastic component preferably also includes insoluble thermoplastic particles. These particles do not dissolve during the curing process and remain within the zones of intermediate layers of the cured composite material. The amount of insoluble particles in the uncured resin matrix is preferably 5 to 20% by weight. Most preferred are resin matrices containing 6 to 18% by weight of insoluble particles. Most preferred are resin matrices containing 8 to 12% by weight of insoluble particles.
    [0043] Examples of suitable thermoplastic particles include polyamideimide (PAI) particles and polyamide (PA) particles. Thermoplastic particles have glass transition temperatures (Tg) that are above room temperature.
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    16/31 (22 ° C).
    [0044] Polyamide particles contain a variety of grades that have different melting temperature ranges, depending on the specific polyamide and the molecular weight of the polyamide. The polyamide particles according to the current invention have melting temperature ranges above 170 ° C and below 240 ° C. It is preferable that the polyamide particles have a Young's modulus between 200 and 400 ksi, with a modulus of about 300 ksi being especially preferred.
    [0045] Suitable polyamide particles contain polyamide 6 (caprolactam -PA6) as the main ingredient, but may also contain small amounts of polyamide 12 (laurolactam - PA12) and / or polyamide 11. The particles must have particle sizes below 100 microns. It is preferable that the particle size range is 5 to 60 microns, and more preferably, 10 to 30 microns. It is preferable that the average particle size is around 20 microns. The particles must be substantially spherical. The particles can be made by anionic polymerization according to PCT application WO 2006/051222 through coextrusion, precipitation polymerization, emulsion polymerization or by cryogenic grinding. Suitable polyamide particles are commercially available from Arkema of France under the trade name Orgasol.
    [0046] Orgasol 1002 D NATI is an example of a suitable polyamide particle. Orgasol 1002 D NATI is composed of 100% PA6. Young's modulus of the Orgasol 1002 D NATI particles is around 300 ksi. Particles having a degree of crystallinity equal to 51%, a glass transition temperature (Tg) of 26 ° C, a density of 1.15 (ISO 1183), a molecular weight of 60,200 (g / mol) have a point melting temperature of 217 ° C and an average particle size of 20 microns. Another example of a suitable rigid particle is Orgasol 3202 D Nat 1 which contains particles from the PA6 / PA12 copolymer (80% PA6 and 20% PA12) having a degree of crystallinity equal to 43%, a Tg of 29 ° C, a density of 1.09 (ISO 1183), a
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    17/31 molecular weight of 60,800 (g / mol) and a solution viscosity of 1.01. The particles of the polyamide copolymer Orgasol 3202 D Nat 1 have an average particle size of 20 microns and a melting point of 194 ° C. The amount of PA12 in the copolymer can be increased by more than 20%.
    [0047] It is preferable that the resin matrix includes PA particles and that the amount of PA particles is in the range of 1 to 10% by weight of the total resin matrix. It is more preferable that the amounts of PA particles are in the range of 2 - 8% by weight.
    [0048] Suitable PAI particles are commercially available as TORLON 4000 T or TORLON 4000 TF from Solvay Advanced Polymers (Alpharetta, GA). The preferred average particle size range for PAI particles is 8 microns to 20 microns. PAI particles have a Young's modulus of about 600 ksi. It is preferred that the resin matrix includes PAI particles and that the amount of PAI particles is in the range of 5 to 15% by weight of the total resin matrix. It is more preferable that the amounts of PAI particles are in the range of 4 - 10% by weight. A preferred thermoplastic component includes both PAI and PA particles. Preferred weight ratios between PAI and PA particles range from 2: 1 to 4: 1 with weight ratios between about 2.8: 1 and 3.8: 1 being especially preferred.
    [0049] The uncured resin can also include elastic particles in amounts up to 10% by weight of the resin matrix. Preferred amounts of elastic particles vary from 5 to 9% by weight of the resin matrix. Suitable elastic particles include particles that are composed primarily of polyurethane. The elastic particles preferably contain at least 95% by weight of polyurethane polymer. Other elastic particles that are composed of a high molecular weight elastomer that are insoluble in epoxy can also be used. Young's modulus of elastic particles must be less than 10 ksi. THE
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    18/31
    Tg of the elastic particles must be at room temperature (22 ° C) or less.
    [0050] Polyurethane particles that contain a small amount (less than 5% by weight) of silica are a preferred type of elastic particle. The polyurethane particles that are available from Aston Chemicals (Aylesbury, UK) under the trademark SUNPU-170 are a preferred type of polyurethane particle. SUNPU-170 consists of cross-polymer HDI / trimethylol Hexillactone, and silica. The particles contain about 95 to 99% by weight of urethane polymer and 1 to 5% by weight of silica. The particles are microspheres with a diameter range of 5 microns to 20 microns. Suitable polyurethane particles are also available from Kobo Products (South Plainfield, NJ) under the trademark BPD-500, BP-500T and BP-500W. These particles are also made up of the cross polymer of HDI / Trimethylol hexillactone and silica. The particles are also microspheres ranging in size from 10 microns to 15 microns. The BPD-500 microspheres contain 1 to 3% by weight of silica and 97 to 99% by weight of polyurethane.
    [0051] Particle sizes and relative amounts of insoluble thermoplastic particles and elastic particles are chosen so that not only the desired levels of OHC, CAI, G1c and G2c are obtained, but also the viscosity of the epoxy resin composition is achieved. within a range that is suitable for preparing the prepreg. It is preferable that the viscosity of the resin is the same as the viscosity of existing high performance tenacified resins, which are currently used in the aerospace industry for existing high performance reinforced resins that are currently used in the aerospace industry to produce prepregs that include prepregs. -pregnated cut almost isotropic. In order to obtain the desired combination of uncured resin properties and cured compound properties according to the present invention, it is preferred that the thermoplastic component contains at least two different types of insoluble thermoplastic particles in the amounts prescribed herein.
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    19/31 [0052] Using low molecular weight PES in place of the standard higher molecular weight PES, this is also useful for reducing the viscosity of the resin matrix. It has also been found that using low molecular weight PES, this helps to keep the uncured resin viscosity within acceptable limits for the preparation of prepregs. This is especially the case for uncured resins that contain amounts of thermoplastic materials that are close to the highest end of the acceptable range and / or where the elastic particles are included as part of the resin mixture.
    [0053] The amount of curing agent component that is combined with the epoxy resin component and the thermoplastic component is 10 to 45% by weight of the total weight of the epoxy resin matrix. Example curative agents according to the current invention include diciandiamide, methylenedianiline (MDA), m-phenylenediamine (MPDA), 4,4'-methylene bis (diethylaniline), 3,3'-diamino diphenylsulfone (3,3'DDS) , 4,4'-diamino diphenyl sulfone (4,4'-DDS) and 4,4'-Bis (p-aminophenoxy) biphenyl (BAPB). 3,3'-DDS and 4,4'-DDS are preferred curing agents that can be used alone or in combination. It is especially preferable that the curable component is composed substantially (at least 95% by weight) of 3,3'-DDS in amounts ranging from 15.0 to 25.0% by weight of the matrix resin.
    [0054] BAPD is also a preferred curing agent. The amount of BAPD included in the resin matrix will depend on the amount and type of epoxies present. The amount of BAPD must be sufficient to ensure complete curing of the uncured resin. This amount can be calculated based on the functionality and the amount of each epoxy resin in the formulation. The amount of BAPD required to produce the complete cure will be between 15 and 45% by weight of the total uncured amount. Preferred amounts of BAPD are between 30 and 40% by weight of the matrix resin.
    [0055] One or more cure accelerators may be included in the matrix of
    Petition 870190116181, of 11/11/2019, p. 32/49
    20/31 epoxy resin as long as the solvent resistance of the cured resin is not adversely affected. In addition, the amount of accelerator used should not adversely affect other properties of the uncured resin, such as viscosity and adhesion, to make it difficult to use the resin in the formation of the prepreg. Suitable accelerators are any of the urone compounds that are commonly used. Specific examples of accelerators that can be used alone or in combination, include N, N-dimethyl, N'-3,4-dichlorphenyl urea (Diuron), N'-3-chlorophenyl urea (Monuron), and preferably, N, N- (4-methyl-m-phenylene bis [N ', N'dimethylurea] (eg Dyhard UR500 available from Degussa). The amount of accelerator present in the epoxy resin composition, if any, must be kept below 2 % by weight of the total composition The use of a catalyst is not preferable.
    [0056] The uncured resin may also include additional ingredients, such as performance enhancing or modifying agents and additional thermoplastic polymers, as long as they do not adversely affect the pre-impregnation viscosity, adhesion and life or strength , damage tolerance and solvent resistance of the cured compound part. Performance enhancing or modifying agents, for example, may be chosen from flexibilizers, additional thermoplastic polymers, accelerators, shell and core rubbers, flame retardants, wetting agents, pigments / dyes, UV absorbers, antifungal compounds, fillers, conductive particles, and viscosity modifiers. Suitable additional thermoplastic polymers include any of the following, alone or in combination: polyetheretherone (PEES), polyphenylsulfone, polyimide, aramid, polyester, polyketone, polyetheretherketone (PEEK), polyurea, polyaryether, polyarylsulfides, polycarbonates, polyphenylene oxide (polyphenylene oxide) and modified PPO.
    [0057] Suitable fillers include, for example, any of the following, alone or in combination: silicas, aluminas, titania, glass, carbonate
    Petition 870190116181, of 11/11/2019, p. 33/49
    21/31 calcium and calcium oxide.
    [0058] Suitable conductive particles, for example, include any of the following, alone or in combination: silver, gold, copper, aluminum, nickel, conductive carbon grades, buckminsterfullerene, carbon particles, carbon nano-tubes and carbon nanofibers. Metal-coated fillers, for example, nickel-coated carbon particles and silver-coated copper particles, may also be used.
    [0059] The uncured resin matrix may, if desired, include an additional non-epoxy thermoset polymeric resin. As soon as it is cured, a thermoset resin is not suitable for melting and remolding. Non-epoxy thermosetting materials suitable for the current invention include, but are not limited to, phenol formaldehyde, urea-formaldehyde, 1,3,5-triazine-2,4,6-triamine (Melamine), bismaleimide resins, vinyl ester resins, benzoxazine resins, phenolic resins, polyesters, cyanate ester resins, epoxide polymers, or any combination thereof. The thermoset resin is preferably chosen from epoxide resins, cyanate ester resins, bismaleimide, vinyl ester, benzoxazine and phenolic resins. If desired, the matrix may include other suitable resins containing phenolic groups, such as resorcinol based resins, and resins formed by cationic polymerization, such as DCPD - phenol copolymers. Still additional suitable resins are melamine-formaldehyde resins, and urea-formaldehyde resins.
    [0060] The uncured resin matrix is made according to the standard processing for prepregs. In general, the various epoxy resins are mixed at room temperature to form a resin mixture in which the thermoplastic component is added. This mixture is then heated to a temperature above the melting point of the thermoplastic in the thermoplastic component for a time sufficient to substantially melt the thermoplastic. The mixture is then cooled
    Petition 870190116181, of 11/11/2019, p. 34/49
    22/31 to room temperature or less and insoluble thermoplastic particles, the curative curing component and other additives, if any, are then mixed into the resin to form a final uncured resin matrix that is impregnated in the fiber reinforcement. As mentioned earlier, in some applications, the curative component is stored separately from the rest of the components until the molding / curing process.
    [0061] The uncured resin matrix is applied to the fiber reinforcement according to any of the known techniques of prepreg production. The fiber reinforcement may be totally or partially impregnated with the uncured resin. In an alternative embodiment, the uncured resin may be applied to the fiber reinforcement as a film or separate layer, which is close to, and is in contact with, the fiber reinforcement, but does not substantially impregnate the fiber reinforcement. The prepreg is typically covered on both sides with a protective film and is rolled up for storage and shipping at temperatures that are typically kept well below room temperature to prevent premature curing. If desired, any of the pre-impregnated production processes and different storage / dispatch systems can be used.
    [0062] The fiber reinforcement of the prepreg may be chosen from hybrid systems or from mixed fibers that are made up of synthetic or natural fibers, or a combination thereof. The fiber reinforcement can preferably be chosen from any suitable material, such as glass fiber, carbon fibers or aramid (aromatic polyamide). The fiber reinforcement is preferably carbon fiber.
    [0063] Fiber reinforcement may contain broken fibers (i.e., tensile broken) or selectively discontinuous fibers, or continuous fibers. The use of broken or selectively discontinuous fibers may facilitate the application of the composite material before it is fully cured, and improves its ability to be formatted
    Petition 870190116181, of 11/11/2019, p. 35/49
    23/31 do. The fiber reinforcement may be in a woven, non-wavy, non-woven, unidirectional shape, or in the form of a multiaxial textile structure, such as an almost isotropic cut impregnate. The woven shape can be chosen in a flat, silky or diagonal style. The non-wavy and multiaxial shapes may have a number of folds and orientations of the fibers. These styles and shapes are well known in the field of compound reinforcement and are commercially available from several companies, including Hexcel Reinforcements (Villeurbanne, France).
    [0064] The prepreg may be in the form of continuous tapes, pre-impregnated in rolls, fabrics, or with cut lengths (cutting and incision operations can be done anywhere after impregnation). The prepreg may be an adhesive or surface film and additionally it may have a vehicle embedded in various forms, both woven, cut and non-woven. The prepreg may be fully or only partially impregnated, for example, to facilitate the removal of air during curing.
    A preferred example uncured resin matrix includes 30 to 40% by weight of triglycidyl-m-aminophenol (trifunctional epoxy resin); 10 to 20% tetrafunctional para-glycidyl (tetrafunctional epoxy resin); from 10 to 20% by weight of low molecular weight polyether sulfone; from 5 to 15% by weight of polyamide-imide (insoluble thermoplastic particle); from 1 to 5% by weight of polyamide particles (insoluble thermoplastic particle); and from 15 to 25% by weight of 3,3'-DDS (curative component). An alternative preferred embodiment further comprises 5.0 to 9.0% by weight of polyurethane particles.
    An especially preferred uncured resin matrix includes about 32 to 36% by weight of triglycidyl-m-amino phenol (trifunctional epoxy resin); about 14 to 16% of tetrafunctional para-glycidyl amine (tetrafunctional epoxy resin); about 13 to 16% by weight of low molecular weight polyether sulfone (soluble thermoplastic); about 9 to 11% by weight of polyamide-imide (insoluble thermoplastic particle
    Petition 870190116181, of 11/11/2019, p. 36/49
    24/31 speed); about 2 to 4% by weight of polyamide particles (insoluble thermoplastic particle); and about 18 to 20% by weight of 3,3'-DDS (curative component).
    [0067] Another preferred uncured resin matrix includes about 23 to 25% by weight of triglycidyl-m-aminophenol (trifunctional epoxy resin); about 23 to 25% by weight of tetrafunctional para-glycidyl amine (tetrafunctional epoxy resin); and about 16 to 18% by weight of low molecular weight polyether sulfone (soluble thermoplastic); and about 33 to 36% by weight of BAPD (curing component).
    [0068] The prepreg can be molded using any of the standard techniques used for the formation of composite parts. Typically, one or more layers of prepregs that are placed in a suitable mold and are cured to form the final piece of compost. The prepreg of the invention can be fully or partially cured using any suitable temperature, pressure, and weather conditions known in the art. Typically, the prepreg will be cured in an autoclave at temperatures between 160 ° C and 190 ° C. The uncured compound material can also be cured using a method that is chosen from visible UV radiation, microwave radiation, electron beam, gamma radiation, or other suitable thermal or non-thermal radiation.
    [0069] The composite parts made from the improved prepreg of the current invention will be applied in the production of articles, such as numerous primary and secondary aerospace structures (wings, fuselages, airplane body and the like), but will also be useful for other applications high-performance structural components in the automotive, train, naval and energy industries, where high tensile strength, compressive strength, interlaminar fracture toughness and resistance to impact damage are required.
    [0070] It has been discovered that cured resins containing low molecular weight PES according to the current invention are highly resistant to attack by MEK. When pulled and immersed in MEK at room temperature for seven
    Petition 870190116181, of 11/11/2019, p. 37/49
    25/31 days, cured resins show no fracture and show visible cracks only above 1% tensile strength. In view of the high resistance of MEK-cured resins, cured resins are also expected to have high resistance to attack by other ketone-type solvents, such as acetone. Cured resins will also be highly resistant to less aggressive solvents, to which cured resins may be exposed during use, as part of an aircraft. Such potential solvents include hydraulic fluids, jets, gasoline, alcohols and organic solvents.
    [0071] In order for the current invention to be more quickly understood, reference will now be made to the following examples of the invention.
    EXAMPLE 1 [0072] A preferred example resin formulation according to the current invention is shown in TABLE 1. A resin matrix was prepared by mixing the epoxy ingredients at room temperature with low molecular weight polyether sulfone to form a resin mixture that was heated at 130 ° C for 60 minutes to completely dissolve the low molecular weight polyether sulfone. The mixture was cooled to 80 ° C and the rest of the ingredients (polyamide-imide particles, polyamide particles and curing agent) were added and mixed intensively to form an uncured resin.
    TABLE 1
    Quantity (% weight) Ingredient 35.5 Trifunctional meta-glycidyl amine (MY0610) 16.0 Tetrafunctional para-glycidyl amine (MY721) 15.0 Low PM PES (VW-10700RP) 10.8 Polyamide-imide (Torlon 4000TF) 3.2 Polyamide particles (Orgasol 1002 D Nat 1) 19.5 3,3'-diaminodiphenyl sulfone (3,3'-DDS)
    Petition 870190116181, of 11/11/2019, p. 38/49
    26/31 [0073] The uncured resin had a viscosity that was suitable for use in the production of prepregs. When impregnated in the fiber reinforcement, the resulting prepreg will have adhesion and life properties that are acceptable for use in forming molding articles. Examples of prepregs can be prepared by impregnating one or more layers of unidirectional carbon fibers with the resin formulation of TABLE 1. Unidirectional carbon fibers are used to produce a prepreg in which the matrix resin represents 35 % by weight of the total weight of the uncured prepreg, and the weight of the fiber area is around 190 g per square meter (gsm). A variety of prepreg applications can be prepared using standard prepreg manufacturing procedures. Prepregs are cured in an autoclave at 180 ° C for about 2 hours. The resulting composite parts have high strength, damage tolerance properties and toughness to interlaminar fracture which makes them suitable for use on the main structures of the aircraft.
    [0074] A solvent resistance test specimen was prepared using the resin formulation from TABLE 1. The resin was formed as a specimen that was 4.5 inches (11.4 cm) long, 0.5 inches (1.3 cm) wide and 0.63 inches (0.16 cm) thick. The resin was cured in an autoclave at 180 ° C for about 2h to form a cured test specimen. The test specimen was drawn on a standard clothoid test tool to produce stresses ranging from 0% to a maximum of 2%. The strained test specimen was immersed in MEK at room temperature for a period of seven days. After seven days, the test specimen showed cracks only above a 1.29% stressed spot on the test specimen.
    COMPARATIVE EXAMPLE 1 [0075] A comparative resin having the formulation shown in TABLE
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    27/31 was prepared in the same way as in EXAMPLE 1. The resin is the same as the resin in EXAMPLE 1, except that the low molecular weight PES was replaced with high molecular weight PES.
    TABLE 2
    Quantity (% weight) Ingredient 35.5 Trifunctional meta-glycidyl amine (MY0610) 16.0 Tetrafunctional para-glycidyl amine (MY721) 15.0 High PM PES (Sumikaexcel 5003P) 10.8 Polyamide-imide (Torlon 4000TF) 3.2 Polyamide particles (Orgasol 1002 D Nat 1) 19.5 3,3'-diaminodiphenyl sulfone (3,3'-DDS)
    [0076] A specimen for the solvent resistance test was prepared using the resin formulation of TABLE 2. The resin was formed as a specimen that was 4.5 inches (11.4 cm) long, 0.5 inches (1.3 cm) wide and 0.63 inches (0.16 cm) thick. The resin was cured in an autoclave at 180 ° C for about 2h to form a cured test specimen. The test specimen was tensioned in a standard clothoid test tool to produce stresses ranging from 0% to a maximum of 2%. The tensioned test specimen was immersed in MEK at room temperature and fractured within 10 seconds.
    EXAMPLE 2 [0077] An example resin formulation according to the current invention is shown in TABLE 3. A matrix resin was prepared by mixing the epoxy ingredients at room temperature with polyether sulfone to form a resin mixture that was heated at 130 ° C for 60 minutes to completely dissolve the polyether sulfone. The mixture was cooled to 80 ° C and the rest of the ingredients (polyamide-imide particles, polyamide particles, polyure particlesPetition 870190116181, 11/11/2019, page 40/49
    28/31 tana and curing agent) were added and mixed intensively to form the uncured resin.
    TABLE 3
    Quantity (% weight) Ingredient 33.0 Trifunctional meta-glycidyl amine (MY0610) 15.0 Tetrafunctional para-glycidyl amine (MY721) 14.0 Low PM PES (VW-10700RP) 7.0 Polyurethane (SUNPU-170) 10.0 Polyamide-imide (Torlon 4000TF) 3.0 Polyamide particles (Orgasol 1002 D Nat 1) 18.1 3,3'-diaminodiphenyl sulfone (3,3'-DDS)
    [0078] The uncured resin had a viscosity that was suitable for use in the prepreg preparation. When it is impregnated in the fiber reinforcement, the resulting prepreg will have adhesion and useful life properties that are acceptable for use in forming molding articles. The sample prepregs can be prepared by impregnating one or more layers of unidirectional carbon fibers with the resin formulation of TABLE 3. Unidirectional carbon fibers are used for the preparation of a prepreg in which the resin in matrix represents about 35% by weight of the total weight of the uncured prepreg and the weight of the fiber area is about 190 g per square meter (gsm). A variety of prepreg applications can be prepared using standard prepreg manufacturing procedures. Prepregs are cured in an autoclave at 130 ° C for about 2 hours. The resulting composite parts have strength, damage tolerance properties and interlaminar fracture toughness that makes them suitable for use on main aircraft structures.
    [0079] A specimen for the solvent resistance test was prepared
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    29/31 using the resin formulation of TABLE 3. The resin was formed on a specimen that was 4.5 inches (11.4 cm) long, 0.5 inches (1.3 cm) wide and 0 , 63 inches (0.16 cm) thick. The resin was cured in an autoclave at 180 ° C for about 2h to form a cured test specimen. The test specimen was tensioned on a clothoid test tool to produce stresses ranging from 0% to a maximum of 2%. The strained test specimen was immersed in MEK at room temperature for a period of seven days. After seven days, the test specimen cracked, starting only in a place with a 1.08% tension on the test specimen.
    COMPARATIVE EXAMPLE 2 [0080] A comparative resin having the formulation shown in TABLE 4 was prepared in the same way as in example 2. The resin is equivalent to the resin in EXAMPLE 2, except that the low molecular weight PES has been replaced by high PES molecular weight.
    TABLE 4
    Quantity (% weight) Ingredient 33.0 Trifunctional meta-glycidyl amine (MY0610) 15.0 Tetrafunctional para-glycidyl amine (MY721) 14.0 High PM PES (Sumikaexcel 5003P) 7.0 Polyurethane (SUNPU-170) 10.0 Polyamide-imide (Torlon 4000TF) 3.0 Polyamide particles (Orgasol 1002 D Nat 1) 18.0 3,3'-diaminodiphenyl sulfone (3,3'-DDS)
    [0081] A specimen was prepared for the solvent resistance test using the resin formulation of TABLE 4. The resin was formed on a specimen that was 4.5 inches (11.4 cm) long, 0.5 inches (1.3 cm) wide and 0.63 inches (0.16 cm) thick. The resin was cured in an auto
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    30/31 clave at 180 ° C for about 2h to form a cured test specimen. The test specimen was tensioned in a standard clothoid test tool to produce stresses ranging from 0% to a maximum of 2%. The tensioned test specimen was immersed in MEK at room temperature and showed a fracture in less than ten minutes.
    EXAMPLE 3 [0082] TABLE 5 presents an example resin formulation according to the current invention. The uncured resin was prepared by mixing the epoxy ingredient at room temperature with polyether sulfone (PES) to form a resin mixture that was heated at 130 ° C for 60 minutes to completely dissolve the PES. The mixture was cooled to 80 ° C and BAPD was added as the curing agent, and mixed thoroughly to form the uncured resin.
    TABLE 5
    Quantity (% weight) Ingredient 24.3 Trifunctional para-glycidyl amine (MY0510) 24.3 Tetrafunctional para-glycidyl amine (MY721) 17.0 Low PM PES (VW-10700RP) 34.4 4,4'-bis (p-aminophenoxy) biphenyl (BAPB)
    [0083] The uncured resin had a viscosity that was suitable for use in the prepreg preparation. When impregnated in the fiber reinforcement, the resulting prepreg will have adhesion and useful life properties that are acceptable for use in forming molding articles. The example prepreg can be prepared using one or more layers of unidirectional carbon fibers with the resin formulation of TABLE 5. Unidirectional carbon fibers are used to produce a prepreg in which the matrix resin represents about 35% by weight of the total weight of the uncured prepreg and the weight of the fiber area is around 190 g per square meter (gsm).
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    31/31
    A variety of prepreg applications can be prepared using standard prepreg manufacturing procedures. Prepregs are cured in an autoclave at 180 ° C for about 2 hours. The resulting composite parts have strength, damage tolerance properties and interlaminar fracture toughness that makes them suitable for use on main aircraft structures.
    [0084] A specimen was prepared for the solvent resistance test using the resin formulation of TABLE 5. The resin was formed on a specimen that was 4.5 inches (11.4 cm) long, 0.5 inches ( 1.3 cm) wide and 0.63 inches (0.16 cm) thick. The resin was cured in an autoclave at 180 ° C for about 2h to form a cured test specimen. The test specimen was tensioned on a standard clothoid test tool to produce stresses ranging from 0% to a maximum of 2%. The strained test specimen was immersed in MEK at room temperature for a period of seven days. After seven days, the test specimen showed no crack or fracture. It is preferable that low molecular weight PES is used in combination with BAPD in view of the especially high solvent resistance that is obtained by this combination, as demonstrated by this example.
    [0085] Having described the example achievements of the current invention, it will be noticed by those trained in the art that the presentations are only examples, and that several other alternatives, adaptations and modifications in the scope of the current invention may be made. Accordingly, the current invention is not limited by the achievements described above, but is limited only by the following claims.
    权利要求:
    Claims (18)
    [1]
    1. Tenacified epoxy resin with uncured thermoplastic which, when cured, is resistant to solvent-induced cracking, said tenacified epoxy resin with uncured thermoplastic FEATURED by the fact that it comprises:
    an epoxy resin component comprising from 30 to 40% by weight of a trifunctional epoxy resin and from 10 to 20% by weight of a functional tetra epoxy resin, based on the total weight of said epoxy resin toughened with uncured thermoplastic;
    a thermoplastic component comprising from 10 to 20% by weight of a low molecular weight polyether sulfone, from 5 to 15% by weight of polyamideimide and from 1 to 5% by weight of polyamide particles, based on the total weight of said tenacified epoxy resin with uncured thermoplastic, wherein the molecular weight of said low molecular weight polyether sulfone is between 10,000 and 30,000 g / mol and where the amount of said low molecular weight polyether sulfone in said thermoplastic component is sufficient to produce said epoxy resin toughened with uncured thermoplastic, when cured, with said solvent-induced crack resistance; and a curative component comprising from 15 to 25% by weight of a curing agent, based on the total weight of said epoxy resin toughened with uncured thermoplastic.
    [2]
    2. Tenacified epoxy resin with uncured thermoplastic according to claim 1, CHARACTERIZED by the fact that it comprises an epoxy resin component comprising from 32 to 36% by weight of said trifunctional epoxy resin and from 14 to 26% by weight of said functional tetra epoxy resin, based on the total weight of said epoxy resin toughened with uncured thermoplastic;
    a thermoplastic component comprising from 13 to 16% by weight of
    Petition 870190116181, of 11/11/2019, p. 45/49
    2/4 a low molecular weight polyether sulfone, 9 to 11% by weight of polyamideimide and 2 to 4% by weight of polyamide particles, based on the total weight of said epoxy resin toughened with uncured thermoplastic, in that the amount of polyether sulfone in said thermoplastic component is sufficient to produce said epoxy resin toughened with uncured thermoplastic, when cured, with said solvent-induced crack resistance; and a curative component comprising from 18 to 20% by weight of a curing agent, based on the total weight of said epoxy resin toughened with uncured thermoplastic.
    [3]
    3. Tenacified epoxy resin with uncured thermoplastic according to claim 1, CHARACTERIZED by the fact that it comprises an elastic particle component comprising from 5 to 9% by weight of polyurethane particles, based on the total weight of said tenacified epoxy resin with uncured thermoplastic.
    [4]
    4. Tenacified epoxy resin with uncured thermoplastic according to claim 2, CHARACTERIZED by the fact that it comprises an elastic particle component comprising from 5 to 9% by weight of polyurethane particles, based on the total weight of said tenacified epoxy resin with uncured thermoplastic.
    [5]
    5. Tenacified epoxy resin with uncured thermoplastic according to claim 1, CHARACTERIZED by the fact that said trifunctional epoxy resin is a trifunctional meta-glycidyl amine.
    [6]
    6. Tenacified epoxy resin with uncured thermoplastic according to claim 2, CHARACTERIZED by the fact that said trifunctional epoxy resin is a trifunctional meta-glycidyl amine.
    [7]
    7. Epoxy resin toughened with uncured thermoplastic according to claim 5, CHARACTERIZED by the fact that the said tetrafun epoxy resin
    Petition 870190116181, of 11/11/2019, p. 46/49
    3/4 cional is a tetrafunctional para-glycidyl amine.
    [8]
    8. Tenacified epoxy resin with uncured thermoplastic according to claim 6, CHARACTERIZED by the fact that said tetrafunctional epoxy resin is a tetrafunctional para-glycidyl amine.
    [9]
    9. Epoxy resin tenacified with uncured thermoplastic according to claim 1, CHARACTERIZED by the fact that the molecular weight of said low molecular weight polyether sulfone is between 15,000 and 25,000 g / mol.
    [10]
    10. Epoxy resin toughened with uncured thermoplastic according to claim 2, CHARACTERIZED by the fact that the molecular weight of said low molecular weight polyether sulfone is between 15,000 and 25,000 g / mol.
    [11]
    11. Epoxy composite material toughened with uncured thermoplastic, CHARACTERIZED by the fact that it comprises a toughened epoxy resin with uncured thermoplastic, as defined in claim 1, and a fiber reinforcement.
    [12]
    12. Composite part, CHARACTERIZED by the fact that it comprises an epoxy composite material cured with an uncured thermoplastic as defined in claim 11, wherein said epoxy resin cured with an uncured thermoplastic has been cured.
    [13]
    13. Composite part according to claim 12, CHARACTERIZED by the fact that said composite part forms at least part of an aircraft's primary structure.
    [14]
    14. Method for the manufacture of a prepreg, CHARACTERIZED by the fact that it comprises the steps of:
    providing a tenacified epoxy resin with uncured thermoplastic as defined in claim 1; and combining said tenacified epoxy resin with uncured thermoplastic with a fiber reinforcement to produce said prepreg.
    Petition 870190116181, of 11/11/2019, p. 47/49
    4/4
    [15]
    15. Method for the manufacture of a prepreg according to claim 14, CHARACTERIZED by the fact that said epoxy resin toughened with uncured thermoplastic comprises an elastic particle component comprising from 5 to 9% by weight of polyurethane particles , based on the total weight of said epoxy resin toughened with uncured thermoplastic.
    [16]
    16. Method for the manufacture of a prepreg according to claim 14, CHARACTERIZED by the fact that said trifunctional epoxy resin is a trifunctional meta-glycidyl amine.
    [17]
    17. Method for the manufacture of a prepreg according to claim 16, CHARACTERIZED by the fact that said tetrafunctional epoxy resin is a tetrafunctional para-glycidyl amine.
    [18]
    18. Method for the manufacture of a prepreg according to claim 14, CHARACTERIZED by the fact that the molecular weight of said low molecular weight polyether sulfone is between 15,000 and 25,000 g / mol.
    类似技术:
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    BR112013005904B1|2020-02-04|tenacified epoxy resin with uncured thermoplastic, tenacified epoxy composite material with uncured thermoplastic, composite part and method for manufacturing a prepreg
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    US9187636B2|2015-11-17|Composite material with polyamide particle mixtures
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    同族专利:
    公开号 | 公开日
    CN103154131A|2013-06-12|
    US20120088864A1|2012-04-12|
    JP5681803B2|2015-03-11|
    JP2013538932A|2013-10-17|
    RU2581873C2|2016-04-20|
    AU2011313942B2|2013-12-05|
    WO2012051045A3|2012-10-11|
    WO2012051045A2|2012-04-19|
    CA2810589C|2017-01-03|
    CA2810589A1|2012-04-19|
    CN103154131B|2015-07-29|
    AU2011313942A1|2013-03-07|
    EP2627710A2|2013-08-21|
    US8686069B2|2014-04-01|
    RU2013120956A|2014-11-20|
    BR112013005904A2|2016-06-07|
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    法律状态:
    2018-04-03| B06F| Objections, documents and/or translations needed after an examination request according [chapter 6.6 patent gazette]|
    2019-08-13| B06U| Preliminary requirement: requests with searches performed by other patent offices: procedure suspended [chapter 6.21 patent gazette]|
    2020-01-14| B09A| Decision: intention to grant [chapter 9.1 patent gazette]|
    2020-02-04| B16A| Patent or certificate of addition of invention granted [chapter 16.1 patent gazette]|Free format text: PRAZO DE VALIDADE: 20 (VINTE) ANOS CONTADOS A PARTIR DE 06/10/2011, OBSERVADAS AS CONDICOES LEGAIS. |
    优先权:
    申请号 | 申请日 | 专利标题
    US12/902,312|US8686069B2|2010-10-12|2010-10-12|Solvent resistance of epoxy resins toughened with polyethersulfone|
    PCT/US2011/055096|WO2012051045A2|2010-10-12|2011-10-06|Improving solvent resistance of epoxy resins toughened with polyethersulfone|
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