RU2718831C1 - Epoxy binder, prepreg based thereon and article made therefrom - Google Patents

Abstract

FIELD: chemistry; technological processes.

SUBSTANCE: invention relates to making melt epoxy binders for producing structural polymer composite materials (PCM) resistant to impact effects based on fibrous reinforcing fillers formed by prepreg technology, which can be used in automotive and shipbuilding, for making functional prosthetic products, in sports and leisure industry and in other industries. Epoxy binder includes a mixture of liquid and solid difunctional epoxy resins based on bisphenol A, a rubber-containing component consisting of core-shell type rubber nanoparticles distributed in epoxy resin based on bisphenol A, a thermoplastic, a latent hardener – dicyandiamide, a curing accelerator – asymmetrically disubstituted urea, a difunctional epoxy resin based on bisphenol F and a polyfunctional epoxy resin. Prepreg contains said epoxy binder and fibrous filler. Product is produced by vacuum-pressure molding or direct pressing of prepreg.

EFFECT: invention is characterized by high technological viability of binder and prepregs based on it at temperature of 25 °C, increased glass transition temperature, as well as an index of impact strength of the formed PCM samples.

8 cl, 3 tbl, 10 ex

Description

The invention relates to the field of creating melt epoxy binders to obtain impact-resistant structural polymer composite materials (PCM) based on fiber reinforcing fillers formed by prepreg technology, which can be used in auto and shipbuilding, for the manufacture of functional prosthetics, in industry sports and recreation and other industries.

The prior art epoxyphenol binder for the manufacture of fiberglass intended for the manufacture of products in the prosthetic industry using prepreg technology (see RU 2118966 C1, publ. 09/20/1998). The binder consists of: epoxidian oligomer, grade ED-20, rezol phenol-formaldehyde resin, grade SF 341, alcohol-acetone mixture and a complex of boron trifluoride with isophorondiamine. The prepreg obtained by mortar technology consists of: 61.6 - 61.9 wt. % epoxyphenolic binder and 38.1 - 38.4 wt.% fiberglass brand T-13.

The main disadvantage of this epoxyphenolic binder is that it is a composition of the mortar type and contains a large number of volatile organic solvents (up to 50%), which complicates the formation of PCM on its basis and poses a risk of air pollution of industrial premises, contributing to the deterioration of sanitary and hygienic , fire and environmental safety of the process of its processing. In addition, the removal of volatile solvents from the composition of the prepreg binder during molding of products usually leads to the creation of materials with high porosity, the formation of defects and shells, which are stress concentrators and weaken the polymer base. Defects that have arisen over time grow and become the main causes of the destruction of polymer composite products under critical shock loads.

Another epoxy binder is known (see US6838176 B2, working example 27, publ. 04.01.2005), containing: 38.0 mass. % epoxy resin based on N, N'-tetraglycidyl-4,4'-diaminodiphenylmethane brand Epikote 604, 25.3 wt.% epoxy resin aminophenol type brand Sumiepoxy ELM-100, 6.3 wt.% latent catalyst based on imidazole brand Novacure HX3722, 28.5 mass. % hardener 4,4'-diaminodiphenylsulfone brand Seikacure and 1.9% of the mass. Omicure 94 phenyldimethylurea.

A prepreg is prepared by impregnating a TR50S-12L reinforcing fiber material with this epoxy binder. The created prepreg can be used for the manufacture of sports and entertainment products, transport elements and other industrial applications.

One of the main disadvantages of this invention is that there are no modifiers in the binder to increase the deformation resistance, impact strength and crack resistance, which does not guarantee long-term and reliable operation of the PCM products based on the proposed binder and prepreg under conditions of mechanical stress. Since it is known that with all its advantages, most cured unmodified epoxy compositions are quite brittle materials with low deformation and impact resistance.

The closest analogues adopted for the prototype are (see US6063839 A1, working example 3, publ. 16.05.2000):

- epoxy composition, which is a mixture of a liquid difunctional epoxy resin based on bisphenol A brand Epikote 828 - 32.3 mass. %, solid difunctional epoxy resin based on bisphenol A brand Epikote 1001 - 48.4 mass. %, rubber, which is a core-shell nanoparticle of the brand Kureha Paraloid EXL-2655, consisting of a core of a copolymer of butadiene and styrene, and a shell of an alkyl methacrylate polymer - 8.1 mass. %, thermoplastic polyethersulfone brand PES 5003P - 4.8 wt. %, latent hardener of dicyandiamide brand DICY7 - 3.2 wt. % and accelerator curing asymmetric disubstituted urea brand DCMU-99 - 3.2 mass. %;

- unidirectional prepreg containing the specified epoxy binder and carbon reinforcing fiber brand Toray T700S (manufacturer Toray Co.), with a ratio of components: binder - 33 mass. %, carbon fiber filler - 67 mass. %;

- the prepreg product is obtained by vacuum-autoclave molding under vacuum of 0.29 MPa according to the following conditions: temperature increase at a speed of 1.5 ° C / min to 135 ° C; holding at a temperature of 135 ° C for 2 hours. Golf clubs, baseball bats, tennis and badminton rackets, hockey sticks, etc. are made from the obtained prepreg.

The disadvantages of these prototypes are:

- reduced technological viability of the epoxy binder and prepregs based on it at a temperature of 25 ° C (a quick set of viscosity of the binder during storage);

- low thermomechanical (glass transition temperature) properties and insufficiently high resistance to shock loads (low impact strength) of the formed PCM samples.

The presence in the binder-prototype of a large number (3.2 wt.%) Of the curing accelerator of asymmetric disubstituted urea DCMU-99 with high catalytic activity, accelerates the curing process of the binder even at room temperature and leads to a rapid increase in viscosity, reducing its viability and a prepreg based on it during storage at a temperature of 25 ° C, which significantly impairs their technological properties. The decrease in technological characteristics of prepregs, which is actively progressing during storage, decreases the viscosity of the binder and changes associated with this process: decrease in drapeability, decrease in elasticity and flexibility, the disappearance of the necessary contact tack, etc.) complicates the assembly of the prepreg technological package, which is especially problematic in the manufacture of parts of complex configuration .

In addition, before the synthesis of the prototype binder, rubber nanoparticles are combined with a liquid epoxy resin to form a dispersion. The rubber-containing systems obtained in this way are not stable and not uniform in composition, are characterized by rapid deposition of nanoparticles, their agglomeration, the ability to be filtered when passing through a fibrous filler, which makes it impossible to create homogeneous epoxy binders of a homogeneous composition.

The technical problem to which the invention is directed is to create high-quality products from polymer composite materials with high thermomechanical properties and with increased resistance to shock loads.

The technical result achieved by solving the technical problem is to increase the technological viability of the binder and prepregs based on it at a temperature of 25 ° C by reducing the growth coefficient of the binder viscosity, increasing the glass transition temperature, as well as the impact strength of the formed PCM samples.

The technical result is achieved by the fact that the epoxy binder comprises a mixture of liquid and solid difunctional epoxy resins based on bisphenol A, rubber, thermoplastic, latent hardener - dicyandiamide (DCDA), a curing accelerator - asymmetrically disubstituted urea, while rubber containing rubber is used a component consisting of rubber nanoparticles of the "core-shell" type distributed in an epoxy resin based on bisphenol A, as a thermoplastic, a thermoplastic selected from the group: polyari is used lsulfon, polyethersulfone, phenoxy resins or mixtures thereof, and also contains a difunctional epoxy resin based on bisphenol F and a polyfunctional epoxy resin, in the following ratio of components, mass. % .:

liquid difunctional epoxy based on bisphenol A 9.0 - 13.5 solid difunctional epoxy based on bisphenol A 8.0 - 14.0 latent hardener - dicyandiamide 5.0 - 7.0 curing accelerator - asymmetrically disubstituted urea 0.5 - 2.5 rubber component 36.0 - 44.0 thermoplastic 7.0 - 13.0 difunctional epoxy based on bisphenol F 9.5 - 13.5 polyfunctional epoxy 6.5 - 10.0

In addition, the epoxy binder may contain a technological additive based on a mixture of oligomeric substances and agents wetting the reinforcing fibers of the used fillers in an amount of 0.1 - 1.0 mass. % of the total composition.

To achieve a technical result, a prepreg is also proposed, including the specified epoxy binder and a fibrous filler, in the following ratio of components, mass. %:

epoxy binder 30.0 - 50.0 fiberfill 50.0 - 70.0.

As the fibrous filler can be used fibrous glass, carbon and organofillers or combinations thereof (hybrid laminated plastics).

Products are obtained by vacuum autoclave molding or direct compression of a prepreg based on the claimed epoxy binder.

The proposed epoxy binder is characterized by an optimally balanced ratio of the components used, which provides increased technological viability of the prepregs based on it and contributes to the formation of PCM with increased thermomechanical characteristics and increased stable impact indicators in comparison with the prototype.

To create an epoxy binder, low viscosity epoxy resins Araldite GY 250 (manufactured by Huntsman Advanced Materials), D.E.R. can be used as a liquid difunctional epoxy based on bisphenol A (4,4'-dihydroxy-2,2-diphenylpropane). 330 (manufacturer Olin) and others;

As a solid difunctional epoxy resin based on bisphenol A (4,4'-dihydroxy-2,2-diphenylpropane), crystalline epoxies of the grades YD-011 (manufactured by KUKDO Chemical Co., Ltd), NPES-901 (manufactured by Nan) can be used Ya Plastics Corporation) et al.

As the latent hardener of DCDA in the invention, the following can be used: DYHARD 100S (manufacturer AlzChem), DICY 7 (manufacturer Japan Epoxy Resins), etc .;

As an accelerator of asymmetrically disubstituted urea, for example, 2,4-toluylidene bisdimethyl urea (brand Omncure U-24, manufacturer CVC Thermoset Specialties), 1,1-dimethyl-3- (3,4-dichlorophenyl) urea (brand DCMU-99, manufacturer of Hodogaya Chemical Industry Co), 1,3-bis- (N, N-dimethylcarbamide) -4-methylbenzene (brand DYHARD UR-500, manufacturer AlzChem), urea brand Dyhard URAcc 13 (manufacturer AlzChem), etc. .;

As a rubber-containing component, one of the compositions with the brand name Kane Ace MX120 or Kane Ace MX125 (manufactured by Kaneka Corporation), consisting of rubber nanoparticles of the "core-shell" type distributed in an epoxy resin based on bisphenol A and others, can be used. .;

As a thermoplastic, one thermoplastic can be used selected from the series: PSFF-30 polyarylsulfone (manufactured by JSC Institute of Plastics named after G. Petrov) or another, or polyethersulfone, such brands as PSK-1 (manufactured by Institute Institute G.S. Petrov plastics "), PES5003P (manufacturer Sumitomo Chemical KK) or another, or phenoxysmol grades, PKHB or PKHH (manufacturer Gabriel Phenoxies Inc), etc., or mixtures thereof;

As a difunctional epoxy resin based on bisphenol F (diphenylolmethane), epoxy resins of the Araldite GY 285 grade (manufactured by Huntsman Advanced Materials), resin YDF-170 can be used (manufacturer KUKDO Chemical Co., Ltd) and others;

As a polyfunctional epoxy resin, one of the resins selected from the group can be used: a polyfunctional epoxy resin based on phenol of the EN-6 brand (manufactured by Doros LLC), a polyfunctional nitrogen-containing epoxy resin with chlorine grade ECD (manufactured by Khimex Limited CJSC), ETF polyfunctional epoxy resin based on triphenol (manufacturer LLC NPP Macromer) and others;

As a technological additive based on a mixture of oligomeric substances and agents wetting the reinforcing fibers of the used fillers, a product with the trademark BYK-P 9920 (manufactured by BYK Additives & Instruments) or others can be used.

The proposed binder contains not only a smaller amount of curing accelerator - asymmetric disubstituted urea (0.5 ÷ 2.5 wt.%), But also a multifunctional epoxy resin with reduced reactivity. The steric factors inherent in large compact molecules of polyfunctional epoxy resins have a restraining effect on their reactivity: bulk structures formed during the polymerization actively block reaction centers, which complicates and reduces their reactivity. Due to the observed synergistic effect when using a small optimal amount of curing accelerator - asymmetric disubstituted urea and low-active polyfunctional epoxy, the curing process decreases at room temperature and the proposed epoxy binder is characterized by a low viscosity growth rate, and the prepregs based on it have improved technological characteristics - long-term viability at a storage temperature of 25 ° C.

The widely used latent hardener - dicyadiamide (DCDA), is a multifunctional conjugated class system of the guanidines class, capable of deep degrees of cure of epoxides by polycondensation and polymerization mechanisms at the same time, allows to obtain a densely crosslinked or less densely crosslinked molecular structure of the cured epoxide binder depending on its amount used. The composition of the proposed epoxy binder contains a larger amount of latent hardener DTSDA (5.0 ÷ 7.0 wt.%) Than in the considered binder prototype (3.2 wt.%), Which allows to obtain a more densely crosslinked molecular structure of the cured epoxypolymer. Such a frequently crosslinked (with a high density of chemical bonds) formed cured polymer structure is characterized by increased thermomechanical characteristics and provides higher heat resistance (glass transition temperature) of the claimed epoxy binder and composite materials based on it, in comparison with the prototypes under consideration.

It is known that to improve the impact characteristics of the epoxy binder and materials based on it, physicochemical modification of the polymer composition is usually carried out by introducing effective modifiers to increase the strength characteristics and impact resistance — rubbers or thermoplastics — into it.

The used thermoplastics-modifiers during curing usually do not integrate into the epoxy composite structure, but form a separate microphase, which provides a reduction in internal stresses and an increase in deformation resistance, impact strength, elasticity and crack resistance. Under the influence of critical shock loads on modified materials, growing microcracks, bumping into the plastic phase in the polymer matrix, dissipate, and their growth is inhibited. To further increase microcracks, much more energy is required, which ultimately increases the required energy costs for the complete destruction of the material, increasing its impact strength.

In the claimed epoxy binder, along with a thermoplastic, a rubber-containing component is used as an impact modifier, which is an epoxy resin based on bisphenol A, in which 25 masses are evenly distributed. % rubber nanoparticles of the type "core-shell". Rubber nanoparticles of the "core-shell" type consist of an outer shell and core and are designed in such a way that the outer shell is a solid material based on acrylate and liquid polybutadiene-styrene rubber is used as the core. An advantage of using such reinforcing nanoparticles is their ability to evenly distribute throughout the composition, forming phase microdomains in the form of a rubbery material. Under critical loading of such structures, the deformation energy does not just dissipate at the end of the crack, as is the case with thermoplastics, but leads to cavitation of the core of rubber nanoparticles, which contributes to a significant absorption of the destruction energy upon impact, and interrupts further destructive action, demonstrating the effectiveness of the modifier used to increase impact strength . The increased content of hardening modifiers - rubbers and thermoplastics in the binder contributes to a significant increase in the impact strength of the formed epoxy composites.

The composition of the proposed epoxy binder contains a large number of impact modifiers (rubber-containing component 36 ÷ 44 wt.%, Of which 9 ÷ 11 wt.% (25 wt.%) Are rubber nanoparticles; thermoplastic 7 ÷ 13 wt.%), than in the considered prototype binder (rubber nanoparticles 8.1 wt.%; thermoplastic 4.8 wt.%), which allows to obtain PCM samples based on it with an increased value of impact strength.

However, the combined use of a large number of rubber-containing and thermoplastic modifiers can lead to a significant increase in viscosity and a decrease in the stickiness of the binder, which will complicate and increase the laboriousness of the process of producing prepreg and PCM products based on it. The use of a low-viscosity difunctional epoxy resin based on bisphenol F, acting as an active diluent, allows you to adjust the rheological characteristics of the proposed binder and makes it possible to optimize the technological characteristics of the binder (viscosity and stickiness) for the prepreg technology.

The use in the proposed binder of industrially produced, extremely stable rubber-containing components based on epoxy resin in which rubber core-shell type nanoparticles are uniformly distributed with a constant concentration in the volume, contributes to the production of a uniform epoxy binder and a uniform polymer structure of PCM on its basis, which is characterized by maximum impact toughness of PCM samples with a minimum coefficient of variation.

The introduction of a small amount of a technological additive in the claimed epoxy binder improves the wetting and impregnation of the fibrous filler in the manufacture of prepregs, which affects the decrease in the amount of air involved and porosity during the molding of PCM products, and also allows to get rid of unimpaired places and reduce the amount of marriage.

Examples of implementation

Preparation of the claimed epoxy binder

Example 1 (table. 1)

In a clean and dry reactor, 9% by weight of liquid D.E.R. bisphenol A epoxy resin was used. 330, 14 wt.% Solid bisphenol A based epoxy resin of grade YD-011, 9 wt.% Difunctional epoxy based on bisphenol A grade YDF-170, 10 wt.% Polyfunctional epoxy based on triphenol grade ETF and operating the stirrer was heated to a temperature of 100 ° C. The mixture was stirred at a speed of 250 rpm at a temperature of 100 ° C until the resins were completely combined. Then the temperature was raised to 150 ° C and the speed of rotation of the mixer was increased to 300 rpm.

In small portions when the stirrer is operating at temperature
150 ° C was introduced 13.0 mass. % thermoplastic brand PES5003P and mixed until a homogeneous mass.

Then, with the stirrer working, 36 masses were charged in small portions. % rubber-containing component of the brand Kane Ace MX120 and was stirred at a speed of 350 rpm at a temperature of 130 ° C until a homogeneous mass.

The temperature of the reaction mixture was reduced to 110 ° C, loaded in small portions with a working stirrer 7.0 mass. % dicyandiamide brand DYHARD 100S, while increasing the speed of the mixer to 400 rpm Stirred until smooth.

Reduced temperature to 80 ° C and added in small portions
0.5 mass. % curing accelerator asymmetrically disubstituted urea brand Omncure U-24 and 1.0 mass. % technological additive brand BYK-P 9920 with stirring at a speed of 250 rpm for 60 minutes to obtain a completely homogeneous mass. The mixer was turned off and the finished binder was poured through the drain fitting.

The manufacturing technology of epoxy binders according to examples 2 to 10 (table. 1) was used analogously to example 1.

Obtaining the declared prepreg

Example 1 (table. 2)

Obtaining a prepreg was carried out by applying 30 mass. % epoxy binder, prepared according to the recipe of example 1 (table. 1) by means of an impregnation machine at a temperature of 80 ° C on a carbon tow T700S-12K-50C in the amount of 70 mass. %

Prepregs for examples 3, 7, 9 were made using a T700S-12K-50C carbon bundle, for examples 2, 4, 6, 10 using a glass roving T30 SE 1200 17-600 CF, for examples 5 and 8 using aramid fabric CBM art . 56313

Manufacture of the claimed product

Example 1 (table. 3)

A prepreg based on a binder and a carbon tow T700S-12K-50C, obtained according to the recipe of Example 1 (Table 2) was cut according to the templates, cut blanks were laid out on a mold, and a technological package was assembled. The manufacture of the product was carried out by vacuum-autoclave molding of the obtained technological package at an excess pressure of 0.6 - 0.7 MPa, according to the temperature regime: raising the temperature at a speed of 1.5 ° C / min to 135 ° C, holding for 1 hour at a temperature (135 ± 5) ° C. Then the molded article was removed from the autoclave. Thus, a detail was obtained from the design of the prosthesis for running - a dynamic foot.

Example 2 (table. 3).

From a cut-out prepreg based on a binder and glass roving grade T30 SE 1200 17-600 CF, obtained according to the recipe of example 2 (table 2), a technological package was formed, which was placed in the mold, where the product was molded by direct compression by heating the molds on the press for heat setting at a temperature of (135 ± 5) ° С for 30 ± 10 minutes and a pressure of 8 - 10 atm. Then the molded product was removed from the mold and subjected to external decoration. Thus, a hockey stick was obtained.

Example 3 (table. 3).

A hybrid technological process was formed from the cut preforms of prepregs based on a binder, carbon tow T700S-12K-50C obtained according to the recipe of Example 3 (Table 2) and glass roving grade T30 SE 1200 17-600 CF obtained according to the recipe of Example 4 (Table 2). package by layer-by-layer laying of blanks based on glass and carbon filler, which was placed in the mold, where the product was molded by direct pressing by heating the molds on a heat-setting press at a temperature of (135 ± 5) ° С for 30 ± 10 minutes and pressure 8 - 10 atm. Then the molded product was removed from the mold. Thus received a cross-country skiing hull.

Based on the prepared prepregs according to examples 5-10 (table. 2), the following products were made:

- according to a technology similar to example 1 (vacuum-autoclave molding method): according to example 5 - a protective helmet, according to example 7 - a receiving sleeve of a prosthesis, according to example 8 - a shell of a ski boot;

- according to a technology similar to example 2 (direct pressing method): according to example 6 - a surfboard, according to example 9 - a ski boot cuff, according to example 10 - a bicycle saddle.

The compositions of the binders according to the invention and the prototype are shown in table 1, the compositions of the prepregs according to the invention and the prototype in table 2, the properties of the binders according to the claimed invention and the prototype, prepregs and PCM made on their basis in table 3. The invention is not limited to the examples.

Comparative data from table 3 show that the proposed epoxy binder provides advantages compared with the prototype:

- is more technologically advanced, because it is characterized by more stable rheological characteristics, since as a result of its storage for 28 days at a temperature of 25 ° C, there is no significant increase in viscosity compared to the initial value (coefficient of increase in viscosity of the binder is 1.0 ÷ 1.2 ), the prototype also has an increase in viscosity up to 50% (the coefficient of viscosity increase of the binder of the prototype is 1.5). Such high chemical stability of the claimed epoxy binder at room temperature, the absence of a rapid increase in viscosity, contributes to the long-term preservation of the necessary technological characteristics of the prepreg based on it (good drape, high elasticity and flexibility, optimal contact tack, etc.), which simplifies the technological process of its processing into PCM, and also makes it possible to manufacture prepregs based on it with long viability - at least 45 days at room temperature, in Ichiye from prototype whose viability at room temperature is only 28 days. Such technological characteristics of the claimed epoxy binder make it possible to create technologically advanced and long-lived prepregs based on it, which can provide a reduction in energy consumption during transportation and storage until processing by eliminating the use of refrigeration equipment, which in turn has a positive effect on economic production indicators;

- forms PCM products at a curing temperature of 135 ° C characterized by higher thermomechanical characteristics - glass transition temperature Tg = 141 ÷ 148 ° C, in contrast to the prototype with a glass transition temperature Tg = 125 ° C. The proposed binder provides the glass transition temperature of the molded product above the curing temperature by 6 ÷ 13 ° C, which makes it possible to extract the final product from the press without the need for cooling to low temperatures. When the molded product is removed from the mold at a higher temperature compared to its glass transition temperature, as would be the case if the product was molded from the selected prepreg prototype, the finished product is usually skewed and deformed. Such characteristics of the proposed epoxy binder and prepreg based on it not only provide high-quality products from composite material, preventing their deformation and eliminating the stage of cooling the molded part before it is removed from the press, but also provide increased production efficiency, reduce the production cycle and reduce the complexity of manufacturing PCM products, saving money and increasing productivity, without increasing the number of products used ss-forms and production areas;

- contributes to the creation of PCM products with increased resistance to impact loads, since they are characterized by higher values of Charpy impact strength α = 162 ÷ 172 kJ / m ² , which is one of the criteria for assessing the resistance to impact destruction of a material. The value of Charpy impact strength of the proposed polymer composite material is more than 10 ÷ 17% higher than that of the prototype. The results obtained confirm that the proposed epoxy binder and prepregs based on it are capable of forming sufficiently impact resistant materials;

- provides uniformity of the created polymer structure of PCM on its basis, which contributes to a small variation in impact resistance and leads to a decrease in the coefficient of variation of Charpy impact strength by about 2 times compared with the value of PCM based on the prepreg prototype (K is the _{coefficient of variation of} impact resistance characteristics of samples PCM based on materials of the prototype = 9.9; K _{coefficient of variation of} impact resistance characteristics of PCM samples based on the developed binder = 4.6 ÷ 5.0).

Thus, the claimed epoxy binder and prepreg made on its basis are characterized by improved properties, which simplifies the process of obtaining PCM and provides cost savings for their manufacture, transportation, and also makes it possible to obtain products with higher and more stable fracture toughness and resistance to shock effects, which ensures their long-term and reliable operation in conditions of increased mechanical loads.

Table 2. The composition of the prepreg prototype and the claimed invention

Name of components Prototype
US6063839 The composition according to examples, wt.% 1 2 3 4 5 6 7 8 nine 10 Binder 33 thirty 33 45 40 47 38 43 37 34 fifty Carbon Harness Torayca T700S 67 - - - - - - - - - - Carbon Harness T700S-12K-50C - 70 - 55 - - - 57 - 66 - Glass Roving T30 SE 1200 17-600 C-F - - 67 - 60 - 62 - - - fifty CBM aramid fabric art. 56313 - - - - - 53 63

Table 3. Properties of the binder of the claimed invention and prototype, prepregs and RMBs made on their basis

Name No. of examples Prototype
US6063839 1 2 3 4 5 6 7 8 nine 10 The coefficient of viscosity increase of the binder during storage at a temperature of 25 ° C for 25 days 1,0 1,1 1,0 1,1 1,0 1,0 1,0 1,1 1,2 1,2 1,5 The viability of the binder in the prepreg during storage at a temperature of 25 ° C for at least 24 hours (technological viability of the prepreg) fifty 51 51 54 fifty 49 47 45 46 45 28 Glass transition temperature of PCM samples (DSC method), Tg, ° С 140 141 142 143 142 142 143 145 146 148 125 Charpy impact strength of PCM samples at temperature
20 ° C, kJ / m ² 172 - 162 - - - 165 - 167 - 147 To the _{coefficient of variation of} impact strength characteristics of PCM samples (Charpy impact strength at a temperature of 20 ° C),% 4.9 - 4.8 - - - 5,0 4.6 - 9.9

Claims (10)

1. Epoxy binder for structural polymer composite materials, including a mixture of liquid and solid difunctional epoxy resins based on bisphenol A, rubber, thermoplastic, latent hardener - dicyandiamide, curing accelerator - asymmetrically disubstituted urea, characterized in that it contains rubber as rubber a component representing an epoxy resin based on bisphenol A, in which 25 wt.% are evenly distributed % rubber core-shell type nanoparticles, the outer shell of which is a solid material based on acrylate, and inside, as the core, liquid polybutadiene-styrene rubber is used, a thermoplastic selected from the group consisting of polyarylsulfone, polyethersulfone, phenoxy resin or a mixture thereof and also contains a bisphenol F-based differential epoxy resin and a polyfunctional epoxy resin selected from the group consisting of a nitrogen-containing epoxy resin, phenol-based resin, or a mixture thereof, as follows m ratio, wt. %: liquid difunctional epoxy based on bisphenol A 9.0-13.5 solid difunctional epoxy based on bisphenol A 8.0-14.0 latent hardener - dicyandiamide 5.0-7.0 curing accelerator - asymmetrically disubstituted urea 0.5-2.5 rubber component 36.0-44.0 thermoplastic 7.0-13.0 difunctional epoxy based on bisphenol F 9.5-13.5 polyfunctional epoxy 6.5-10.0 2. The epoxy binder according to claim 1, characterized in that it further comprises a technological additive based on a mixture of oligomeric substances and agents wetting the reinforcing fibers of the composition. 3. A prepreg comprising an epoxy binder and a fibrous filler, characterized in that the binder according to any one of paragraphs is used as the epoxy binder. 12. 4. The prepreg according to claim 3, characterized in that it contains components in the following ratio, wt. %: epoxy binder 30.0-50.0 fiberfill 50.0-70.0 5. Prepreg according to any one of paragraphs. 3, 4, characterized in that as a fibrous filler contains fibrous carbon filler. 6. Prepreg according to any one of paragraphs. 3, 4, characterized in that as a fibrous filler contains fibrous glass filler. 7. Prepreg according to any one of paragraphs. 3, 4, characterized in that as the fibrous filler contains a fibrous organofiller. 8. The product, characterized in that it is made by the method of vacuum autoclave molding or direct compression of the prepreg according to any one of paragraphs. 3-7.