RU2740286C1 - Solution-free method of producing phthalonitrile prepreg and polymer composite material based thereon - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to polymer chemistry and the technology of producing polymer composite materials (PCM), specifically to a method of producing a prepreg with a phthalonitrile matrix in a nonsoluble technology, as well as to a method of producing polymer composite material for use in aircraft and space industries. Method of producing a prepreg with a phthalonitrile matrix involves forming, first, a film of a low-melting phthalonitrile binder with thickness of 20–400 mcm between two polymer films with an anti-adhesion coating. Formation of film is carried out in thermo press at pressure from 2 to 10 bar and temperature from 80 °C to 140 °C for 20–600 seconds. Then film of low-melting phthalonitrile binder is applied by direct method using roller on reinforcing filler at 35 ± 5 wt. % binder per weight of reinforcing filler. Method of producing polymer composite material consists in assembling vacuum package around layer-by-layer layers of said prepreg with phthalonitrile matrix, evacuating air to vacuum values <1 mm Hg and cured. Curing is carried out according to the following mode: heating to 120–150 °C at speed 2 ± 0.5 °C/min and contact pressure, followed by heating to 180 ± 2 °C at speed 2 ± 0.5 °C/min and pressure 2–8 bar, subsequent pressure increase up to 10 ± 0.5 bar, holding at this temperature for 8 ± 0.1 hour. Further, composite is removed from mold, post-hardened at temperature of 330 ± 5 °C for 8 ± 0.1 h and cooled to room temperature with cooling rate of not more than 5 °C/min.

EFFECT: invention enables to obtain prepregs with phthalonitrile matrices without using organic solvents and obtain a polymer composite material with high strength properties and high heat resistance.

8 cl, 5 tbl, 35 ex, 5 dwg

Description

Technology area

The invention relates to the field of polymer chemistry and technology for producing polymer composite materials (PCM), namely to a method for producing phthalonitrile prepregs using solutionless technology, to obtain PCM with high temperature resistance for use in the aviation and space industries.

State of the art

Phthalonitrile binders are promising materials for PCM matrices due to their outstanding thermal and oxidative stability, glass transition temperature, high moisture and fire resistance, as well as good mechanical characteristics [T.M. Keller, Phthalonitrile-based high temperature resin, J. Polym. Sci. Part A Polym. Chem. 26 (1988) 3199-3212. doi: 10.1002 / pola.1988.080261207; S.B. Sastri, T.M. Keller, Phthalonitrile polymers: Cure behavior and properties, J. Polym. Sci. Part A Polym. Chem. 37 (1999) 2105-2111. doi: 10.1002 / (SICI) 1099-0518 (19990701) 37:13 <2105 :: AID-POLA25> 3.0.CO; 2-A; M.L. Warzel, T.M. Keller, Tensile and fracture properties of a phthalonitrile polymer, Polymer (Guildf). 34 (1993) 663-666. doi: 10.1016 / 0032-3861 (93) 90570-Z].

For the manufacture of PCMs with phthalonitrile binders, the most widely described methods of molding from a fabric pre-impregnated with a binder - prepreg. The prepreg itself is usually obtained by impregnation with a reinforcing filler solution. The first works on this topic were done by the scientific group of Teddy Keller [S.B. Sastri, J.P. Armistead, T.M. Keller, Phthalonitrile-carbon fiber composites, Polym. Compos. 17 (1996). doi: 10.1002 / pc.l0674].

4,4'-bis (3,4-dicyanophenoxy) biphenyl (I) was used as a monomer in this work, and 1,3-bis (3-amino-phenoxy) benzene (II) was chosen as a polymerization initiator. To obtain the prepreg, not the monomers themselves were used, but the prepolymer obtained from the monomer and the hardener, with a mass fraction of the latter of 1.5-2.3%. The prepolymer can subsequently be cured at elevated temperatures (375 ° C) to obtain a fully crosslinked structure with good thermal and oxidative stability. The use of a prepolymer is also due to excessively high softening points of individual monomers, which, as a consequence, will lead to the binder shedding from the reinforcing filler.

The prepolymer was prepared as follows: 4,4'-bis (3,4 ditsianofenoksi) biphenyl was melted in a vessel _(Tm = 234 ° C). 1,3 bis (3-amino-phenoxy) benzene was added portionwise to the melt and stirring was started. The reaction was carried out at 250 ° C for 15 minutes. Thereafter, the reaction mixture was cooled to room temperature. According to the source, the resulting product is soluble in many organic solvents, has a glass transition temperature of ~ 80 ° C and can be stored at room temperature for an unlimited amount of time.

The prepreg itself was obtained using carbon tapes made of IM-7 12K fiber (Hexcel), impregnating them with a prepolymer solution in a mixture of dimethylacetamide and n-methylpyrrolidone in a ratio of 9: 1. The PCM sample was molded in a metal mold under a pressure of 1.3 MPa and temperatures up to 375 ° C. An obvious problem with this method is the need to select a solvent suitable for a specific composition and its further removal from the prepreg. Insufficient drying can ultimately lead to the formation of undesirable porosity and consequently reduced mechanical properties. In addition, the complexities of forming such a composite include high viscosity values at processing temperatures (> 25 kPa⋅s) and a relatively slow start of the onset of polymerization (> 45 minutes). The use of higher contents of the hardener (> 2.3%) led to a faster start of polymerization, but also increased the viscosity of the binder, which led to the formation of voids in the bulk of the composite, which affected the mechanical characteristics. The strength properties in the direction of the fiber were relatively high (Table 1).

The use of fiberglass in the work of the same authors did not lead to qualitatively better results (Table 1) [S.B. Sastri, J.P. Armistead, T.M. Keller, U. Sorathia, Phthalonitrile-glass fabric composites, Polym. Compos. 18 (1997) 48-54. doi: 10.1002 / pc. 10260]. Replacing the hardener m-APB (III) with p-BAFS (IV) gives lower mechanical characteristics of the resulting PCM (Table 1) [D.D. Dominguez, H.N. Jones, T.M. Keller, The effect of curing additive on the mechanical properties of phthalonitrile-carbon fiber composites, Polym. Compos. 25 (2004) 554-561. doi: 10.1002 / pc.20049]. The preparation of the prepreg with p-BAFS was carried out according to a similar scheme; the content of the hardener in the prepolymer was 2.4 wt. %.

Note: 1 - interlayer shear strength, 2 - tensile strength, 3 - bending strength

From the prior art, a method for producing PCM with a phthalonitrile matrix based on a substituted phenol-formaldehyde resin is known (Scheme 1) [D. Augustine, D. Mathew, C.P.R. Nair, Phenol-containing phthalonitrile polymers - synthesis, cure characteristics and laminate properties, Polym. Int. 62 (2012) n / a-n / a. doi: 10.1002 / pi.4393]. Varying the degree of substitution of hydroxyl groups for phthalonitrile from 44 to 99%, a number of binders were obtained, cured according to the scheme 100 ° C - 30 min => 150 ° C - 30 min => 200 ° C - 30 min => 250 ° C - 1 hour => 300 ° С - 1 hour => 350 ° С - 3 hours. The substituted novolac-phthalonitrile resins used had codes NLPN-1, NLPN-2, NLPN-3, NLPN-4 and had a hydroxyl substitution degree of 44%, 71%, 87% and 99%, respectively.

The prepreg was obtained by impregnating a fabric based on T-300 fiber (Toray) with a binder solution in methyl ethyl ketone per 70 wt. % reinforcing filler in the final composite. Drying of sheets was carried out in vacuum at a temperature of 60 ° C. PCM was obtained by laying the prepreg in a metal tooling and heating according to the scheme used to cure the binder. SEM micrographs were also obtained for the tested samples (Fig. 1).

From the prior art, methods are known for producing materials based on the "third" generation of phthalonitriles (X), which combines the main advantages of previously studied molecules: high mechanical properties and relatively low processing temperatures [M. Laskoski, AR Shepherd, W. Mahzabeen, JS Clarke, TM Keller, U. Sorathia, Sustainable, fire-resistant phthalonitrile-based glass fiber composites, J. Polym. Sci. Part A Polym. Chem. 56 (2018) 1128-1132. doi: 10.1002 / pola.28989]. Glass cloth 6781 НТ sized 7781 E-glass was used as a reinforcing filler. The mixture for impregnation was prepared in acetone; 2.7 wt.% Was used as a hardener. % m-BASF. The fabric was laid out on aluminum foil, and the solution was manually spread over the fiber. The prepreg thus obtained was dried in air. PCM pre-curing was carried out in a heat press at a pressure of 3.45 bar and a temperature of 200 ° C. The pressing was carried out for the time required for the gelation of the binder and obtained from the rheological data. Post-curing was carried out in two stages in an oven at temperatures of 270 ° C and 375 ° C with holding for 6 h and 8 h, respectively. The porosity in the final PCM was no more than 3%. T _5% in air was 575 ° C, the modulus of elasticity was almost 5.5 GPa.

Methods known from the prior art for preparing prepregs, consisting in impregnating a reinforcing material with a binder solution, have a number of disadvantages, namely, with an increase in production volumes, requirements are imposed on working with flammable liquids, a lot of waste is generated that requires special disposal (solvents), costs are required for the purchase or regeneration solvents.

The prior art discloses a method of forming a composite based on cellulose (linen) fiber spun on a mat from Tex-Dem N.V. and thin films of epoxy resin HM 533 [I. Van de Weyenberg, T. Chi Truong, B. Vangrimde, I. Verpoest, Improving the properties of UD flax fiber reinforced composites by applying an alkaline fiber treatment, Compos. Part A Appl. Sci. Manuf. 37 (2006) 1368-1376. doi: 10.1016 / j.compositesa.2005.08.016.]. The scheme for obtaining a preform for PCM is shown in Fig. 2.

Curing of the obtained preform was carried out in an autoclave for 1 hour, a pressure of 3 bar and a temperature of 125 ° C. The mechanical properties of the obtained sample are presented in Table 2.

The described method makes it possible to obtain composites with low mechanical properties due to the low content of the reinforcing filler (40%) and the use of cellulose fiber as a reinforcing filler. In addition, the use of cellulose fiber reduces the moisture resistance of the composite, since cellulose actively swells in water and significantly loses strength. In addition, cellulose is biodegradable, which makes it impossible to use such materials in critical loaded structures, for example, in the aerospace industry or in capital construction. The use of carbon or glass fibers or fabrics will increase the strength and resistance of the materials to the external environment. The use of phthalonitrile matrices instead of epoxy ones will provide composites with high heat resistance.

Another method known from the prior art for preparing prepregs is to apply thin films of a binder to the fiber by pressing. So, in the work [N. Chatiras, P. Georgiopoulos, A. Christopoulos, E. Kontou, Thermomechanical characterization of basalt fiber reinforced biodegradable polymers, Polym. Compos. 40 (2019) 4340-4350. doi: 10.1002 / pc.25295] describes the use of two types of matrices: pure polylactic acid (PLA) and Ecovio (EC) - a commercial copolymer of polylactic acid and a polyester binder. As a reinforcing filler, we used fabric made of basalt fiber TVK-100, a tape made of basalt fiber BAS UNI 350, as well as glass fabric EC9. The prepreg was obtained by pressing a thin film of the rolled binder and fabric at a temperature of 180 ° C and a pressure of 15 MPa for 15 minutes. The mass content of the reinforcing filler in the obtained materials did not exceed 47%, the volume content - 29.2%, which is a significant drawback of such prepregs and does not allow obtaining PCM with high mechanical characteristics. For the obtained samples, the values of mechanical tensile and bending strength were obtained (Table 3).

Note: 1 - tensile strength, 2 - flexural strength

SEM micrographs were also obtained for the tested samples (Fig. 3). The pictures clearly show that the fiber is practically not impregnated with a binder.

Thus, solution-free processes for preparing prepregs are known in the art. However, by known methods prepregs were obtained with a low content of reinforcing fillers - no more than 40%, which is unnecessarily low and does not effectively redistribute the load between phases. Moreover, only cellulose and basalt fibers were used as reinforcing fillers, while the use of carbon fiber makes it possible to obtain materials with a lower density and, at the same time, higher mechanical characteristics.

A technical problem is the development of a method for preparing a prepreg with a phthalonitrile matrix without a solution. The prepreg obtained in this way can be used to obtain PCM with high temperature resistance for use in the aviation and space industries.

Disclosure of invention

The technical result of the claimed invention is the development of a solutionless method for preparing a prepreg, which makes it possible to obtain a PCM with an interlayer shear strength of 34.1-47.1 MPa, with a mass fraction of a binder of 30-40%. Also, the properties of the described materials are retained at 300 at least 90%, at 350-75%, at 400 - at least 50%, and the decomposition of the material (T _5% ) begins at a temperature of at least 500 ° C.

The technical result is achieved by the method of obtaining prepregs with phthalonitrile matrices, including the formation in a heat press of films with a thickness of 20-400 microns of low-melting phthalonitrile binders at a pressure of 2 to 10 bar and a temperature of 80 ° C to 140 ° C for 20-600 seconds, followed by applying the obtained films on a reinforcing filler at the rate of 35 ± 5 wt. % binder based on the weight of the reinforcing filler. In this case, a fabric or a tape made of glass or carbon fiber is used as a reinforcing filler, and low-melting phthalonitrile binders with glass transition temperatures not higher than 50 ° C are used as a binder, it is preferable to use binders formed from (1) the polymerizable mixture as phthalonitrile binders, including:

- one or more bis-phthalonitrile monomers selected from 1,3-bis- (3,4-dicyanophenoxy) benzene, 1,3-bis- (3,4-dicyanophenoxy) -2-fluorobenzene, 1,3-bis- (3,4-dicyanophenoxy) -4-fluorobenzene, 1,3-bis- (3,4-dicyanophenoxy) -2-chlorobenzene, 1,3-bis- (3,4-dicyanophenoxy) -4-chlorobenzene, 1, 3-bis- (3,4-dicyanophenoxy) -2-bromobenzene, 1,3-bis- (3,4-dicyanophenoxy) -4-bromobenzene, 1,3-bis- (3,4-dicyanophenoxy) -2, 4-difluorobenzene, 1,5-bis- (3,4-dicyanophenoxy) -2,4-dichlorobenzene, 1,3-bis- (3,4-dicyanophenoxy) -2-methylbenzene, more preferably 1,3-bis - (3,4-dicyanophenoxy) benzene, 1,3-bis- (3,4-dicyanophenoxy) -2-fluorobenzene, 1,3-bis- (3,4-dicyanophenoxy) -4-fluorobenzene, 1,3- bis- (3,4-dicyanophenoxy) -2,4-difluorobenzene, most preferably 1,3-bis- (3,4-dicyanophenoxy) benzene, in an amount of 20-94 wt. % of the mass of the polymerized mixture,

- one or more reactive flame retardant plasticizers selected from the group consisting of bis- (4-cyanophenoxy) -phenyl phosphate, bis- (3- (3,4-dicyanophenoxy) -phenyl phosphate, bis- (3- (3,4- dicyanophenoxy) -1-naphthylphosphate, bis- (4-cyanophenoxy) -phenylphosphonate, bis- (3- (3,4-dicyanophenoxy) phenyl) -phenylphosphonate, bis- (3- (3,4-dicyanophenoxy) phenyl) -isopropylphosphate , bis- (3- (3,4-dicyanophenoxy) phenyl) -butyl phosphate, bis- (3- (3,4-dicyanophenoxy) phenyl) -propargyl phosphate, bis- (4-cyanophenyl) phenyl phosphate, bis- (3-cyanophenoxy ) phenyl phosphate and bis-4- (3,4-dicyanophenoxy) phenyl) phenyl phosphate, more preferably from bis- (4-cyanophenoxy) phenyl phosphate, bis (3- (3,4-dicyanophenoxy) phenyl phosphate, bis (3 - (3,4-dicyanophenoxy) phenyl) -isopropyl phosphate, bis- (3- (3,4-dicyanophenoxy) phenyl) -butyl phosphate, taken in an amount of 5-80 wt.% Of the total weight of the polymerized mixture, and

- one or more active diluents selected from compounds of the group consisting of 4- [3- (dipropargylamino) phenoxy] phthalonitrile, 4- [4- (dipropargylamino) phenoxy] phthalonitrile, 4- (4-cyanophenoxy) -benzene-1, 2-dicarbonitrile, 4- (4-cyanophenoxy) phthalonitrile, 4- (3-cyanophenoxy) phthalonitrile and 4- (4-aminophenoxy) phthalonitrile, particularly preferably one or more compounds, 4- (4-cyanophenoxy) - benzene-1,2-dicarbonitrile, 4- [3- (dipropargylamino) phenoxy] phthalonitrile, 4- [4- (dipropargylamino) phenoxy] phthalonitrile, in an amount from 1 to 50% of the total weight of the polymerized mixture; and

(2) a polymerization initiator taken in an amount from 1 to 20% of the total weight of the polymerized mixture, selected from aromatic diamines or bisphenols having a boiling point under vacuum of 0.1 mm Hg. not less than 180 ° C, while the total content of the mixture to be polymerized and the polymerization initiator is from 60 to 100 wt. % of the total mass of the binder. Preferably, the polymerization initiator is selected from the group consisting of 1,3-bis- (4-aminophenoxy) benzene, 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, 3,3 '- [(2,3,5,6- tetrafluorobenz-1,4-diyl) bis (oxy)] dianiline, 4,4 '- [(2,3,5,6-tetrafluorobenz-1,4-diyl) bis (oxy)] dianiline, bis [4- ( 4-aminophenoxy) phenyl] sulfone or bisphenol A, most preferably from 1,3-bis (4-aminophenoxy) benzene or bis [4- (4-aminophenoxy) phenyl] sulfone.

Preferably, any films with a glass transition temperature above 130 ° C can be used as polymer release films, namely films made of polyethylene terephthalate, polyamide, polyimide, on which a release coating is applied to allow separation of the binder from the film.

The technical result is also achieved by a polymer composite material obtained by curing a prepreg with phthalonitrile matrices obtained by the above method. In this case, the obtained layered material is placed in a vacuum bag, the air is pumped out to vacuum values <1 mm Hg. and placed in a press, and curing is carried out according to the following regime: heating to 120-150 ° C at a rate of 2 ± 0.5 ° C / min and contact pressure (1 ± 0.2 bar), followed by heating to 180 ± 2 ° C at a speed of 2 ± 0.5 ° C / min and a pressure of 2-8 bar, followed by a rise in pressure to 10 ± 0.5 bar and holding at this temperature for 8 ± 0.1 h. After that, the composite is removed from the mold and post-cured at 330 ± 5 ° C for 8 ± 0.1 h in a free form. Hot samples are cooled, without being removed from the oven, to room temperature at a cooling rate of not more than 5 ° C / min. The polymer composite material obtained in this way has an interlayer shear strength of 34.1-47.1 MPa, a compressive strength of 463.0-662.9 MPa, and an elastic modulus of 27.2-55.3 GPa.

Brief Description of Drawings

The invention is illustrated by the following drawings.

FIG. 1 is a SEM micrograph of (a) NLPN-1, (b) NLPN-2, (c) NLPN-3 (d) NLPN-4.

FIG. 2 shows a diagram of the preparation of carbon fiber laminates with a phthalonitrile binder solution.

FIG. 3 shows a SEM micrograph of a PCM sample after testing.

demonstrates the mechanical characteristics of composites.

FIG. 4 shows A - diagram of prepreg preparation by direct application, B - diagram of prepreg pressing.

FIG. 5 is a SEM micrograph of the obtained PCM (Comparative Example 5).

Implementation of the invention

Below is a more detailed description of the claimed invention. The present invention can be subject to various changes and modifications, which will be understood by a person skilled in the art based on reading this description. For example, the specific brand of phthalonitrile binder (a necessary feature is a glass transition temperature of less than 50 ° C) used to obtain thin films, the type of reinforcing filler (can be based on carbon, glass, basalt, aramid or any other type of fiber) and its shape textile processing (fabrics of various weaves, unidirectional tapes), auxiliary materials used (separating films), a method of distributing a binder to obtain a thin film.

All reagents used are commercially available, all procedures, unless otherwise stated, were carried out at room temperature or ambient temperature, that is, in the range from 18 to 25 ° C.

To obtain prepreg samples, the method of direct application of thin films of the binder directly to the fabric or tape was chosen. To obtain binder films, a Langzauner LZT-L 250 heat press is used. The maximum possible supported temperature of the plates of the press working zone is 400 ° C, the maximum pressure is 20 bar. For the implementation of the invention, such characteristics are excessive and any heated press, which can maintain a temperature of the working zone of at least 180 ° C and a pressure of 10 bar, is suitable. For the preparation of prepregs used binders described in RU 2695606, and having a glass transition temperature of less than 50 ° C, formed from (1) a polymerizable mixture, including:

- one or more bis-phthalonitrile monomers selected from 1,3-bis- (3,4-dicyanophenoxy) benzene, 1,3-bis- (3,4-dicyanophenoxy) -2-fluorobenzene, 1,3-bis- (3,4-dicyanophenoxy) -4-fluorobenzene, 1,3-bis- (3,4-dicyanophenoxy) -2-chlorobenzene, 1,3-bis- (3,4-dicyanophenoxy) -4-chlorobenzene, 1, 3-bis- (3,4-dicyanophenoxy) -2-bromobenzene, 1,3-bis- (3,4-dicyanophenoxy) -4-bromobenzene, 1,3-bis- (3,4-dicyanophenoxy) -2, 4-difluorobenzene, 1,5-bis- (3,4-dicyanophenoxy) -2,4-dichlorobenzene, 1,3-bis- (3,4-dicyanophenoxy) -2-methylbenzene, more preferably 1,3-bis - (3,4-dicyanophenoxy) benzene, 1,3-bis- (3,4-dicyanophenoxy) -2-fluorobenzene, 1,3-bis- (3,4-dicyanophenoxy) -4-fluorobenzene, 1,3- bis- (3,4-dicyanophenoxy) -2,4-difluorobenzene, most preferably 1,3-bis- (3,4-dicyanophenoxy) benzene, in an amount of 20-94 wt. % of the mass of the polymerized mixture,

- one or more reactive flame retardant plasticizers selected from the group consisting of bis- (4-cyanophenoxy) -phenyl phosphate, bis- (3- (3,4-dicyanophenoxy) -phenyl phosphate, bis- (3- (3,4- dicyanophenoxy) -1 -naphthylphosphate, bis- (4-cyanophenoxy) -phenylphosphonate, bis- (3- (3,4-dicyanophenoxy) phenyl) -phenylphosphonate, bis- (3- (3,4-dicyanophenoxy) phenyl) -isopropylphosphate , bis- (3- (3,4-dicyanophenoxy) phenyl) -butyl phosphate, bis- (3- (3,4-dicyanophenoxy) phenyl) -propargyl phosphate, bis- (4-cyanophenyl) phenyl phosphate, bis- (3-cyanophenoxy ) phenyl phosphate and bis-4- (3,4-dicyanophenoxy) phenyl) phenyl phosphate, more preferably from bis- (4-cyanophenoxy) phenyl phosphate, bis (3- (3,4-dicyanophenoxy) phenyl phosphate, bis (3 - (3,4-dicyanophenoxy) phenyl) -isopropyl phosphate, bis- (3- (3,4-dicyanophenoxy) phenyl) -butyl phosphate, taken in an amount of 5-80 wt.% Of the total weight of the polymerized mixture, and

- one or more active diluents selected from compounds of the group consisting of 4- [3- (dipropargylamino) phenoxy] phthalonitrile, 4- [4- (dipropargyl amino) phenoxy] phthalonitrile, 4- (4-cyanophenoxy) -benzene-1 , 2-dicarbonitrile, 4- (4-cyanophenoxy) phthalonitrile, 4- (3-cyanophenoxy) phthalonitrile and 4- (4-aminophenoxy) phthalonitrile, particularly preferably from one or more compounds, 4- (4-cyanophenoxy) -benzene-1,2-dicarbonitrile, 4- [3- (dipropargyl amino) phenoxy] phthalonitrile, 4- [4- (dipropargylamino) phenoxy] phthalonitrile, in an amount from 1 to 50% of the total weight of the polymerized mixture; and

(2) a polymerization initiator taken in an amount from 1 to 20% of the total weight of the polymerized mixture, selected from aromatic diamines or bisphenols having a boiling point under vacuum of 0.1 mm Hg. not less than 180 ° C, while the total content of the mixture to be polymerized and the polymerization initiator is from 60 to 100 wt. % of the total mass of the binder. Preferably, the polymerization initiator is selected from the group consisting of 1,3-bis- (4-aminophenoxy) benzene, 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, 3,3 '- [(2,3,5,6- tetrafluorobenz-1,4-diyl) bis (oxy)] dianiline, 4,4 '- [(2,3,5,6-tetrafluorobenz-1,4-diyl) bis (oxy)] dianiline, bis [4- ( 4-aminophenoxy) phenyl] sulfone or bisphenol A, most preferably from 1,3-bis (4-aminophenoxy) benzene or bis [4- (4-aminophenoxy) phenyl] sulfone.

Manufacturing was carried out according to the following procedure:

In a press preheated to 80-120 ° C, between two anti-adhesive polymer films, a finely ground binder powder is evenly distributed by any method known from the prior art, the particle size of which lies in the range of 50-1000 μm. The thickness of the powder layer should not exceed ten particle diameters. Press plates are brought together under a pressure of 2-10 bar. The binder is held from 20 sec to 600 sec and removed from the press in the form of a film. The hot samples are placed on a flat surface and allowed to cool to room temperature. The resulting films can be stored indefinitely at room temperature. It should be borne in mind that at temperatures below the glass transition temperature (<21 ° C), the film becomes more fragile and rough physical impact can lead to its destruction.

Any films with a glass transition temperature above 130 ° C, for example, polyethylene terephthalate (PET), polyamide, polyimide and others, can be used as polymer separating films. It should be borne in mind that the film must be coated with a release coating to allow the separation of the binder from the film, which can be used as various silicones.

The prepreg sheets were made by direct application (FIG. 4A). On one side of the thin film of binder, a release film sheet was peeled off. A binder film was placed on a sheet of reinforcing fabric (carbon or glass fabric) so that the binder was between the second release film and the reinforcing fabric. The binder sheet through the film was evenly smoothed onto the reinforcing fabric with the force necessary to adhere the binder and enable the release film to be released without effort. The release film was removed from the binder. If the size of the reinforcing fabric is larger than the size of the binder film, then pieces of a thin binder film of comparable size were manually placed on the remaining uncovered areas of the reinforcing fabric. The application was controlled by the previously known weight of the thin film of the binder and amounted to 35 ± 5% of the total weight of the reinforcing filler, the film with a thickness of 100-300 μm is applied to the reinforcing filler in the form of a cloth or tape made of carbon or glass fiber. At room temperature, prepreg can be stored indefinitely.

The prepared prepreg sheets are placed inside a silicone frame with similar linear dimensions and a thickness of at least 5 mm (Fig. 4B). The number of layers of carbon fabric or fiberglass alternating with films for the manufacture of a PCM plate depends on the required thickness of the PCM. Since for measuring the mechanical tensile strength in accordance with GOST R 56785, the thickness of the measured sample should be 2 ± 0.2 mm, the PCM platinum was made from ten layers of carbon fabric (monolayer thickness 0.2 mm), or from eight layers of fiberglass (monolayer thickness 0 , 25 mm) of which all layers, except one, were with a binder applied, and the topmost layer was a fabric without a binder. From above, prepreg sheets are covered with a metal plate (tsulaga) with linear dimensions similar to prepregs and at least 2 mm thick to ensure uniform loading over the entire surface of the composite. Drainage was laid on top of the structure to facilitate air pumping, which can be any fibrous or mesh polymer materials.

A vacuum bag is collected around the tooling, the air is evacuated to vacuum values <1 mm Hg. The molding of the composite is carried out in a heat press (maximum maintained temperature 400 ° C, pressure - 20 bar) according to the following program: heating to 120-150 ° C at a press pressure of 1 ± 0.2 bar =>, and as soon as the set parameters are reached, we immediately start further pressure increase up to 4-8 bar, heating up to 180 ± 2 ° С at a rate of 2 ± 0.5 ° С / min => pressure increase up to 10 ± 0.5 bar, holding at 180 ± 2 ° С for 8 ± 0 , 1 h. After that, the composite was removed from the mold and post-cured at 330 ± 5 ° C in free form. Hot samples are cooled, without being removed from the oven, to room temperature at a cooling rate of not more than 5 ° C / min. It is preferable to assemble a blank for the manufacture of a PCM plate (prepreg + drainage + vacuum bag with vacuum) immediately before pressing, however, if the structure is assembled well, then it can be stored for several days in this form, the main thing is that the vacuum is maintained before being installed in the press.

Below are specific examples of implementation, which are not the only possible, but demonstrates the possibility of achieving the required technical result.

Getting the binder composition:

Binder ФН1 (PNT).

A 2 L glass reactor equipped with a mechanical stirrer was charged with 250 g of 1,3-bis (3,4-dicyanophenoxy) benzene. The reactor was heated to 170 ° C to melt the binder, after which stirring and vacuum (1 mm Hg) were turned on. The bis (3-cyanophenoxy) phenyl phosphate melt (150 g) was added slowly in small portions as it dissolved. The container was cooled to 140 ° C. To the resulting melt were added 100 g of 4- (4-aminophenoxy) phthalonitrile and 25 g of 1,3-bis- (3-aminophenoxy) benzene, followed by stirring at 100 ° C for 15 minutes. After that, the mixture was poured onto a metal plate, allowed to cool, and a green glassy mass was obtained. T _c = 22 ° C.

Binder FN2 (PNX).

In a 2 L glass reactor equipped with a mechanical stirrer, 475 g of 1,3-bis (3,4-dicyanophenoxy) benzene was charged. The vessel was heated to 190 ° C to melt the monomer, after which stirring was started. Powder of 4- (4-aminophenoxy) phthalonitrile (25 g) was added slowly, and then a melt of 100 g of bis (3- (3,4-dicyainophenoxy) phenyl) propargyl phosphate, preheated to 170 ° C, was added. The mixture was cooled to 160 ° C, and 30 g of APB 1,3-bis (4-aminophenoxy) benzene was added to the resulting melt and stirred at 160 ° C for 15 minutes. After that, the mixture was poured onto a metal plate, allowed to cool, and a green glassy mass was obtained. T _c = 42 ° C

Binder FN1-P1 (PNT-P1).

660 g of FN-1 was loaded into a glass reactor, a vacuum (1 mm Hg) was applied to the system for degassing, heating was switched on to 130 ° C and the substance began to melt, after which stirring was switched on at 6-10 rpm, gradually increasing the rotation speed as the substance melted to 120 rpm, stirred for 20 minutes. Then 26.4 g of Aerosil R202 was added to the melt in portions with stirring. After each iteration of the introduction, we waited for the distribution of Aerosil R202 in the volume of the melt and for the mixture to reach a predetermined temperature regime of 130 ° C. When all Aerosil R202 was added, the vacuum was turned on and the stirring speed was increased to maximum. Stirring was continued for 20 min. The stirring was stopped and the melt was poured into a metal mold. After cooling of the binder, a monolithic glassy mass of dark green color was obtained.

Binder FN2-P1 (PNX-P1).

660 g of FN-2 was loaded into a glass reactor, a vacuum (1 mm Hg) was applied to the system for degassing, heating was switched on to 130 ° C and the substance began to melt, after which stirring was switched on at 6-10 rpm, gradually increasing the rotation speed as the substance melted to 120 rpm, stirred for 20 minutes. Then 26.4 g of Aerosil R202 was added to the melt in portions with stirring. After each iteration of the introduction, we waited for the distribution of Aerosil R202 in the volume of the melt and for the mixture to reach a predetermined temperature regime of 130 ° C. When all Aerosil R202 was added, the vacuum was turned on and the stirring speed was increased to maximum. Stirring was continued for 20 min. The stirring was stopped and the melt was poured into a metal mold. After cooling of the binder, a monolithic glassy mass of dark green color was obtained.

Binder FN1-P2 (PNT-P2).

660 g of FN-1 was loaded into the reactor, a vacuum (1 mm Hg) was applied to the system for degassing, heating was switched on to 130 ° C and the substance began to melt, after which stirring was switched on at 6-10 rpm, gradually increasing rotation speed as the substance melts up to 120 rpm, was stirred for 20 minutes. After melting the binder, 440 g of quartz flour was added in portions with stirring. After each iteration of the introduction, the distribution of flour in the volume of the melt and the exit of the mixture to a given temperature regime of 130 ° C were expected. When all the flour was added, the vacuum was turned on and the stirring speed was increased to 180 rpm. Stirring was continued for 20 min. The stirring was stopped and the melt was poured into a metal mold. After cooling of the binder, a loose glassy mass of light green color was obtained.

Binder FN2-P2 (PNX-P2)

The reactor was loaded with 660 g of FN-2, a vacuum (1 mm Hg) was applied to the system for degassing, heating was switched on to 130 ° C and the substance began to melt, after which stirring was switched on at 6-10 rpm, gradually increasing rotation speed as the substance melts up to 120 rpm, was stirred for 20 minutes. After melting the binder, 440 g of quartz flour was added in portions with stirring. After each iteration of the introduction, the distribution of flour in the volume of the melt and the exit of the mixture to a given temperature regime of 130 ° C were expected. When all the flour was added, the vacuum was turned on and the stirring speed was increased to 180 rpm. Stirring was continued for 20 min. The stirring was stopped and the melt was poured into a metal mold. After cooling of the binder, a loose glassy mass of light green color was obtained.

Obtaining thin films of the binder:

Example 1

In a Langzauner LZT-L 250 thermopress preheated to 80 ° C, a release film with an anti-adhesive coating TU 5459-055-39160180-00 400 × 400 mm ^{2 was} placed. On the film, 15 g of binder FN1 (PNT) finely ground to a size of 400 μm was evenly placed in the center, leveled with a spatula. The top of the binder was covered with a similar release film. The press plates were brought together under a pressure of 2 bar. After 600 seconds (10 minutes) the press plates were parted and the finished binder film 300 μm thick was removed.

Example 2

In a Langzauner LZT-L 250 thermopress preheated to 90 ° C, a release film with a release coating TU 5459-055-39160180-00 400 × 400 mm ^{2 was} placed. On the film, 15 g of binder FN1 (PNT) finely ground to a size of 350 μm was evenly placed in the center and leveled with a spatula. The top of the binder was covered with a similar release film. The press plates were brought together under a pressure of 2 bar. After 480 seconds (8 minutes) the press plates were parted and the finished binder film 285 μm thick was removed.

Example 3

A film with an anti-adhesive coating TU 5459-055-39160180-00 400 × 400 mm ² in size was placed in a Langzauner LZT-L 250 thermopress preheated to 100 ° C. On the film, 15 g of binder FN1 (PNT) finely ground to a size of 300 μm was evenly placed in the center and leveled with a spatula. The top of the binder was covered with a similar film. The press plates were brought together under a pressure of 2 bar. After 300 seconds (5 minutes), the press plates were parted and the finished binder film, 255 μm thick, was removed.

Example 4

A film with an anti-adhesive coating TU 5459-055-39160180-00 400 × 400 mm2 in size was placed into a Langzauner LZT-L 250 thermopress preheated to 110 ° C. On the film, 15 g of binder FN1 (PNT) finely ground to a size of 200 μm was evenly placed in the center, leveled with a spatula. The top of the binder was covered with a similar film. The press plates were brought together under a pressure of 2 bar. After 240 seconds (4 minutes) the press plates were parted and the finished binder film 180 μm thick was removed.

Example 5

A film with an anti-adhesive coating TU 5459-055-39160180-00 400 × 400 mm2 in size was placed in a Langzauner LZT-L 250 heat press preheated to 120 ° C. On the film, 15 g of binder FN1 (PNT) finely ground to a size of 800 μm was evenly placed in the center, leveled with a spatula. The top of the binder was covered with a similar film. The press plates were brought together under a pressure of 2 bar. After 180 seconds (3 minutes) the press plates were parted and the finished binder film of 175 µm thickness was removed.

Example 6

A film with a release coating TU 5459-055-39160180-00 400 × 400 mm2 in size was placed in a Langzauner LZT-L 250 thermopress preheated to 130 ° C. On the film, 15 g of binder FN1 (PNT) finely ground to a size of 500 μm was evenly placed in the center, and leveled with a spatula. The top of the binder was covered with a similar film. The press plates were brought together under a pressure of 2 bar. After 120 seconds (2 minutes), the press plates were parted and the finished binder film 120 μm thick was removed.

Example 7

A film with an anti-adhesive coating TU 5459-055-39160180-00 400 × 400 mm2 in size was placed in a Langzauner LZT-L 250 thermopress preheated to 140 ° C. On the film, 15 g of binder FN1 (PNT) finely ground to a size of 950 μm was evenly placed in the center and leveled with a spatula. The top of the binder was covered with a similar film. The press plates were brought together under a pressure of 2 bar. After 20 seconds, the press plates were parted and the finished binder film 100 μm thick was removed.

Example 8

A film with an anti-adhesive coating TU 5459-055-39160180-00 400 × 400 mm2 in size was placed into a Langzauner LZT-L 250 thermopress preheated to 100 ° C. On the film, 15 g of binder FN1 (PNT) finely ground to a size of 300 μm was evenly placed in the center and leveled with a spatula. The top of the binder was covered with a similar film. The press plates were brought together at a pressure of 4 bar. After 240 seconds (4 minutes) the press plates were parted and the finished binder film was removed with a thickness of 200 microns.

Example 9

A film with an anti-adhesive coating TU 5459-055-39160180-00 400 × 400 mm2 in size was placed into a Langzauner LZT-L 250 thermopress preheated to 100 ° C. On the film, 15 g of binder FN1 (PNT) finely ground to a size of 400 μm was evenly placed in the center, leveled with a spatula. The top of the binder was covered with a similar film. The press plates were brought together under a pressure of 6 bar. After 180 seconds (3 minutes) the press plates were parted and the finished binder film 180 μm thick was removed.

Example 10

A film with an anti-adhesive coating TU 5459-055-39160180-00 400 × 400 mm2 in size was placed into a Langzauner LZT-L 250 thermopress preheated to 100 ° C. On the film, 15 g of binder FN1 (PNT) finely ground to a size of 350 μm was evenly placed in the center and leveled with a spatula. The top of the binder was covered with a similar film. The press plates were brought together at a pressure of 8 bar. After 120 seconds (2 minutes) the press plates were parted and the finished binder film, 165 μm thick, was removed.

Example 11

A film with an anti-adhesive coating TU 5459-055-39160180-00 400 × 400 mm2 in size was placed into a Langzauner LZT-L 250 thermopress preheated to 100 ° C. On the film, 15 g of binder FN1 (PNT) finely ground to a size of 250 μm was evenly placed in the center, leveled with a spatula. The top of the binder was covered with a similar film. The press plates were brought together under a pressure of 10 bar. After 60 seconds (1 minute), the press plates were parted and the finished binder film, 140 μm thick, was removed.

Example 12

A film with an anti-adhesive coating TU 5459-055-39160180-00 400 × 400 mm2 in size was placed into a Langzauner LZT-L 250 thermopress preheated to 100 ° C. On the film, 15 g was evenly placed in the center. Binder FN2 (PNX), finely ground to a size of 400 μm, was leveled with a spatula. The top of the binder was covered with a similar film. The press plates were brought together at a pressure of 4 bar. After 240 seconds (4 minutes) the press plates were parted and the finished binder film was removed with a thickness of 195 microns.

Example 13

A film with an anti-adhesive coating TU 5459-055-39160180-00 400 × 400 mm2 in size was placed into a Langzauner LZT-L 250 thermopress preheated to 100 ° C. On the film, 15 g of binder FN1-P1 (PNT-P1) finely ground to a size of 500 μm was evenly placed in the center, leveled with a spatula. The top of the binder was covered with a similar film. The press plates were brought together at a pressure of 4 bar. After 240 seconds (4 minutes) the press plates were parted and the finished binder film 220 μm thick was removed.

Example 14

A film with an anti-adhesive coating TU 5459-055-39160180-00 400 × 400 mm2 in size was placed into a Langzauner LZT-L 250 thermopress preheated to 100 ° C. On the film, 15 g of binder FN1-P2 (PNT-P2) finely ground to a size of 400 μm was evenly placed in the center, leveled with a spatula. The top of the binder was covered with a similar film. The press plates were brought together at a pressure of 4 bar. After 240 seconds (4 minutes), the press plates were parted and the finished binder film 220 μm thick was removed.

Example 15

A film with an anti-adhesive coating TU 5459-055-39160180-00 400 × 400 mm2 in size was placed into a Langzauner LZT-L 250 thermopress preheated to 100 ° C. On the film, 15 g of binder FN2-P1 (PNX-P1) finely ground to a size of 300 μm was evenly placed in the center, leveled with a spatula. The top of the binder was covered with a similar film. The press plates were brought together at a pressure of 4 bar. After 240 seconds (4 minutes) the press plates were parted and the finished binder film was removed with a thickness of 225 μm.

Example 16

A film with an anti-adhesive coating TU 5459-055-39160180-00 400 × 400 mm2 in size was placed into a Langzauner LZT-L 250 thermopress preheated to 100 ° C. On the film, 15 g of FN2-P2 (PNX-P2) binder finely ground to a size of 300 μm was evenly placed in the center, leveled with a spatula. The top of the binder was covered with a similar film. The press plates were brought together at a pressure of 4 bar. After 240 seconds (4 minutes) the press plates were parted and the finished binder film 180 μm thick was removed.

Assembling a workpiece for PCM:

Example 17

A silicone frame with dimensions 350 × 350 × 5 mm ³ with a cut-out cavity in the center measuring 300 × 300 mm ^{2 was} placed on a metal tooling measuring 450 × 550 × 4 mm ³ . A release film sheet was peeled off one side of the binder thin film. On a sheet of carbon fabric 22502, manufactured by ITECMA, a 2 × 2 twill weave of 3k HTA40 carbon fiber manufactured by TohoTenax of the Teijin group of companies, 300 × 300 mm ^{2 was} placed with a film of binder so that the binder was between the second release film and the reinforcing fabric ... The binder sheet was evenly smoothed onto the reinforcing fabric with a roller through the film. The release film was removed from the binder. On the remaining uncovered areas of the reinforcing fabric, comparable in size pieces of the binder film obtained according to examples 1-16 were manually laid. Thus, 9 layers of solution-free prepreg were made. Since 10 layers of fabric weighed 180 g, the mass of the binder films taken to form nine layers of prepreg was 120 g. This corresponds to the calculated amount of matrix in the PCM 40%. The prepreg was placed inside the silicone frame so that the layer of applied binder on each of the layers was on top. On top of nine layers of prepreg, a sheet of carbon fabric with dimensions of 300 × 300 mm ^{2 was} laid, and then a metal plate with dimensions of 300 × 300 × 2 mm ^{2 was} laid. A layer of drainage material Nialon® IP 340 A with dimensions 450 × 550 mm ^{2 was} laid on top. The structure was placed in a vacuum bag, from where air was evacuated to values <1 mm Hg. A description of a possible mode of forming a PCM from this workpiece is described below in the examples Example-Example.

Example 18

A silicone frame with dimensions 350 × 350 × 5 mm ³ with a cut-out cavity in the center measuring 300 × 300 mm ^{2 was} placed on a metal tooling measuring 450 × 550 × 4 mm ³ . A release film sheet was peeled off one side of the binder thin film. On a sheet of glass cloth, grade T-10, produced by the Polotsk-glass fiber company, with a size of 300 × 300 mm ^2, a binder film was placed so that the binder was between the second separating film and the reinforcing fabric. The binder sheet was evenly smoothed onto the reinforcing fabric with a roller through the film. The release film was removed from the binder. On the remaining uncovered areas of the reinforcing fabric, comparable in size pieces of the binder film obtained according to examples 1-16 were manually laid. In this way, 7 layers of solution-free prepreg were made. Since 8 layers of fabric weighed 230 g, the mass of the binder films taken to form seven layers of prepreg was 98.6 g. This corresponds to the calculated amount of matrix in the PCM 30%. The prepreg was placed inside the silicone frame so that the layer of applied binder on each of the layers was on top. On top of seven layers of prepreg, a sheet of glass cloth with dimensions of 300 × 300 mm ^{2 was} laid, and then a metal plate with dimensions of 300 × 300 × 2 mm ^{2 was} laid. A layer of drainage material Nialon® IP 340 A with dimensions 450 × 550 mm ^{2 was} laid on top. The structure was placed in a vacuum bag, from where air was evacuated to values <1 mm Hg. A description of a possible mode of forming a PCM from this workpiece is described below in the examples Example-Example.

Examples of obtaining PCM

Example 19

A vacuum bag with a PCM blank was placed in an unheated Langzauner LZT-L 250 heat press. The press plates were brought together at a pressure of 1 bar. The preform was heated to a temperature of 120 ° C at a rate of 2 ° C / min, after which the pressure rose to 4 bar. Further, heating was carried out to a temperature of 180 ° C at a rate of 2 ° C / min. After reaching this temperature, the pressure was increased to 10 bar and held at 180 ° C for 8 hours. The composite was then removed from the mold and post-cured at 330 ° C in a free form. Hot samples are cooled without taking them out of the oven to room temperature with a cooling rate of 5 ° C / min. Received PCM with a binder content of 39%.

Example 20

A vacuum bag with a PCM blank was placed in an unheated heat press Langzauner LZT-L 250. The press plates were brought together at a pressure of 1 bar. The preform was heated to a temperature of 130 ° C at a rate of 2 ° C / min, after which the pressure was raised to 4 bar. Further, heating was carried out to a temperature of 180 ° C at a rate of 2 ° C / min. After reaching this temperature, the pressure was increased to 10 bar and held at 180 ° C for 8 hours. The composite was then removed from the mold and post-cured at 330 ° C in a free form. Hot samples are cooled without taking them out of the oven to room temperature at a cooling rate of 3 ° C / min. Received PCM with a binder content of 37%.

Example 21

A vacuum bag with a PCM blank was placed in an unheated Langzauner LZT-L 250 heat press. The press plates were brought together at a pressure of 1 bar. The preform was heated to a temperature of 140 ° C at a rate of 2 ° C / min, after which the pressure was raised to 4 bar. Further, heating was carried out to a temperature of 180 ° C at a rate of 2 ° C / min. After reaching this temperature, the pressure was increased to 10 bar and held at 180 ° C for 8 hours. The composite was then removed from the mold and post-cured at 330 ° C in a free form. Hot samples are cooled without taking them out of the oven to room temperature at a cooling rate of 2 ° C / min. Received PCM with a binder content of 37%.

Example 22

A vacuum bag with a PCM blank was placed in an unheated Langzauner LZT-L 250 heat press. The press plates were brought together under contact pressure. The preform was heated to a temperature of 150 ° C at a rate of 2 ° C / min, after which the pressure was raised to 4 bar. Further, heating was carried out to a temperature of 180 ° C at a rate of 2 ° C / min. After reaching this temperature, the pressure was increased to 10 bar and held at 180 ° C for 8 hours. The composite was then removed from the mold and post-cured at 330 ° C in a free form. Hot samples are cooled without taking them out of the oven to room temperature at a cooling rate of 4 ° C / min. Received PCM with a binder content of 36%.

Example 23

A vacuum bag with a PCM blank was placed in an unheated Langzauner LZT-L 250 heat press. The press plates were brought together at a pressure of 1 bar. The preform was heated to a temperature of 120 ° C at a rate of 2 ° C / min, after which the pressure was raised to 6 bar. Further, heating was carried out to a temperature of 180 ° C at a rate of 2 ° C / min. After reaching this temperature, the pressure was increased to 10 bar and held at 180 ° C for 8 hours. The composite was then removed from the mold and post-cured at 330 ° C in a free form. Hot samples are cooled without taking them out of the oven to room temperature at a cooling rate of 1 ° C / min. Received PCM with a binder content of 37%.

Example 24

A vacuum bag with a PCM blank was placed in an unheated Langzauner LZT-L 250 heat press. The press plates were brought together at a pressure of 1 bar. The preform was heated to a temperature of 120 ° C at a rate of 2 ° C / min, after which the pressure was raised to 8 bar. Further, heating was carried out to a temperature of 180 ° C at a rate of 2 ° C / min. After reaching this temperature, the pressure was increased to 10 bar and held at 180 ° C for 8 hours. The composite was then demolded and post-cured at 330 ° C in a free form. Hot samples are cooled, without being removed from the oven, to room temperature at a cooling rate of 5 ° C / min. Received PCM with a binder content of 35%. Example 25

A vacuum bag with a PCM blank was placed in an unheated Langzauner LZT-L 250 heat press. The press plates were brought together at a pressure of 1 bar. The preform was heated to a temperature of 130 ° C at a rate of 2 ° C / min, after which the pressure was raised to 6 bar. Further, heating was carried out to a temperature of 180 ° C at a rate of 2 ° C / min. After reaching this temperature, the pressure was increased to 10 bar and held at 180 ° C for 8 hours. The composite was then removed from the mold and post-cured at 330 ° C in a free form. Hot samples are cooled without taking them out of the oven to room temperature at a cooling rate of 2 ° C / min. Received PCM with a binder content of 35%.

Example 26

A vacuum bag with a PCM blank was placed in an unheated Langzauner LZT-L 250 heat press. The press plates were brought together at a pressure of 1 bar. The preform was heated to a temperature of 130 ° C at a rate of 2 ° C / min, after which the pressure was raised to 8 bar. Further, heating was carried out to a temperature of 180 ° C at a rate of 2 ° C / min. After reaching this temperature, the pressure was increased to 10 bar and held at 180 ° C for 8 hours. The composite was then removed from the mold and post-cured at 330 ° C in a free form. Hot samples are cooled without taking them out of the oven to room temperature at a cooling rate of 4 ° C / min. Received PCM with a binder content of 33%.

Example 27

A vacuum bag with a PCM blank was placed in an unheated Langzauner LZT-L 250 heat press. The press plates were brought together at a pressure of 1 bar. The preform was heated to a temperature of 140 ° C at a rate of 2 ° C / min, after which the pressure was raised to 6 bar. Further, heating was carried out to a temperature of 180 ° C at a rate of 2 ° C / min. After reaching this temperature, the pressure was increased to 10 bar and held at 180 ° C for 8 hours. The composite was then removed from the mold and post-cured at 330 ° C in a free form. Hot samples are cooled without taking them out of the oven to room temperature at a cooling rate of 1 ° C / min. Received PCM with a binder content of 36%.

Example 28

A vacuum bag with a PCM blank was placed in an unheated Langzauner LZT-L 250 heat press. The press plates were brought together at a pressure of 1 bar. The preform was heated to a temperature of 140 ° C at a rate of 2 ° C / min, after which the pressure was raised to 8 bar. Further, heating was carried out to a temperature of 180 ° C at a rate of 2 ° C / min. After reaching this temperature, the pressure was increased to 10 bar and held at 180 ° C for 470 minutes. Thereafter, the composite was removed from the mold and post-cured at 330 ° C for 470 min in a free form. Hot samples are cooled without taking them out of the oven to room temperature at a cooling rate of 2 ° C / min. Received PCM with a binder content of 37%.

Example 29

A vacuum bag with a PCM blank was placed in an unheated Langzauner LZT-L 250 heat press. The press plates were brought together at a pressure of 1 bar. The preform was heated to a temperature of 150 ° C at a rate of 2 ° C / min, after which the pressure was raised to 6 bar. Further, heating was carried out to a temperature of 180 ° C at a rate of 2 ° C / min. After reaching this temperature, the pressure was increased to 10 bar and held at 180 ° C for 8 hours. The composite was then demolded and post-cured at 330 ° C for 8 hours in a free form. Hot samples are cooled without taking them out of the oven to room temperature at a cooling rate of 3 ° C / min. Received PCM with a binder content of 32%.

Example 30

A vacuum bag with a PCM blank was placed in an unheated Langzauner LZT-L 250 heat press. The press plates were brought together at a pressure of 1 bar. The preform was heated to a temperature of 150 ° C at a rate of 2 ° C / min, after which the pressure was raised to 8 bar. Further, heating was carried out to a temperature of 180 ° C at a rate of 2 ° C / min. After reaching this temperature, the pressure was increased to 10 bar and held at 180 ° C for 8 hours. The composite was then demolded and post-cured at 330 ° C for 490 minutes in a free state. Hot samples are cooled without taking them out of the oven to room temperature at a cooling rate of 3 ° C / min. Received PCM with a binder content of 31%.

The results of mechanical tests of PCM samples are given in table. 4 and 5.

Comparative Example 31

A TU 5459-055-39160180-00 release film with a 400 × 400 mm ² anti-adhesive coating was placed in a Langzauner LZT-L 250 thermopress preheated to 70 ° C. On the film, 15 g of PNT-P1 binder (OOO Itekma), finely ground to a size of 800 μm, was evenly placed in the center, leveled with a spatula. The top of the binder was covered with a similar film. The press plates were brought together under a pressure of 2 bar. After 600 seconds (10 minutes), the press plates were parted. The binder was a thick layer (1.5 mm) with a low radius. It is not possible to use a thermoplastic to form a prepreg in this form. Comparative example 32.

A film with an anti-adhesive coating TU 5459-055-39160180-00 400 × 400 mm2 in size was placed in a thermopress preheated to 150 ° C. On the film, 15 g was evenly placed in the center. binder PNT-P1 finely ground to a size of 300 μm, leveled with a spatula. The top of the binder was covered with a similar film. The press plates were brought together under a pressure of 2 bar. After 10 seconds, the binder started to flow out of the press.

Comparative example 33.

A film with an anti-adhesive coating TU 5459-055-39160180-00 400 × 400 mm2 in size was placed into a Langzauner LZT-L 250 thermopress preheated to 80 ° C. On the film, 15 g was evenly placed in the center. PNT binder, finely ground to a size of 900 μm, was leveled with a spatula. The top of the binder was covered with a similar film. The press plates were brought together under a pressure of 2 bar. After 20 seconds, the press plates were divorced. The binder was a thick, low radius (1.7 mm) slab. It is not possible to use a thermoplastic to form a prepreg in this form.

Comparative example 34

A vacuum bag with a PCM blank from example 17 was placed in an unheated heat press Langzauner LZT-L 250. The press plates were brought together at a pressure of 1 bar. The preform was heated to a temperature of 180 ° C at a rate of 2 ° C / min, after which the pressure was increased to 4 bar, and held at 180 ° C for 8 hours. After that, the composite was removed from the mold. Received PCM with a binder content of 40%. Analysis of SEM micrographs showed a high void content in the finished material.

Comparative Example 35

A vacuum bag with a PCM preform from Example 17 was placed into a Langzauner LZT-L 250 heat press heated to 180 ° C. The press plates were brought together at a pressure of 10 bar and held at 180 ° C for 8 hours. After that, the composite was removed from the mold. Received PCM with a binder content of 39%. Analysis of SEM photomicrographs showed a high void content in the finished material (Fig. 5).

Thus, failure to comply with the mode of pressing thin films of the binder leads either to obtaining samples that are too thick in the case of low temperatures, or to leakage of the binder beyond the boundaries of the separating films and the press. It is also important to comply with the conditions for pressing PCM, so too low pressure at the time of gelation of the binder leads to a large amount of residual porosity in the material. Too fast heating of the sample leads to a similar result.

Claims (14)

1. A method for preparing a prepreg with a phthalonitrile matrix for obtaining a polymer composite material, including:

formation of a film of low-melting phthalonitrile binder with a thickness of 20-400 microns between two polymer films with an anti-adhesive coating, in a heat press at a pressure of 2 to 10 bar and a temperature of 80 ° C to 140 ° C for 20-600 seconds;

application of the obtained film of low-melting phthalonitrile binder by a direct method using a roller onto the reinforcing filler at the rate of 35 ± 5 wt.% of the binder per weight of the reinforcing filler. 2. A method according to claim 1, characterized in that low-melting phthalonitrile binders with glass transition temperatures not higher than 50 ° C are used as a binder. 3. The method according to claim 2, characterized in that the phthalonitrile binders used are binders formed from (1) a polymerizable mixture comprising: - one or more bis-phthalonitrile monomers selected from 1,3-bis- (3,4-dicyanophenoxy) benzene, 1,3-bis- (3,4-dicyanophenoxy) -2-fluorobenzene, 1,3-bis- (3,4-dicyanophenoxy) -4-fluorobenzene, 1,3-bis- (3,4-dicyanophenoxy) -2-chlorobenzene, 1,3-bis- (3,4-dicyanophenoxy) -4-chlorobenzene, 1, 3-bis- (3,4-dicyanophenoxy) -2-bromobenzene, 1,3-bis- (3,4-dicyanophenoxy) -4-bromobenzene, 1,3-bis- (3,4-dicyanophenoxy) -2, 4-difluorobenzene, 1,5-bis- (3,4-dicyanophenoxy) -2,4-dichlorobenzene, 1,3-bis- (3,4-dicyanophenoxy) -2-methylbenzene, more preferably 1,3-bis - (3,4-dicyanophenoxy) benzene, 1,3-bis- (3,4-dicyanophenoxy) -2-fluorobenzene, 1,3-bis- (3,4-dicyanophenoxy) -4-fluorobenzene, 1,3- bis- (3,4-dicyanophenoxy) -2,4-difluorobenzene, most preferably 1,3-bis- (3,4-dicyanophenoxy) benzene, in an amount of 20-94 wt% based on the weight of the polymerized mixture, - one or more reactive flame retardant plasticizers selected from the group consisting of bis- (4-cyanophenoxy) -phenyl phosphate, bis- (3- (3,4-dicyanophenoxy) -phenyl phosphate, bis- (3- (3,4- dicyanophenoxy) -1-naphthylphosphate, bis- (4-cyanophenoxy) -phenylphosphonate, bis- (3- (3,4-dicyanophenoxy) phenyl) -phenylphosphonate, bis- (3- (3,4-dicyanophenoxy) phenyl) -isopropylphosphate , bis- (3- (3,4-dicyanophenoxy) phenyl) -butyl phosphate, bis- (3- (3,4-dicyanophenoxy) phenyl) -propargyl phosphate, bis- (4-cyanophenyl) phenyl phosphate, bis- (3-cyanophenoxy ) phenyl phosphate and bis-4- (3,4-dicyanophenoxy) phenyl) phenyl phosphate, more preferably from bis- (4-cyanophenoxy) -phenyl phosphate, bis- (3- (3,4-dicyanophenoxy) -phenyl phosphate, bis- (3 - (3,4-dicyanophenoxy) phenyl) -isopropyl phosphate, bis- (3- (3,4-dicyanophenoxy) phenyl) -butyl phosphate, taken in an amount of 5-80 wt.% Of the total weight of the polymerized mixture, and - one or more active diluents selected from compounds of the group consisting of 4- [3- (dipropargylamino) phenoxy] phthalonitrile, 4- [4- (dipropargylamino) phenoxy] phthalonitrile, 4- (4-cyanophenoxy) -benzene-1, 2-dicarbonitrile, 4- (4-cyanophenoxy) phthalonitrile, 4- (3-cyanophenoxy) phthalonitrile and 4- (4-aminophenoxy) phthalonitrile, particularly preferably one or more compounds, 4- (4-cyanophenoxy) - benzene-1,2-dicarbonitrile, 4- [3- (dipropargylamino) phenoxy] phthalonitrile, 4- [4- (dipropargylamino) phenoxy] phthalonitrile, in an amount from 1 to 50% of the total weight of the polymerized mixture; and (2) a polymerization initiator, taken in an amount from 1 to 20% of the total weight of the polymerized mixture, selected from aromatic diamines or bisphenols having a boiling point under vacuum of 0.1 mm Hg. not less than 180 ° C, while the total content of the mixture to be polymerized and the polymerization initiator is from 60 to 100 wt% of the total mass of the binder, preferably the polymerization initiator is selected from the group consisting of 1,3-bis- (4-aminophenoxy) benzene, 4 , 4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, 3,3 '- [(2,3,5,6-tetrafluorobenz-1,4-diyl) bis (oxy)] dianiline, 4,4' - [( 2,3,5,6-tetrafluorobenz-1,4-diyl) bis (oxy)] dianiline, bis [4- (4-aminophenoxy) phenyl] sulfone or bisphenol A, most preferably from 1,3-bis- (4 -aminophenoxy) benzene, or bis [4- (4-aminophenoxy) phenyl] sulfone. 4. The method according to claim 1, characterized in that a fabric or a tape made of glass or carbon fiber is used as a reinforcing filler. 5. The method according to claim 1, characterized in that any films with a glass transition temperature above 130 ° C can be used as the polymer films with a release coating. 6. The method according to claim 1, characterized in that films made of polyethylene terephthalate, polyamide, polyimide are used as the polymer films with a release coating, on which a release coating is applied to ensure the separation of the binder from the film. 7. A method of obtaining a polymer composite material, characterized in that around the layered layers of prepreg with a phthalonitrile matrix, obtained by the method according to claim 1, collect a vacuum bag, evacuate the air to vacuum values <1 mm Hg. and cured according to the following mode: heating to 120-150 ° C at a rate of 2 ± 0.5 ° C / min and contact pressure, followed by heating to 180 ± 2 ° C at a rate of 2 ± 0.5 ° C / min and pressure 2-8 bar, followed by raising the pressure to 10 ± 0.5 bar and holding at this temperature for 8 ± 0.1 h, then the composite is removed from the mold and post-cured at 330 ± 5 ° С for 8 ± 0.1 h, then cooled to room temperature with a cooling rate of no more than 5 ° C / min. 8. The method according to claim 7, characterized in that the polymer composite material has an interlayer shear strength of 34.1-47.1 MPa, a compressive strength of 463.0-662.9 MPa, an elastic modulus of 27.2-55.3 GPa.

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