Composite material

FIELD: chemistry.

SUBSTANCE: invention relates to composite materials which can be used in aircraft construction. The composite material is made from aramid type fibre reinforcement (bundle) and a composition consisting of a mixture of epoxy resins as a polymer matrix and an aromatic amine as a hardening agent, with the following ratio of components in wt %: epoxy resin UP-610 17.6-24.7, aliphatic epoxy resin DEG-1 3.1-4.4, aromatic amine UP-0638 4.2-6.0, aramid type fibre reinforcement 65-75.

EFFECT: composite material has better elastic and strength properties, particularly Young's modulus of elasticity of 123 GPa and ultimate tensile stress of 2,57 GPa.

1 cl, 2 tbl, 3 ex

 

The invention relates to composite materials based on epoxy resin and a fibrous filler (harness) aramid type that can be used in the construction of aircraft.

Known composite material brand OP-MS/17-N (Passport reg. No. 0553-35 from 04.09.97)containing as filler harness "Armos" aramid type and binder up-2217. The composition of the binder up-2217, wt.%:

resin pack-610 (TU 2225-546-00203521-9840
or THE 2225-606-11131395-2003)
resin deg-1 (TU 2225-027-00203306-97to 6.67
or THE 2220-527-00203521-98)
resin ED-22 (GOST 10587)20
hardener Diameter-X (TU 6-14-980-84)33,33

For more information about the components presented in table 1.

The disadvantages of this material include the level uprugoopticheskii properties of a composite material, the complexity of the composition of the binder and environmental hazard due to the high content of the curing agent is probably carcinogenic substance.

Technical C is the summer residence of the invention is to improve uprugoopticheskii properties of composite material. The technical result is achieved by using a new epoxy binder composition, wt.%:

resin pack-61070,5
resin deg-112,5
a mixture of aromatic amines 4,4'-diaminodiphenylmethane and
metaphenylenediamine (yn-0638)17

Table 1
№ p/pComponentChemical basisRegulatory documentationHazard class
1Resin pack-610The condensation products of p-aminophenol and of epichlorohydrin, followed by dehydrochlorination alkaliTHE 2225-546-00203521-98, THE 2225-606-1113195-2003para-aminophenol, 2-epichlorohydrin-2
2Resin deg-1The condensation product of epichlorohydrin with polyhydric alcohols, followed dihydrochloride the receiving lye THE 2225-027-00203306-97, THE 2220-527-00203521-98the epichlorohydrin-2
3Resin ED-22Epoxy resin (polymer diglycidylether ether)GOST 10587the epichlorohydrin-2 toluene-3
4Hardener Diameter-XDichlorodiphenylmethaneTHE 6-14-980-843 probably carcinogenic product

The binder content, wt.%: 25-35; the content of the fibrous filler aramid type, wt.%: 65-75.

The technical result is achieved by a combination of mechanical and adhesive properties of the new polymer matrix of the above composition, which leads to an increase of the resulting physical and mechanical properties of the composite.

It is known that the characteristic of the molecular structure of the epoxy polymer matrix is the structure of elementary site chemical covalent grid, which is determined by the nature of the source diepoxide. In the most well-known epoxy-amine polymer is trifunctionally site, which consists of two molecules of epoxy resin and one - amine the CTE is the founder with the center node the nitrogen atom

During curing amines, new hydroxyl group and a tertiary nitrogen atom in the centre of the grid.

Aliphatic resin (deg-1, TAG-1 and others) contain a large amount of epoxy (15-30%) groups and have a low viscosity (at 25°C 0.05 To 1 PA), which allows to use them in prescription formulations as the active diluents other epoxy resins which helps to increase the elasticity and impact strength of solidified polymer matrix.

The choice of aromatic amine as the curing agent due to the heat resistance of the resulting polymer (160-200°C). To improve its compatibility with epoxy resins, it is advisable to use low molecular weight epoxy resin (Mcf=350-600) in combination with low viscosity aliphatic. Thus the variation of the molecular structure of epoxy oligomers and their combination among themselves and hardeners can be directed to control the properties of polymer matrix and composites based on them.

Composite material made by the method of "wet winding". In the reactor by sequential mixing of the components is formed of epoxy binder, which is transported into the tub. Through the bath extends harness (roving or cloth)supplied to the mandrel for winding the product.

For measuring the population of physico-mechanical properties of samples of a composite material produced by winding the impregnated tow "Armos" on a special holder. The mandrel was placed in a heat chamber, where were the mode of curing the binder is graded according to the technological scheme:

rise to 85°C free;

aging at 85°C - 6 hours;

rise up to 100°C free;

exposure at 100°C - 2 hours;

rise up to 140°C - free;

aging at 140°C - 2 hours;

rise to 160°C - free;

aging at 160°C - 6 hours;

the cooling thermostat.

After cooling mandrel made eat samples of composite material for subsequent determination of physical-mechanical characteristics - destructive tensile stress and elastic modulus of a composite material according to OST 92-1473-78.

Experimental results the proposed composite material are shown in table 2. For example, for a composition with the following ratio of components, wt.%

resin pack-61020,4
resin deg-13,6
a mixture of aromaticamines
4,4'-diaminodiphenylmethane and
metaphenylenediamine (yn-0638)6
fibrous order the tel aramid type 70

corresponding values destructive tensile stress at 20°C Is To 2.57 GPA, modulus of elasticity - 123 GPA.

For the received material value destructive tensile stress at 20°C 4.9% higher compared with the equivalent value of the modulus of elasticity is higher by 23%.

Thus, when using a binder of the above new formulation obtained a new composite material that has a higher physical and mechanical characteristics.

Table 2
IndexBase case composite material: harness "Armos" + binder up-2217The proposed composite material
Harness "Armos" (75 wt.%) + new epoxy binderHarness "Armos" (70 wt.%) + new epoxy binderHarness "Armos" (65 wt.%) + new epoxy binder
Ultimate tensile stress tensile 20°C, HPa2,452,56to 2.572,54
The module is provosty, HPa100120123121

Composite material made by the method of wet winding of the fibrous filler (harness) aramid type and composition, consisting of a mixture of epoxy resin as a polymer matrix and an aromatic amine as a curing agent in the following ratio, wt.%:

epoxy resin NC-61017,6-24,7
epoxy resin aliphatic deg-13,1-4,4
aromatic amine UE-06384,2-6,0
fibrous filler aramid type65-75



 

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6 cl, 2 tbl, 10 ex

FIELD: technological processes.

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1 tbl, 6 ex

FIELD: technological processes.

SUBSTANCE: method includes the following: viscose or polyacrylonitrile technical thread is soaked with the mixture of epoxy resin ED-20 and hardener polyethylene polyamine with mass ratio 9:1. Then bundle is formed out of separately soaked technical threads with the number of threads of 100-140 and is thermally treated at the temperature of 30-70°C. At the same time the shaped bundle is exposed to ultraviolet radiation with power of 0.70-0.80 Watt/m3 at the wave length of λ=253.7 for 8-12 minutes, and then hardened.

EFFECT: increases breaking stress during static bending of materials with polyacrylonitrile technical thread.

2 tbl

FIELD: chemistry.

SUBSTANCE: invention relates to selectively removable intermediate coating compositions, containing at least one polyamide with a terminal amino group, in which average molecular weight of the polyamide with the terminal amino group ranges from 500 Da to 100000 Da. The invention also relates to a multilayer coat containing a first coat (basic coat); a second coat (outer coat); an intermediate coat between the first and second coats, in which the intermediate coat contains at least one polyamide with a terminal amino group, which is used to coat surfaces of aircraft and spacecraft.

EFFECT: obtaining a coating composition for facilitating selective removal of the outer and intermediate coats by washing off without removing the basic coat.

46 cl, 4 ex, 1 tbl

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