RU2629078C1 - Inert filler composition - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: inert filler composition contains filler components and a binder consisting of an epoxy resin and amine curing agent. As the filler components, a mixture of rubber crumb with a shot made of chipped ferrous metals is used.

EFFECT: invention provides an inert filler composition that is versatile with a wide range of density control and appropriate mass and adhesion properties.

1 tbl, 2 ex

Description

The invention relates to rocket science, and in particular to the development of simulators of fillers of combustion chambers of fuel (NKST).

Known compositions for producing inert fillers, in which calcium oxide and salt materials, rock materials, metal carbonates, aluminum are used as filler components, and polyolefins, paraffins, polyvinyl chloride, synthetic rubbers are used as a polymer base (US Patent Nos. 3,936,403, No. 4119606, USSR No. 1779684, etc.).

The purpose of these compositions is to simulate the properties of NKST, having a strong bond with the power case.

A known composition for producing an inert filler, adopted as a prototype (RF patent No. 2475466), which contains the following mass ratio of components:

dispersed spherical aluminum (filler) 5.00-17.00 divinyl rubber with terminal carboxyl groups 15.64-16.70 (binder) epoxy resin (binder) 3.80-5.60 transformer oil 2.20-2.80 tetramethylthiuram disulfide (thiuram D) 0.10-0.20 (vulcanizing reagent (hardener)) zinc oxide 0.10-0.40 lecithin or cationate-7 0.19-0.21 potassium chloride (filler) rest

It should be noted that the above composition does not allow you to adjust the final density of the inert filler in a wide enough range, which is a significant drawback, because imitation of various types of NCCT with a density in a wider range is required. One of the reasons for this is the low density of the filler (spherical aluminum and potassium chloride).

The density presented in the patent prototype inert filler is in the range from 1.609 to 1.607 g / cm ³ . This range is obtained by the formula:

,

,

where i is a component of the composition of the prototype (from 1 to 8),

m% _i - mass part of the i-th component, wt. %

ρ _i is the density of the i-th component, g / cm ³ .

The expansion of the density range without a significant change in the mass parts of the components is not possible. Moreover, going beyond the ranges of mass parts indicated in the prototype patent leads to unacceptable changes in the physicomechanical properties of the inert filler.

In addition, the composition of the prototype has other disadvantages:

• not technologically advanced to manufacture due to the large number of components;

• contains a large amount of transformer oil, which is able to diffuse at the interface, thereby violating the thermodynamic stability of the prescription composition system.

Transformer oil diffusing to the “filler-casing” interface impairs adhesion of the inert filler to the walls of the power casing.

The objective of the invention is to create a universal composition of an inert filler with a wide range of density control to obtain mass production models with the corresponding mass-centering and adhesive properties.

The technical result consists in the possibility of modeling the density of all existing fillers of the combustion chambers by filling the air pores with a split shot formed by the compound of rubber crumb particles of various shapes and sizes.

The technical result is achieved by the fact that the composition of the inert filler contains filler components and a binder consisting of epoxy resin and amine hardener, a mixture of rubber crumb and crushed chipped from ferrous metals is used as filler components, in the following ratio of components, mass parts:

The use of fractions chipped on the basis of ferrous metals (DChK 03, DChK 05, DSK 03, DSK 05) in an amount of 48.7 to 57.2 mass parts allows with high accuracy and in a fairly wide range to control the density of the inert filler. In addition, the used chipped fraction can be a waste of other industries, which ultimately significantly reduces the cost of inert filler. The use of crushed fractions ensures a strong bond of the particles of the fraction to the rubber crumb due to the presence of planes on the grains of the fraction, along which a strong adhesive boundary is formed through the binder.

The need to use fractions of precisely ferrous metals is due to the density of ferrous metals in the range from 7.80 to 7.85 g / cm ³ .

The use of metals with a lower density narrows the range of regulation of the density of the inert filler. The use of metals with a higher density leads to their subsidence at the bottom of the mixing device and, as a consequence, to the uneven density of the inert filler.

In the course of the experimental work, technological limitations of the range of the density simulated by an inert filler were identified, associated with the uneven distribution of the crushed ferrous metal fraction with its content of less than 48.7 mass parts and a significant increase in the viscosity of the prepared inert filler with the crushed fraction of more than 57.2 mass parts, which equivalent to the density range of the inert filler from 1.5 to 1.8 g / cm ³ .

Rubber crumb provides a fixed volume of inert filler (rubbers based on butadiene, styrene butadiene and butyl rubber, grades: SKD, SKD-2, BK-1675N, BK-1570, SKDLR-1,2, etc. - material as a waste product) which in the recipe is from 25.6 to 30.7%. Rubber crumb provides greater porosity of the inert filler due to the connection through a binder of particles of rubber crumb of various shapes and sizes. The resulting air pores (from 53 to 55% of the volume) are uniformly filled with a shot of ferrous metals to the desired density of the inert filler.

The volume fraction of rubber crumb within the simulated density range is 46%, taking into account an error of ± 1% due to the inconsistency of the geometry of the crumb particles. When recalculating the constant volume fraction of rubber crumb into mass fractions according to the formula:

m% _crumbs = 46.0 / ρ _simulated ,

where m% _{rub. crumbs} - mass fraction of rubber crumb, wt. %

ρ _simulated - the density of the simulated NCCT, g / cm ³ , and when taking into account the density range of the inert filler from 1.5 to 1.8 g / cm ³ due to the content of the crushed ferrous metal fraction, the range of mass parts of crumb rubber in the inert filler will be from 25.6 to 30.7%. An increase in the mass fraction of rubber crumbs by more than 30.7% leads to an increase in the volume occupied by the mixture and, as a result, uneven distribution of the mass of the inert filler and incomplete wetting of the rubber crumb with a binder. The decrease in the content of rubber crumb less than 25.6 mass parts leads to a decrease in the volume occupied by the mixture, which leads to uneven distribution of mass of the inert filler.

An epoxy resin (K-153, ED-20, E-40) is used as a binder in combination with an amine hardener (polyethylene polyamine, triethanolamine titanate, hexamethylene diamine). Epoxy binder allows you to firmly fasten the components of the inert filler. The high rigidity of the epoxy binder is compensated by the large volume content of rubber crumb, which gives elastic properties to the inert filler.

The volumetric content of the binder when the density is simulated in the range from 1.5 to 1.8 g / cm ³ is constant, determined experimentally, ranges from 30 to 32 volume parts and provides complete wetting of the rubber crumb. When converted from bulk parts to mass parts according to the formula:

m% _binder = V% _binder / ρ _simulated ,

where m% of the _binder is the mass part of the binder, wt. %

V% _binder - volumetric part of the binder, vol. %

ρ _simulated - the density of the simulated NCCT, g / cm ³ .

Based on this, m% of the _binder is in the range from 17.1 to 21.5. The compounding ratio of resin and hardener: 100 mass parts of resin to 15 mass parts of hardener, the ratio provides complete polymerisation of the resin. Based on this, a range of mass parts of resin from 14.9 to 17.9 and hardener from 2.2 to 2.6 was obtained.

The advantages of the obtained inert filler are:

• wide range of adjustable density;

• manufacturability (due to the small number of components);

• simplicity of density regulation during the preparation of the composition;

• satisfactory adhesion of the inert filler to the walls of the filled housing (lack of delamination from the walls of the housing).

The table shows examples of formulations inert fillers simulating different densities.

An example of the composition and preparation technology of an inert filler to fill a volume of 100 dm ³ with an inert filler with a density of 1.54 g / cm ³ (1.54 kg / dm ³ ):

1. Weigh the components of the composition in the required mass ratio for the volume to be filled:

Epoxy Resin (K-153) 26.95 kg Polyethylene polyamine 4.00 kg Chipped fraction based on ferrous metals (DChK 03) 77.00 kg Rubber crumb (mixture of SKD, SKD-2, BK-1675N, etc.) 46.05 kg

2. To mix the components of the composition in the following sequence:

- mix the rubber crumb until lumps are removed;

- Continuing mixing, pour in the resin, mix until the chips are completely wetted;

- Continuing mixing, pour polyethylene polyamine, ensuring uniform distribution;

- Continuing mixing, pour a shot with a stream, mix until even.

3. Unload the composition into the body of the layout during the viability of the composition.

4. To polymerize within 24 hours at a temperature of 15 to 35 ° C.

The range of densities between 1.5 and 1.8 g / cm ³ tested on the model and the buildings by the above technologies, confirmation these advantages, the composition having a density of 1.54 g / cm ³ of the housing 2 filled with a volume of 100 dm ^3. In cases filled with an inert filler, the required landing dimensions, mass, center of mass coordinates and satisfactory adhesion (bonding) of the inert filler with the power shell, verified by non-destructive testing, are provided.

Thus, the described composition of the inert filler is universal, with a wide range of density control and the corresponding mass-centering and adhesive properties.

Claims (2)

The composition of the inert filler contains filler components and a binder consisting of an epoxy resin and an amine hardener, characterized in that the mixture of rubber crumb and crushed chipped from ferrous metals is used as filler components in the following ratio of components, wt. hours: Epoxy resin 14.9-17.9 Amine hardener 2.2-2.6 Black shot chipped 48.7-57.2 of metals Rubber crumb 26.3-29.9