Volume 7 # 1 Композиты и Наноструктуры

2015_COMPOSITES and NANOSTRUCTURES

CONTENS

Zarubin V.S., Kuvyrkin G.N., Savelyeva I.Y.

THERMAL CONDUCTIVITY OF THE TEXTURED COMPOSITE WITH ANISOTROPIC

LAMELLAR INCLUSIONS ..........................................................................................................................................................................1

A mathematical model of thermal energy transfer in a composite with anisotropic inclusions in the form of three-axis ellipsoids the procedure

of calculation of tensor components of effective thermal conductivity of the textured composite containing lamellar inclusions modelled by

strongly flattened spheroids of a transversal isotropy around a relative axis of rotation is suggested. The general model was developed earlier.

Calculations for various of conic textures of the composite are carried out. Results obtained can be used for an evaluator of effective

coefficients of thermal conductivity of the textured composites modified by nanostructural elements (in particular, by graphene fragments).

Due to electrothermal analogy, these results are applicable to consideration of characteristics of electric conductivity and dielectric permeability

of textured composites (p. 1-13; fig. 3).

Belov P. A.

GENERAL DECISION IN THE SPECIFIED MINDLIN'S THEORY......................................................................................................14

The general decision of the specified Mindlin's theory equations is under construction. Specification is that a tensor of moduli of the sixth rank

contains not eleven moduli as in the classical theory of Mindlin but only seven. Earlier it was proved that such reduction of nonclassical moduli is

defined by implementation of the requirement of positive definiteness of potential energy. The constructed decision for displacements is presented

in the form of superposition of three vector fields: field of classical displacements and two fields of cohesive displacements which can be treated as

nonclassical amendments in Mindlin's theory to the classical decision for displacements. Fields of cohesive displacements satisfy to the generalized

biharmonic equations which can be presented as multiplication of two different Helmholtz' operators. Unlike Toupin's theory in which there is one

field of cohesive displacements, in the specified Mindlin's theory the number of such cohesive fields is two, and they can be complex interfaced. It

leads to possibility of the description qualitatively of other fields of displacements, than in the classical theory of elasticity or the gradient theory

of Toupin. Besides, the decision for a field of free distortion which along with the fundamental functions entering expressions for displacements

contains three additional fundamental decisions is constructed. These fundamental decisions can't be presented in the vector form as they have the

different tensor nature and ranks. One decision is a pseudo-scalar and defines potential part of a vector field of spin. Two other fundamental decisions

are defined by independent components of a tensor-deviator of free distortions on which the additional requirement of equality to zero its

divergention is imposed (p. 14-24).

Vasiliev V.V., Lurie S.A.

MODEL OF A SOLID WITH MICROSTRUCTURE...............................................................................................................................25

The paper is concerned with mathematical simulation of the solid for which the classical equations of solids based on the analysis of the field

functions behavior in the vicinity of a point are not valid. The solid is assumed to consist of a system of particles whose small but finite

dimensions does not allow us to single out an infinitesimal volume element and to apply directly the classical differential calculus. It is

proposed to use the obtained expressions for scalar, vector and tensor functions to study the problems whose solutions obtained within the

framework of the classical solid mechanics are characterized with high gradients or are singular. A beam under uniaxial tension and a model

singular spherically symmetric problem are considered as examples (p. 25-33; fig. 1).

S.M. Nikulin, A.A.Tashkinov, V.E.Shavshukov, A.V. Rozhkov, V.V.Chesnokov, E.A.Paukshtis

A DEVELOPMENT OF THE METHOD OF INTRODUCING

MULTI-WALLED CARBON NANOTUBES IN EPOXY POLYMERS

TO ENHANCE STRENGTH OF THE MATERIAL .................................................................................................................................34

Two variants of the modification of epoxy resin obtained from resin ED-20 by functionalized carbon nanotubes with a predominance of the

carboxyl and hydroxyl functional groups. The strength ofthe modified polymer samples obtained by methods of «cold» and «hot» polymerization

was measured. Concentration range ofmultilayer carbon nanotubes with predominant content of carboxyl groups the epoxy resin corresponding

to the largest increase in the compressive strength is found. (p. 34—10; fig. 1).

D.L.Starokadomsky, E.M.Pahlov

PHYSICAL AND MECHANICAL PROPERTIES OF EPOXYPOLYMER COMPOSITES

FILLED WITH 10 - 50 WT% OF PYROPHILLITE..................................................................................................................................41

The prospects of epoxy-polymer with low-cost filling is shown. It is also shown that filling of polyepoxide with micro- and nanoparticles of

pyrophillite leads to an increase in heat resistance and chemical resistance of the composite, and lower its shrinkage. Abrasion resistance increases

with an increase in the composite filling. On the other hand, the filling does not increase the strength of the majority of measured characteristics.

Compressive strength decreases with increasing content of pyrophyllite, and after 10 wt% the fracture behavior changes from plastic to brittle.

There was no increase in tensile strength of GFRP. The composite adhesion to GFRP increases only at certain filling (10 wt%).

Derivatography method shows that filling does not change a temperature of 10% weight loss. The mass of burnt material is proportional to

filling content. Oneside heating method does show that pyrophyllite enhances thermal stability of the polyepoxide, especially at high filling

in the primary and secondary stages of decomposition. Also with increasing filling content increases resistance to swelling in ether-acetate

ink-solvent. Thus, pyrophyllite may be used as a low-cost filler for polyepoxide to improve some practically important properties (abrasion

resistance, heat resistance, resistance in a solvent) (p. 41-51; fig. 9).

A.I.Samatadze, V.A.Nikiforov, LV.Parahin

A STUDY OF PROPERTIES OF ORANOSILICON BINDERS WITH ADDITIVES AS A BASE FOR

THE DEVELOPMENT OF GFRPS FOR RADIO-ENGINEERING APPLICATIONS...........................................................................52

A possibility of creating a glass fiber reinforced plastics with low toxic and low viscosity organosilicon binders. The influence of

oligomer type, monomers, catalytic systems and stabilizing additives on viscosity, live time, quality, termostability, ash curing

compositions is shown. An optimal of oligomer-monomer composition is suggested (p. 52-58).

ISSP RAS