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Experimental data and generalized dependences of the effect of molecular characteristics of epoxy diane oligomers (EDOs) and mixtures thereof of various compositions on the value of volume shrinkage are presented. It is established that EDOs and mixtures thereof with a low molecular weight (to 400) and the content of the first fraction over 90 vol % have the highest value of shrinkage by the moment of gel formation, which allows one to obtain polymeric composite materials and adhesive joints with a low level of residual stresses and high physicomechanical characteristics.

A method for calculation of molecular characteristics and compositions of the mixtures of industrial epoxy diane oligomers (EDOs) with the given parameters of molecular weights and molecular weight distribution is proposed. Using the rheokinetic investigation techniques, the time ranges of the initial stages of EDO curing were defined and the dependence of time parameters of curing on the molecular characteristics and fractional compositions of the mixtures of these oligomers were determined. The investigations performed allow calculation, prediction, and optimization of compositions of epoxy binders and technological parameters of different stages of the production of polymer-composite materials and adhesive bonds with a complex of given properties.

This article demonstrates the potential for both homogeneous and heterogeneous structures to form in oligomer blends. The nature of the dependence of viscosity on the composition of the heterophase blend has been found to be governed by the phenomenon of wetting of the surface of the disperse phase dispersion medium. Selectivity offiller distribution in oligomer blends is shown. Also demonstrates the potential for filler formation during the actual composite matrix curing process.

An investigation was made of the influence of the molecular characteristics of industrial bisphenol-A epoxy oligomers of grades DER-330, ED-20, ED-16, and ED-8, and the molecular characteristics of their blends, on their rheological properties. It was shown that the viscosity of the oligomers and their blends is connected with the content of low-molecular-weight fraction. A procedure is proposed that makes it possible, by changing the fractional composition, to produce a blend of epoxy oligomers with a given viscosity.

This paper presents a review of the literature on polymer nanocomposites and their properties and structure. Different types of nanofiller and the properties of composites based on them are examined. Also, the principal problems associated with the creation of materials of this kind are set out – uniform distribution of the nanofiller in the polymer matrix and the guarantee of effective load transfer from matrix to filler. The current main methods for uniform dispersion of nanofillers in the polymer matrix are described: selection of the optimum mixing conditions, in situ polymerisation, and chemical modification of nanofiller particles.

The specifics of the phase structure, rheological properties, and mechanical characteristics of cured and liquid blends of reactive oligomers are discussed, as well as filled compositions in the form of emulsions on their basis. One of the main factors that determine the properties of these blends is their phase composition and the colloid-chemical structure. In the filled emulsions, an uneven distribution of filler between the phases is possible. If the emulsion structure of the two-phase blends of reactive oligomers is fixed during their curing, the blends may exhibit quite surprising properties.

Crosslinked materials with different phase structures can be produced in hardening of the binary mixtures of unsaturated polyester resins or mixtures of epoxy resins. The dependences of the mechanical and electrophysical properties on the formula of such mixtures have been determined. The properties of filled compositions based on these mixtures with a two-phase structure, which have been produced by selective introduction of the filler only into one phase of the composition, significantly differ from the properties of filled single-phase mixtures and from the properties of two-phase mixtures produced with a uniform distribution of the filler in both phases.

The rheological properties of ED‐20‐epoxy‐resin‐based compositions filled (10–50 vol.%) with quartz sand, quartz flour, or their mixture have been investigated on Reotest‐2 and RV‐8 rotational viscosimeters. The relative viscosity of the filled compositions increased with their free volume according to the exponential equation with an exponent of 2.6. The compositions began to show an anomaly of viscosity in flowing for a content of the filler of more than 40 vol.%; the yield stress appeared for 50 vol.%. The rate of spreading of the compositions on a horizontal surface decreased with increase in the composition viscosity according to the exponential equation with an exponent of 1/8, which is similar to that calculated theoretically. The experiments conducted allowed calculation of the formula of epoxy‐based, self‐leveling pouring floors.

By comparing numerous rheological and theoretical equations describing the dependence of the viscosity of dispersions on the concentration with the dependence of the viscosity of liquids on their free volume, the authors concluded that the dependence of viscosity on the concentration can be described in terms of the so-called “free volume of disperse systems”, i.e. the difference between the maximum possible content of particles in the system ϕmax and the actual concentration ϕ: (ϕf=ϕmax−ϕ). This comparison is based on the uniformity of models based on theoretical descriptions of the flow of concentrated dispersions and liquids at molecular level, including the transition region to dispersions losing their fluidity at ϕ → ϕmax on the one hand, and the glass transition region of liquids, on the other hand. The behaviour of both types of systems in the region close to the limiting region is described by the cluster theories and the percolation theory. Experimental data on the concentration dependence of the viscosity of dispersions are given and it is shown that within a certain concentration range they can be described by equations containing parameter ϕf which are similar to Batschinski's or Doolittle's equations. The approach developed by us has been extended to describe other mechanical properties of highly-concentrated dispersions. Further analogy is drawn between the mobility of particles in concentrated dispersions and the glass transition region. Experimental comparison of the data on the compaction rate of highly-concentrated composites under vibration with the free volume of these composites suggested that transition from the high mobility of particles to the “frozen” state occurs at a constant free volume value of dispersions, 15–17 vol.%. We discuss the advantages of the analog method used for systems similar in structure (or in the method of describing structural changes) in spite of considerable differences in the scale of the phenomena being described.

1. Investigations were conducted to determine the critical value of the ratio of the dimensions of the core and the cross sectional area of the specimens of the highly filled composite of the polymer beton type α = 0.1. When this critical value is reached, the ultimate strength and elasticity modulus decrease. At α ⩽ 0.1, these parameters remain unchanged. 2. It has been established that the Young's moduli in tensile and compressive loading of the polymer binder based on the FA monomer are equal irrespective of the hardening conditions. 3. The results show that the preliminary loading of the polymer binder of the highfilled composite of the polymer beton type reduces the elasticity modulus of the binder.

1. Application of the free volume criterion to highly filled composite materials permits obtaining the quantitative characteristic which determines the behavior of composites with mechanical effects. 2. Optimization of the composition of a multifractional mineral filler and consideration of the interaction of the liquid binder with its surface permit regulating flow of highly filled composites and their capacity for processing.