PHYSICAL-MECHANICAL AND THERMAL-PHYSICAL PROPERTIES EPOXY COMPOSITES FILLED WITH NANOSILVER

Abstract

As components for the formation of epoxy composite material used epoxy oligomer DER–331 (CAS No. 25085-99-8) manufactured by “Dow Chemical Comp” (Germany). For polymerization of the composition, the hardener triethylenetetramine TETA was used, the content of which was q = 10 pts. wt (indicated per 100 pts. wt. of epoxy oligomer DER–331). Silver nanoparticles were chosen as a filler, the content of which was varied in the range – q = 0.025...0.125 pts. wt. When studying the effect of the filler on the adhesive and physical-mechanical properties of epoxy composite materials, the following results were obtained: adhesive strength at breakaway is σа = 46.97 MPa, elastic modulus at bending – E = 3.2 GPa, destructive stress at bending – σb = 102.4 MPa, impact strength – W = 20.1 kJ/m2. The improvement of the properties of the developed material (relative to the epoxy matrix) is due to the significant activity of nanoparticles, as well as a significant specific surface area. That is, the filler when crosslinked with epoxy oligomer absorbs part of the thermal energy and at the same time provides the effect of plastic deformation. This interaction leads to an increase in the strength of the material when exposed to heterogeneous loads. The influence of the thermal field on epoxy composite materials was also determined. The tests were carried out in the temperature range ΔT = 303...473 K. It has been established that to improve the thermophysical properties, it is advisable to use silver nanoparticles with a content of q = 0.050...0.075 pts. wt. Thus, in the temperature range ΔT = 303...323 K, the minimum values of TCLE α = 1.92 – 2.14 × 10-5 К-1. It is shown that at such a content of nanofiller, the material is characterized by increased values of glass transition temperature Tc = 349...352 K, shrinkage is ΔL = 0.37...0.40 %, heat resistance by Martens T = 360-361 K, respectively.