Optimization of the particle size and structure parameters to receive dispersed filled polymer composites with maximum strength characteristics

Abstract

For the first time, the generalized (Θ) and normalized (amid/d, Θ/B, and Θ/Sf) parameters were used to describe the dispersed structures and strength properties of DFPCM for different contents of a dispersed filler with different specific surface area (Sss) and particle diameter (d). This made it possible to determine the optimal parameters of the filler, its content and the type of dispersed structure with maximum strength. The optimal parameters of investigated system (FA + SiО2) were: amid/d ≈ 0.25–0.3; Θ ≈ 0.5–0.55 b.v.; Θ/В ≈ 2.0–2.5 и Θ/Sf ≈ 0.8–1.0. They are achieved by using silica-fi ller with specific surface area Sss = 1 m2/g and particle diameter d ~ 2.25 μm, the volume content of filler was ~20–25 volume % (0.2–0.25 b.v.). The optimal structure for disperse-filled polymer composite material is middle-filled system (before yield strength). It was determined, that the optimal particle size depends on interaction between growing crack and dispersed inclusions while composite is destructed as well the length of the phase boundary (normalized parameter Θ/Sf). To sum up, it is necessary to use only generalized and normalized parameters (аmid/d, Θ, Θ/В and Θ/Sf) to determine the optimal of dispersed fillers and the structure of DFPCM with maximum strength.