Influence of rice husk ash and wollastonite on plasticizer migration in polyvinyl chloride system

Abstract

The influence of rice hull ash and wollastonite on the migration problem of plasticizer EDOS from polyvinyl chloride (PVC) has been studied. The methods of optical interferometry, IR spectroscopy, viscometry, SEM and EDX were used to study the mutual solubility and diffusion mobility in the PVC‐EDOS system in the presence fillers and without them, as well as the phase structure of plasticized filled systems. It is shown that in a fully compatible PVC‐EDOS system, a diffusion mixing mechanism is observed, and the interdiffusion coefficients increase from 10−8 to 10−6 (cm2/s) with increasing plasticizer concentration. The introduction of a dispersed filler somewhat reduces the interdiffusion coefficients. The sorption of the plasticizer on the surface of the dispersed filler has been established, which leads to a decrease in the migration of EDOS from the composition. It was found that the introduction of wollastonite leads to a smaller increase in viscosity and an improvement in the technological properties of the system. And the introduction of environmentally neutral rice husk ash reduces the migration of the plasticizer and improves the stability of the composition during operation, which also has a positive effect on the environmental friendliness of this system.