The impact of production temperature of synthetic wollastonite filled with rice husk on its composition and modifying effect

Abstract

Due to finite reserves of naturally occurring wollastonite, production of its synthetic analog on the base of available and renewable raw materials is of paramount importance. In this aspect, the by-products of cereal-processing industry, in particular, rice husk, command great attention of manufacturers. The properties of synthetic wollastonite manufactured on the base of rice husk ash and limestone are affected by the proportion of these components at the greater extent, as well as the synthesis temperature and time defining its phase composition. In this regard, the authors of the paper have studied the impact of production temperature on the structure of synthetic wollastonite and its modifying effect in epoxy compositions as against naturally occurring mineral. The obtained synthetic wollastonite, regardless the synthesis temperature, primarily contains β-wollastonite and larnite as an admixture. For the cost-effective purposes, the optimum temperature for manufacturing synthetic wollastonite on the base of rice husk ash is 800°C. Both naturally occurring and synthetic wollastonite on the base of rice husk enhance hardness of epoxy coatings, whereas the former one increase it in a greater degree due to a higher presence of β-wollastonite of needle-like particles in its composition.