The present paper deals with evaluating bactericidal properties of polyvinylchloride compositions for linoleum manufacturing. PVC-floor coatings are widely used in health care facilities, hospitals and outpatient departments due to antistatic properties, non-toxicity, advanced resistance to wear, fastness to water, functionality and improved durability. Strict standards of resistance to bacteria and fungi are applied to this type of coatings due to their exposure to detergents and washing agents. Modifying PVCcomposition by calcium methylsilicate, also known as wollastonite, increases its resistance to Gram-positive and Gram-negative organisms. Cationic surface-active substances are active to both type of microorganisms and could withstand propagation of bacterial medium on polyvinylchloride linoleum surface. They also exhibit the functions of biostatics inhibiting the growth of microorganisms and of bactericides killing microorganisms. Quaternary ammonium compounds represent efficient group of biocides for water-dispersible coating materials and for this reason their investigation for PVC-linoleum is of utmost interest. PVC floor coatings modified by wollastonite are more resistant to aggressive chemical liquids and microorganisms than linoleum with the base composition. The authors proved that PVC-based linoleum with surface-activated filler, wollastonite, had shown enhanced fastness to water and higher resistance to water solutions of antiseptic agents and bacteria.

As a modifying additive in PVC-compositions, silicates produced by means of rice husk processing are of practical interest. Rice husk ash obtained by burning at 350°C, along with synthetic and naturally occurring wollastonite, significantly reduce plasticizer’s migration from the PVC-composition due to their porosity. This is due to the fact that the part of hydroxyl components of the plasticizer EDOS has adsorbed on the surface or retained by the silicates pores. Along with that, Miwoll 10-97 ensures a greater decrease in plasticizer’s migration than synthetic calcium silicate on the base of rice husk ash. When all the researched silicates are modified by the rice husk and naturally occurring wollastonite, heat stability of PVC-compositions grows. This is preconditioned by the alkaline origin of the surface of filling compounds that allows their possible reaction with chlorine hydride released from PVC during thermal decomposition. Synthetic and naturally occurring wollastonite enhance strain-strength properties of PVC-compositions whereas silicates on the case of rice husk reduce these parameters.

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Due to the growing use of polymer materials, in particular in construction sphere, the issue of their recycling at the end of their service life is particularly relevant. Being the base for flooring, plasticized PVC-compositions, are utilized by soil microbial flora, as the plasticizer EDOS has a positive effect on the microbiocenosis of the soil. It was shown that for aqueous extracts of samples of PVC-compositions, there is no toxicity for two test objects - infusoria Paramecium caudatum and crustacean Daphnia magna. Filling plasticized PVC-materials with natural wollastonite Miwoll 10-97 inhibits the processes of soil respiration, and rice husk ash and synthetic wollastonite on its base, contribute to its preservation. At the same time, the use of these fillers reduces the degree of utilization of plasticized PVC-compositions by soil microbial flora, since the plasticizer EDOS is adsorbed on their surface and becomes less accessible for soil microorganisms. This was proved by infrared spectroscopy and occurs due to the formation of hydrogen bonds between EDOS and rice husk ash.

This article examines the use of waste rice processing as a promising fillers for PVC finishing materials. Due to the presence of amorphous silicon dioxide these fillers improve the performance properties of filled PVC, while lignin and cellulose in their composition accelerate biodegradation when buried in the soil. The use of these wastes allows solving the problems of “green” chemistry and closed-cycle economy and reducing the cost of finished polymer products. The paper studies the effect of ash of rice husk and synthetic wollastonite on its basis on the diffusion processes occurring during mixing of PVC and plasticizer. Activation of the RHA surface by CATAPAV significantly affects its elemental and particle size distribution and structure porosity, leading to a decrease in the porosity of the filler, reducing its particle size and narrowing the distribution of particles and pores in size. At use of silicate fillers of optimum composition growth of tensile strength, thermal stability and decrease of plasticizer migration from PVC compositions, owing to plasticizer retention in pores of these fillers is reached.