Use of vinyl chloride polymers as bulk density modifiers for polyvinyl chloride powder mixtures

摘要

The bulk density of vinyl chloride polymers can be improved by adding, as modifier, up to 25 % by weight of a vinyl chloride homopolymer or copolymer of defined particle size as bulk density modifier to this base PVC. Particle size of the modifier resin is selected so that a bimodal distribution with respect to the mean particle size of coarse (base PVC) and fine component (modifier PVC) results. The inclusion of the PVC fine particles in the gaps between the PVC coarse particles results in an increase in the bulk density. If the particle sizes differ by a factor of more than 50, the bulk density of the base PVC can also be increased by reducing the friction between the base particles.