Application of Pvc Wire Insulation by Fluidized Bed Methods

摘要

The purpose of the study, was to supplement the previous investigations in the fluidized wire coating area with specialized compound developments. It was the intention to approach this subject from the raw material end, thus presenting an intimate view of the basic requirements in raw materials, discuss their compounding, and determine the physical and electrical properties of the finished materials. An experimental induction heated wire coating set-up was also parpared to determine the applicability of the developments. To achieve the ultimate in economy, processing ease and product homogeneity, the approach was through the dryblending process, rather than the more conventional and costly freeze-grinding methods for fluidizable powder preparation. In the dryblending process, a low molecular weight polyvinyl chloride resin is intensely blended in a high speed mixer with other compounding ingredients to an elevated temperature short of the resin's fluxing temperature. The nature of the specific resin employed is such that high amounts of plasticizer may be readily absorbed without impairing the free flowing requirements of the fluid bed powders. (Author)