PVC: the molecular weight, viscosity number {(ml/g), (g/ml)}, resin particle size and distribution, sieve residue, volatile content and impurity particle number of PVC resin were detected.
TiO2: the mechanical impurities, residue, appearance and volatile content of titanium dioxide were detected.
CPE: chlorine content and residual crystallinity, apparent density, tensile strength, volatile matter content, decomposition temperature and so on were detected.
CaCO3: the content of CaCO3, residue, fineness, volatile content and content of hydrochloric acid insoluble substance were detected.
While strictly establishing the raw material inspection, we should establish a strict supplier evaluation procedure and select suppliers of high quality raw materials.