Effects of paste resins on the foaming properties of PVC plastisols

This article studies the foaming properties of PVC plastisols prepared from six different types of PVC paste resins with different degrees of polymerization that were produced through two methods, a seed emulsion method and a micro‐suspension method. The underlying mechanisms that result in differences in the foaming properties are discussed as well. The results indicate that formulation S5 has the best foaming quality using past resins produced with the seed emulsion method, and formulation S6 made the best plastisol samples from paste resins produced through the micro‐suspension method. Seed emulsion‐produced paste resins with low degrees of polymerization are more suitable for preparing high‐quality foam materials. The parameters used to judge the foam quality are the initial decomposition temperature Tf (5%), Tf − Tηmax and Tf (5%) − Tηmax. The greater the value of these three parameters, the better the foaming effect. The degree of polymerization of the paste resin and the particle morphology directly affect the rheological parameters, namely Tηmax, of PVC plastisol, and subsequently affect the magnitude of Tf − Tηmax and Tf (5%) − Tηmax, which in turn affect the quality of the foam. The parameters used to judge the foam quality are the initial decomposition temperature Tf (5%), Tf − Tηmax and Tf (5%) − Tηmax. The greater the value of these three parameters, the better the foaming effect. The degree of polymerization of the paste resin and the particle morphology directly affect the rheological parameters, namely Tηmax, of PVC plastisol, and subsequently affect the magnitude of Tf − Tηmax and Tf (5%) − Tηmax, which in turn affect the quality of the foam.