PP/PS共混体系在挤出成型中的迁移行为

THE STUDY OF MIGRATION OF PP/PS BLENDS IN EXTRUSION

用傅立叶变换红外光谱(FT-IR)作为定量表征方法,研究了聚丙烯(PP)与聚苯乙烯(PS)共混物在挤出成型中的迁移行为。结果表明,不相容聚合物共混体系PP与PS熔体在挤出口模中流动时会由于剪切产生迁移,形成了粘度较高组分PP的浓度从中心到表层逐渐减小的梯度结构,并且PP的分布近似服从二次分布。

It is well known that particles in initially well-mixed immiscible blends subjected to gradient simple shear flow can migrate and form particle concentration redistribution due to viscosity difference between the dispersion and the matrix. The migration of PP in the PP/PS polymer blends has been investigated with FT-IR as a quantitative method in extrusion with rectangular die. The result shows formation of the structure where the content of PP, with higher viscosity in the blends, decreases in the direction perpendicular to the flow way due to shear-induced migration when flux flows in the die. Besides the distribution of PP meets to second order function, which gives a reference for the research works about the achievement of product with specific structure or property.