成核剂对PVC涂覆制品泡孔形态的影响

选择不同拓扑结构的无机成核剂纳米二氧化硅和有机蒙脱土,研究其对PVC增塑糊涂覆发泡制品泡孔形态、结构的影响。通过扫描电子显微镜(SEM)观察样品泡孔形态,采用图像分析手段计算泡孔直径、发泡倍率及泡孔密度,以探明成核剂对泡孔形态结构的影响规律及机制。结果表明:与大多数聚合物熔融体系物理发泡不同,球型纳米二氧化硅对偶氮二甲酰胺(AC发泡剂)主导下的PVC增塑糊涂覆工艺化学发泡过程影响不明显,而插层、团聚分散于PVC增塑糊发泡体系中的有机蒙脱土会增加涂覆制品的泡孔直径,并降低发泡倍率及泡孔密度。

Influence of Nucleating Agent on Foam Morphology of PVC Coating Products

Choosing two kinds of inorganic nucleating agent nano-silicon dioxide(nano-SiO2)and organic montmorillonite(OMMT)with different topologies structure,their effects on cell morphology and structure of foam products prepared by PVC coating was studied.Cell morphology can be observed by using SEM,and cell diameter,foaming ratio and cell density can be calculated by using image analysis means.The effect of nucleating agent on the mechanisms and rules of the cell morphology were researched.It can be found from the results that differing from physical blowing agent with most polymer melting system,spherical nano-SiO2 had little effect on foam processing under the auspices of azodicarbonamide(AC blowing agent)in PVC coating.However,OMMT,which was intercalated and aggregated in PVC foaming system,increased the cell diameter,and decreased expansion ratio and cell density.