文献类型：会议论文

英文题名：Nucleating efficiency of organic phosphates in polypropylene

作者：Zhang, GP; Xin, Z; Yu, JY; Gui, QD; Wang, SY

机构：[1]E China Univ Sci & Technol, Polymer Proc Lab, Shanghai 200237, Peoples R China;[2]Donghua Univ, Coll Text, Shanghai, Peoples R China

会议论文集：International Symposium on Polymer Crystallization

会议日期：JUN 09-12, 2002

会议地点：MISHIMA, JAPAN

语种：英文

外文关键词：nucleating efficiency; organic phosphate; polypropylene; crystallization behavior; thermal stability; mechanical property

摘要：Organic phosphates used as nucleating agents can remarkably promote the stiffness and crystallization rate of polypropylene homopolymer and ethylene-propylene copolymer. In this article, the nucleating activity of 2,2'-methylene-bis(4,6-di-tert-butylphenyl) phosphoric acid and its derivatives for isotactic polypropylene (iPP) were investigated with a differential scanning calorimeter (DSC) and polarized light microscope (PLM), and their influence on mechanical properties of polypropylene was also studied. The results showed that the sodium salt (NA7) and the glyceride ester (NA8) of the organic phosphoric acid were of high nucleating efficiency. If 0.4 wt% of NA7 or NA8 was added to PP, the crystallization peak temperature of PP was raised 15degreesC or 11degreesC, respectively, the amount of crystallinity was increased by 3 to 6%, and the crystallization rate was enhanced significantly. The nucleating activity is thermally stable when the mixture of iPP and a nucleating agent was melted and crystallized repeatedly in the DSC. The nucleating agents mentioned above could increase the modulus of the polymer by 20 to about 30% and could increase the flexural strength by 10 to about 20%. :However, a number of other organic phosphates tested have little nucleating effect.