摘要
通过在β改性无规共聚聚丙烯(PPR)中添加少量的等规聚丙烯(iPP)使PPR的β结晶能力得到显著提高。结果表明,进行条件优化后,PPR的β晶体相对含量增加到92.4%,其β结晶能力提高61.5%;iPP首先形成β晶核,进一步诱导PPR产生β晶;由于高含量的β晶体,PPR的韧性大幅度提高,冲击强度从22.8 kJ/m^2提高到45.9 kJ/m^2,断裂伸长率达到574.4%,是纯PPR断裂伸长率的4倍;iPP自身刚性和高含量β晶体具有协同作用,使得共混体系的拉伸强度几乎保持不变。
This study reported an enhancement of crystallization capability for the β-crystal-modified polypropylene random copolymer （ PPR） by incorporation of small amount of isotactic polypropylene （iPP）. The investigations indicated that the relative content of β-form crystals was increased to 92. 4 % through an optimization of experimental conditions, and the β-form crystallization capability also increased by 61. 5 %. The investigation on crystal growth process indicated that iPP formed β-crystal nucleus at first and then induced the β-form crystallization for PPR. The high content of β-form crystals resulted in a significant great improvement in impact toughness. The impact strength obtained an increase from 22. 8 to 45. 9 kj/m2 while the elongation at break increased to 574. 4 %, which was almost by a factor of three compared with pure PPR. There is a synergistic effect between the rigidity of iPP and the high content of β-form crystals, leading to little change in tensile strength of PPR/iPP compounds.
出处
《中国塑料》
CAS
CSCD
北大核心
2017年第2期56-64,共9页
China Plastics
基金
重庆市质量技术监督局科技攻关资助项目(CQZJKY2014031)
重庆市质量技术监督局基础科学研究资助项目(CQZJKY2015016)
关键词
等规聚丙烯
无规共聚聚丙烯
β改性
结晶
isotactic polypropylene
polypropylene random copolymer
β-modification
crystalliza-tion
