摘要
对冲击性能有差异的3种无规共聚聚丙烯(PP-R)进行了结构表征。用扫描电镜进行断面形貌分析,发现其中 PPR2的断裂形貌为脆性断裂,PPR1为韧性断裂,PPR3界于二者之间;用偏光显微镜进行观察时,发现 PPR2的球晶多而大,PPR1的球晶小且少于 PPR2,而 PPR3为多而小的球晶。结合偏光和断裂形貌能说明这3种样品冲击强度的差异是由于乙烯插人到丙烯链中均匀性的不同所引起,乙烯在丙烯链中分布不同可导致结晶颗粒大小不同,这决定了样品的冲击强度的高低。这种现象在用核磁共振波谱仪、示差扫描量热仪对样品进行观察时也可以反应出来。
Structure of three kinds of industrial polypropylene random copolymer（PP-R） with different impact property was characterised in this paper. Morphology of fracture shown by SEM indicates that PPR2 has brittleness fracture, PPR1 has toughness fracture and PPR3 has both brittleness fracture and toughness fracture. Results of polarizing microscope observation show that PPR1 has more and bigger spherulite than PPR2 has, and PPR3 has a large number of small spherulites. From the results of SEM and polarizing microscope observation, we can safely draw the conclusion that existing of a small sum of insufficiently modified PP in samples leads to the different impact property of three kinds of industrial PP-R. Insufficiently modified PP can also be observed by 13C-NMR and DSC characterisation.
出处
《中国塑料》
CAS
CSCD
北大核心
2008年第9期85-88,共4页
China Plastics
关键词
无规共聚聚丙烯
结构表征
球晶
polypropylene random copolymer
structural characterisation
spherulite
