中国塑料 ›› 2011, Vol. 25 ›› Issue (02): 72-78 .DOI: 10.19491/j.issn.1001-9278.2011.02.015

• 加工与应用 • 上一篇    下一篇

二异氰酸酯对聚碳酸亚丙酯熔体流变性能的影响

蒋 霞 汪 海 肖荔人 钱庆荣 陈庆华   

  1. 福建师范大学化学与材料学院 福建师范大学化学与材料学院
  • 收稿日期:2010-11-29 修回日期:1900-01-01 出版日期:2011-02-26 发布日期:2011-02-26

Effect of MDI on Melt Rheological Behavior of Poly(propylene carbonate)

  

  • Received:2010-11-29 Revised:1900-01-01 Online:2011-02-26 Published:2011-02-26

摘要: 以4,4-二苯基甲烷二异氰酸酯(MDI)为扩链剂,在转矩流变仪上通过一步法对聚碳酸亚丙酯(PPC)进行了熔融扩链改性。结果表明,随着MDI用量的增加,扩链反应峰和平衡扭矩逐渐增大、平衡时间不断延长;红外光谱分析表明,扩链改性后的PPC在1600 、1535 cm-1处分别出现了苯环的骨架振动吸收峰和-NH的特征吸收峰;旋转流变分析表明,扩链改性后PPC的储能模量、损耗模量和复数黏度均随MDI用量的增加而增加;从Cole-Cole曲线可以看出,随着MDI用量的增加,扩链改性后PPC的相对分子质量逐渐增加,相对分子质量分布变宽,支化度提高;应力松弛测试结果表明,随着MDI用量的增加,松弛时间逐渐增加。

关键词: 聚碳酸亚丙酯, 二异氰酸酯, 流变性能, 扩链

Abstract: In this study, poly(propylene carbonate) (PPC) was chain extended with 4,4-diphenylmethylene diisocyanate(MDI)via melt reaction. On the FTIR spectra, the absorption bands observed at 1600 and 1535 cm-1 were attributed to the vibration of benzene ring and -N-H (amide Ⅱgroups), respectively, suggesting the occurrence of chain extend reaction. The dynamic rheological tests showed that MDI-modified PPC had higher storage and loss moduli and complex viscosity than unmodified PPC. Moreover, modified Cole-Cole plots revealed that the MDI-modified PPC samples possessed higher elasticity, broader molecular weight distribution, longer stress relaxation time than neat PPC.

Key words: poly(propylene carbonate), diphenylmethylene diisocyanate, rheological behavior, chain extension