摘要
以2,5-二甲基-2,5-二(叔丁基过氧基)己烷(DHBP)为过氧化物引发剂,通过双螺杆挤出机制备了高流动性聚丙烯(PP)。研究了DHBP的用量对PP流动性、力学性能、热性能、热稳定性以及流变性能的影响。结果表明,随着引发剂用量的增加,PP的熔体质量流动速率(MFR)迅速增加,流动性得到明显提高,实现了对PP的有效降解;缺口冲击强度、拉伸强度随引发剂用量的增加逐渐降低,引发剂用量达到0.8%时,下降为降解前的50%左右;断裂伸长率随引发剂用量的增加迅速降低,用量超过0.6%以后,断裂伸长率下降到3%以下,表现出明显的脆性断裂。引发剂用量较多时,PP的结晶温度略有升高,结晶度基本保持不变,随引发剂用量增加,熔融峰逐渐由未分开的两个吸热峰演变为分开的两个吸热峰。随引发剂用量增加,PP的初始阶段降解有所提前,降解速率最大值对应的温度虽然有所提前,但总体变化不大;随引发剂用量增加,PP的复数黏度逐渐降低。采用引发剂能实现PP的有效降解。
In this study,the 2,5-dimethyl-2,5-bis(tert-butyl-peroxy)hexane(DHBP)was selected as a peroxide initiator to prepare high fluidity polypropylenes(PP)by twin screw extruder.The effect of DHBP contents on fluidity properties,mechanical properties,thermal properties,thermal stability and rheological properties of PP were investigated.The results show that the melt flow rate(MFR)of PP increases rapidly with the increment of initiator contents.The fluidity of PP is enhanced significantly.And the PP is effectively degraded.The notched impact strength and tensile strength decrease gradually with the increment of initiator contents.When the initiator content reaches 0.8%,the notched impact strength and tensile strength decrease to about 50%of the properties before the degradation.The elongation at break decreases rapidly with the increment of initiator contents.When the content is more than 0.6%,the elongation at break decreases to less than 3%,showing obvious brittle fracture.When the amount of initiator is high,the crystallization temperature of PP increases slightly.And crystallinity remains almost constant.With increasing initiator contents,the melting peak changes gradually from unseparated two endotherms to be resolved into two.With increasing initiator contents,the initial degradation of PP shifts to lower temperature.And the temperature corresponding to the maximum degradation rate shifts to lower temperature.But the change is not significant.The complex viscosity of PP decreases gradually with the increment of initiator contents.The effective degradation of PP is realized by peroxide initiator.
作者
杨锦
柳丽楠
金坤
李西莎
谭志勇
张会轩
YANG Jin;LIU Linan;JIN Kun;LI Xisha;TAN Zhiyong;ZHANG Huixuan(Engineering Research Center of Synthetic Resins and Special Fiber,Ministry of Education,School of Chemical Engineering,Changchun University of Technology,Changchun 130012,China)
出处
《塑料工业》
CAS
CSCD
北大核心
2022年第4期90-93,161,共5页
China Plastics Industry
基金
吉林省发改委产业化项目(2021C036-6)。
