抗冲聚丙烯共聚物熔体结构演化的动态流变学表征  

THE DYNAMIC RHEOLOGICAL CHARACTERIZATION OF STRUCTURE DEVELOPMENT FOR IMPACT POLYPROPYLENE COPOLYMER MELT

作　　者：谢严莉[1] 上官勇刚[1] 郑强[1] 

机构地区：[1]浙江大学高分子科学与工程学系高分子合成与功能构造教育部重点实验室,杭州310027

出　　处：《高分子学报》2008年第1期93-96,共4页Acta Polymerica Sinica

基　　金：国家基础研究专项经费(项目号2005CB623800);国家自然科学基金(基金号50603023)资助项目

摘　　要：用动态流变学方法研究了抗冲聚丙烯共聚物(IPC)熔体的流变行为.通过探讨温度、抗氧剂、氧气的存在对其熔体动态粘弹响应的影响,对IPC熔体结构的演化过程进行了描述.随温度的升高,IPC熔体的动态粘弹响应明显改变,低频率(ω)区域动态储能模量(G′)与ω的对数关系lgG′-lgω呈现平台特征;加入复合抗氧剂B215或在N2气氛下,在一定的时间范围内,IPC的特征粘弹行为完全消失,呈现均相体系的流变响应特征.低ω区域粘弹函数对IPC的结构变化存在敏感响应.通过改变温度、添加抗氧剂以及N2保护,获得了IPC熔体因降解与交联反应所引起的结构改变的信息.The rheological behaviors of impact polypropylene copolymer （IPC） were studied by means of dynamicrheological tests. The dynamic rheological measurements were conducted on an Advanced Rheometric Expansion System with parallel plate geometry of 25 mm diameter under air and N2, respectively. Two sorts of tests were performed under conditions as follows： （1） isothermal frequency sweeps from 100 rad·s^-1 to 0.01 rad·s^-1 atdifferent temperatures from 190℃ to 230℃ in steps of 20℃ ;（2） isothermal time sweeps at a frequency of 0.05 rad·s^-1 and a strain of 5 % under different temperatures from 190℃ to 230℃. The development of melt structure for IPC was probed through examining the influence of temperature, atmosphere and additive antioxidant on dynamic rheological functions. Results reveal that the rheological functions vary with the increase of temperature. The second plateau appears in the logarithmic plots of the dynamic storage modulus versus frequency, lgG′-lgω, in the low ω range. Moreover, for the IPC samples exposed to N2 or blending certain time period, being a representation of the rheological rheological functions in the low ω range can sensitively reflect IPC. with antioxidant, this second plateau disappears in a properties for homogeneous polymers. Furthermore, the oxidation-induced degradation and crosslinking of IPC.

关 键 词：抗冲聚丙烯共聚物 动态流变行为 结构 降解 交联 

分 类 号：O632.1[理学—高分子化学]