聚乙烯-g-聚苯乙烯对线性低密度聚乙烯/聚苯乙烯共混物机械性能和发泡行为的影响  

Influence of Polyethylene-g-polystyrene on the Mechanical Properties and Foaming Behavior of Linear Low Density Polyethylene / Polystyrene Blends

作　　者：张光春[1,2] 邱健[1] 邢海平[1] 唐涛[1] 

机构地区：[1]中国科学院长春应用化学研究所高分子物理与化学国家重点实验室,长春130022 [2]中国科学院大学,北京100049

出　　处：《应用化学》2016年第7期756-765,共10页Chinese Journal of Applied Chemistry

基　　金：国家自然科学基金(51233005)项目~~

摘　　要：以通过开环易位聚合、加氢反应和原子转移自由基聚合技术结合制备的聚乙烯-g-聚苯乙烯(PE-gPS)作为增容剂,研究了加入不同PS支链长度的PE-g-PS对于线性低密度聚乙烯/聚苯乙烯(LLDPE/PS)共混物的机械性能和发泡行为的影响。以典型组成m(LLDPE)∶m(PS)=70∶30共混物为例,考察了PE-g-PS对共混物拉伸性能的影响。相对于二元共混物,增容剂的加入使得断裂伸长率、拉伸强度和屈服强度皆提高,且含长PS支链的增容体系提高更明显。采用超临界CO2釜式发泡工艺,考察了PE-g-PS中PS支链长度对共混物发泡行为的影响。结果表明,相对于短PS支链体系,加入PE-g-PS1.59k(PS相对分子质量为1590)后的泡孔结构更加均一,完全没有"缝隙"形貌的出现。当发泡温度降至80℃时,即使存在LLDPE发泡空间限制作用(LLDPE无法发泡),加入支链长度更长的PE-g-PS1.59k后泡孔分布也更加均一。Polyethylene-g-polystyrene（ PE-g-PS） copolymers,which were synthesized by the combination of ring-opening metathesis polymerization（ ROMP）, hydrogenation and atom transfer radical polymerization（ ATRP） method,were utilized to compatibilize linear low density polyethylene /polystyrene（ LLDPE /PS）blends. Using the LLDPE / PS blend in mass ratio of 70∶ 30 as example,the effect of introduction of PE-g-PS on the mechanical properties was investigated. Compared to binary blends,elongation at break,tensile strength and yield strength are improved when the PE-g-PS is introduced. Utilizing PE-g-PS0. 34k（ the subscript0. 34 k represents a relative molecular mass of PS is 340） and PE-g-PS1. 59 kas compatibilizers,the influence of PS branch length on foaming behavior of LLDPE / PS blends was investigated in a batch foaming process with supercritical carbon dioxide as physical foaming agent. Compared to the case containing PE-g-PS0. 34 k,the cellular structure of the foamed blends becomes much more uniform and no large gap appeares with the addition of PE-g-PS1. 59 k. When the foaming temperature is lowered to 80 ℃,confined effect of LLDPE solid around exists,much more uniform cellular structure also appears as PE-g-PS1. 59 kis introduced.

关 键 词：线性低密度聚乙烯/聚苯乙烯共混物 增容剂 机械性能 釜式发泡 支链长度 

分 类 号：O631.1[理学—高分子化学]