中文摘要：

利用差示扫描量热仪研究了丙烯酸接枝线形低密度聚乙烯（PE-LLD-g-AA）的热学行为，结果表明，与纯线形低密度聚乙烯（PE—LLD）相比，PE-LLD-g-AA的熔融温度（Tm）略有增加，结晶温度（Tc）增加大约4℃，熔融焓（AHm）随AA含量的增加而降低。还利用差示扫描量热仪研究了PE—LLD和PE—LLD-g—AA的等温结晶动力学，用扫描电子显微镜观察了PE—LLD-g—AA等温结晶形态。结果表明，PE-LLD-g-AA的结晶速率大于纯PE—LLD的，随着接枝率的增加，PE-LLD的球晶半径减小，接枝到PE—LLD分子链上的AA分子起到了成核剂的作用。

英文摘要：

The thermal behavior of linear low density polyethylene-grafted-acrylic acid （PE-LLD-g-AA） was investigated using differential scanning calorimety （DSC） and compared with that of neat linear low density polyethylene （PE-LLD）. The melting temperature （Tm） of PE-LLD-g-AA was a little higher and the crystallization temperature （Tc） was about 4 ℃ higher than those neat one. The melting enthalpy （△Hm） decreased with increasing acrylic acid content. The overall crystallization rate of PE-LLD was smaller than that of grafted samples. It showed that the grafted acrylic acid units acted as a nucleating agent. SEM showed that the size of spherulites of PE-LLD-g-AA was smaller than that of PE-LLD.