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Investigation on chain structure of LLDPE obtained by ethylene in-situ copolymerization with DSC and XRD 被引量：3

Investigation on chain structure of LLDPE obtained by ethylene in-situ copolymerization with DSC and XRD
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摘要 Thermal segregations of LLDPE were treated with successive self-nucleation/annealing (SSA) on dif-ferential scanning calorimetry (DSC). Information on molecular heterogeneity of LLDPE was obtained. After SSA was treated, the multiple endothermic peaks were observed in the DSC thermograms during heating experiment. It is obtained that the thickness of different lamellas formed by segments of vari-ous lengths was 4―10 nm. X-ray diffraction (XRD) results showed that the crystallites dimensions of various reflections were about several dozens of nanometers. The ethylene/α-olefin copolymers and the copolymer via in-situ copolymerization were similar to each other for molecular heterogeneity and XRD characteristics, which revealed that it was possible to use the ethylene/α-olefin copolymers to simulate the copolymer via in-situ copolymerization of ethylene to simplify the complexity of the structure of the ethylene in-situ copolymer. Thermal segregations of LLDPE were treated with successive self-nucleation/annealing （SSA） on differential scanning calorimetry （DSC）. Information on molecular heterogeneity of LLDPE was obtained. After SSA was treated, the multiple endothermic peaks were observed in the DSC thermograms during heating experiment. It is obtained that the thickness of different lamellas formed by segments of various lengths was 4-10 nm. X-ray diffraction （XRD） results showed that the crystallites dimensions of various reflections were about several dozens of nanometers. The ethylene/a-olefin copolymers and the copolymer via in-situ copolymerization were similar to each other for molecular heterogeneity and XRD characteristics, which revealed that it was possible to use the ethylene/α-olefln copolymers to simulate the copolymer via in-situ copolymerization of ethylene to simplify the complexity of the structure of the ethylene in-situ copolymer.
作者 WANG YanJie YAN WeiDong
机构地区 Institute of Polymer Science and Engineering
出处 《Chinese Science Bulletin》 SCIE EI CAS 2007年第6期736-742,共7页
基金 Supported by the National Natural Science Foundation of China (Grant No. 50573018) Doctoral Foundation of Hebei Province (Grant No. 05547003D-6)
关键词 乙烯 现场共聚合 LLDPE 链状结构 XRD DSC LLDPE via in-situ copolymerization, ethylene and α-olefin copolymers, thermal segregation, XRD, DSC
分类号 O632.12 [理学—高分子化学]
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共引文献8

同被引文献19

  • 1谢侃,唐岩,李延亮,王群涛,张桂云,张佐光.聚乙烯管材料抵抗慢速裂纹扩展性能研究[J].中国塑料,2005,19(3):20-23. 被引量：12
  • 2唐岩,王群涛,石志俭,谢建玲,戚思清,毕丽景.PE100级管材专用树脂的开发[J].合成树脂及塑料,2005,22(5):5-8. 被引量：15
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Chinese Science Bulletin
2007年 第6期

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