The Influence of Ethyl Branch on Formation of Shish-Kebab Crystals in Bimodal Polyethylene under Shear at Low Temperature
The Influence of Ethyl Branch on Formation of Shish-Kebab Crystals in Bimodal Polyethylene under Shear at Low Temperature
复制标题
低温剪切下乙基支链对双峰聚乙烯中Shish-Kebab晶体形成的影响
DOI：
10.1007/s10118-021-2568-1
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发表时间：
2021-05
影响因子：
4.3
通讯作者：
Hsiao Benjamin S.
中科院分区：
文献类型：
--
作者：
Wang Zong-Bao;Mao Yi-Min;Li Xu-Ke;Li Yi-Guo;Jarumaneeroj Chatchai;Thitisak Boonyakeat;Tiyapiboonchaiya Piyawanz;Rungswang Wonchalerm;Hsiao Benjamin S.
研究了不同乙基支含量的高分子量双峰聚乙烯体系对羊肉串晶体形成的影响。采用小角x射线散射（SAXS）和广角x射线衍射（WAXD）技术，对低温低剪切速率单剪切模式下羊肉串结构的形成和演化进行了监测。在129℃的剪切温度下，只有不带分支的双峰PE形成了羊肉串晶体，并且随着结晶时间的延长，羊肉串晶体的长度增加，而带分支的双峰PE在相同条件下没有观察到羊肉串晶体。无分支的双峰聚乙烯结晶度随时间增加可达7%以上，而有乙基分支的双峰聚乙烯结晶度持续增加，可达23%以上。无分支双峰PE的Hermans取向因子增加到0.60，而有乙基分支双峰PE的Hermans取向因子仅增加到0.15以下。本研究表明，在129℃低温下形成的羊肉串晶体是由于没有分支的双峰聚乙烯在剪切作用下纠缠链的拉伸。乙基支双峰聚乙烯仅形成部分取向的层状晶体。在剪切温度高于熔点、接近熔点和低于熔点时，双峰PE样品的卷曲-拉伸转变和拉伸网络的不同机制通过改变剪切温度来调制shish晶体的形成。
Formation of shish-kebab crystals using a bimodal polyethylene system containing high molecular weight (HMW) component with different ethyl branch contents was investigated.In situsmall-angle X-ray scattering (SAXS) and wide-angle X-ray diffraction (WAXD) techniques were used to monitor the formation and evolution of shish-kebab structure sheared at low temperature in simple shear mode and low rate. Only the bimodal PE with no branch formed shish-kebab crystals at the shear temperature of 129 °C, and the shish length increased with the crystallization time, while bimodal PE with branch has no observable shish under the same conditions. The degree of crystallization for bimodal PE with no branch increased with time up to above 7%, while those with ethyl branch increased continually up to above 23%. Furthermore, bimodal PE’s Hermans orientation factor with no branch increased to 0.60, while those with ethyl branch only increased to a value below 0.15. This study indicated that the shish-kebab crystal formed at the low temperature of 129 °C is due to the stretch of entangled chains under shear for the bimodal PE with no branch. Only partly oriented lamellar crystals were formed for the bimodal PE with ethyl branch. All the results at the shear temperatures higher, closed to, and lower than the melting point, the modulation of shish crystals formation owing to different mechanisms of the coil-stretch transition and the stretched network by changing shear temperature was achieved in the bimodal PE samples.
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影响因子：
6.1
作者：
PERRET, R;RULAND, W
通讯作者：
RULAND, W
影响因子：
4.6
作者：
MACKLEY, MR;KELLER, A
通讯作者：
KELLER, A
高剪切温度下短链支化对双峰聚乙烯剪切诱导晶体形成的影响
影响因子：
6
作者：
Jiang Libin;An Minfang;Wu Feng;Miao Weijun;Wang Zongbao;Zhang Yaopeng;Hsiao Benjamin S.
通讯作者：
Hsiao Benjamin S.
烤肉串形成的临界应变
影响因子：
5.5
作者：
Tingzi Yan;Shiwang Cheng;Yuanhua Cong;Zijian Wang;Liangbin Li;Xiuhong Li;Guoqiang Pan;Yuye Fang;Fenggang Bian;Baijin Zhao
通讯作者：
Baijin Zhao
影响因子：
64.8
作者：
F. L. BINSBERGEN-
通讯作者：
F. L. BINSBERGEN-