引用本文:
【打印本页】   【HTML】   【下载PDF全文】   View/Add Comment  【EndNote】   【RefMan】   【BibTex】
←前一篇|后一篇→ 过刊浏览    高级检索
本文已被:浏览 1048次   下载 12 本文二维码信息
码上扫一扫!
分享到: 微信 更多
Crystal Transition Effect on Chain Movement in Nylon 11
Zhu Jun,Zhang Xingyuan*
Author NameAffiliationE-mail
Zhu Jun Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026  
Zhang Xingyuan* Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026 zxym@ustc.edu.cn 
Abstract:
Two crystal forms (α and δ′ form) of nylon 11 were prepared by melting, ice water bath quenching and annealing. The characteristic of chain movement of two forms was investigated using dielectric relaxation spectroscopy in the frequency range from 42 Hz to 5 MHz. The dielectric temperature spectra at different frequencies show that the primary α relaxation corresponding to the chain segment movement is located at higher temperature in α form, indicating the chain segment movement is restricted after δ′→α crystal transition. The activation energy of secondary β relaxation remained almost unchanged for two forms, but the relaxation time was longer and the relaxation strength was weaker for α form, confirming that the local relaxation was also restricted to some extent after δ′→α crystal transition.
Key words:  Nylon 11, Chain movement, Crystal form, Dielectric relaxation
FundProject:
晶型转变对尼龙11分子链运动的影响
朱俊,张兴元*
摘要:
为进一步认识分子链运动与晶型之间的关系,用熔融、冰水淬火和退火等方法制备了α和δ′两种晶型的尼龙11薄膜试样.42 Hz~5 MHz的介电松弛谱显示了两种不同晶型试样的分子运动特征.不同频率下的介电温度谱显示α型结晶中代表分子链段运动的主松弛较δ′型结晶出现在更高温度,说明退火引起的δ′向α晶型转变使分子链段运动受到了限制.研究结果还显示,α和δ′型结晶中分子链局域松弛运动的活化能基本相同,但α型的松弛时间较δ′型的大,松弛强度则较δ′型的小,表明晶型转变使尼龙¨的分子链局域松弛运动也受到了一定程度的抑制
关键词:  尼龙11  分子链运动  晶型  介电松弛
DOI:10.1088/1674-0068/18/4/631-634
分类号: