文献类型：期刊文献

英文题名：Effect of sequence distribution on the non-isothermal crystallization of copolyamide 4/6

作者：Zhang, Yajing[1,2];Cai, Zhili[1,2];Wang, Yibing[1,2];Liu, Jia[1,2];Chen, Tao[2,4];Zhao, Liming[1,2,3]

机构：[1]East China Univ Sci & Technol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Key Lab Biobased Mat Engn, China Natl Light Ind, Shanghai 200237, Peoples R China;[3]Shanghai Collaborat Innovat Ctr Biomfg Technol SC, Shanghai 200237, Peoples R China;[4]East China Univ Sci & Technol, Sch Mat Sci & Engn, Shanghai Key Lab Adv Polymer Mat, Shanghai 200237, Peoples R China

年份：2022

卷号：57

期号：37

起止页码：17883

外文期刊名：JOURNAL OF MATERIALS SCIENCE

收录：;EI(收录号：20224012837800);WOS:【SCI-EXPANDED(收录号:WOS:000863150800001)】；

基金：This work was supported by the National Key R&D Program of China [Grant Number 2017YFB0309302, 2019YFD0901805], the 111 Project [Grant Number B18022], the Fundamental Research Funds for the Central Universities [Grant Number 22221818014], the Open Project Funding of the State Key Laboratory of Bioreactor Engineering, ECUST [Grant Number ZDXM2019], and the Natural Science Foundation of Shanghai, China [Grant Number 21ZR1416000].

语种：英文

外文关键词：Activation analysis - Crystal structure - Crystallinity - Isotherms - Melting point

摘要：Copolyamide 4/6 (PA4/6) was synthesized by copolymerizing 2-pyrrolidone and epsilon-caprolactam; 2-pyrrolidone was obtained from biomass. The melting point of PA4 /6 (140-190 degrees C) was found to be lower than those of both PA4 (265.1 degrees C) and PA6 (220.4 degrees C) for easier processing. For further applications, the effects of the structural sequence composition on the thermal and crystalline properties of the material were investigated. When the content of the PA4 structural sequence S-44 was higher than that of the copolymerized structural sequence S-46, the sequence S-44 exhibits the crystalline behavior of PA4. However, when the S-46 content was similar to the homopolymer sequence content, the melting point and crystallinity reached the respective minima, indicating the most imperfect crystallization. Kinetics analysis of non-isothermal crystallization demonstrated that the crystal grows into a two-dimensional sheet shape, which has the longest crystallization half-time (t(1/2) = 2.64 min) and the highest activation energy (- 10.8 kJ mol(-1)). When the content of the PA6 structural sequence S-66 increases to more than that of S-46, the crystal exhibits three-dimensional spherical growth, t(1/2) decreases to 1.25 min, the activation energy decreases to - 18.0 kJ mol(-1) , and consequently, the crystal structure becomes more perfect. This indicates that S-46 destroys the regular arrangement of molecular chains, whereas the addition of S-66 improves the crystalline structure. [GRAPHICS] .