Reorganization of poly(ethylene terephthalate) structures and conformations to alter properties
Reorganization of poly(ethylene terephthalate) structures and conformations to alter properties
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重组聚对苯二甲酸乙二醇酯结构和构象以改变性能
DOI：
10.1002/polb.21098
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发表时间：
2007
期刊：
影响因子：
--
通讯作者：
A. Tonelli
中科院分区：
文献类型：
--
作者：
Jyotsna Vedula;A. Tonelli
聚对苯二甲酸乙二醇酯(PET)的固态形态、结构和链构象发生了重组/改变，而不是通常的溶液和熔融加工。这是通过两种不同的方法实现的：(1)在客体聚酯和宿主γ-环糊精(γ-CD)之间形成结晶包合物(IC)，然后去除主体γ-CD并使客体聚结(c-PET)；(2)将聚酯从温三氟乙酸溶液中快速沉淀成大量快速搅拌的丙酮(p-PET)。我们先前的观察(FTIR、核磁共振、DSC、X-射线)表明，以这种方式处理的c-PET具有与原始PET(ASR-PET)截然不同的形态、结构和非晶链构象。在可能的情况下进行比较，我们发现c-和p-PET的行为非常相似，但与ASR-PET非常不同。研究发现，重组的c-和p-PETS可以从熔体中反复快速结晶，结晶度高，并且在它们的非晶区具有紧密堆积的链，主要采用高度延伸的扭结构象，这表明没有玻璃化转变行为。最不寻常和有点令人费解的是，观察到它们的对比结构、形貌、构象和热响应与熔融退火无关，即使在Tm以上保持较长时间(小时)后仍保持不变。可以比c-PET大量生产的p-PET被用来测量其他宏观性质，如熔体粘度、密度以及熔压薄膜的应力-应变和热收缩，以与ASR-PET进行比较。©2007 Wiley期刊公司，J Polym Sci第B部分：Polym Phys 45：735-746,2007
The solid-state morphologies, structures, and chain conformations of poly (ethylene terephthalate) (PET) have been reorganized/altered from those normally produced by solution and melt processing. This has been achieved by two distinct methods: (1) formation of a crystalline inclusion compound (IC) between guest PET and host γ-cylodextrin (γ-CD), followed by removal of the host γ-CD and coalescence of the guest PET (c-PET) and (2) rapid precipitation of PET from a warm trifluoracetic acid solution into a large excess of rapidly stirred acetone (p-PET). Our prior observations (FTIR, NMR, DSC, X-ray) demonstrated that c-PET processed in this manner has a morphology, structure, and non-crystalline chain conformations that are quite distinct from those of as-received PET (asr-PET). Where possible to compare, here we find that c- and p-PETs behave very similarly, but very distinctly from asr-PET. The reorganized c- and p-PETs were found to be repeatedly rapidly crystallizable from the melt with a high level of crystallinity, and in their non-crystalline regions to have tightly packed chains predominantly adopting highly extended kink conformations, which evidence no glass-transition behavior. What is most unusual and somewhat puzzling is that their contrasting structures, morphologies, conformations, and thermal responses were observed to be independent of melt annealing, and persisted even after holding both samples above Tm for extended periods (hours). p-PET, which can be produced in larger quantities than c-PET, was utilized to measure additional macroscopic properties, such as melt viscosities, densities, and the stress-strain and thermal shrinkage of melt-pressed films, for comparison to those of asr-PET. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 735–746, 2007
影响因子：
5.5
作者：
H. Choi;T. Ooya;S. Sasaki;N. Yui;Y. Ohya;T. Nakai;T. Ouchi
通讯作者：
H. Choi;T. Ooya;S. Sasaki;N. Yui;Y. Ohya;T. Nakai;T. Ouchi
影响因子：
5.5
作者：
Dong, T;He, Y;Inoue, Y
通讯作者：
Inoue, Y