Mechanism of Polymer Crystallization-Material Design Controlled by High Order Structure Formation

聚合物结晶机理-高阶结构形成控制的材料设计

• 批准号: 12127201
• 负责人: OKUI Norimasa
• 金额: $ 14.34万
• 依托单位: Tokyo Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research on Priority Areas
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12127201/
• 关键词: polymer; crystallization; high ordered structure; topology; molecular orientation; diffusion; morphology; epitaxy; 拡散; エピタクシ

We organized five symposiums including international symposium held on 2002 at Mishima. The numbers of participants were more than 150 persons including about 30 oversea participants. These contributed papers were published in the special issue of Journal of Macromolecular Science volume B42 in 2003. In this research project, we have published 213 papers, including 113 general papers, 6 review articles, 4 books, 3 patents and oral presentation for over sea conferences (105) and for Japanese conference (244).The main research results were as follows, It was found that the spinodal decomposition type microphase separation actually occurs in the induction period, owing to orientational fluctuations of the stiff segments. Topological mechanism of the nucleation of polymers has been studied. The direct evidence was shown for the first time that nuclei have been formed during the induction period of the nucleation by means of Small angle X-ray scattering. The molecular weight dependence of t … More he nucleation rate was expressed by power law. The nucleation rate was strongly dependent on wetting force between polymer sample and substrate surface and crystal lattice. It was found that when poly(ethylene oxide) was crystallized on alkali halides, the diffusion-limited aggregates (DLA) were formed. It is the first case of DLA, which was identified in polymer crystallization. The temperature dependence of nucleation rate and growth rate showed bell-shaped curves showing clear maximum points of Imax and Gmax. The MW dependence of Imax and Gmax are scaled and expressed as 1 and -0.5 power of MW, respectively for a chain folding crystallization. Molecular pathways to polymer crystallization and the structures of crystal-melt interfaces were investigated by molecular dynamics simulation. We clearly observe the growth of stacked chain-folded lamellae from the substrates. The growing lamellae have a definite tapered shape, and they show marked thickening growth along the chain axis as well as usual growth perpendicular to it. Crystallization rate of Po]y(carbonate) (PC) in general is very slow, however its rate was accelerated by polymer blending with poly(ethylene oxide) (PEO). During crystallization of the blends, spinodal decomposition was observed and spherulite of PC was observed in PC rich phase. The crystallization of PC was controlled by up-hill diffusion during liquid-liquid phase separation in the polymer blends. Bi-and uni-axial drawing of poly(ethylene terephthalate) (PET) and poly(ethylene 2,6 naphthalene dicarboxylate) (PEN) were performed at various strain rates and temperatures. On-line measurements of drawing stress and birefringence were carried out under several drawing conditions. The stress-optical rule (SOR) was applicable at low birefringence, and the stress-optical coefficient obtained for drawing process was similar to the reported values. Less

2002年在三岛举办了国际研讨会等5次研讨会。参加人数超过150人，其中包括约30名海外参加者。这些论文发表在2003年《高分子科学杂志》B42卷特刊上。本课题共发表论文213篇，其中综合性论文113篇，综述性论文6篇，专著4本，专利3项，海外会议105篇，日本会议244篇，主要研究结果如下：发现诱导期实际上发生了旋节分解型微相分离，这是由于刚性段的取向波动。研究了聚合物成核的拓扑机理。通过小角X射线散射首次给出了在成核诱导期内成核的直接证据。t的分子量依赖性 ...更多信息 成核速率用幂律表示。成核速率强烈依赖于聚合物样品与基底表面和晶格之间的润湿力。研究发现，聚环氧乙烷在碱金属卤化物上结晶时，形成了扩散限制聚集体（DLA）。这是第一例在聚合物结晶中发现的DLA。成核速率和生长速率的温度依赖性呈钟形曲线，显示出明确的Imax和Gmax的最大值点。对于链折叠结晶，Imax和Gmax的MW依赖性被缩放并分别表示为MW的1次幂和-0.5次幂。用分子动力学模拟方法研究了聚合物结晶的分子途径和结晶-熔体界面的结构。我们清楚地观察到从衬底的堆叠链折叠的laminates的生长。聚碳酸酯（PC）的结晶速率一般很慢，但与聚环氧乙烷（PEO）共混后，PC的结晶速率加快。在结晶过程中，共混物的失稳分解和PC的球晶中观察到PC富相。在共混体系中，PC的结晶受液-液相分离过程中的上坡扩散控制。对聚对苯二甲酸乙二酯（PET）和聚2，6萘二甲酸乙二酯（PEN）在不同应变速率和温度下进行了双向拉伸和单向拉伸。在几种拉伸条件下进行了拉伸应力和双折射的在线测量。应力光学定律（SOR）适用于低双折射，拉伸过程中得到的应力光学系数与文献值相近。少

项目成果

K.Kawashima 他: "Morphological changes in flat-on and edge-on lamellae of PESU crystallized from molten thin films"J.Macromolecular Sci.. B42. 889-899 (2003)

K. Kawashima 等人：“从熔融薄膜中结晶的 PESU 平铺和边缘片层的形态变化”J. Macromolecular Sci.. B42 (2003)。

S.Umemoto 他: "Structure development of ployactides with various, d-lactide contents in the high speed melt spinning process"J.Macromolecular Sci.. B42. 59-75 (2003)

S. Umemoto 等人：“高速熔融纺丝过程中具有不同 d-丙交酯含量的聚丙交酯的结构开发”J. Macromolecular Sci.. B42 (2003)。

M.Hocquet 他: "Lamellar and Crystalline Layer Thickness of Single Crystals of Narrow Molecular Weight Fractions of Linear Polyethlene."Macromolecules. 35. 5025-5033 (2003)

M.Hocquet 等人：“线性聚乙烯窄分子量级分单晶的层状和结晶层厚度”。《高分子》35. 5025-5033 (2003)

A.Toda: "Kinetic Barrier of Pinning in Polymer Crystallization : Rate Equation Approach"J. Chem. Phys.. 118. 8446-8455 (2003)

A.Toda：“聚合物结晶中钉扎的动力学势垒：速率方程方法”J。

A.Koyama: "Molecular dynamics studies on polymer crystallization from a stretched amorphous state"J.Macromol. Sci.. B42. 821-831 (2003)

A.Koyama：“聚合物从拉伸非晶态结晶的分子动力学研究”J.Macromol。