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Dynamics of self-organization in crystalline polymers

结晶聚合物自组织动力学

基本信息

批准号：
11640378
负责人：
TODA Akihiko
金额：
$ 0.7万
依托单位：
Hiroshima University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11640378/
关键词：
polymer single crystal self-organization higher order structure banded spherulite three-dimensional shape

项目摘要

We have examined the dynamics of self-organization appearing in the higher order structure of crystalline polymers which is a typical soft-condensed matter. Crystallization of polymers organizes complex and various structures which cannot be formed by small molecules. As a typical example, it is well known that a periodic pattern of concentric banding is formed during the crystallization of polymer spherulite from the melt. In the present research, utilizing the observation by transmission electron microscopy, we have clarified the physical mechanism of twist in the lamellar crystallites of polymer, which is the basic structure producing the periodic pattern. We have examined the morphology of poly (vinylidene fluoride) (PVDF) single crystals grown from the melt and from the blend with poly (ethyl acrylate) (PEA) : PVDF/PEA = 0.5/99.5 and 30/70 by weight ratio. Three-dimensional morphology of single crystals was examined by transmission electron microscopy (bright field, dark field and diffraction) with a tilting stage. For all cases, the titling of chains by 26 degrees to the fold surface has been confirmed. Three-dimensional shape of all crystals was chair type for 30/70 blend and pure PVDF.In chair crystals, spiral terraces keep the handedness in each growth direction. From those evidences, we have proposed that the chair crystals with consecutive creation of spiral terraces of the same sense are responsible for the twisting relationship between crystallites in the radial direction of banded spherulites. Based on this conclusion, we have confirmed the consistence in the handedness of twisting in the banded spherulites by the observation with atomic force microscopy.

本文研究了典型软凝聚态结晶聚合物高阶结构中的自组织动力学。聚合物的结晶形成了小分子无法形成的复杂多样的结构。作为一个典型的例子，众所周知，在聚合物球粒从熔体结晶过程中形成一个周期性的同心带。在本研究中，我们利用透射电镜观察，阐明了聚合物片层晶体中扭曲的物理机制，这是产生周期性图案的基本结构。我们研究了从熔体和与聚丙烯酸乙酯（PEA）共混物中生长的聚偏氟乙烯（PVDF）单晶的形态：PVDF/PEA = 0.5/99.5和30/70的重量比。用透射电子显微镜（明光场、暗场和衍射）观察单晶的三维形貌。在所有的情况下，链向褶皱表面倾斜26度已被证实。对于30/70混纺和纯PVDF，所有晶体的三维形状均为椅型。在椅子晶体中，螺旋梯田在每个生长方向上保持手性。根据这些证据，我们提出具有相同意义的螺旋梯田的连续形成的椅子晶体是造成带状球晶径向扭曲关系的原因。在此基础上，通过原子力显微镜的观察，证实了带状球晶的旋向性是一致的。