权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Relations between microscopic crosslinking structure and heterogeneity of physical gels and macroscopic properties.

微观交联结构与物理凝胶的异质性和宏观性质之间的关系。

基本信息

批准号：
10305070
负责人：
NEMOTO Norio
金额：
$ 25.47万
依托单位：
KYUSHU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A).
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 2000
项目状态：
已结题

项目摘要

We designed an infrared spectrometer for dichroism measurement under microscopic scope of 10 μ m size during elongation of samples of gels or films in order to observe molecular motions responding to stimulus of elongational deformation.We measured infrared dichroism change with elongation for two types of polyethyelene gels with different type of crosslink regions of microcrystallite. One is a swelling gel prepared by swelling the film in tetralin as solvent. The other is a solution gel prepared by gradually cooling a solution obtained by heating the swelling gel. The swelling gel deformed by two steps ; In first step, gel deformed by the rotation of crosslink region consisting of lamellae, and in second step crystalline and non-crystalline regions were oriented by elongation. On the other hand, the solution gels deformed by One step, in which crystalline and non-crystalline regions were simultaneously oriented by elongation.We investigated the deformation behavior of polypropylene fi … More lm including giant spherulites surrounded by microcrystallite region. When elongation proceeded, microcrystallie region was oriented largely while the giant spherulites were scarcely oriented, which means that the spherulite is fairly rigid in comparison with the microcrystalline region. In the microcrystalline region, it almost keeps unoriented state before finishing yield phenomenon and rapidly oriented just after the yield point. And then the orientation gradually proceeded with further elongation. As for the giant spherulite region, in α_ crystals, separation and entanglement of lamellae occurred for each bundles of crystals. α_<mix> crystals did not easily deform because child lamellae prevent from deformation of parent lamellae. β crystal was fragile and entanglement of twisted lamella was easily disentangled by small stress. α crystals were fairly isolated from the microcrystalline region, while β crystals entangled with microcrystalline region and deformation of spherulite in largely influence to the deformation of the system. Less

为了观察分子在拉伸变形刺激下的运动，我们设计了一台在10 μ m显微镜下测量凝胶或薄膜样品拉伸过程中二向色性的红外光谱仪，测量了两种具有不同微晶交联区的聚乙烯凝胶的红外二向色性随拉伸的变化。一种是以四氢萘为溶剂，通过溶胀膜制备的溶胀凝胶。另一种是通过逐渐冷却通过加热溶胀凝胶获得的溶液而制备的溶液凝胶。溶胀凝胶的变形分两步进行，第一步是由层状结构组成的交联区旋转变形，第二步是晶区和非晶区伸长取向。另一方面，溶液凝胶的变形是一步完成的，其中结晶区和非结晶区同时被拉伸而取向。 ...更多信息 lm包括被微晶区域包围的巨球晶。当拉伸进行时，微晶区域大部分取向，而巨球晶几乎没有取向，这意味着球晶与微晶区域相比相当刚性。在微晶区，屈服现象结束前几乎保持无取向状态，屈服点后迅速取向。然后，随着进一步的伸长，取向逐渐进行。在巨球晶区，α_晶体中，每束晶体都发生了层片的分离和缠结。由于<mix>子层阻止了母层的变形，α_晶体不易变形。β晶体易碎，扭曲片层的缠结在较小的应力作用下容易解除。α晶体与微晶区相互隔离，β晶体与微晶区相互纠缠，球晶的形变对体系的形变影响较大。少