Abstract : positron spectroscopy is a new and sensitive microanalytical probe for characterization of polymer microstructures . we report recent advances in this area , including studies on the free volume properties , structural transition , miscibility of blending polymers , physical aging , doping of functional polymers , interfacial interaction of multiphase polymers , etc 文摘:简要介绍了近年来正电子谱学在聚合物微结构研究中的主要应用及进展.大量实验事实表明,正电子谱学是表征高聚物微结构的极灵敏方法
In the volume change study , we found appropriate temperature is helpful for shrinkage control , and different lpas have different shrinkage control effects due to their dipole moment , tg , miscibility with upr and morphology after blending . there existed an optimal concentration range of poly ( vinyl acetate ) based lpas for shrinkage control . lpa was effective for shrinkage compensation in this range , on the other hand , lpa only acted as filler and the low profile effect vanished out of this range , however , for polystyrene based lpa , the more concentration the better shrinkage control 在膨胀研究中,发现适当的温度条件更有利于upr达到好的收缩控制效果;不同类型的lpa随着偶极矩、玻璃化温度、与upr的相容性、与upr的混合形态的不同,表现出不同的收缩控制效果;聚醋酸乙烯酯类的lpa - a存在一个最佳收缩控制的浓度范围,在这个范围之内, lpa起到补偿收缩的作用;而在这个范围之外, lpa的作用仅相当于填料,不能起到收缩控制。
However , it is not easy to incorporate large n concentration in gap due to the large differences in lattice structure ( gan belongs to wurtzite structure while gap zinc blende structure ) and in lattice constant ( ~ 20 % ) between gan and gap , which will lead to an extremely large miscibility gap 然而要在gap中实现高浓度的掺氮并不容易。这主要是由于gap和gan之间较大的物理特性的差异,特别是晶格结构和晶格常数的差异,使得gap和gan存在较大的可混溶性间隙,从而难以生长高质量的高掺氮的gap材料。
This offered by the three - dimensional quality alone jade carvings from natural a cargo , quality intensive , the quality of the jade plane delicate , smooth shine , comfortable and pleasant attendants evenly falling to the entire county , the mysterious violet nothing left to win , and chui hue seepage miscibility , the eagle more vibrant and vivid 此一款由精品独玉立体巧雕而成,天然a货,质是坚密,玉质冰爽细腻,光滑亮泽,清爽宜人的翠色均匀地飘洒在整个玉体,神秘的紫罗兰色精光闪现,与翠色相渗相溶,使雄鹰更显鲜活生动。
In addition , chondroitin sulfate / chitosan composite films are self - assembled through electrostatic attraction on the positively charges mica substrate . the interaction and mechanism of forming the composite films were introduced . when the concentration of chitosan is 5 mg / ml and the concentration of chondroitin sulfate is 1 mg / ml , the composite films exhibited a good miscibility at a molecular scale . this kind of composite films is promising in the field of medical materials 另外,也研究了草酸钙在硫酸软骨素自组装膜上受控凝集结晶的现象,发现当硫酸软骨素的浓度为1 . 0mg ml时在云母表面形成的网状基底可以诱导过饱和的草酸钙溶液凝集结晶形成liesegang环,为深入研究尿结石中环结构的形成提供了一定的实验依据。
Then properties of the polysilane - polyacrylate gradient film were characterized . the mechanism of film forming process of polysilane - polyacrylate fgm was probed into as well . the testing results indicated that adding p ( mma - co - ptris ) of different can improve the poor miscibility of pmma and ptris because p ( mma - co - ptris ) contained both pmma chains and organosilicone chains which joint pmma and ptris as a bridge 通过测试有机硅聚合物-聚丙烯酸酯共混梯度膜的结构,发现ptris和pmma的相容性较差,加入不同聚合比例的共聚物p ( mma - co - tris )后相容性得到改善,并可以得到一面是丙烯酸酯端;然后结构渐变成有机硅聚合物端的梯度膜。
Abstract : new progress of raman technique in the research on macromolecule science recent years was summarized in this paper including the miscibility of polymer blends , the mechanism of surface plasticization , the monitoring of stress and strain relaxation process , raman imaging , the monitoring of polymerization , determination of curing process , the monitoring of crystal process in polymer and the study on the structure of water and intra - and inter molecular interactions in the solution of polymer and gelatin . a great deal of research of raman technique in this aspects were also summarized 文摘:综述了拉曼技术在高分子科学研究中近年来的最新进展,包括聚合物共混物的相容性、表面增塑机理、应力松弛和应变过程的监测以及拉曼成像、聚合反应监控、固化过程监测、聚合物结晶过程监控、聚合物水溶液和凝胶体系中水的结构及分子间、分子内相互作用力的研究。