Monomer-to-Polymer Phase Transition of Diacetylenes with gamma-Rays

伽马射线下丁二炔单体到聚合物的相变

基本信息

批准号：
62540239
负责人：
MATSUYAMA Tomochika
金额：
$ 0.38万
依托单位：
KYOTO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1987
资助国家：
日本
起止时间：
1987 至 1989
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-62540239/
关键词：
Diacetylene Polydiacetylene Topochemical polymerization Oriented polymers Color change Solid state polymerization Single crystals of polymers First order phase transition 放射線重合相転移ジアセチセン DCH TCDU 共役系高分子単結晶

项目摘要

1. The monomer crystal of 1,6-di(N-carbazolyl)-2,4-hexadiyne (DCH) has the lattice parameters which predict a low reactivity in solid state polymerization. Despite the prediction, DCH monomer crystals can be converted to fully conjugated polymer crystals upon exposure to gamma-rays. This is due to the transformation of the crystal from a less-reactive phase to a more-reactive phase at the level of about 30% polymerization. This phase transformation is abruptly achieved without destruction of the crystal. The fact implies that a topochemical 1,4-addition reaction leading to the polymerization under gamma-irradiation proceeds homogeneously in both phases by the formation of solid solutions.2. The crystal of DCH monomer undergoes inherent phase transition (IPT). It has been determined that the temperature and the heat of IPT are 148K and 1.2 kcal/mol in as-grown DCH crystals, respectively. When the crystals were gamma-irradiated at room temperature, it was found that all lattice parameter … More s change gradually with gamma-ray dosage in the aforementioned less-reactive phase. In addition to the above fact it was also found in the less-reactive phase that the transition point of IPT is shifted to the temperature side lower than 148K with decreasing the heat of IPT under gamma-irradiation and that the color of the crystal is red below and blue above the temperature of IPT. The temperature shift of IPT, the decrement of heat for IPT and the color change at IPT are interpreted in terms of the concept of strain field induced by the formation of polymers within the monomer columns.3. The asymmetric monomers of 1-(N-carbazolyl)-6-(4'-methyl terephthaloyl)- 2,4-hexadiyne and 1-(N-carbazolyl)-6-(2',4'-dinitrophenyl ether)-2,4- hexadiyne were synthesized. Their crystal structures were determined with x-ray diffraction analysis. The present crystals showed neither topochemical polymerization nor phase transition. The non-polymerizability of the crystals is explained with monomer packing parameters and is consistent with the Baughman's model. Less

1. 1,6-二(N-咔唑基)-2,4-己二炔(DCH)单体晶体的晶格参数预测其在固态聚合中的反应性较低，尽管有这样的预测，但DCH单体晶体可以转化为。暴露于伽马射线后，聚合物晶体完全共轭，这是由于晶体从反应性较低的相转变为反应性较高的相，其水平约为 30%。这种相变是在不破坏晶体的情况下突然实现的。这一事实表明，在γ-辐射下导致聚合的拓扑化学1,4-加成反应通过形成固溶体在两个相中均匀地进行。已确定，在生长的 DCH 晶体中，IPT 的温度和热量分别为 148K 和 1.2 kcal/mol。在室温下对晶体进行伽马射线照射，发现在上述低反应相中，所有晶格参数都随着伽马射线剂量的变化而逐渐变化。除了上述事实之外，在低反应相中也发现了这一点。在γ射线照射下，随着IPT热量的减少，IPT的转变点向低于148K的温度方向移动，并且在IPT温度以下晶体颜色为红色，在IPT温度以上晶体颜色为蓝色。 IPT、IPT热量的减少和IPT颜色的变化是根据单体柱内聚合物形成引起的应变场的概念来解释的。3．1-(N-咔唑基)-6的不对称单体。 -(4'-甲基对苯二甲酰基)-2,4-己二炔和1-(N-咔唑基)-6-(2',4'-二硝基苯基)合成了(乙醚)-2,4-己二炔。通过X射线衍射分析确定了它们的晶体结构，该晶体既没有表现出拓扑化学聚合，也没有表现出相变。晶体的不可聚合性与单体堆积参数相一致。与鲍曼模型相比。