Synthesis of novel reactive polymers by allylboration polymerization

采用三烯丙基硼烷、三甲基硼烷、烯丙基二烷基硼烷等双氰基化合物与烯丙基硼烷加成制备了新型含硼聚合物。当三烯丙基硼烷和异苯二腈在0℃下进行聚合时，反应混合物在几分钟内成为均匀的液体。反应1天后，得到玻璃状聚合物。通过GPC估计所得聚合物的分子量，M_n和M_w分别为14000和25700。通过^1H-， ^<11> - nmr和IR分析证实了聚合物的结构。对所得聚合物的空气稳定性和热稳定性进行了测试。即使在惰性气氛下，大部分含硼聚合物在储存时也变得不溶。将聚合物加热到140℃左右，发生不可逆的化学反应（即进一步的烯丙基硼化反应），聚合物变得不溶，同时其结构也发生了变化。与双氰基单体氢硼酸聚合制备的聚合物类似，这些聚合物在热解后会产生一些残留物。用三甲基硼烷进行了烯丙基硼化聚合。当在室温下批量聚合时，烯丙基硼化反应立即完成，但所得聚合物的分子量增加非常缓慢。与三烯基硼烷相比，聚合速度较慢，这是造成位阻亚硼烷二聚化缓慢的原因。对于芳香二氰单体，如二苯二腈，由于二聚化不足，与三烯硼烷的反应产生了低聚物，这可以通过红外测量清楚地看到。所得聚合物的结构通过光谱测量得到了证实。从三甲基硼烷中得到的含硼聚合物与从三烯基硼烷中得到的聚合物相比，具有一定的稳定性。少

Novel boron-containing polymers were obtained by polyaddition between dicyano compounds and allylboranes such as triallylborane, trimethallylborane, and allyldialkylboranes.When polymerization between triallylborane and isophthalonitrile was carried out in bulk at 0ﾟC,the reaction mixture became homogeneous liquid within several minutes. After the reaction for 1 day, a glassy polymer was obtained. The molecular weight of the resulting polymer was estimated by GPC,from which M_n and M_w were found to be 14,000 and 25,700, respectively. The structure of the polymer was confirmed by ^1H-, ^<11>B-NMR,and IR analyzes. The air- as well as thermal stabilities of the obtained polymers were examined. Most part of the resulting boron-containing polymers became insoluble upon the storage even under the inert atmosphere. By heating the polymer around 140ﾟC,an irreversible chemical reaction (i.e., further allylboration reaction) took place and the polymer became insoluble accompanying its structura … More l change. Similarly to the polymers prepared by hydroboration polymerization of dicyano monomers, these polymers gave some residue after pyrolysis.Allylboration polymerization was also examined with trimethallylborane. When polymerizations of alpha, omega-dicyanoalkanes were carried out in bulk at ambient temperature, the allylboration reactions were completed instantly, but the molecular weights of the resulting polymers increased very slowly. The siow rate of polymerization in comparison with that of triallylborane was responsible for the slow dimerization of sterically hindered iminoboranes. In the case of aromatic dicyano monomers such as isophthalonitrile, the reaction with triallyborane produced oligomers as a results of the insufficient dimerization that could be clearly followed by its IR measurement. The structures of the obtained polymers were confirmed by their spectroscopic measurements. The boron-containing polymers from trimethallylborane were found to be somewhat stable in comparison with those obtained from triallylborane. Less