A topochemical study of the polymerization of terephthalonitrile oxide
A topochemical study of the polymerization of terephthalonitrile oxide
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对苯二甲腈氧化物聚合的拓扑化学研究
DOI：
10.1002/pol.1967.110050405
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发表时间：
1967
期刊：
影响因子：
--
通讯作者：
S. Fujimoto
中科院分区：
文献类型：
--
作者：
S. Fujimoto
也就是说，在普通有机介质中，单体的氧化腈基团的行为就像单腈氧化物一样，在聚合物链中产生氧化呋咱环，而在单体晶体中，它们以相反的方向偶联，产生恶唑肟环，后者很少预期在特殊情况的酸性条件下形成（2）。腈氧化物的环加成反应得到固态恶唑肟以前从未报道过。本文还指出了固相聚合的一些特点，如要求较高的聚合温度和所得聚合物的特性粘度较高。在低于65 ℃的温度下不发生固态聚合。通常在1000 ℃下进行。在相同条件下，由较好的单体晶体比由较差的晶体获得更高分子量的聚合物。我们建议注意单体晶体中氧化腈基团的拓扑化学行为。单体和聚合物的红外光谱如图1所示。单体的光谱I表明CrN-0基团的线性结构和分子的高度对称性，不存在可归因于结构不对称性的复杂的衍射。通过固相法获得的聚合物的光谱I11显示出与通过溶液法获得的聚合物的光谱I1的若干不一致。在2260厘米处有微弱的吸收。可归因于少量的通过氧化腈基团的重排产生的异氰酸酯基团，
Namely, in ordinaly organic media the nitrile oxide groups of the monomer behaved just as mononitrile oxides do, to give furoxan rings in the polymer chain, while in the monomer crystals they were coupled in the reverse direction to give oxazoxime rings, the latter being rarely expected to form in acidic conditions of special cases (2). The cycloaddition of nitrile oxides giving oxazoximes in the solid state had never been reported before. We also have pointed out some characteristics of the solid-state polymerization, eg, higher polymerization temperatures re-quired and higher intrinsic viscosities of the polymers obtained. The polymerization in the solid state did not take place below 65OC. and normally proceeded at looo C. Higher molecular weight polymers were obtained from better crystals of the monomer than from poorer crystals under the same conditions. We have suggested taking note of the topochemical behavior of the nitrile oxide groups in the monomer crystal. The infrared spectra of the monomer and the polymers are shown in Figure 1. The spectrum I of the monomer indicated a linear structure for the CrN-0 group and a high symmetry for the molecule, complex absorptions assignable to asymmetry of the structure being absent. The spectrum I11 of the polymer obtained by the solid process showed several disagreements with the spectrum I1 of the one by the solution process. A weak absorption at 2260 cm.-', assignable to a small amount of isocyanate group produced by the rearrangement of the nitrile oxide group,