Solid‐state photochemical generation of polymeric polyradicals: Poly(4‐vinylphenoxy) and copolymers with styrene
Solid‐state photochemical generation of polymeric polyradicals: Poly(4‐vinylphenoxy) and copolymers with styrene
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聚合多自由基的固态光化学生成：聚（4-乙烯基苯氧基）和苯乙烯共聚物
DOI：
10.1002/pola.1992.080300711
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发表时间：
1992
期刊：
影响因子：
--
通讯作者：
P. M. Lahti
中科院分区：
文献类型：
--
作者：
F. Rossitto;P. M. Lahti
合成了聚（4′-乙烯基-2，4，6-三叔丁基二苯草酸酯）及其与苯乙烯的65：35和19：81共聚物。刚性相宽带光解的均聚物与石英过滤氙弧在77 K的结果在生产高达25%的理论自旋数/摩尔预期的定量生产侧苯氧基自由基，并显示没有重大损失的自由基信号在ESR温度低于100 K。纯光解均聚物1的ESR自由基信号强度的温度依赖性的居里定律分析示出了与低温下自由基自旋的反铁磁配对一致的曲率。由于通过键共轭的自由基自旋是不可能的，在这个系统中，反铁磁相互作用被解释在链内和/或链间通过空间交换相互作用。
Synthesis of poly(4′-vinyl-2,4,6-tri-tert-butyl-diphenyloxalate) and its 65 : 35 and 19 : 81 copolymers with styrene are described. Rigid phase broad-band photolysis of the homopolymer with a quartz filtered xenon arc at 77 K results in production of up to 25% of the theoretical number of spins/mol expected for quantitative production of pendant phenoxyl radicals, and shows no major loss of radical signal in the ESR at temperatures below 100 K. Curie law analysis of the temperature dependence of the ESR radical signal intensity for the neat photolyzed homopolymer 1 shows curvature consistent with antiferromagnetic pairing of radical spins at low temperatures. Since through-bond conjugation of radical spins is not possible in this system, the antiferromagnetic interaction is interpreted in terms of intrachain and/or interchain through-space exchange interactions.