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讨论了在氧存在下辐照乙烯类单体形成的过氧化物在引发聚合及共聚合中的行为及辐照温度对形成过氧化物的速率和性质的影响.主要结果如下:(1)过氧化物的生成及其引发聚合皆按自由基机制进行.V_0∝c~(1/2),G_R=10;(2)过氧化物的生成活化能为:E_(f(MMA)=11,E_f(Sr)=9.6,E_(f(AN))=8.5kcal/mol.聚合过程中的表观活化能E_MMA=11.4,E_(▽A)=11.4kcal/mol.引发活化能E_i(MMA)=E_i_(▽A)=13kcal/mol;(3)过氧化物生成速率随辐照温度的升高而增加,高温辐照的过氧化物的引发性质发生变化;(4)辐照形成的过氧化物在聚合条件下的分解速率较BPO的分解速率缓慢而平稳,保证了聚合进程的平稳性;(5)预辐照一种单体可以引发另一种未辐照单体共聚.预辐照不同单体在共聚中的引发能力主要取决于预辐照单体的化学结构.
The effects of peroxide on the polymerization and copolymerization induced by the irradiation of vinyl monomers in the presence of oxygen and the effect of irradiation temperature on the formation rate and the properties of peroxide were discussed. The main results are as follows: (1) The formation of oxides and the initiation of polymerization are all based on the free radical mechanism. V 0αc 1/2, G_R 10; (2) The activation energy of formation of peroxide is: E f MMA = 11, E_f Sr = 9.6, E_f AN = 8.5kcal / mol. The apparent activation energies E_MMA = 11.4 and E_ (▽ A) = 11.4 kcal / mol during polymerization.The activation energy E_i (MMA) = E_i_ (▽ A) = 13 kcal / mol. (3) The rate of peroxide formation increased with the increase of irradiation temperature, and the priming property of peroxide irradiated by high temperature changed. (4) The rate of decomposition of the oxide under polymerization conditions is slower and more stable than that of BPO, ensuring the stability of the polymerization process. (5) Pre-irradiation of one monomer can lead to copolymerization of another non-irradiated monomer Pre- According to the different monomers in the initiator of the copolymerization mainly depends on the chemical structure of pre-irradiation monomer.