6-甲基-3-甲基丙烯酰氧乙基-3,4-2H-1,3-苯并噁嗪及其共聚物的合成

以6-甲基-3-羟乙基-3,4-2H-1,3-苯并噁嗪(MB-OH)和甲基丙烯酰氯为原料, 通过酯化反应合成了6-甲基-3-甲基丙烯酰氧乙基-3,4-2H-1,3-苯并噁嗪(MBEM). 采用自由基溶液聚合法, 以偶氮二异丁腈(AIBN)为引发剂, 以甲苯为溶剂, 以MBEM与N-苯基马来酰亚胺(NPMI)为单体, 合成了6-甲基-3-甲基丙烯酰氧乙基-3,4-2H-1,3-苯并噁嗪-co-N-苯基马来酰亚胺共聚物P(MBEM-co-NPMI)]. 分别对MB-OH, MBEM, P(MBEM-co-NPMI)进行加热固化, 得到相应的交联聚合物PMB-OH, PMBEM和PP(MBEM-co-NPMI)]. 对其结构、分子量和热性能进行了表征. 结果表明, PMB-OH, PMBEM, PP(MBEM-co-NPMI)]的最大损耗因子tanδ_max对应的玻璃化转变温度(T_g)分别为92, 129和181℃, 最大损耗模量G"_max对应的T_g分别为56, 91和156℃. 在N₂气氛围下, PMB-OH, PMBEM, PP(MBEM-co-NPMI)]失重5%的温度分别为257, 244和260℃; 失重10%的温度分别为280, 266和284℃; 800℃的残炭率分别为23.2%, 17.8%和14.0%. 表明PP(MBEM-co-NPMI)]具有优异的耐热性能.

Synthesis of 6-Methyl-3-methacryloxyethyl-3,4-dihydro-2H-benzo[e][1,3]oxazine and Its Copolymer

6-Methyl-3-methacryloxyethyl-3,4-dihydro-2H-benzoe]1,3]oxazine(MEBM) was synthesized by simple esterification reaction of 2-(6-methyl-4H-benzoe]1,3]oxazin-3-yl)-ethanol(MB-OH) with methacryloyl chloride. MBEM/N-Phenylmaleimide copolymerP(MBEM-co-NPMI)] was synthesized with N-phenylmaleimide(NPMI) and MBEM by free radical solution polymerization using azodiisobutyronitrile(AIBN) as initiator and toluene as solvent. The corresponding polymers of PMB-OH, PMBEM and PP(MBEM-co-NPMI)] were obtained by thermal cross-linking of MB-OH, MBEM and P(MBEM-co-NPMI), respectively. The molecular weight of the resulting copolymer was determined by gel permeation chromatography(GPC). The structure and chemical composition of MBEM and P(MBEM-co-NPMI) were characterized by Fourier transform infrared spectroscopy(FTIR) and nuclear magnetic resonance spectroscopy(1H NMR, 13C NMR). The curing behavior of all substances was also studied by differential scanning calorimetry(DSC) and FTIR. Thermal properties of the cross-linking polymers of PMB-OH, PMBEM and PP(MBEM-co-NPMI)] were investigated by dynamic mechanical analysis(DMA) and thermal gravime-tric analysis(TGA). The results show that the temperatures in maximum loss factor of the cross-linking polymers of PMB-OH, PMBEM, and PP(MBEM-co-NPMI)] are 92, 129, and 181℃, respectively. The temperatures in maximum loss modulus of the cross-linking polymers of PMB-OH, PMBEM and PP(MBEM-co-NPMI)] are 56, 91 and 156℃, respectively. Under N2, the temperatures of the cross-linking polymers of PMB-OH, PMBEM and PP(MBEM-co-NPMI)] at 5% mass loss are 257, 244 and 260℃, respectively, and the temperatures at 10% mass loss are 280, 266, 284℃, respectively. Their ultimate char yields are 23.2%, 17.8% and 14.0% at 800℃, respectively. These results suggest that PP(MBEM-co-NPMI)] has excellent heat resistant performance.