Synthesis and properties of benzoxazine with maleimide functional group, polybenzoxazine resin curing study

• Main Authors: Juin-Meng Yu, 游俊盟
• Other Authors: Ying-Lin Liu
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/tc4h8q

碩士 === 中原大學 === 化學工程研究所 === 93 === Abstract In this study, a maleimide-containing benzoxazine monomer, 3-phenyl-3-4-dihydro-2H-6-(N-maleimido)-1,3-benzoxazine (HPM-Ba), was prepared with using N-(4-hydroxyphenyl)maleimide, formaldehyde, and aniline as starting materials. The chemical structure of HPM-Ba was confirmed by FT-IR, 1H-NMR, and Elemental Analysis measurements. A two-stage thermal polymerization was observed with HPM-Ba under heat, in which the first stage was the reaction of maleimide groups and the second one was the ring-opening reaction of benzoxazine groups. The reaction scheme was demonstrated with differential scanning calorimetry (DSC) and thermal-stage FT-IR observation. The completely cured P-HPM-Ba-Ⅱ polymer exhibited a high glass-transition temperature of 204℃, good thermal stability about 330,℃and self-extinguishing behavior . In addition, cured polymers were also obtained from the blends of 3,4-dihydro-3-phenyl-2H-1,3-benzoxazine（PPA）and various maleimide compounds. The effect of pendent groups of maleimide derivates on the polymerization scheme of the monomer blends were studied by DSC. The ring-opening polymerization of benzoxazine groups was catalyzed by the acidic –OH and –COOH groups in maleimides. The catalytic effects were directly observed with DSC measurements and the reaction scheme was confirmed with TGA-GC/MS measurements on the evolved gases in degradation. Meanwhile, the polymerization maleimide group was also catalyzed with benzoxazine groups. These catalytic effects shifted the polymerization of the monomer blends toward low temperatures. Therefore, polymers from PPA and P-cpm (maleimide with carboxylic acid group) showed the lowest polymerization temperature and the highest glass-transition temperature（224 ℃）among the cured polymers. It was concluded that combination of maleimide and benzoxazine resulted in high performance thermosets, both in processing and properties.