| 1. A novel bismaleimide-benzoxazine resin ( abbreviated as MI-BZ ) was synthesized by three steps. Firstly, N-p-hydroxylphenylmaleimide (MI) was prepared from maleic anhydride and p-aminophenol. Secondly, MI, 4, 4-2 amino diphenyl ether(ODA) and paraformaldehyde were used as raw materials to preparing MI-BZ with Mannich reaction; thirdly, a novel bismaleimide-benzoxazine resin was fabricated by a specific curing process. The chemical structure of MI and MI-BZ was characterized by FTIR, NMR. Section fracture surface of the resin was analyzed by SEM; The curing behavior of MI-BZ was characterized by DSC; two peaks appeared during its curing,that is about at 235 ? and 266?, respectively. TGA curves demonstrated that MI-BZ had excellent thermal stabilities under the condition of nitrogen, which began to decomposed until 410?, the 5% weight loss temperature is 438? and obtained 60.2%char yield at 800?.2. Firstly, carbic anhydride and p-aminophenol were used as raw materials to synthesising norbornene imide (NI). Secondly, a novel norbornene-imide functional benzoxazine (NI-BZ) was prepared based on NI, 4, 4-2 amino diphenyl ether (ODA)and paraformaldehyde via Mannich reaction. Lastly, a novel thermosetting resin was obtained with heatting curing. The structures of NI and NI-BZ have been characterized by FTIR, NMR. The curing kinetics of NI-BZ was monitored by DSC, and the thermal properties of poly (NI-BZ) have been evaluated using DMA and TGA, respectively. The results demonstrated that the thermal curing activation enerigy of NI-BZ was 86.27 kJ/mol and the reaction order was 0.91. Moreover, glass transition temperatures (Tg) of poly(NI-BZ) in the air was 215?. The temperature of loss 5% weight was 445? under a nitrogen atmosphere and obtained 63% char yield at 800?.3. A new class of polyether-urea-based benzoxazine (PUBZ) exhibits perfect toughness properties after thermal treatment has been developed, and which was synthesized via two steps. Firstly, amine-terminated polyether-based polyurea was synthesized using amine-terminated polyether and diphenyl methane diisocyanate (MDI) as raw materials. Secondly, PUBZ was prepared from amine-terminated polyether-based polyurea, bisphenol-A and paraformaldehyde through Mannich reaction. The structure of PUBZ has been confirmed by FTIR and NMR. The curing behavior was characterized by DSC.The effect of different length of polyether chains on the mechanical properties of PUBZ has been evaluated by dynamic mechanical analysis (DMA) in a tensile deformation. Thermal properties of PUBZ have been studied by DMA and thermogravimetric analysis (TGA). The conclusion demonstrated that if PUBZ had longer polyether chains that it has higher curing temperature and lower the glass transition temperature. Instead, it showed good thermal stability. When the molecular weight of amine-terminated polyether was 400 and D-400/PUBZ resin exhibited the highest toughness.4. Two containging-cyclopentana benzoxazine (abbreviated as TPBZ and TNBZ)were synthesized in this paper, and the raw material phenol (Ph) and nonylphenol (NP)were used to take the Mannich reaction with paraformaldehyde and methylcyclopentyl diamine (TAC), respectively. The chemical structure of TPBZ and TNBZ was characterized by FTIR and NMR. Then blending TPBZ and TNBZ with epoxy resin and curing, which were compared with the blend curing system of material TAC and epoxy resin. The blend characteristics of curing system were studied by DSC, and the thermal stability of which was analyzed by TGA. The result demonstrated that the thermal decomposition temperature of TPBZ/EP increased 32? than that of TAC/EP.The temperature of maximum weight loss rate increased 58?, and the carbon residue at 700? increased 11.2%,respectively. About TNBZ/EP, its thermal decomposition temperature increased 42?, and temperature of maximum weight loss rate increase 56?. |
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