以邻位酰胺双酚、甲醛溶液及间氨基苯乙炔为原料,通过曼尼希反应成功地合成了一种新型乙炔基邻位酰胺双官能化苯并噁嗪单体(AI-ac),并经升温处理得到聚苯并噁嗪[poly(AI-ac)]及聚苯并噁唑(PBO-AI-ac)。采用核磁共振氢谱/碳谱和傅里叶变换红外光谱对该苯并噁嗪的化学结构进行了表征。采用差示扫描量热法和原位红外光谱对单体聚合进行了研究。采用热重分析和动态/静态机械分析分别研究了聚苯并噁嗪的热稳定性及相关力学特征。结果表明:AI-ac噁嗪单体具有较低的固化温度,且聚苯并噁嗪及聚苯并噁唑有着良好的热稳定性和优异的介电性能。两者在800℃氮气氛围中的残炭率分别高达65%和70%。
Benzoxazine is a kind of thermosetting resin developed rapidly in recent years.Compared with traditional resins,such as phenolic resin and epoxy resin,benzoxazine resin has good thermal stability,excellent flame retardancy,high mechanical strength and stable insulation.A new bisfunctional benzoxazine monomer,AI-ac,was synthesized by Mannich reaction using o-acetamide bisphenol,formaldehyde solution and m-aminobenzene acetylene as raw materials.Its polymerized products,both polybenzoxazine (poly(AI-ac)) and polybenzoxazole (PBO-AI-ac) were obtained by heating treatment.The chemical structure of benzoxazine was characterized by 1H and 13C NMR and fourier transform infrared (FT-IR) spectra.The polymerization of monomers was studied by differential scanning calorimetry (DSC) and in situ FT-IR.The thermal stability and mechanical properties of the thermosets were studied by thermogravimetric analysis (TGA),TMA and DMA.The results shown that AI-ac oxazine monomer had lower curing temperature.Moreover,poly(AI-ac) and PBO-AI-ac had good thermal stability and excellent dielectric properties.Carbon residue values of poly(AI-ac) and PBO-AI-ac in nitrogen atmosphere at 800℃ were 65% and 70%,respectively.
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