Main-chain type polybenzoxazine precursors (MCPPs) are a current focus in the polybenzoxazine field for their improved char yield, thermal stability and film-forming ability compared to monomeric benzoxazines resins. To improve sustainability, there is an urgent need to utilize renewable feedstocks instead of fossil-based chemicals in the preparation of MCPPs. Here, renewable furfurylamine and salicylaldehyde were used as staring materials to synthesize high biomass content MCPPs through a three-steps polymerization route. The number-average molecular weight of a bio-based MCPP is 6100 g/mol, and it has a polydispersity index of 1.7. The furan-containing MCPP shows two polymerization stages during heating; the main exothermic stage at approximately 250 °C is attributed to the ring-opening polymerization of benzoxazine units, and the secondary stage at higher temperature is due to a crosslinking reaction between furan rings, forming furfurylamine Mannich bridges, and an oxidization-induced coupling reaction. The average activation energy of an MCPP is approximately 173.8 kJ/mol. The 240 °C-cured film is transparent with a glass transition temperature of over 300 °C. The crosslinked film shows a high thermal stability and a char yield of greater than 66% in a nitrogen atmosphere. Scanning electron microscopy (SEM) images indicated that a defect-free film can be made by controlling the curing parameters.

与单体苯并恶嗪树脂相比，主链型聚苯并恶嗪前体（MCPPs）是聚苯并恶嗪领域的当前焦点，因为它们具有更高的炭收率，热稳定性和成膜能力。为了提高可持续性，迫切需要在制备MCPP时利用可再生原料代替基于化石的化学品。在这里，可再生糠胺和水杨醛被用作起始原料，通过三步聚合路线合成高生物质含量的MCPP。生物基MCPP的数均分子量为6100g / mol，多分散指数为1.7。含呋喃的MCPP在加热过程中显示出两个聚合阶段。大约250°C时的主要放热阶段是由于苯并恶嗪单元的开环聚合，高温下的第二阶段是由于呋喃环之间的交联反应，形成糠胺曼尼希桥和氧化诱导的偶联反应。MCPP的平均活化能约为173.8 kJ / mol。240°C固化的薄膜是透明的，玻璃化转变温度超过300°C。该交联的膜在氮气氛下显示出高的热稳定性和炭产率大于66％。扫描电子显微镜（SEM）图像表明，可以通过控制固化参数来制备无缺陷的薄膜。240°C固化的薄膜是透明的，玻璃化转变温度超过300°C。该交联的膜在氮气氛下显示出高的热稳定性和炭产率大于66％。扫描电子显微镜（SEM）图像表明，可以通过控制固化参数来制备无缺陷的薄膜。240°C固化的薄膜是透明的，玻璃化转变温度超过300°C。该交联的膜在氮气氛下显示出高的热稳定性和炭产率大于66％。扫描电子显微镜（SEM）图像表明，可以通过控制固化参数来制备无缺陷的薄膜。