摘要
以改性碱木质素与聚乙烯醇(PVA)为原料,甲醛为交联剂,采用无机发泡原理,制备了聚乙烯醇/碱木质素发泡材料(PLFM)、聚乙烯醇/环氧化碱木质素发泡材料(PELFM)和聚乙烯醇/羟甲基化碱木质素发泡材料(PHLFM),并利用红外光谱、扫描电镜、DSC及TG对发泡材料进行了测定及分析。结果表明,PVA用量为5 g时,环氧化碱木质素用量为50%(以PVA质量计,下同),甲醛用量24%,硫酸用量54%,固化温度120℃制备的PELFM拉伸强度最大,为17.26 MPa。FT-IR分析显示,PLFM和PHLFM的苯环5位均发生取代,而PELFM没有发生取代;SEM图片显示发泡材料的孔径不规则,孔隙率较大;与另两种发泡材料相比,PELFM拉伸性能低,表观密度较低,吸水倍率也较低。从DSC和TG分析可知,3种发泡材料中PELFM具有较低的玻璃态转变温度,但其生物相容性最好,PELFM失重率最高峰对应的峰值温度最大且介于碱木质素与PVA之间,烧失后残余量也最大,表明PELFM的耐热性更好,热稳定性更强。
By using inorganic foaming principles,polyvinyl alcohol/alkali lignin foaming material（PLFM）,polyvinyl alcohol/epoxided alkali lignin foaming material （ PELFM ） , and polyvinyl alcohol/hydroxymethylated alkali lignin foaming material （ PHLFM ） , were prepared,with polyvinyl alcohol and modified alkali lignin as raw materials and formaldehyde as crosslinking agent. Then they were determined and analyzed by FT-IR,scanning electron microscope,DSC,and TG. The results showed that when PVA was 5g and the addition of epoxided alkali lignin was 50% of the PVA’ s mass,formaldehyde 24%,sulfuric acid 54%,and 120℃ for solidification, the obtained PELFM had the maximum tensile strength,17. 26 MPa. FT-IR results showed that substitutions were occurred on the benzene rings of PLFM and PHLFM at the 5-position,but PELFM not. SEM maps showed that the pore sizes were irregular and the porosity was large. Compared with others, PELFM possessed lower tensile property, apparent density, and water absorbency. From DSC and TG analysis,PELFM had the lowest glass transition temperature,the best biological compatibility,the maximum residual quantity and the maximum temperature corresponding to the highest lose rate peak. This temperature which was between the relevant temperatures of alkali lignin and PVA. It indicated that PELFM had the best heat resistance and thermal stability.
出处
《生物质化学工程》
CAS
北大核心
2015年第2期1-6,共6页
Biomass Chemical Engineering
基金
"十二五"国家科技支撑计划资助(2012BAD24B0403)
东北林业大学学生科研训练项目(KY2014018)
关键词
改性碱木质素
聚乙烯醇
发泡材料
modified alkali lignin
polyvinyl alcohol
foaming material
