不同NaOH量对淀粉基木材胶粘剂结构性能的影响  

Effects of the amount of NaOH on structure and property of starch-based wood adhesives

作　　者：毛敏轩 竺梦龙 葛智益 于红卫[1] MAO Minxuan;ZHU Menglong;GE Zhiyi;YU Hongwei(National Engineering Technology Research Center for comprehensive utilization of wood resources,Zhejiang A&F University,Lin'an Zhejiang 311300,China)

机构地区：[1]国家木质资源综合利用工程技术研究中心,浙江农林大学化学与材料工程学院,浙江临安311300

出　　处：《工业安全与环保》2023年第3期95-98,共4页Industrial Safety and Environmental Protection

基　　金：十二五国家科技支撑计划项目(2012BAD24B03—3)。

摘　　要：以玉米淀粉和聚乙烯醇为原材料,通过质量分数30%的NaOH溶液处理后制成纯淀粉胶,并与异氰酸酯调制成淀粉基木材胶黏剂。研究了不同NaOH溶液用量对淀粉基木材胶黏剂结构和性能的影响,并通过FTIR、XRD、SEM、TG进行表征。结果表明:经过不同用量NaOH溶液处理过后的纯淀粉胶黏剂对比玉米淀粉并没有出现新的基团,但是羟基峰变尖变窄,它附近出现了明显的肩峰,当NaOH用量为淀粉质量的10%时,肩峰的宽度相对最大;XRD表明淀粉的内部结晶结构受到破坏,18°附近的峰强度明显增强;SEM图显示淀粉胶中淀粉表面受到碱的侵蚀,部分颗粒表面包裹聚乙烯醇膜,当NaOH用量为淀粉质量的10%时,淀粉胶中淀粉结晶结构破坏最明显,结晶度最低为50.5%;淀粉胶的耐热性随着碱量的增加先降低后增加,碱加入量为10%时,淀粉胶的初始热降解温度降低14.37%,淀粉基木材胶黏剂在此碱含量下胶合强度达到1.44 MPa。Starch-based wood adhesives were prepared using corn starch and polyvinyl alcohol(PVA)as materials through alkali and acid treatment,by adding pMDI with pure starch adhesive before applying to wood products.The effects of the amount of 30%NaOH on structural and property of starch-based wood adhesives were studied.To analyze the structure of pure adhesives used different characterization including the Flourier transform infrared spectroscopy(FTIR),the X-ray diffraction(XRD),the scanning electron spectroscopy(SEM).FTIR results showed that no more new group was showed in the pure starch adhesive comparing starch,the peak of hydroxyl group became narrow and sharp,shoulder peaks were obviously observed and the width of shoulder was largest when the amount of NaOH was 10%.XRD results suggested that crystalline structure of starch was destroyed,the peak intensity increased at 2=18°obviously.SEM showed that some corrosive damage was observed on the surface of starch and some starches were covered PVA films on surface.As the amount of NaOH was 10%,the crystalline structure of pure starch adhesive was damaged most obviously,and the crystallinity of pure starch adhesive was the lowest(50.5%);The heat resistance of starch adhesive decreased at first and then increased with the increase of Alkali content.When the Alkali content was 10%,the initial thermal degradation temperature of starch adhesive decreased by 14.37%,the bond strength of starch-based wood adhesives reached the highest value(1.44 MPa).

关 键 词：淀粉 胶黏剂 NAOH 结晶结构 胶合强度 

分 类 号：TQ432.2[化学工程]