高温花生粕蛋白基胶黏剂的制备与表征

Preparation and Characterization of Hot-Pressed Peanut Meal Based Adhesive

【目的】以高温花生粕(HPM)为试验材料,通过复合改性交联制备胶合强度高、耐水性好的HPM蛋白基胶黏剂(HPMA),为HPMA的产业化应用提供技术和理论依据。【方法】采用十二烷基硫酸钠(SDS)、纳米SiO2(nSiO2)和聚酰胺多胺环氧氯丙烷(PAE)树脂复合改性交联制备HPMA,研究HPMA制备的杨木胶合板胶合强度以及HPMA外观、黏度、固体含量、pH、热稳定性、蛋白质二级结构和表面结构的变化。【结果】HPMA制备的杨木胶合板干态、温水湿态和沸水湿态胶合强度分别提高113%、114%和81%,达到国家Ⅰ类杨木胶合板标准。HPMA呈棕褐色,黏度、固体含量、pH分别为6448 mPa·s、31.33%和5.83,热分解温度高达317℃。HPMA制备过程中蛋白质二级结构和基团均发生显著变化,表面结构由粗糙无序变得紧致均一。【结论】HPMA胶合强度和耐水性显著提高的主要原因是SDS使蛋白质二、三级结构打开,疏水基团暴露,并与nSiO2和PAE发生超支化交联形成不溶水的三维网络结构。

【Objective】Hot-pressed peanut meal(HPM)was used as the research object to prepare HPM adhesive(HPMA)with high bonding strength and good water resistance by composite modified cross-linking,which would expected to provide technical and theoretical basis for its industrial application in the wood field.【Method】HPM was modified and crosslinked by sodium dodecyl sulfate(SDS),nano-SiO2(nSiO2)and polyamide polyamine epichlorohydrin(PAE)resin to study the bonding strength of poplar plywood prepared by HPMA in modified cross-linking process.The appearance,viscosity,solid content,pH,thermal stability,protein secondary structure and surface structure of HPMA in the modified cross-linking process were evaluated.【Result】The results showed that the dry,warm and boiling water wet bonding strengths of poplar plywood prepared by HPMA increased by 113%,114%and 81%,respectively,and reached the national class I poplar plywood standard.The prepared HPMA was brown,and the viscosity,solid content and pH were 6448 mPa·s,31.33%and 5.83,respectively.The thermal decomposition temperature of HPMA was as high as 317℃.The secondary structure and groups of proteins changed significantly during the preparation of HPMA,and the microscopic surface structure was tight from coarse.【Conclusion】The main reason for the improvement of bonding strength and water resistance was that the secondary and tertiary structure of protein were opened by SDS,exposing the hydrophobic groups,and hyperbranching with nSiO2 and PAE to form a three-dimensional network structure of insoluble water.It might provide technical and theoretical bases for the industrial application of HPMA.