戊二醛改性提高大豆胶粘剂耐水性能

以脱脂大豆粉(SF)为原料,选用十二烷基硫酸钠(SDS)和戊二醛(GA)作为改性试剂,制备出具有较好耐水性能的木材用胶粘剂,并应用于杨木胶合板,分别研究了pH值、戊二醛用量、反应时间以及最终改性胶粘剂贮存时间对耐水胶合性能及表观粘度的影响,并采用十二烷基硫酸钠.聚丙烯酰胺凝胶电泳(SDS-PAGE)和傅屯叶变换红外光谱(FT-IR)分析手段探讨了改性胶粘剂耐水性能增强机理.结果表明:较佳合成工艺为:pH值为12.0,GA添加量0.80wt%(基于脱脂豆粉质量),反应时间1.0 h,反应温度30.0℃.按照GB/T 9846-2004胶合板中Ⅱ类板标准检测,耐水胶合强度可达0.68MPa.SDS-PAGE谱图说明蛋白质分子间形成化学键交联,FT-IR分析表明有环状吡啶结构生成,这些可能是改性胶粘剂耐水性能提高的原因.

Improve the Water Resistance of Soy-based Adhesive by using Glutaraldehyde

An investigation was conducted to improve the water resistance of soy flour(SF)-based wood adhesive by using sodium dodecyl sulfate(SDS)and glutaraldehyde(GA) ,and the resulted soy glue was applied to poplar plywood. The effects of pH,GA dosage,reaction time and storage time on water resistance and apparent viscosity were studied in the paper. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis ( SDS-PAGE) and Fourier transform infrared spectrometry ( FT-1R) were used to analyze the mechanism of bonding strength reinforcing. Results indicated that optimal synthesis parameters were:pH12.0,GA usage 0.80wt% (based on the mass of defatted soy flour) ,reaction lime 1.0 h and reaction temperature 30.0℃ , respectively. Adhesive strength was improved up to 0. 68 MPa after water treatment at 63℃ for 3. 0 hours according to GB/T 9846-2004 Plywood. It is presumed that crosslinkage can be formed based on SDS-PAGE analysis and pyridine ring was observed from FT-IR spectra. These may explain why such adhesive existed better resistant to water.