低温脱脂豆粕增强棉籽粕胶黏剂制备与性能

Preparation and property of cottonseed meal adhesive reinforced by low-temperature defatted soybean meal

【目的】阐明不同豆粕添加量对改性棉籽粕胶黏剂耐水胶合强度和黏度的影响机理,为蛋白基胶黏剂的工业化生产与应用提供依据。【方法】以高温脱酚棉籽粕、低温脱脂豆粕和交联剂三缩水甘油胺为原料,在控制豆粕添加量与原料配比的基础上,合成豆粕改性棉籽粕胶黏剂,并制备杨木胶合板。采用旋转流变仪测试胶黏剂黏度;采用傅里叶变换红外光谱仪、X射线晶体衍射仪和扫描电子显微镜表征胶黏剂的结构和形貌;采用热重分析仪和万能力学拉伸实验机分析胶黏剂的热稳定性和胶接力学性能;最后,综合解析改性胶黏剂的胶接增强机理。【结果】随着豆粕添加量的提高,体系中赖氨酸数量增多,提供了更多的交联反应活性位点,形成多重交联网络结构的机械互锁作用,提高了胶黏剂的耐水胶接性能和黏度。当豆粕添加量为10%时,胶黏剂TCM/SM10的干状和耐水胶合强度分别为1.24和0.79 MPa。提高豆粕添加量至30%时,胶黏剂的干状和耐水胶合强度相比TCM分别提高了60.4%和27.8%,达1.54和0.92 MPa,胶黏剂黏度提高至20.689 Pa·s,且热稳定性、韧性均有所改善。【结论】采用低温豆粕部分替代棉籽粕交联改性制备棉籽粕胶黏剂,有效提高了胶黏剂的涂布性能和耐水胶接性能。为生产低成本高性能的改性棉籽粕胶黏剂提供新的思路,有助于推动蛋白基胶黏剂的规模化工业应用。

[Objective] The influence mechanism of different soybean meal additions on the water-resistant bond strength and viscosity of modified cottonseed meal-based adhesive was clarified,which provided basis for industrial production and application of protein-based adhesive.[Method] High-temperature dephenolized cottonseed meal,low-temperature defatted soybean meal and triglycidylamine were raw materials.The cottonseed meal adhesive modified by soybean meal was synthesized by controlling the addition amount of soybean meal and the ratio of raw materials.Then,poplar plywoods were prepared.The viscosity of the adhesive was measured by rotary rheometer.The structure and morphology of the adhesive were characterized by Fourier transform infrared spectrometer,X-ray crystal diffractometer and scanning electron microscope.Thermogravimetric analyzer and universal mechanical tensile tester were used to analyze the thermal stability and bond mechanical properties of the adhesive.Finally,the mechanism of bond enhancement of the modified adhesive was comprehensively analyzed.[Result] With the increase of soybean meal content,the amount of lysine in the system increased,providing more active sites for crosslinking reaction,forming a mechanical interlocking effect of multiple crosslinking network structure,and improving the water-resistant bond performance and viscosity of the adhesive.When the addition of soybean meal was 10%,the dry strength and water-resistant bond strength of adhesive TCM/SM10 were 1.24 and0.79 MPa,respectively.Compared with TCM,when the addition of soybean meal increased to 30%,the dry bond strength and water-resistant bond strength of the adhesive increased by 60.4% and 27.8%,reaching1.54 and 0.92 MPa,respectively,and the viscosity of the adhesive increased to 20.689 Pa·s.The thermal stability and toughness were improved.[Conclusion] The use of low-temperature soybean meal as a partial substitute for cottonseed meal crosslinking modification to prepare cottonseed meal adhesive effectively improves the coating performance and water resistance of the adhesive,providing new ideas for the production of low-cost and high-performance protein based adhesives.It provides a new idea for producing modified cottonseed meal adhesive with low cost and high performance,and is helpful to promote the largescale industrial application of protein-based adhesive.