酸碱对改性豆胶耐水胶合强度的影响

采用酸、碱和酸碱联合3种方式处理脱脂豆粉,制备改性豆胶,并用于压制三层胶合板,以Ⅱ类胶合板的标准检测其耐水胶合强度。结果表明,酸碱处理均能提高改性豆胶的耐水性能,当酸用量为11.9份时,改性豆胶压制的胶合板最高耐水胶合强度为0.48MPa;碱的用量为22.6份时,耐水胶合强度为0.43MPa;酸碱联合改性豆胶的效果优于单独用酸或碱改性,当酸、碱的用量分别为11.9和39.9份时,改性豆胶压制的胶合板最优耐水胶合强度为0.61MPa。红外光谱分析表明,酸碱联合改性豆胶能综合酸、碱单独使大豆蛋白变性的优点,更有利于提高改性豆胶的耐水性。

Influence of acid and base on modified soy-based adhesive's water-resistant bonding strength

The defatted soy flour was processed by acid,base and acid-base to preparing modified soy-based adhesives,which were used on pressing three layers plywood,and its water-resistant bonding strength was tested by the request of China National Standard Plywood type Ⅱ.The results illuminated that the water-resistant of modified soy-based adhesives improved by acid or base' s processing.When the usage of acid was 11.9,the higher water-resistant bonding strength of plywood which pressed with modified soy-based adhesive was 0.48 MPa;and the usage of base was 22.6,the water-resistant bonding strength was 0.43 MPa.The acid-base as soy-based adhesives' modifier better than single acid or base,when the usage of acid and base were 11.9 and 39.9,the best water-resistant bonding strength of plywood was 0.61 MPa.The infrared spectrum analysis showed that as the modifiers of soy-based adhesives acid-base gather the merit of single acid or base modifying soy proteins,and improving the water-resistant of modified soy-based adhesive more effectively.