Abstract

Hot-press compression molding was used to resinify a renewable source-derived linear 1,4-linked β-D-glucan copolymer, i.e., konjac glucomannan (KGM), via the generation of reactive aldehyde groups that tend to crosslink with hydroxyl groups of the glucans. The optimal molding temperature was found to be around 170 °C, with keeping the pressure at 20 MPa for 3.5 min and controlling the water content of the starting KGM powder to be around 22%. The molded KGM resin sheets were found to be crystallized in the annealed KGM polymorph form. Dynamic mechanical analysis revealed that the softening initiation temperature of the KGM resin was ca. 100 °C due to an onset of an increase in the loss modulus, E’’. The representative KGM resin sheets obtained under the optimal molding conditions were transparent, colored brown, and exhibited a tensile strength of 20.8 ± 4.5 MPa, Young’s modulus of 2.2 ± 0.3 GPa and elongation at break of 1.1 ± 0.2%.

摘要

热压模压成型用于树脂化可再生资源衍生的线性 1,4-连接 β-D-葡聚糖共聚物，即魔芋葡甘露聚糖 (KGM)，通过生成倾向于与羟基交联的反应性醛基葡聚糖。发现最佳成型温度约为 170 °C，压力保持在 20 MPa 3.5 分钟，并将起始 KGM 粉末的含水量控制在 22% 左右。发现模塑的 KGM 树脂片以退火的 KGM 多晶型物形式结晶。动态力学分析表明，KGM 树脂的软化起始温度约为 100 °C 由于损耗模量 E'' 开始增加。在最佳成型条件下获得的代表性 KGM 树脂片为透明、棕色、