氯乙酸改性魔芋葡甘聚糖制备混凝土脱模剂的研究

Preparation of concrete release agent by chloroacetic acid modified konjac glucomannan

采用氯乙酸对魔芋葡甘聚糖(KGM)进行改性制备魔芋葡甘聚糖水溶胶,研究了不同工艺条件对改性产品黏度的影响。采用FT-IR、TG等对改性产品的结构和性能进行分析表征。结果表明,最佳改性工艺条件为:m(KGM)∶m(氯乙酸)=1∶(0.8～0.9),反应温度60℃,pH值为8～9,溶解时间为3 h的条件下,所得溶胶黏度为23～25 s,该黏度符合混凝土脱模剂的要求;改性后水溶胶的成膜性能、抗菌性能等均有明显提高。红外光谱分析和热分析显示,改性后KGM发生了醚化反应,引入了羟甲基,热稳定性好,满足混凝土脱模剂使用极限温度的要求。经检测该产品性能符合JC/T 949—2005《混凝土制品用脱模剂》的要求。

The hydrosol was prepared from chloroaeetate acid modified KGM,and the factors effect on the viscosity were studied. The material properties and structure were investigated by FT-IR and TG. It indicated that the optimum conditions were： the mass ratio of KGM and ehloroacetic acid was l：（0.8-0.9）,reaction temperature of 60 ℃,pH=8-9,dissolving time of 3 h,the film-forming properties and anti-bacterial properties of modified KGM hydrosol were increased significantly, an ideal viscosity 23 s to 25 s meeting concrete release agent requirements was obtained. Infrared spectroscopy and thermal analysis showed that etherification reaction occurred and hydroxyl methyl was introduced,and good thermal stability meeting the requirements of concrete release agent extreme using temperatures. The test results showed it can meet the requirements of JC/T 949-2005＂Concrete Mold Release Agents＂.