新型CO_2硬化动物胶粘结剂改性工艺的优化

针对动物胶粘结剂砂型强度低、易于溃散的问题,通过碱解、改性处理得到了一种新型动物胶粘结剂,并采用吹CO_2气体的方式将其硬化.选择并优化动物胶粘结剂的碱解工艺,引入活性基团对动物胶粘结剂进行酯化反应和接枝共聚改性,从而进一步提高其粘结强度,并对新型动物胶粘结剂的吹气硬化和改性机理进行了理论分析.结果表明,动物胶粘结剂的最佳质量配比为丙烯酸∶过硫酸铵∶葡萄糖∶动物胶=30∶3∶15∶100.当改性温度为75℃、改性时间为90 min时,型砂的抗压强度可以达到2.75 MPa,满足快速制芯生产的要求.

Optimization for modification technology of novel CO2 hardened animal glue binder

In order to solve the problem that the animal glue binder core mould has low strength and is easy to collapse, a novel animal glue binder was prepared through alkaline decomposition and modification treatment, and the animal glue binder was hardened with blowing CO₂ gas. The alkaline decomposition technology of animal glue was selected and optimized, and the active groups were introduced to perform the esterification reaction and grafting copolymerization modification for animal glue. Therefore, the bonding strength of animal glue binder could be further improved. In addition, the gas hardening and modification mechanisms of novel animal glue binder were theoretically analyzed. The results show that the optimum mass ratio of animal glue binder is 30(acroleic acid)∶3(ammonium peroxydisulfate)∶15(glucose)∶100(animal glue). When the modification temperature is 75 ℃ and the modification time is 90 min, the compressive strength of mould sand is 2.75 MPa, which can meet the requirement of rapid core-making production.