季铵盐型阳离子瓜尔胶的制备

Preparation of quaternary ammonium type cationic guar gum

以瓜尔胶为原料,3-氯-2-羟丙基三甲基氯化铵为醚化剂,氢氧化钠为催化剂,乙醇为溶剂,制备了季铵盐型阳离子瓜尔胶,考察了乙醇浓度、醚化剂用量、pH值、反应温度、反应时间对季铵盐型阳离子瓜尔胶取代度和反应效率的影响,得出较佳制备条件为:乙醇质量分数为85%,pH11.0,反应温度70℃,反应时间4h,在较佳条件和醚化剂与瓜尔胶质量比为7∶100的条件下,阳离子瓜尔胶取代度为0.1651,反应效率86.79%.

The quaternary ammonium type cationic guar gum als, 3-chloro-2- （ hydroxypropyl ） trimethylammonium chloride was prepared by using as cationic etherifying guar gum as raw materiagent, sodium hydroxide as catalyst, and ethanol as solvent. The effects of some factors such as ethanol concentration, amount of etherifying agent, pH, reaction temperature and reaction time on substitution degree and reaction efficiency of quaternary ammonium type cationic guar gum were discussed, and better reaction conditions were determined. These conditions are ethanol concentration of 85%, pH pf 11.0, reaction temperature at 70 ℃, and reaction time for 4 h. The substitution degree and reaction efficiency of cationic guar gum are 0. 1651 and 86. 79% respectively under these conditions when the mass ratio of etherifying agent to guar gum is 0. 07.