半干法制备两性瓜尔胶的结构及其增强性能的研究

采用半干法工艺在同一反应器内合成了粉状两性瓜尔胶,用红外光谱(FT-IR)、扫描电镜(SEM)对产物进行了结构表征。通过浆内添加研究了两性瓜尔胶的取代度、用量和浆料pH值对纸张增强性能的影响,并与非离子瓜尔胶和阳离子淀粉的增强性能进行了对比。结果表明,合成样品阳离子取代度(DSc)大于0.25,阴离子取代度(DSa)为0.05～0.10;改性剂与瓜尔胶在颗粒表面与内部都发生反应;制备的两性瓜尔胶对纸张有较好的增强效果,尤其是中碱性条件下效果显著;当两性瓜尔胶添加量为0.3%时,针叶木CTMP浆的裂断长、耐折度、耐破指数和撕裂指数分别提高了13.3%、70%、17.5%和10.1%。

Structural Properties of Amphoteric Guar Gum and Its Application as Strength Aids

The amphoteric guar gum was synthesized by half-dry process, and its structure properties were characterized and analyzed by FT-IR and SEM. The effects of substitution degree of the amphoteric guar gum, dosage of the amphoteric guar and pH value of the pulp on the paper strengthening effect were studied, and the nonionic guar gum, cationic starch were used for comparison. The results showed that the synthetic products' cationic degree of substitution was over 0.25, and anionic degree of substitution was abo...