交联羧甲基化水葫芦纤维研制及其吸水与保水性能考察

以水葫芦纤维为原料,在乙醇、KOH碱性溶液中,以氯乙酸为醚化剂,制备了羧甲基化水葫芦纤维.并用FeCl3作交联剂,制得交联羧甲基化水葫芦纤维基吸水剂.通过FT-IR,SEM进行化学和表面结构表征、通过滴定法测定羧甲基纤维素的含量、通过称量法测定水葫芦基吸水剂在蒸馏水和典型的化肥液中的吸水率.考察了KOH、氯乙酸、交联剂用量以及反应温度对吸水率的影响,并进一步考察了水葫芦基吸水剂对土壤的保水性能.结果表明:水葫芦纤维、氯乙酸及KOH的适宜质量比为1∶1.25∶1.05;在60 ℃醚化2.0 h,接着在22℃用0.45 ％(wt)的FeCl3(相对羧甲基化水葫芦纤维)交联,所得交联羧甲基化水葫芦纤维基吸水剂在蒸馏水中的吸水率可达78 mL·g-1,在弱电解质(尿素)溶液中的吸水率略有下降、而在强电解质(氯化钾和碳酸铵)溶液中的吸水率明显下降;含5％交联羧甲基化水葫芦纤维基吸水剂的泥土,其保水率明显提高.

Preparation of Crosslinked Carboxymethyl Cellulose Derived from Water Hyacinth and its Performance of Water Absorption and Retention

The water hyacinth-based water absorbent was prepared by converting the water hyacinth cellulose into carboxymethyl cellulose by using chloroacetic acid as etherification agent in the presence of ethanol and KOH,and then the formed carboxymethyl cellulose was crosslinked by using FeCl3 as the crosslinking agent.The chemical and surface structures of the prepared water hyacinth-based absorbent were characterized by FT-IR and SEM,respectively.In distilled water and in several typical fertilizer solutions,the water absorbencies of the prepared water hyacinth-based absorbent were determined by filtration and weighing.The content of the carboxymethyl cellulose was measured by titration.The effects of KOH,chloroacetic acid,crosslinking agent and reaction temperature on water absorbency of the prepared water hyacinth-based absorbent were investigated.The results show that the suitable mass ratio of water hyacinth cellulose,chloroacetic acid and KOH is 1︰1.25︰1.05.Under following preparation conditions: etherification at 60℃ for 2.0 h and crosslink with 0.45%(wt) FeCl3 at 22℃,the water absorbency of the prepared water hyacinth-based absorbent in distill water reaches 78 mL·g-1;and in the weak electrolyte(urea),its water absorbency drops slightly,while in the strong electrolyte(potassium chloride or ammonium carbonate),it drops obviously.For the soil containing 5% water hyacinth-based absorbent,the water retention value can be enhanced obviously.