棉织物的Mg(OH)_2晶体取向膜制备及性能

Preparation and performance of lamellar Mg(OH)_2 alignment film on cotton fabric

选用柠檬酸对棉织物进行表面改性,使之产生大量的—COOH基团,以吸附Mg(OH)2晶种;采用二次生长法,选择合适的生长条件,使Mg(OH)2晶种在棉织物表面二次生长,制得将棉织物表面完全包覆的Mg(OH)2晶体取向膜,并对生长在棉纤维表面的Mg(OH)2晶体的性能进行表征。从SEM图片可以清楚地看见,生成的Mg(OH)2晶体取向膜将棉织物表面完全包覆;垂直法织物阻燃性能和导热系数测试结果表明,Mg(OH)2晶体取向膜具有优良的热阻隔作用,可有效减缓外界气体进入和材料在热分解时挥发性产物逸出,提高了产品的阻燃效果。

The carboxylate groups are introduced onto cotton fabric by surface modification with citric acid in advance, which can help the Mg（ OH）2 seeds to be adsorbed onto the fabric. The Mg（ OH）2 seeds are prepared by the ammonia precipitation method with MgCI2 used as the Mg2＊ reactant and NH3. H2O as the precipitator, The secondary crystallizing of the lamella seeds onto the cotton fabric is achieved successfully using a secondary growing method by accurately controlling the reacting conditions of NH：H20 and MgCI2. The Mg（OH）2 crystals grown on the cotton fabric are characterized. The SEM analysis shows that the lamellar crystals are located on the surface of cotton fabric in a way like vertical fish scales. The vertical flamma- bility testing and thermal conductivity measurement indicate that lamellar Mg（OH）2 alignment film has good heat-insulating per- formance, which can reduce the entrance of fresh air and the release of volatile chemicals during heat decomposition. Thus the modified cotton fabric grown with lamellar Mg（OH）2 crystals features improved flame retardancy.