NMMO溶剂法纤维素海绵的制备及性能研究——成孔剂用量的影响

以N-甲基吗啉-N-氧化物(NMMO)为溶剂、以棉浆粕为原料、以无水硫酸钠为成孔剂制备了纤维素海绵,探讨了成孔剂用量对纤维素海绵形态结构、孔隙率、吸水性、保湿性和拉伸强度的影响。结果表明,随着成孔剂用量的提高,所制得的纤维素海绵平均孔径变大,孔壁变薄,通孔增多,但成孔剂用量过多时,海绵孔壁会产生轻微断裂。此外,随着成孔剂用量的提高,海绵的孔隙率及吸水保湿性提高,拉伸强度则有所下降,综合考虑海绵的性能及成型过程的难易程度等因素,当成孔剂用量为纤维素溶液的3倍为宜,所得纤维素海绵的孔隙结构均匀饱满、综合性能较高。

Study on preparation and properties of cellulose sponges by using NMMO as solvent Effect of amount of pore-forming agent

Cellulose sponges were prepared by using N-methylmorpholine-N-oxide （NMMO） as the solvent, cotton pulp as raw material and anhydrous sodium sulfate as the pore-forming agent. The effect of the amount of pore-forming agent on the morphological structure, porosity, water absorption, moisture retention capacity and tensile strength of cellulose sponge were investigated. The results showed that with the increase of the amount of the pore-forming agent, cellulose sponge exhibited larger average pore size, thinner walls of the pore and more open- pore structure. However, a slight fracture could be observed in the walls of the pore structure of sponge with the excess amount of pore-forming agent. In addition, with the increasing amount of the pore-forming agent, the porosity, water absorption and moisture retention capacity of sponge were increased while the tensile strength was decreased. By comprehensively considering the properties of cellulose sponge and the difficulty of forming process, the amount of pore-forming agent was selected to be three times the mass of cellulose/NMMO · H2O solution, and the cellulose sponge showed higher comprehensive performance with more homogeneous and completed pore structure.