柱填充再生纤维素交联凝胶微球的制备及其力学性质的调控

Regenerated cellulose microspheres for packed column: fabricationand mechanical regulation

摘要:

以棉短绒纤维素为原料，采用乳化法（低表面活性剂用量）制备了纤维素凝胶微球。利用XRD、光学显微镜、粒径分析仪、SEM、材料力学测试仪等对纤维素凝胶微球的形貌、结构、力学性能进行了表征及测试。考察了乳化剂用量、转速、m（纤维素溶液）:m（液体石蜡）、溶液黏度以及交联剂用量等因素对纤维素凝胶微球平均粒径的影响。结果表明，在纤维素溶液（质量分数4%）为10g、交联剂用量为300 μL（交联度为3%）、乳化剂用量为0.1g、液体石蜡用量为30g、转速为200r/min，溶液黏度为2474Pa?s（增黏时间为15min）的条件下，能制备平均粒径为610 μm的纤维素凝胶微球。其中，粒径范围在400~800 μm的纤维素凝胶微球占比为54.93%。另外，用乙醇水溶液作为凝固浴来调节纤维素凝胶微球中纤维素链的聚集状态进而改变纤维素凝胶微球的力学性能。通过无水乙醇处理的纤维素凝胶微球能够承受60 mL/min流速产生的水压而不发生形变，表现出良好的力学性能，有望于应用于血液灌流等填充柱领域。

Abstract:

Employing cotton staple cellulose as raw material, cellulose microspheres were prepared by emulsification method (low surfactant dosage). XRD, optical microscope, particle size analyzer, SEM, material mechanics tester, etc. were used to characterize and test the morphology, structure and mechanical properties of cellulose microspheres. The effects of emulsifier dosage, speed, m (cellulose solution): m (liquid paraffin), solution viscosity and crosslinker dosage on cellulose microsphere size were investigated. The results showed that cellulose microspheres with an average particle size of 610 μm could be prepared under the conditions of cellulose solution (mass fraction 4%) of 10 g, crosslinker dosage of 300 μL (crosslinking degree of 3%), emulsifier dosage of 0.1 g, liquid paraffin dosage of 30 g, speed of 200 r/min, and solution viscosity of 2474 Pa?s (viscosity time of 15 min). Among them, cellulose microspheres with particle size range of 400~800 μm accounted for 54.93%. In addition, ethanol aqueous solution is used as a coagulation bath to adjust the aggregation state of cellulose chains in cellulose microspheres, thereby changing the mechanical properties of cellulose microspheres. Cellulose microspheres treated with absolute ethanol can withstand the water pressure generated by a flow rate of 60 mL/min, so that cellulose microspheres do not deform, showing good physical properties, and is expected to be used in filled column fields such as hemoperfusion.