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通过酸碱处理和机械研磨结合的方法制备纳米纤维素(CNFs),并利用冻融循环法分别制备了聚乙烯醇(PVA)和纳米纤维素/聚乙烯醇(CNFs/PVA)复合水凝胶,以及聚乙二醇(PEG)改性PVA和CNFs/PVA复合水凝胶。考察不同配方下复合水凝胶的微观形貌变化,并对复合水凝胶的溶胀性能、压缩强度及热稳定性能进行研究。结果表明,CNFs与PEG对PVA水凝胶的微观形貌均有改善作用,加入PEG后形成的PEG/PVA凝胶产生明显的三维网络结构。当PEG与CNFs同时加入到PVA凝胶后形成的CNFs-PEG/PVA凝胶具有均匀的互穿孔洞结构,此时复合水凝胶的孔隙率最高((67.5±4.3)%),溶胀度最好(980%),且压缩强度较PVA水凝胶也有所提升。PEG对复合凝胶的热稳定性无影响,而加入CNFs后,CNFs-PEG/PVA复合凝胶的初始热分解温度从235℃上升至300℃,显著提高了PVA凝胶的热稳定性。
Nanofibers (CNFs) were prepared by a combination of acid-base treatment and mechanical grinding, and polyvinyl alcohol (PVA) and nanofibers / polyvinyl alcohol (CNFs / PVA) composite hydrogels were prepared by freeze- , And polyethylene glycol (PEG) modified PVA and CNFs / PVA composite hydrogel. The morphologies of the composite hydrogels under different formulations were investigated. The swelling properties, compressive strength and thermal stability of the composite hydrogels were investigated. The results showed that both CNFs and PEG could improve the microstructure of PVA hydrogel, and the PEG / PVA gel formed after addition of PEG produced obvious three-dimensional network structure. The CNFs-PEG / PVA gel formed by the simultaneous addition of PEG and CNFs to PVA gel has a uniform interpenetrating pore structure, and the porosity of the composite hydrogel is the highest (67.5 ± 4.3)%). The degree of swelling Good (980%), and compressive strength than PVA hydrogel has also been improved. PEG did not affect the thermal stability of the composite gel. However, the initial thermal decomposition temperature of CNFs-PEG / PVA composite gel increased from 235 ℃ to 300 ℃ after adding CNFs, which significantly improved the thermal stability of the PVA gel.