摘要
以正硅酸乙酯、聚乙二醇、乙醇和氨水为主要原料,采用溶胶-凝胶法制备了固定化酶用的块状多孔SiO2。研究了引入不同聚乙二醇对多孔材料的结构、孔径分布和水热稳定性的影响。结果表明:随着聚乙二醇含量的增加和聚乙二醇相对分子量降低,胶凝时间缩短。随聚乙二醇引入量增加,材料的比表面积、孔容和平均孔径值均增加。当添加的聚乙二醇的质量分数为30%时,各值达到极大。添加不同含量聚乙二醇所得的多孔块材在80℃热水中浸泡72h后气孔率变化均不超过8%,质量损失率小于6%,热水浸泡前后材料的孔径分布曲线形状基本不变,所得多孔材料的水热稳定性能好。
Porous SiO2 blocks used as an enzyme carrier were synthesized by polymerization of tetraethyoxysilane （TEOS） in the presence of polyethylene glycol （PEG） via a sol- gel route. Materials made by different PEG concentrations were studied to determine their structure, pore distribution and durability in hot water. The results show that the gelling time of the hybrid gels decreases as the PEG content increases and the relative molecular weight of PEG decreases. The specific surface area, pore volume and average pore diameter of the obtained materials increase with increasing of PEG content, and reach the maximum values when the mass fraction of added PEG is 30 %. The change of porosity of the porous blocks made by different PEG contents after immersion in water at 80 C for 72 h is less than 8% and mass loss is less than 6%, However, the pore distribution curves of the blocks before and after such immersion are less changed. Thus, the synthesized materials possess good durability in hot water.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2005年第8期975-979,共5页
Journal of The Chinese Ceramic Society
