中文摘要：

采用微生物发泡法，将酵母菌作为微生物发泡剂，结合循环冷冻–解冻法制备聚乙烯醇(PVAL)／羧甲基纤维素(CMC)多孔复合材料。通过单因素试验探讨了酵母菌与葡萄糖比例(Y／G)、发泡时间、发泡温度和CMC与PVAL比例(CMC／PVAL)对发泡效果的影响，采用L9(34)正交试验进一步优化了发泡条件，通过傅立叶变换红外光谱和扫描电子显微镜(SEM)表征了PVAL／CMC多孔复合材料的结构。结果表明，当Y／G比例为2.8／1、发泡温度为31℃、发泡时间为60min、CMC／PVAL比例为0.7／1时，PVAL／CMC多孔复合材料发泡效果最佳，其中CMC／PVAL比例为主要影响因素，此外，Y／G比例对发泡效果的影响也较为显著。SEM照片显示，以酵母菌为发泡剂制备的PVAL／CMC多孔复合材料具有较高的孔隙率，大孔平均孔径在180μm左右，小孔平均孔径在15μm左右，呈现大孔套小孔的开孔结构。

英文摘要：

The polyvinyl alcohol(PVAL)/carboxymethylcellulose(CMC) porous composites were prepared by microbial foaming and cyclic freezing-thawing method. The yeast was mixed into PVAL/CMC composites as microbial foaming agent. The effects of Y/G proportion,foaming time,foaming temperature,and CMC/PVAL proportion on porous composites were discussed by single factor experiments. L9(34) orthogonal test was adopted to optimize the foaming condition. The structures of PVAL/CMC porous composites were characterized by FTIR and SEM. The results show that when the foaming time is 60 min at 31℃,the proportion of CMC/PVAL is 0.7/1,the proportion of Y/G is 2.8/1,the foaming effect is best. The proportion of CMC/PVAL ratio is the most significant factor on the foaming behavior. In addition,the effect of Y/G ratio is also significant. SEM photographs show that the PVAL/CMC porous composites have high porosity,presenting open pore structures which large cells are sleeved by small cells.The average diameter of large cell and small cell is about 180 μm and 15 μm respectively.