中文摘要：

以壳聚糖为膜基材,制备壳聚糖基多孔膜,并在超临界二氧化碳中,以丙烯酸（AA）和4-乙烯基吡啶（4-VP）为接枝共聚单体,对壳聚糖多孔膜进行接枝,制备了p H-响应型壳聚糖多孔膜。采用傅里叶变换红外光谱和X射线衍射等对接枝膜的结构进行表征,考察了2种接枝单体的摩尔比及反应压力对壳聚糖膜接枝率的影响,以及接枝膜对蛋白质的吸附。红外结果表明聚丙烯酸与聚4-乙烯基吡啶均接枝到壳聚糖膜上。当AA/4-VP单体摩尔比由3∶1增加至6∶1时,接枝率由7.12%逐渐增大至13.36%,此后呈下降趋势。且随着反应压力的提高,壳聚糖膜接枝率先增长后降低,当反应压力在19 MPa时,得到较高的接枝率（13.36%）。当溶液p H=2~10时,壳聚糖接枝膜的水通量随着p H值的增大而降低。蛋白质吸附实验显示,在p H为4.8时接枝膜获得最大比表面积吸附量5.76 mg/cm2。

英文摘要：

The chitosan porous membrane was prepared using chitosan（ CS） as base material. The CS membrane was modified in sc CO_2,that acrylic acid and 4-vinylpyridine were used as grafting monomers to prepare p H-responsive CS porous membrane. Grafted membrane was characterized by FT-IR and XRD. Effects of grafting monomer mole ratio and reaction pressure on grafting degree of CS membrane were evaluated. The adsorption of bovine serum albumin（ BSA） by grafted CS membrane was investigated. FT-IR proves the existence of grafting monomers. When the AA/4-VP mole ratios is increased from 3∶ 1 to 6∶ 1,the grafting yield increases from 7. 12% to 13. 36%,and then decreases. The grafting yield increases with increasing the reaction pressure from 16 MPa to 19 MPa. However,when the pressure is further increased to 24 MPa,the grafting yield considerably decreases. The water flux of the grafted CS membranes decreases with the increase of p H values from 2 to 10. BSA adsorption experiments show that the maximum specific surface area adsorptive capacity of 5. 76 mg / cm^2 is obtained at p H 4. 8.