Liquid or supercritical carbon dioxide(LCO2or sc-CO2)is an alternative green solvent to coventional organic solvents because of its nontoxic,non-flammable,and non-expensive,characteristics to prepare the CO2-in-water high internal phase emulsion(C/W HIPEs,the internal phase volume fraction ≥74.05%).The C/W HIPEs emulsion can be used to produce the macroporous materials with special construction by the emulsion-templating polymerization method.Using this method,a novel starch-based macroporous material was produced.Firstly,the starch-based macromolecular monomer(S-MA)was synthesized by esterifying the soluble starch with methacrylic anhydride, and its structure was characterized by 1 H-NMR and FT-IR.Then the C/W HIPEs emulsion was prepared using poly(vinyl alcohol)-1788 as the surfactant,CO2as the internal phase,and S-M A solution as the continuous phase. The stability of emulsion was also investigated.The results indicated that the C/W HIPEs emulsion was stable for more than 24 h,w hether or not S-M A in presence,even if the internal phase volume fraction took up to 90% and the surfactant mass concentration was as low as 2×10 -3g/mL.Good stability of HIPEs was necessary to get macroporous materials for the following polymerization of the continuous phase.After the continuous phase was polymerized using the potassium persulfate/N,N,N′,N′-tetramethylethylenediamine as the redox initiation system,starch-based macroporous materials with uniform monolithic materials in the cylindrical interior of the cell were recovered,suggesting no significant shrinkage after the CO2venting.SEM analysis shows that pore-size of these macroporous materials is above 10 μm with open-cell morphology,and these pores can be controlled easily by changing the volume ratio of internal phase and the continuous phase.T hese simple structure features of these materials supported cell grow th and proliferation for tissue engineering applications.%首先将水溶性淀粉结构中的部分羟基用甲基丙烯酸酐功能化,得到淀粉基大分子单体(S-M A);然后以聚乙烯醇-1788为表面活性剂、以二氧化碳为分散相、以S-M A 的水溶液为连续相,制备了水包二氧化碳型高内相乳液(内相体积分数大于74.05%);最后利用乳液模板聚合法制备了大孔材料.采用傅里叶变换红外光谱仪(FT-IR)、核磁共振波谱仪(1 H-NM R)、扫描电镜(SEM)等分析测试手段对 S-M A 的结构、大孔材料的孔径及分布进行了表征,研究了内相体积分数对材料孔径的影响.结果表明:所得高内相乳液具有优良的稳定性,能够稳定存在超过24 h;所得大孔材料的平均孔径在10 μm 以上,且存在相互贯穿的孔结构,该结构有利于细胞的黏附和生长.
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