【摘要】 通过羟氨缩合法合成了一系列不同比例"软-硬"段的PDMS-b-PPO共聚物,利用1 HNMR测定组分比,采用溶剂挥发法将其制备成膜并用于乙醇/水的渗透汽化分离,考察了PDMS-b-PPO共聚物的组分比对小分子在膜中溶解扩散性及膜微观结构的影响.利用接触角法测定了PDMS-b-PPO膜的溶解度参数,采用比重法计算了乙醇和水分子在膜中的相互作用参数及扩散系数,并通过AFM和EDS等手段对膜的微观结构进行表征.结果表明,PDMSb-PPO膜具有微相分离的特征结构,随着膜中PDMS浓度的增加,膜的微相分离结构更加明显,乙醇在膜中的溶解和扩散能力明显增强.更多还原

【Abstract】 A series of polydimethylsiloxane-block-polyphenylene oxide(PDMS-b-PPO)copolymers with different compositions of"hard-soft"segments were synthesized through a hydroxyl-amino condensation reaction.The PDMS concentration was calculated based on the 1 H-NMR result of the PDMS-b-PPO copolymers.The PDMS-b-PPO membranes were prepared via a solvent evaporation method and employed in the separation of ethanol/water mixtures by pervaporation.The effects of varying the composition on the mass transfer properties and morphology of the PDMS-b-PPO membranes were studied.The solubility and diffusion properties of ethanol and water in PDMS-b-PPO membranes were tested,and the microphase separation morphologies were observed by AFM and EDS.The results showed that the membranes preferentially absorbed ethanol.With the increasing of PDMS concentration in the PDMS-b-PPO membrane,the diffusion ability of both ethanol and water in the membranes was enhanced,and furthermore,the value for ethanol increased more rapidly than the value for water.更多还原