对外合作

国内合作

首页>对外合作>国内合作

材料学院学术报告十二

Structure Formation of Lsoporous Block Copolymer  Membranes

报告人:Prof.  Dr. Volker Abetz (汉堡大学/德国亥姆霍兹联合会吉斯达赫特中心)

报告人简介:

    Volker Abetz教授1990年获得德国弗赖堡大学博士学位,先后在德国马普高分子研究所、美因兹大学、拜罗伊特大学等机构工作。2004年至2012年任德国基尔大学教授,2013年1月起转入德国汉堡大学化学部任教授。同时, 2002年至今Volker Abetz教授一直担任德国亥姆霍兹联合会吉斯达赫特研究中心高分子研究所所长。

报告内容:

Amphiphilic block copolymers can spontaneously form integral asymmetric  isoporous membranes by evaporation-induced self-assembly.  The parameters influencing the structure  formation will be discussed. The critical structural evolution steps occur  within the first hundred seconds after solvent casting. By using synchrotron  small angle X-ray scattering employing a specially designed solvent casting  apparatus, the kinetics of the structural evolution was monitored  in situ. Sometime after solution casting  first structural features on length scales of 30–70 nm are observed. During the  subsequent period of solvent evaporation the length scales increase continuously  towards a plateau value of 80–120 nm, depending on the molecular weight of the  block copolymer. The time evolution of the characteristic length scales follow a  simple exponential saturation curve for all block copolymers, irrespective of  molecular weight, composition, and addition of salts. This is in agreement with  theoretical models on two-dimensional ordered block copolymer domain formation.  Furthermore, immersion in water during solvent evaporation leads to a nearly  instantaneous increase of the characteristic length scale to its plateau value.  The addition of salts leads to structures with smaller characteristic length  scales, but still following the same kinetic evolution. Morphological results of  membranes and dense bulk materials indicate a different dependence of the  periodic length scale from the molecular weight, as shown by comparison of  investigations by scanning, transmission electron microscopy  and small angle X-ray  scattering.

报告时间:201669 下午15:00

报告地点:创意园327

深圳大学材料学院

201667