Mohammad Khorsand-Ghayeni - Iran Polymer and Petrochemical Institute, P.O. Box: 14965/115, Tehran, Iran
Jalal Barzin - Iran Polymer and Petrochemical Institute, P.O. Box: 14965/115, Tehran, Iran
Mojgan Zandi - Iran Polymer and Petrochemical Institute, P.O. Box: 14965/115, Tehran, Iran

Nowadays, due to biocompatibility, good chemical resistance, thermal stability and mechanical properties, polyethersulfone (PES) used as the membrane forming material. In this work, PES membranes with a combination of phase separation techniques by absorbing water vapor from the atmosphere (dry separation) and then immersed in a coagulation bath (wet separation) were prepared. The effect of humidity, retention time, and percentage of polyethylene glycol (PEG) on polymer membrane structure in two percent (15% and 25%) of additive was examined. Scanning electron microscopy (SEM) showed by controlling the process conditions, common asymmetric morphology structures and the canal-like cavities could be changed into symmetric structure with closed and open pores. The results of the tests conducted on samples of flux and porosity of membrane have confirmed these observations as well

polyethersulfone, relative humidity, symmetric and asymmetric membranes, phase separation