To explore the effect of polyethylene glycol additive on mechanical and gas permeation properties of polyvinyl alcohol membranes

Abstract

Polyvinyl alcohol (PVA) membranes were prepared by solution casting and blended with Polyethylene glycol (PEG) in de-ionized water which led to the formation of porous and flexible membranes. Extensive experimentation were performed, in order to find out that at what composition of PEG pores will be generated in the PVA membranes. The PVA polymer is a hard and crystalline thermoplastic so high concentrations of PEG were used, i.e. 40 wt%, 45 wt% and 50 wt%. Fourier Transform Infra-Red spectroscopy (FT-IR) was used to study the existence of different organic groups in the membranes. Tensile testing machine was used to analyze the maximum strength of the prepared membranes and the results showed that it can tolerate 10.96 MPa. Scanning Electron Microscopy (SEM) was used to study the surface structure and morphology of the pure PVA membrane and the membranes containing varying compositions of PEG. It was observed that as the amount of PEG increases, the pores formation occur. The effect of pressure and PEG concentration on CO₂ permeability, CH₄ permeability and CO₂/ CH₄ selectivity was also studied. The porous membrane prepared can be used in the formation of composite membranes as it will help in the improvement of the permeability and also the tensile strength.Keywords

Porous membranes, Polyvinyl alcohol, Polyethylene glycol, Gas separation, Solution casting