Mixed matrix membranes of natural rubber-poly (vinyl alcohol) blend filled with zeolite: preparation and characterization

Abstract

Mixed matrix (MM) membranes of natural rubber (NR) – poly(vinyl alcohol) (PVA) blend filled
with zeolite 4A were prepared. PVA was crosslinked with sulfosuccinic acid (SSA) in the immediate presence
of NR to form a semi-interpenetrating polymer network structure. The crosslink of PVA in the MM membrane
was confirmed by FT-IR spectroscopy. The swelling behaviours of the membranes were investigated and the
degree of swelling in water and ethanol was found to increase with increasing PVA content in the membranes
however adding the zeolite more than 10 wt.% leaded to the decreasing of membrane swelling. The states of
water in the membranes were studied using differential scanning calorimeter (DSC). The amount of bound 
water in the membranes increased with increasing PVA but decreased with the amount of zeolite. The thermal
degradation of the MM membrane was determined using TG-DTA analysis. The MM membranes showed a
higher thermal stability compared with pure NR and PVA due to the incorporation of zeolite. The SEM
micrographs of MM membranes showed a well dispersing of zeolite particles in the NR-PVA blend matrix