Biodegradable Polymeric Membranes for Organic Solvent/Water Pervaporation Applications

Abstract

Biodegradable polymers are a green alternative to apply as the base membrane materials in versatile processes. In this study, two dense membranes were made from biodegradable PGS (poly(glycerol sebacate)) and APS (poly(1,3-diamino-2-hydroxypropane-co-polyol sebacate)), respectively. The prepared membranes were characterized by FE-SEM, AFM, ATR-FTIR, TGA, DSC, water contact angle, and degree of swelling, in comparison with the PDMS (polydimethylpolysiloxane) membrane. In the pervaporation process for five organic solvent/water systems at 37 °C, both biodegradable membranes exhibited higher separation factors for ethanol/water and acetic acid/water separations, while the PDMS membrane attained better effectiveness in the other three systems. In particular, a positive relationship between the separation factor and the swelling ratio of organic solvent to water (DSo/DSw) was noticed. In spite of their biodegradability, the stability of both PGS and APS membranes was not deteriorated on ethanol/water pervaporation for one month. Furthermore, these two biodegradable membranes were applied in the pervaporation of simulated ABE (acetone-butanol-ethanol) fermentation solution, and the results were comparable with those reported in the literature.

Different methods of synthesizing poly(glycerol sebacate) (PGS): A review

“…The dynamic mechanical thermal analysis (DMTA) results are consistent across many publications. The temperature at the maximum of the associated peak in tan δ shifts accordingly to lower temperatures, around -20°C, which characterizes the main relaxation process associated with the T g of PGS ( Aghajan et al, 2020 ; Rostamian et al, 2020 ; Martín-Cabezuelo et al, 2021a ; Chang et al, 2021 ).…”

“…The thermal stability of PGS, as evaluated by thermal gravimetric analysis (TGA), is consistent throughout the literature. PGS is stable up to 250°C and shows a single weight loss step between 320°C and 475°C ( Gaharwar et al, 2015 ; Tang et al, 2017 ; Aghajan et al, 2020 ; Rostamian et al, 2020 ; Martín-Cabezuelo et al, 2021a ; Chang et al, 2021 ). The initial degradation temperature starts between 320°C and 350°C, with a peak degradation temperature typically between 435°C and 440°C ( Gaharwar et al, 2015 ; Aghajan et al, 2020 ; Martín-Cabezuelo et al, 2021a ; Piszko et al, 2021a ).…”

“…PGS is considered hydrophilic, with a WCA around 38–94° ( Guo et al, 2014 ; Gaharwar et al, 2015 ; Aghajan et al, 2020 ; Chang et al, 2021 ; Martín-Cabezuelo et al, 2021a ; Tevlek et al, 2022 ). A higher glycerol ratio synthesis promotes decreased WCA as it increases the number of hydroxyl groups.…”