Morphological, mechanical and gas-transport characteristics of crosslinked poly(propylene glycol): homopolymers, nanocomposites and blends

• Published in: Polymer (Guilford) Vol. 45; no. 17; pp. 5941 - 5950
• Main Authors: Patel, Nikunj P., Aberg, Christopher M., Sanchez, Angelica M., Capracotta, Michael D., Martin, James D., Spontak, Richard J.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 05.08.2004; Elsevier
• Subjects: Applied sciences; Composites; Exact sciences and technology; Forms of application and semi-finished materials; Nanocomposite; Polymer industry, paints, wood; Polymer membrane; Reverse-selective; Technology of polymers; Polymer membrane; Reverse-selective; Nanocomposite; Transport properties; Organic clay; Polymer blends; Montmorillonite; Experimental study; Silica; Ethylene oxide polymer; Gas permeability; Acrylate polymer; Reverse -selective; Propylene oxide polymer; Concentration effect; Crosslinked polymer; Selective permeability
• ISSN: 0032-3861; 1873-2291
• DOI: 10.1016/j.polymer.2004.06.024

Linear polyethers possess unusually high CO 2 solubility and, hence, selectivity due to the presence of accessible ether linkages that can interact with the quadrupolar moment of CO 2 molecules. In this work, membranes derived from crosslinked poly(propylene glycol) diacrylate (PPGda) oligomers differing in molecular weight ( M), as well as PPGda nanocomposites containing either an organically-modified montmorillonite clay or a methacrylate-terminated fumed silica are investigated and compared with highly CO 2-selective poly(ethylene glycol) diacrylate (PEGda) homopolymer and nanocomposite membranes previously reported. The rheological and permeation properties of PPGda depend sensitively on M, with the elastic modulus decreasing, but CO 2 permeability and CO 2/H 2 selectivity increasing, with increasing M. Incorporation of either nanofiller into PPGda enhances the elastic modulus and reduces the gas permeability in the resultant nanocomposites without strongly affecting CO 2/H 2 selectivity. Blending PPGda and PEGda prior to chemical crosslinking yields binary membranes that exhibit intermediate gas-transport properties accurately described by a linear rule of mixtures.