Novel amphiphilic conetworks based on compatibilized NBR/SBR–montmorillonite nanovulcanizates as membranes for dehydrative pervaporation of water–butanol mixtures

Abstract

Nanocomposite vulcanizates comprising the poorly compatible acrylonitrile butadiene rubber/styrene butadiene rubber blend are homogenized with 20 parts per hundred montmorillonite forms showing various levels of amphiphathicity: slightly hydrophobic (Mont‐25/50) and highly hydrophobic (Mont75/100) as compared to the highly hydrophilic pristine form (Mont‐0). The purpose of the amphiphathicity is to afford simultaneous binding sites for the poorly compatible components. Thus maximum compatibility is reached with either Mont‐75 or Mont‐50 which improves the mechanical properties. Scanning electron microscopy corroborates cocontinuous morphology. Water vapor permeation through sheets/membranes fabricated from these compositions follows best performance with Mont‐25 followed by Mont‐50 while Mont‐75 and Mont‐100 based membranes acquire an organized continuous drop. This highlights the role of organophilicity in dominating the morphology and performance in pervaporation application. Dehydration of butanol is effective using such membranes with superiority for Mont‐25 based membrane. A plausible model for the transport mechanism was proposed and supported by activation energy calculations for the permeation of the individual components and the sorption affinity measurements as well. All these parameters together suggest the arrest of the n‐butanol within the macrmolecular chains of the membranes, favored by its chemical affinity. This allows therefore a passageway for the water to cross to the other side of the membrane through plasticization of the chains and creation of free volumes which is known as solution diffusion mechanism. POLYM. ENG. SCI., 54:1560–1570, 2014. © 2013 Society of Plastics Engineers

Novel interpenetrating amphiphilic Co‐networks based on compatibilized NBR/SBR‐montmorillonite composites: A study on the oil absorption characteristics

“…On the contrary, the diffusivity shows good correlation with the slope (a) values obtained from the relation V ro / V rf versus e − z (not shown), where it could be simply concluded that, the higher the strengthening action of a given montmorillonite form, the lower the diffusivity. We proved previously that this is basically dictated by the acquired free volume of the resulting interpenetrating co‐networks, which is a function of the extent of organophilization for each inserted clay form.…”

Effect of embedded activated carbon nanoparticles on the performance of polydimethylsiloxane (PDMS) membrane for pervaporation separation of butanol

“…Moreover, it has no harmful effects on the microorganism . The use of hydrophobic membranes such as styrene butadiene rubber (SBR), ethylene propylene diene rubber (EPDM), polytetrafluoroethylene (PTFE), polypropylene (PP), polyurethane (polyether based) (PUR), polyether block‐amide (PEBA), poly(vinylidinedifluoride) (PVDF), poly(methoxy siloxane) (PMS), polydimethylsiloxane (PDMS), poly(1‐(trimethylsilyl)‐1‐propyne) (PTMSP) and polyamide‐imide (PAI) containing cyclodextrin (CD) has been reported in the literature for butanol separation through the process of pervaporation …”

Polyblend Nanocomposites

“…the effects of the same nanofiller concentration on PS/PB blend thin film stability was studied (94). Few papers deal with elastomer-elastomer nanocomposites (95,96).…”