PDMS

Abstract(#br)A promising new polydimethylsiloxane (PDMS)/organosilica hybrid membrane has been developed and applied to the removal of sulfur from model gasoline by pervaporation. The introduction of organosilicas derived from bis(triethoxysilyl)ethane (BTESE) into the PDMS matrix led to a simultaneous improvement of permeance and selectivity of the resultant membrane.

Abstract(#br)Separation of ethanol/water mixtures through classical separation methods, like distillation, are very energy consuming. Pervaporation is an alternative membrane separation process with much lower energy demand, but still lacking high performance membranes with sufficient flux-selectivity properties. In this study, polydimethylsiloxane (PDMS) based mixed matrix membranes (MMMs) were developed and their pervaporation performance investigated. The fillers consist of hollow spheres (HS) covered with a shell of silicalite-1 crystals.

Abstract(#br)Polydimethylsiloxane (PDMS) reinforced by nanoclay platelets exhibits excellent mechanical properties for microfluidic systems. We tested PDMS-clay nanocomposite thin films under flat-ended cylindrical indentation and measured the elastic modulus and shear strength. A simple formulation based on a shear-lag model, fed by numerical simulations, was introduced to estimate the interfacial shear strength of thin films. Increase in the nanoclay content improved the elasticity of PDMS-clay thin films but reduced their interfacial shear strength.

Abstract(#br)Vapor permeation (VP) is applied to be integrated with ethanol fermentation as an in situ product recovery technique which could avoid the ethanol inhibition in this study. The polydimethylsiloxane o(PDMS) membrane is used in separating ethanol from model ethanol/water mixture and fermentation integrated processes. And the performance of VP-fermentation process is investigated and compared to that of Pervaporation (PV)-Fermentation and batch fermentation processes. Experimental results show that the ethanol removal is successfully achieved, while it still suffers low flux.

Abstract(#br)Considerable efforts have been devoted to finding economic and simple preparation methods for polydimethylsiloxane (PDMS) superhydrophobic membrane in past decades. This study provides a simple method to electrospin PDMS membrane using poly (methyl methacrylate) (PMMA) as carrier polymer. Effects of PMMA concentration, PDMS/PMMA mass ratio and main parameters of electrospinning process (voltage and injection rate) were investigated to obtain superhydrophobic membrane with high water contact angle (WCA).

Abstract(#br)A fast processing route of aspheric polydimethylsiloxane (PDMS) lenses array (APLA) is proposed via the combined effect of inverted gravitational and heat-assisted forces. The fabrication time can be dramatically reduced to ~30\u003cce:hsp sp=\"0.25\"/\u003es, compared favorably to the traditional duration of ~2 hours of repeated cycles of addition-curing processes. In this paper, a low-cost flexible lens can be fabricated by repeatedly depositing, inverting, curing a hanging transparent PDMS elastomer droplet on a previously deposited curved structure.

Abstract(#br)We demonstrate a facile single step laser treatment process to render a polydimethylsiloxane (PDMS) surface superhydrophobic. By synchronizing a pulsed nanosecond laser source with a motorized stage, superhydrophobic grid patterns were written on the surface of PDMS. Hierarchical micro and nanostructures were formed in the irradiated areas while non-irradiated areas were covered by nanostructures due to deposition of ablated particles.

Abstract(#br)Commercial cotton fabric was coated with SiO 2 nanoparticles wrapped with a polydimethylsiloxane (PDMS) layer, and the resulting material surface showed a water contact angle greater than 160°. The superhydrophobic fabric showed resistance to water-soluble contaminants and maintained its original superhydrophobic properties with almost no alteration even after many times of absorption-washing cycles of oil. Moreover, superhydrophobic fabric can be used as a filter to separate oil from water.

Abstract(#br)Free-standing zeolitic imidazolate framework-71 (ZIF-71)/polydimethylsiloxane (PDMS) nanocomposite membranes with 0, 5, 25 and 40\u003cce:hsp sp=\"0.25\"/\u003ewt% ZIF-71 loadings were prepared and the pervaporation separation performance for ethanol and 1-butanol from water was measured. ZIF-71 was stable in water for seven days (both at room temperature and 60\u003cce:hsp sp=\"0.25\"/\u003e°C); the crystal structure and morphology remained the same. ZIF-71/PDMS composite membranes were formed through addition cure and condensation cure methods.

Abstract(#br)Sedimentation of silicalite-1 occurs in the fabrication of thin silicalite-1 filled polydimethylsiloxane (PDMS) hybrid composite membranes if the viscosity of membrane solution is low, which makes this preparation challenging. In this work, a new method that use a platinum catalytic agent to assist the pre-polymerization of PDMS polymer to increase the viscosity of the membrane solution was studied.