PDMS

Abstract(#br)Statement of problem(#br)Daily disinfection of maxillofacial prosthesis may reduce their service-life and lead to replacement.(#br)Purpose(#br)The purpose of this study was to evaluate possible alterations in the mechanical behavior of two maxillofacial elastomers after application of four different disinfection procedures.(#br)Material and methods(#br)The materials tested were two maxillofacial elastomers, a commercially available polydimethylsiloxane (PDMS) and an experimental chlorinated polyethylene (CPE).

Abstract(#br)This work demonstrates the first study on interfacing of microfluidic chip-based chromatography to flame atomic absorption spectrometry (FAAS) for a simple and fast separation or preconcentration and subsequent determination of species. The developed low-cost polydimethylsiloxane microchip includes 12 microcolumns of conventional C18 (5\u003cce:hsp sp=\"0.25\"/\u003eμm) chromatographic particles, making the parallel chromatographic separation/preconcentration and the direct introduction of the effluent into the spectrometer possible.

Abstract(#br)Surface treatment of polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP) fibers was conducted with coupling agents such as epoxy silane, amino silane, and titanate to improve the adhesion characteristics of PVDF-HFP fibers and polydimethylsiloxane (PDMS). The adhesion strength was largest when 4\u003cce:hsp sp=\"0.25\"/\u003ewt% amino silane was used for surface treatment, showing a 250% improvement compared to the untreated case.

Abstract(#br)Thin film of polydimethylsiloxane (PDMS) was deposited on SiO 2 nanoparticles by chemical vapor deposition, and SiO 2 became completely hydrophobic after PDMS coating. Mixtures of TiO 2 and PDMS-coated SiO 2 nanoparticles with various relative ratios were prepared, and distributed on glass surfaces, and water contact angles and photocatalytic activities of these surfaces were studied.

Abstract(#br)In this paper grafting of mesoporous γ-alumina membranes with monovinyl terminated polydimethylsiloxane (PDMS), using 3-mercaptopropyltriethoxysilane (MPTES) as a linking agent, is described. The grafting performance of the organic moieties on γ-alumina powders was studied by FTIR. Contact angle measurements and solvent permeability tests were used to characterize the membrane properties. The results indicated that grafting reactions were successfully carried out.

Abstract(#br)The dehydration of glycerin solution is an important step in glycerin purification process. In present work, pervaporative dehydration of glycerin solution was studied using HybSi and polydimethylsiloxane (PDMS) pervaporation membranes. The effects of physical property of membrane, operating parameters and glycerin concentrations on the membrane permeate flux and selectivity were examined. The present studies showed that hydrophilic HybSi membrane could provide higher permeate flux as compared to hydrophobic PDMS membrane under an identical operating condition.

Abstract(#br)Open and closed electrowetting-on-dielectric (EWOD) systems based on a spin coated polydimethylsiloxane (PDMS) layer are presented. The PDMS layer acts as both insulation and hydrophobic material. Characterization, through sessile drop experiments, shows the hydrophobic behaviors of the PDMS and saturation of the contact angle at negative bias voltage applied to the droplet.

Abstract(#br)We describe the use of light in a lithographic form of grayscale patterning as a means to program the properties and folding mechanics of flat, thin-film-polymeric materials. In this process, a finely dispersed (phase-separated) mixture of photoresist (SU-8 50) in polydimethylsiloxane (PDMS) is irradiated with ultraviolet light through a photomask. The subsequent photoresist cross-linking in the exposed regions causes changes in the material’s chemo-mechanical properties (notably making it stiffer and more resistant to solvent-induced swelling in the area of exposure).

Abstract(#br)BC (bacterial cellulose) exhibits quite distinctive properties than plant cellulose. The outstanding properties make BC a promising material for preparation of artificial blood vessel. By taking advantage of the high oxygen permeability of PDMS (polydimethylsiloxane) as a tubular template material, a series of BC tubes with a length of 100\u003cce:hsp sp=\"0.25\"/\u003emm, a thickness of 1\u003cce:hsp sp=\"0.25\"/\u003emm and an outer diameter of 4 or 6\u003cce:hsp sp=\"0.25\"/\u003emm were biosynthesized with the help of Gluconacetobacter xylinum .

Abstract(#br)We introduce a simple yet robust method for fabrication of wrinkled polydimethylsiloxane (PDMS) surface exhibiting tunable wettability under applied mechanical strain. Submicrometer-scale periodic grooves were prepared by casting the optical discs such as compact disc (CD) and digital versatile disc (DVD) patterns on PDMS. On wrinkled PDMS, the liquid droplet exhibits an anisotropic wetting resulting in a higher contact angle (CA) in the direction perpendicular to the wrinkle axis.