聚二甲基硅氧烷

Abstract(#br)To enhance sample signals and improve homogeneity in matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF) analysis, a simple, rapid, and efficient sample preparation method was developed in this study. Polydimethylsiloxane (PDMS) was coated on a stainless steel MALDI plate, forming a transparent, hydrophobic surface that enhanced sample signals without producing observable background signals.

Abstract(#br)Due to the absence of a significant chromophore, Simethicone raw material and finished product analysis is achieved using a FTIR-based method that quantifies the polydimethylsiloxane (PDMS) component of the active ingredient. The method can be found in the USP monographs for several dosage forms of Simethicone-containing pharmaceutical products. For soft gelatin capsules, the PDMS assay values determined using the procedure described in the USP method were variable (%RSDs from 2 to 9%) and often lower than expected based on raw material values.

Abstract(#br)Polydimethylsiloxane (PDMS) composites with different weight amounts of multi-walled carbon nanotubes (MWCNT) were synthesised as membranes to evaluate their gas separation properties. The selectivity of the membranes was investigated for the separation of H 2 from CH 4 gas species. Membranes with MWCNT concentrations of 1% increased the selectivity to H 2 gas by 94.8%. Furthermore, CH 4 permeation was almost totally blocked through membranes with MWCNT concentrations greater than 5%.

Abstract(#br)A modified procedure for the production of porous polydimethylsiloxane (PDMS) beads is presented which results in non-polar polymer beads with microscale concavity and therefore an increased surface-area-to-volume ratio. The key modification is the simple addition of a platinum catalyst to the emulsion prior to thermal curing. Elemental analysis of beads indicates the presence of platinum at the center of many of the indentations, which provides insight into the synthetic mechanisms.

Abstract(#br)This study explores the radiation characteristics of carbon nanotubes-based polymer composite for high-energy proton shielding applications in aerospace industry. Nanocomposites of single-walled carbon nanotubes (SWCNTs) dispersed in polydimethylsiloxane (PDMS) were tested under monoenergetic proton beams. The stopping ranges of the nanocomposite (PDMS/SWCNT) were calculated and compared to those of the pure PDMS and aluminum (Al).

Abstract(#br)We propose a simple method to elaborate a filler-free stretchable PDMS surface strong enough to resist to successive elongation/retraction cycles even at high degree of stretching. It consists in creating free radicals on a filler-containing PDMS surface by argon plasma exposure and reacting them with a filler-free PDMS resin during the crosslinking step. Changes of physical and chemical properties upon plasma modification are monitored by FTIR and XPS spectroscopies, contact angle measurements and atomic force microscopy.

摘要 聚二甲基硅氧烷( PDMS )是一种硅橡胶，具有良好的柔韧性、光学透明性和生物相容性。因此，在硅玻璃等透明材料上制备柔性微光学元件，可以为微流控领域的应用提供可能。我们用质子束( PBW ) ( 1.0 MeV束)在硅玻璃上制备了具有曲面的PDMS微结构。我们发现，硅玻璃上13μm厚的PDMS薄膜仅对600 nC / mm2以上的质子注量敏感，而使用硅衬底时，对4.0 nC / mm2的质子注量敏感。基于PBW过程中硅玻璃表面充电导致有效灵敏度降低的假设，采用Au溅射的方法对硅玻璃表面进行镀膜。在2.0 nC / mm2的条件下，我们可以观察到金包硅玻璃上PDMS的形成。在半透明镀金硅玻璃上制备了高度为13 μm，直径为40 μm的弯曲PDMS结构阵列。

Abstract(#br)The objective of this work is enhancing the clearcoat resistance against simulated tree gum (Arabic gum) using surface active additives including hydroxyl-functional polydimethyl siloxane (PDMS) and hydroxyl-functional silicone polyacrylate which are able to reduce gum adhesion to the clearcoat surface by reducing its surface free energy and work of adhesion. Using a contact angle measuring device, the surface free energy, contact angle and work of adhesion were obtained.

Abstract(#br)In this paper, reactive polyvinylsilazane (PVSZ) is employed as silicate source for poly(dimethylsiloxane) (PDMS) channel surface modification. The PVSZ submicron layer is simply constructed by flushing 1\u003cce:hsp sp=\"0.25\"/\u003ewt.% PVSZ-anhydrous DMF solution into PDMS channel for 1\u003cce:hsp sp=\"0.25\"/\u003emin. After UV and thermal curing, the reactive coating is subjected to hydrolysis reaction in an alkali solution for 1\u003cce:hsp sp=\"0.25\"/\u003eh to convert the consolidated polymer surface to silicate phase.

Abstract(#br)The polypropylene/polydimethylsiloxane/graphite fluoride (PP/PDMS/GF) composites are prepared with dynamic curing technology by simple blending of polypropylene, graphite fluoride and polydimethylsiloxane, and then their superhydrophobic properties are investigated. The results indicates that the static WCA reaches 148° with a sliding angle 6° for surface sandpapered PP/PDMS/GF\u003cce:hsp sp=\"0.25\"/\u003e=\u003cce:hsp sp=\"0.25\"/\u003e100/20/15 composite, which supplies a much economical and convenient method for preparing superhydrophobic materials.