Polydimethylsiloxane elastomer

An investigation of the mechanism of adhesive failure of polydimethylsiloxane elastomers was conducted [75]. The study showed that the total adhesive failure energy could be decomposed into energies for breaking chemical bonds, breaking physical bonds and deforming the bulk viscoelastic elastomer. [Pg.698]

The analysis of gas plasma-modified polydimethylsiloxane elastomer surfaces using attenuated total-reflectance FTIR spectroscopy was discussed.636... [Pg.684]

The production of polydimethylsiloxane elastomer comprises three main stages the hydrolytic condensation of dimethyldichlorosilane the depolymerisation of the products of hydrolytic condensation the polymerisaton of dimethylcyclosiloxanes. [Pg.254]

The production of polydimethylsiloxane elastomer relies heavily on the purity of the parent dimethyldichlorosilane, since impurities of other monomers noticeably impair the properties of the elastomer and rubbers based on it. Methyltrichlorosilane has the strongest negative effect when dimethyldichlorosilane with impurities of this monomer is subjected to hydrolytic condensation, linear oligodimethylsiloxane develops branched me-... [Pg.255]

Our industiy manufactures dimethyldichlorosilane of 99.98% purity and 54.85-55% chlorine content. This dimethyldichlorosilane can be used as raw stock in the production of polydimethylsiloxane elastomer without any additional rectification. [Pg.256]

Dimethyldichlorosilane used in the production of polydimethylsiloxane elastomer should meet the following technical requirements ... [Pg.256]

The product of depolymerisation is a mixture of cyclic dimethylsilox-anes with tetramer (mostly [(CH3)2SiO]4 (the boiling point is 175 °C) with an impurity of trimer [(CH3)2SiO]3 (the boiling point is 134 °C) and pen-tamer [(CH3)2SiO]5 (the boiling point is 210 °C). It is used as raw stock in the production of polydimethylsiloxane elastomers SKT, SKTV, SKTN, etc. [Pg.261]

Apart from high-molecular polyorganosiloxane elastomers, such rubbers are also based on low-molecular silicone elastomers with molecular weights from 25000 to 75000, especially polydimethylsiloxane elastomers SKTN. [Pg.270]

Low-molecular polydimethylsiloxane elastomers can be obtained by the polymerisation of a dimethylcyclosiloxane mixture in the presence of alkali ... [Pg.271]

The preparation of low-molecular polydimethylsiloxane elastomers often requires a considerable quantity of alkali, which calls for additional neutralisation. That is why in some cases it is advisable to use special substances (so-called chain growth regulators), which can take part in the reaction of chain transition. The part of regulators can be played by oli-gomethylsiloxanes, which do not have active end groups. Below we give the consumption of some regulators (g, per 1 tonne of polydimethylsiloxane) ... [Pg.271]

When SKTN elastomers are produced, dimethylcyclosiloxanes are polymerised with 2 N potassium hydroxide solution (0.005% of the amount of the polymerised substance) the molecular weight of the polymer is regulated by water supply (diluting the alkali). The raw stock for polymerisation can be the depolymerisate obtained at the depolymerisation stage of the product of hydrolytic condensation of dimethyldichlorosilane in the production of polydimethylsiloxane elastomer SKT. [Pg.271]

At present there are several brands of SKTN A, B, C, D and E, which differ in their viscosity and molecular weight. Similarly to SKTN, one can obtain low-molecular polydimethylsiloxane elastomers which also contain methylphenylsiloxy elements, SKTNPh, SKTNPh-50, etc. [Pg.273]

Of all the known elastomers, polyorganosiloxane elastomers are the most resistant to weather effect they are insensitive to oxidation with oxygen in air and ozone, as well as to UV rays. That is why they do not age even in veiy harsh conditions. E.g., if natural rubber decomposes under the influence of ozone within 5 minutes at 20 °C and within 6 seconds at 100 °C, polydimethylsiloxane elastomer does not decompose even after 60 minutes in ozone at 100 °C. If heated in air to 320 °C, elastomers based on polydimethylsiloxanes, polydimethyl(metylphenyl)siloxanes, etc. only slowly oxidise on the other hand, natural rubber and synthetic organic elastomers decompose at once. [Pg.474]

The high mechanical strength of natural and organic rubbers as used in tires is due to the incorporation of pyrogenic carbon blacks as active fillers. Elastomers of a more polar polymer backbone, such as polyacrylates, polyurethanes or polysulphides, require fillers of higher polarity. In particular the performance of polydimethylsiloxane elastomers (silicone rubber) is basically related to the addition of fumed silica. [Pg.774]

The three key features of LCVD coating ideally suited for biomaterial surface, and the important balance between the bulk properties and the surface properties, could be best illustrated by examples of nanofilms of methane plasma polymer on a contact lens made of polydimethylsiloxane elastomer. Hence, some details of processing factors and their influence on the overall properties of the product are described in the following sections. [Pg.780]

Synonyms Polydimethylsiloxane elastomer Polydimethylsiloxane rubber Polysilicone Silicone mbber IMinition Room-temp, vulcanizing silicone mbber Properties Sol. in org. soivs. dens. 1.12 (20C) low surf, tension Toxicology TDFo (implant, rat) 1500 mg/kg skin and eye irritant questionable carcinogen experimental lumorigen Hazardous Decanp. Prods. Heated to decomp., emits acrid smoke and imtating fumes... [Pg.1339]

Poly (dimethylsiloxane-co-methylphenylsiloxane). See Phenylmethyl/dimethylsiloxane copolymer Polydimethylsiloxane, diacetoxymethyl-terminated. See (Chloropropyl) methylsiloxane-dimethylsiloxane copolymer Polydimethylsiloxane elastomer. See Silicone elastomer... [Pg.3461]

Synonyms Polydimethylsiloxane elastomer Polydimethylsiloxane rubber Polysilicone Silicone rubber... [Pg.3933]

Silane groups formed on the surface of polydimethylsiloxane elastomers by argon or nitrogen gas plasma treatments were determined. Kramers-Kronig transformation of the ATR spectra of standard solutions containing Si-H species allowed construction of calibration plots which were independent of the angle of incidence, crystal coverage and sample refractive index. [Pg.121]

Lai, S. K. Batra, A. Cohen, C., Characterization of Polydimethylsiloxane Elastomer Degradation via Cross-Linker Hydrolysis. Polymer 2005,46,... [Pg.30]

Sharaf, M. A., The Effects of Network Imperfections on the Small-Strain Moduli of Polydimethylsiloxane Elastomers Having High Functionality Cross-Links. Int. J. Polym. Mater. 1992,18(3-4), 237-252. [Pg.188]

Mazan, J. Leclerc, B. Galandrin, N. Couarraze, G., Diffusion of Free Polydimethylsiloxane Chains in Polydimethylsiloxane Elastomer Networks. Eur. Polym. J. 1995, 31(8), 803-807. [Pg.190]

The figure below shows the MALDI-TOF mass spectrum (positive mode) of a sample of a polydimethylsiloxane elastomer, the repeat unit of which is ... [Pg.96]

Replication and Compression of Surface Stractures with Polydimethylsiloxane Elastomer Polymers Structure -Properly Relationships ( 6)... [Pg.27]

Poly [dimethylsiloxane-co-methyl (3-hydroxypropyl) siloxane-graft-poly (ethylene glycol) methyl ether. See DImethylsIloxane/EO copolymer Poly [dimethylsiloxane-co-methyl (3-hydroxypropyl) siloxane-graft-poly (ethyl-ene/propylene glycol). See Dimethylsiloxane/EO-PO copolymer Polydimethylsiloxane elastomer. See Silicone elastomer Polydimethylsiloxane/EO-PO copolymer. See Dimethylsiloxane/EO-PO copolymer... [Pg.2361]

R. luliucd, C. Taylor, W. Kirk Hollis. H/ Si cross-polarization NMR experiments of silica-reinforced polydimethylsiloxane elastomers probing the polymer-fiUer interface. Magn. Reson. Chem., 44 (3), 375-384,2006. [Pg.303]

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