Silicon biodegradable

This review discusses the hydrolysis mechanism underlying mesoporous silicon biodegradability the factors affecting typical kinetics of that biodegradability, together with techniques used to date to tune those kinetics and timescales achieved. 

Current polymeric entubulization repair methods for peripheral nerve regeneration use various nondegradable and biodegradable materials. The most common nondegradable material investigated has been silicone rubber. Medical grade silicone rubber, polydimethylsiloxane, maintains its shape and can be filled with neurotrophic factors or extracellular... 

N, Al-Dimethylserotonin, 2 92 Dimethylsilanediol biodegradability of, 22 605 in silicone polymerization, 22 556 Dimethylsilicone fluids... 

See also Biodegradable polymer networks Filled silicone networks Interpenetrating networks (IPNs) Model silicone networks Monodisperse model networks ... 

In dentistry, silicones are primarily used as dental-impression materials where chemical- and bioinertness are critical, and, thus, thoroughly evaluated.546 The development of a method for the detection of antibodies to silicones has been reviewed,547 as the search for novel silicone biomaterials continues. Thus, aromatic polyamide-silicone resins have been reviewed as a new class of biomaterials.548 In a short review, the comparison of silicones with their major competitor in biomaterials, polyurethanes, has been conducted.549 But silicones are also used in the modification of polyurethanes and other polymers via co-polymerization, formation of IPNs, blending, or functionalization by grafting, affecting both bulk and surface characteristics of the materials, as discussed in the recent reviews.550-552 A number of papers deal specifically with surface modification of silicones for medical applications, as described in a recent reference.555 The role of silicones in biodegradable polyurethane co-polymers,554 and in other hydrolytically degradable co-polymers,555 was recently studied. 

POLYDIMETHYLSILOXANE. A silicone polymer developed for use as a dielectric coolant and in solar energy installations, It also may have a number of other uses. It is stated to be highly resistant to oxidation and biodegradation by microorganisms. It is degradable when exposed to a soil environment by chemical reaction with clays and water, by which it is decomposed to silicic acid, carbon dioxide, and water. 

The highly effective surface active agent, Decon 90, which is claimed to be suitable for virtually all laboratory cleaning applications. It is totally rinsable, phosphate free, biodegradable and non-toxic. It is particularly suitable for silicone oils, greases, polymeric residues and tars. 

The Sesame is designed so that molders can use a smaller runner and sprue, which gives them more control over the amount of plastic and pressure used to form the part itself. A smaller runner and sprue also means less material waste. While screw-and-barrel systems waste as much as 99.7% of the shot material, the Sesame wastes less than 80%. This is particularly important when molding expensive materials like biodegradable plastics, which cost as much as 10 per gram. The Sesame can handle any type of moldable plastic, as well as silicone rubber. Super-small medical parts that have been molded by the machine include ... 

Numerous microfabrication techniques have been used to produce a wide range of implantable and oral drug delivery systems using materials ranging from silicon, glass, silicone elastomer, and plastics. Fabrication techniques have rapidly evolved to produce nanoscale objects and therapeutic systems using polymeric materials as the substrate due to their biodegradable nature. There are a number of different synthetic polymer systems that have been developed for this type of application, and the most common ones are listed below ... 

We make a mention of phosphate fibers, or more appropriately polyphosphate fibers, that were developed by Monsanto Co. as a replacement for asbestos fibers (Griffith, 1995). Basically, the silicon atoms of asbestos were replaced by phosphorus atoms. These polyphosphate fibers were supposed to be a kind of safe asbestos fiber. However, Monsanto did not commercialize these fibers because of a possible vulnerability to lawsuits. The safety feature of polyphosphate fibers stems from the fact that they are composed of components that are constituents of the human body and are thus biodegradable. The polyphosphate fibers developed by Monsanto were similar to asbestos fibers in terms of their insulating and nonflammable characteristics. 

The combination of both the biodegradability and the stability towards hydrolysis is unique in the field of well known silicone surfactants and will ensure the widespread application of trimethylsilane based surfactants. Considering all these facts all applications for which trisiloxane surfactants are already used or at least recommended are opened up in general for the new silane surfactants. Furthermore, applications now can be taken into consideration for which the hydrolytically unstable trisiloxane derivatives failed in the past. 

Functions as a co-emulsifier for silicone in cleaner polishes and mold release agents, and as an all purpose oil and fat emulsifier in industrial lubricants. For textile applications, this biodegradable, oil-soluble, water-dispersible ether is used as an emulsifier for mineral oil in lubricants such as coning oils. When sulfated, it forms a high-foaming anionic surfactant. 

Heinen, W., 1978. Biodegradation of silicon-oxygen-carbon- and silicon-carbon-bonds by bacteria. In G. Bendz and J. Lindqvist (Editors), Biochemistry of Silicon and Related Problems. Nobel Symposium, Stockholm, Plenum, New York and London, pp. 129— 147. 

The compositions consist of one or more matrix-forming polymers, such as biomedical PU, biomedical silicones or biodegradable polymers, and antimicrobial agents, especially a synergistic combination of a silver salt and chlorhexidine or its salts. 

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