Copolymers silicone-organic

The surface activity of silicones is often exploited by using them as additives. For this reason, aspects of the two most important additive forms, copolymers and surfactants, are also included in this discussion. These two classes come together in the relatively low molecular weight PDMS-poly(alkylene oxide) block and graft copolymers that are commonly used as polyurethane foam stabilizers. Other short-chain silicone surfactants designed for aqueous systems and other silicone-organic copolymers are also available. 

For decades I avoided mixtures or copolymers of organic resins with silicones, even abhorred them, because I did not want the pristine properties of my silicone brain children to be degraded or ruined by adulteration. Now, all manner of siloxane-organic copolymers (such as the polyimide block copolymers) with disciplined structures and admirable properties have been developed. 

Monofunctional Silicone Fluids and Silicone Organic Copolymers... 

Summary Monofunctional silicone fluids and silicone organic copolymers are specialty products which offer the ideal supplement to today s standard silicones and polymers. By use of these materials, desirable silicone properties like certain surface effects are conferred onto organic systems, in most cases without compromising the convenient handling of the base formulations. 

Fig. 3. Appearance of silicone organic copolymers left poly[silicone- o>styrene]...

The most-used silicone lubricants in the fibre finishing applications are polydimethylsiloxane, polymethylphenylsiloxane, oleophilic silicone/organic copolymer (Fig. 5.7a), and poly(glycol silicone copolymer) (Fig. 5.7b). The analysis of silicones can be conducted by FTIR. A strong and often broad absorption in the 1000-1100 cm region can be attributed to the Si-O vibration. A peak at 1100 cm shows the Si-O-Si vibration. A sharp peak at 1260 cm" indicates the Si-( II. stretching absorption.- ... 

Ulman, K. L., G. A. Gornowicz, K. R. Larson, and C-L. Lee. 1989a. Drug permeability of modified silicone polymers. I. Silicone-organic block copolymers./. Contr. Rel. 10 251-260. 

Ulman, K., et al. Drug permeability of modified silicone polymers. II. Silicone-organic graft copolymers. Journal of Controlled Release, 1989, 10, 261-272. Folkman, J. and D. Long, The use of silicone rubber as a carrier for prolonged drug therapy. Journal of Surgical Research, 1964, 4, 139-142. 

Uses Reactive intermediate in the synthesis of silicone-organic copolymers for protective coatings provides a water repellent protective coating for wood, masonry, and metal substrates also for mold release agents, filler treatments (hydrophobic surf.)... 

Chem. Descrip. Methaciyloxypropyl en blocked silicone polymer Uses Crosslinking agent for heat- or radiation-cure coatings, synthesis of silicone/organic copolymers... 

PEG-4 diheptanoate compatibilizer, personal care Methylpropanediol compatibilizer, pigment dispersions Methylpropanediol compatibilizer, polymer alloys Propylene/MA copolymer compatibilizer, polymer blends Propylene/MA copolymer compatibilizer, rubber C20-40 pareth-10 compatibilizer, silicone/organic Cetearyl methicone compatibilizer, silicones Phenyl trimethicone compatibilizer, UV coatings Cetoleth-5... 

Surfactants are used to control cell development. Both cell size and shape are affected to the extent that, without surfactant additives, large irregular cells may develop or the foam may collapse altogether. The most widely used type of surfactant for rigid-closed cell PU foams is based on silicone copolymers, although organic types, such as sulfonated castor oil and amine esters of fatty acids, are also used. 

Much work continues on the development and introduction of "thenno-plastlc silicone rubbers" and a wide variety of both silicone and silicone-organic block copolymers are being evaluated at this time. As with the liquid silicone rubbers the major fabrication advantage being sought is direct processing by injection molding techniques [20]. 

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