Polymers organo-silicon

Floyd, D. T. Jenni, K. R. Silicone Polymers, Organo-Modified (Application in Personal Care Products). In Polymeric Materials Encyclopedia, Salamone, J. C., Ed. CRC Press Boca Baton, 1996 Vol. 10, pp 7677-7688. 

Primary interest was in the barrier properties obtained from plasma organo-silicones and from inorganic "SIN" coatings. Spectral grade HMDSO was used in the former case, while mixtures of SiH and NH were used to produce the SIN structures. The substrate in much or the work was DuPont Kapton type H polylmide film, 51 pm thick. Substrate temperatures extended to 450 C, as described earlier (6). The thickness of plasma-polymer deposits was about 0.5 pm. Moisture permeation was evaluated by the routine of ASTME-96-53 T (water vapor transmission of materials in sheet form). Additional, more precise data, were obtained with both a Dohrmann Envirotech Polymer Permeation Analyser, modified as previously described (6), and a Mocon "Permatran W" moisture permeation apparatus. 

As stated, the capability of plasma deposits to reduce the access of water to corrosion-sensitive surfaces may be an important motivation for their application in corrosion protection. In order to study this property, Kapton polyimide film was selected as the substrate because of its high inherent permeability to water and its ability to resist elevated temperatures. The response of Kapton film overcoated by PPHMDSO to the permeation of water vapor is shown in Fig. 1. Clearly, the presence of the organo-silicone plasma film greatly reduces water permeation. The magnitude of the effect is much enhanced when plasma polymers are produced at high T and p. 

See under Siloxanes in article on Silanes in this Vol for the definition and a brief description of the basic molecular structure. The name silicone was created by F.S, Kipping as an analogy to ketones. However, his silicane-diols , (Aryl)2Si(OH)2 could not be dehydrated to silicones but always condensed to higher mw Si—0—Si compds. These structures were then (early 1900s) referred to as silicones. In time the name has come to represent any organo-silicon oxide polymer, such as polydimethy-siloxane (see below) ... 

Silicone polymer technology rests in practice upon the preparation of reactive substituted silanes from silicon metal and the subsequent conversion of these reactive substances, usually through stepwise hydrolysis and condensation reactions, into polysiloxanes. Thus the hydrolysis of these reactive intermediates is a fundamental process, the nature and implications of which have demanded increasing attention as organo-silicon chemistry and technology have developed. 

H9. Hunter, M. J., E. L. Warrick, J. F. Hyde, and C.C. Currie Organo-silicon polymers II. The open chain dimethyl oxanes with trimethyl-siloxy end groups. J. Am. Chem. Soc. 68, 2284—22 (1946). 

However, in order to facilitate students and "non-silicon" scientists an easier access to the ongoing research on the basis of the relevant historical background, we decided to split this volume in two parts, each with a comprehensive introduction, one on molecular and one on polymer and solid state (organo)silicon chemistry. 

Andrianov, K.A. Organo-silicon Compounds Goskhi-mizdat Moscow, 1955 (in Russ.). Andrianov, K.A. Organo-silicon Polymer Compounds Gosenergoizdat Moscow, 1946 (in Russ.). 

A novel extension of the metal-induced coupling of diynes involves the preparation of the red, moisture-sensitive zirconocene-containing polymer 5.39 (Eq. 5.18) with Mw=37,000 (PDI = 2.1) by GPC (relative to polystyrene) [101], Related organo-silicon polymers and macrocycles derived from the zirconocene coupling of MeC = CSiMe2C6H4SiMe2C = CMe have also been reported [102, 103],... 

Silicone. Organo-silicon polymers some of which can be used up to a temperature... 

Polysiloxanes or silicones describe a family of organo-silicon compounds and represent the most commercially important inorganic polymer. The polymer backbone is... 

Between 1899 and 1944 F. S. Kipping of Nottingham University laid the basis of modern organo-silicon chemistry with the issue of more than 50 major papers, mainly in the Journal of the Chemical Society. Although he was not interested in polymers and indeed does not even appear to have foreseen any possible application of organo-silicon compounds some of his discoveries, particularly those concerning the preparation of intermediates, have been of considerable technical importance. 

The surface properties of particles are very important with respect to their end use. Many particles are used for fillers and to impart properties that enhance a materials function. In order to do so, the particles need to be compatible with the environment into which they are placed. Often this is in a polymer matrix such as a film. To enhance particle compatibility of the surface of 2-5 pm silica particles and silica glass beads, surface modification of these particles was carried out. Surface modifications were accomplished by surface polymerization, surface polymer grafting, by surface dendrimerization and by developing organo-silicone particles. The surfaces obtained can have a wide variety of properties, fi om highly hydrophilic to highly hydrophobic, from anionic and cationic to nonionic, as well as being environmentally responsive. 

The silicon chemistry, however, is still developing and new stmctures, new reactions, and new interesting materials are being continuously discovered. Therefore, it seemed reasonable to mention in this chapter also the other, less frequendy reviewed, polymerizable organo silicon monomers and processes leading to the corresponding polymers and copolymers. 

In view of the evident structural changes produced in organo-silicon plasma polymer films as a result of thermal post-treat-... 

Silicone fluids containing Si—H groups are also used for paper treatment. The paper is immersed in a solution or dilute emulsion of the polymer containing either a zinc salt or organo-tin compound. The paper is then air-dried and heated for two minutes at 80°C to cure the resin. The treated paper has a measure of water repellency and in addition some anti-adhesive properties. 

Silicone fluids can be discussed in two categories inert fluids and functional fluids, the latter including silicon-functional and organo-functional210 (modified) polymers. The methods of synthesis of functional siloxanes have recently been reviewed.378... 

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