Polymers containing poly siloxane products

The preparation of polymers containing pendant or terminal amino acids, peptides, and polypeptides has in the past been limited to organic polymers, and so has neglected inorganic polymers such as siloxanes. A novel series of amino acid functional siloxanes, suitable for use in personal care products, have been prepared and characterized for the first time. Such products can be synthesized by a three-step procedure. The preparation of amino acid siloxanes has now been achieved by hydrosilylation of an unsaturated functional amino acid with three hydrido functional siloxanes tetramethyldisiloxane, containing terminal Si-H groups, poly(methylhydrogen)siloxane (DP = 33) and... 

Poly(hydrosilane)s are stable compounds and can be manipulated in the air only for a short period since they are oxygen sensitive. In order to study the oxidation products, a xylene solution of poly(phenylhydrosilane)(Mw = 2340, Mw/Mn = 1.72) was refluxed (140 °C) for 12 h in a system exposed to the air [15]. Only minor changes were observed by GPC analysis whereas FTIR showed characteristic absorptions due to siloxane-type structures on the polymer backbone. A detailed NMR analysis, based on H NMR, Si INEPT and H- Si HMQC spectroscopies, indicated that the oxidized material contains the units 7-10 shown in Scheme 8.2. In particular, units 7,8 and 9+10 were present in relative percentages of 27%, 54% and 19%, respectively, which mean that more than 70% of the catenated silicons were altered. It has also been reported that silyl hydroperoxides and peroxides are not found as products in the autoxidation of poly(phenylhy-drosilane) [16]. 

Poly(ether.siloxanes) contain a poly(methyl.siloxane) polymer, which may be branched, and poly(eiher)-blocks. Its structure may be linear or comblike. The blocks are connected by Si-O-C- or Si-C- bridges., Si-0-C- linked products can, for example, be produced by reacting branched dimethyl(chloro)siloxy-lerminated poly(methyl-siloxanes) (see Section 4.3.3) with monohydroxy-functional polyCethers. 

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