Polydimethylsiloxane graft copolymers

Schunk TC, Long TE. Compositional distribution characterization of poly(methyl methacrylate)-graft-polydimethylsiloxane copolymers. J Chromatogr A 1995 692 221-232. 

Surface active agents are important components of foam formulations. They decrease the surface tension of the system and facilitate the dispersion of water in the hydrophobic resin. In addition they can aid nucleation, stabilise the foam and control cell structure. A wide range of such agents, both ionic and non-ionic, has been used at various times but the success of the one-shot process has been due in no small measure to the development of the water-soluble polyether siloxanes. These are either block or graft copolymers of a polydimethylsiloxane with a polyalkylene oxide (the latter usually an ethylene oxide-propylene oxide copolymer). Since these materials are susceptible to hydrolysis they should be used within a few days of mixing with water. 

Fig. 10 Plots of Le/f-cw vs. dimensionless graft density a (1) PS brushes prepared by adsorption of PS-polydimethylsiloxane block copolymers (Mw,ps = 60000) and 0 (Mw,ps = 169000) [21,22]. (2) PEO brushes prepared by adsorption of PEO-PS block copolymers A (Mw.peo = 30800) and V (Mw.peo = 19600) [201]. (3) PMMA brushes prepared by surface-initiated ATRP (M = 31 300 267400). Data reprocessed from [116,117]...

Most dispersion polymerizations in C02, including the monomers methyl methacrylate, styrene, and vinyl acetate, have been summarized elsewhere (Canelas and DeSimone, 1997b Kendall et al., 1999) and will not be covered in this chapter. In a dispersion polymerization, the insoluble polymer is sterically stabilized as colloidal polymer particles by the surfactant that is adsorbed or chemically grafted to the particles. Effective surfactants in the dispersion polymerizations include C02-soluble homopolymers, block and random copolymers, and reactive macromonomers. Polymeric surfactants for C02 have been designed by combining C02-soluble (C02-philic) polymers, such as polydimethylsiloxane (PDMS) or PFOA, with C02-insoluble (C02-phobic) polymers, such as hydrophilic or lipophilic polymers (Betts et al., 1996, 1998 Guan and DeSimone, 1994). Several advances in C02-based dispersion polymerizations will be reviewed in the following section. 

The same authors attempted copolymerization of these silicone — type macromonomers with different monomers (e.g. styrene) with the aim of synthesizing graft copolymers. a,ra-Diunsaturated polydimethylsiloxanes were also synthesized by the same method starting from i,m-dichlorodimethylsiloxane oligomers. 

Nagase Y, Naruse A, and Matsui K. Chemical modification of polysulphone. 2. Gas and liquid permeability of polysulpho-ne/polydimethylsiloxane graft copolymer membranes cf Polymer. 1990 31(1) 121-125. 

CAS 64365-23-7 68937-54-2 68938-54-5 Synonyms Dimethylmethyl (polyethylene oxide) siloxane Dimethylsilox-ane/glycol copolymer Polyoxyethylene-grafted polydimethylsiloxane Polysiloxane polyether copolymer Siloxanes and silicones, dimethyl, hydroxy-terminated, ethoxylated propoxylated Classification Silicone glycol surfactant... 

Synonyms Dimethylsiloxane (propylene oxide-ethylene oxide) block copolymer Poly [dimethylsiloxane-co-methyl (3-hydroxypropyl) siloxane-graft-poly (ethylene/propylene glycol) Polydimethylsiloxane/EO-PO copolymer Siloxanes and silicones, dimethyl, 3-hydroxypropyl methyl, ethoxylated, propoxylated ClassiTication Silicone... 

Living polymerization created the idea of Macromer (proposed by R. Milkovich, generic term is macromonomer) for synthesizing a graft copolymer of well-controlled structure. We reported the synthesis of polydimethylsiloxane (PDMS)... 

Polydimethylsiloxanes achieve high concentrations at boundaries between different phases which accounts for applications such as release agents and defoamers. The combination of organic polyalkylene oxide pendants on the inorganic backbone of polydimethylsiloxane adds the ability to control wetting and surface tension. A typical structure is shown below and is alternately referred to as a block, graft, or pendant copolymer system. In earlier technology versions, the propyl link between the alkylene oxide and polysiloxane was replaced by a direct Si-O-C bond which is not hydrolytically stable. 

Scheme 6.9 (a) Urethane graft-co-(septadecafluorodecylacrylate)-[fns(trimethylsiloxy silylpropyl acrylate)] copolymers, taken from Ref. [40] (b) polydimethylsiloxane with an epoxide end group grafted onto afluoropolymer, taken from Ref. [41] (c) grafting of PDMS-NCO onto PTFE-co-VAc-co-VA. Taken from Ref. [43]. 

Kumaki, X, Sisido, M. and Imanishi, Y. (1985) Antitbrombogenicity and oxygen permeability of block and graft copolymers of polydimethylsiloxane and polv(o-amino acid)./. Biomed. Mater. Res., 19, 785-811. 

The surface of the magnetite particles modified with aminosilane (Ma-APTES) or with polydimethylsiloxane-carboxy-terminated poly(ethylene oxide) graft copolymer (Ma-PDMSgPEO-COOH) was carefully followed using XPS data... 

Dascalu, A.I. Tigoianu, R. Harabagiu, V. Pinteala, M. Simionescu, B.C. (2010), Synthesis and micellization of polydimethylsiloxane-carboxy-terminated px)ly(ethylene oxide) graft copolymer in aqueous and organic media and its application for the synthesis of core-shell magnetite perticles. e-Polymers, no. 093. 

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