Monomers, vinyl quaternary ammonium

Vinyl monomer polymerization has been photoinitiated with quaternary ammonium salts, an example of the mechanism of which is given in reaction (4), the benzoyl radical being the initiating species.12... 

The cationic copolymerization was carried out in air at 25°C in a nitrobenzene solution using stannic bromide as catalyst, while the anionic polymerization was studied in air with sodium dissolved in anunonia [186]. Although many monomers may be polymerized by quaternary ammonium salts, vinyl acetate does not produce any polymer on treatment with dimethylphenylbenzylammonium chloride [187]. 

Cationic polymers include homopolymers and cationic copolymers obtained by the polymerization of a vinylic monomer with a quaternary ammonium group or a quatemized amine with another soluble monomer in water such as acrylamide and methacrylamide. The most frequently used polymers are those derived from gum guar such as guar hydroxyl propyl triamonium chloride. They are sold under the trade names Jaguar C13S, C17, etc. [12-16]. 

The cyclic diether, 1,3-dioxolane, is recommended by Ferro Corporation as a more benign solvent substitute for chlorinated organic solvents, such as methylene chloride, 1,2-dichloroethane, and 1,1,1-trichloroethane, and for ketones, such as methyl ethyl ketone (MEK). This ethylene glycol-based ether is a suitable solvent under neutral and basic conditions in several major-use areas. It is a powerful solvent for softening and dissolving polymers made from polar monomers, for example, polycarbonates, acrylates, cellulosics urethanes, phenoUcs, nitriles, urea-formaldehydes, and alkyds, as well as polyesters, vinyl epoxys, and halogen-containing polymers. As a reaction solvent it is added as a component to a special quaternary ammonium or phosphonium salt solution for preparation of a vesicular phenoxy resin. Other beneficial uses for the solvent dioxolane, include ... 

Stability and performance of AEM prepared using poly(4-vinyl pyridine-costyrene), quaternized with 1-bromooctane, and deposited on fibrous woven paper was unsatisfactory [189]. Sanchez and coauthors [190] discussed problems related to the use of certain AEMs. They pointed out that the so-called Hoffman degradation that involves attack of a hydroxyl on a-hydrogen in p-position to a quaternary ammonium attached to an aliphatic chain may cause its removal, followed by release of a tertiary amine and formation of a double bond at the end of a broken chain. Attachment of DABCO on short leash prevented chain break due to Hoffman degradation, but release of DABCO and generation of a double bond attached to the chain could take place. Perhaps thermal cross-linking by DABCO of poly(vinyl benzyl chloride) may solve this problem. Sulfonated polymers prepared by polymerization or copolymerization of phosphazene, siloxans, styrene, vinylidene fluoride, and various monomers with aromatic backbones, and possibly with aliphatic spacers, have been used. Various imides as well as PPS, PEK, PEEK, PSU, PEEKK, and PPSU can also be used [190,191]. 

Monomers 4VP, 4-vinylpyridine NIPAAm, jV-isopropylacrylamidc AA, acrylic acid PEGMA, poly (ethylene glycol) methacrylate SPE, MAI-dimethyl-AW2-methacryloyloxycthyl-/V-0-sulfopropyl)amm<>-nium betaine AMPS, 2-acrylamido-2-methyl-l-propanesulfonic acid qDMAEMA, quaternary 2-dimethylaminoethyl methacrylate St, styrene HEMA, 2-hydroxyethyl methacrylate HEA, 2-hydro-xyethyl acrylate DMAEMA, 2-dimethylaminoethyl methacrylate MAA, methacrylicacid NaSS sodium p-styrene sulfonate AC, [(2-acryloyloxy)ethyl]trimethyl ammonium chloride GMA, glycidyl methacrylate NVP, jV-vinylpyrrolidone MAn, maleic anhydride BVE n-butyl vinyl ether AAm, acrylamide DEAAm, MA-diethylacrylamidc DMAAm, MA -dimethylacrylamidc MMA, methyl methacrylate. 

Polymerisation of vinyl toluene in quaternary microemulsions containing cetyltrimethylammonium bromide as the cationic surfactant was studied using laser Raman spectroscopy and dilatometry. The influences of water soluble (potassium peroxodisulphate, ammonium peroxodisulphate) and oil-soluble (azobisisobutyronitrile, benzoyl peroxide) initiators, monomer, surfactant, cosurfactants (n-alcohol and bifunctional alcohols) and temperature on the rates of polymerisation, energy of activation, particle diameter, number of polymer particles, molecular weight of polyvinyl toluene and number of polymer chains per latex particle were investigated. The dependencies of the kinetic and latex size parameters on the initiators and co-surfactants are discussed in terms of the efficiency of the initiators in initiating the polymerisation and on the interfacial partitioning behaviour of various co-surfactants. 19 refs. 

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