Acrylate end group

Due to the fast equilibration of the system, the DP of the product is equal to the ratio of concentration of monomer and low molecular weight formal. A similar approach was used to prepare poly (1,3-dioxolane) containing two acrylate end groups [275]. 

The acrylic end groups are also incorporated in macromolecular networks to improve viscoelastic properties (e.g., acrylic films with liquid elastomers as additives). 

A different way to introduce silicone type sequences in copolymers is to attach acrylate end groups to a poly[oxy(dimethylsilylene)], followed by copolymerization in a vinyl type polymer. The introduction of silicone groups leads to a crosslinked material similar to that obtained with poly(ethylene glycol) dimethacrylate. The structure of a copolymer with silicone crosslinking bridges is shown below ... 

Poly(2-alkyl oxazoline)s having methacrylate or acrylate end groups were prepared by two methods [182]. a) Living polyoxazoline chains, prepared using methyl p-toluene sulphonate as initiator, were end-capped by reaction with metal salts or tetraalkylammonium salts of acrylic or methacrylic acid or a trialky-lammonium salt or trimethylsilyl ester of methacrylic acid (functional termination). b) The living polymers were terminated with water in the presence of Na2C03 to provide hydroxyl-terminated chains. Subsequent acylation with acry-loyl or methacryloyl chloride in the presence of triethylamine led to the formation of the macromonomers. The procedures are outlined in the following Scheme 51. 

Comonomer content (vinyl acetate or methyl acrylate) End groups and dye sites (SO4, HSO3)... 

The thermal lability of the R—C—O—N bond system controls the reversibility of the chain termination and limits also the use of NMRP. SFRP of styrene at about 130°C is studied intensively. In this case, high control and high molar mass products could be achieved. It was found that the thermal autopolymerization of the styrene monomer plays an important role in the mechanism of the reaction. Therefore, first experiments using different monomers in the presence of TEMPO and a radical initiator failed with regard to the control. However, new nitroxide adducts with a different R—O—N bond stabiUty have been developed, for example, by Hawker [14], which work also for styrene derivatives as well as for acrylates. End group functionalization in NMRP can be achieved by using a functional radical initiator in combination with a stable radical or functionalized nitroxide adducts. 

Most of the reactive surfactants already used for emulsion polymerization have their reactive group at the end of the hydrophobic part of the surfactant. This seems to be obvious because the main polymerization process takes place in the latex particle on which that hydrophobic part is, at least, adsorbed if not anchored. Demonstration of the rightness of this choice has recently been done by Sherrington [42] who showed that the other choice (end of the hydrophilic chain) with an acrylated end group led to worse stability, as compared with the equivalent bearing an ethyl ester group. 

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