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In this study, MMA/BMA copolymer nanoparticles were synthesized in oil-in-water microemulsions that were stabilized by sodium dodecyl sulphate (SDS) and initiated by potassium persulphate KPS. Malefic acid terminated poly(N-acetylethylenimine) (PNAEI) with two different chain lengths was also included in the recipe, as a cosurfactant and a comonomer. FTIR and H-1-NMR proved incorporation of the macromonomer in the structure. High polymerization yields were achieved upto 98%. The viscosity average molecular weights of the copolymers were in the range of 2.77-5.50 x 10(5). The glass transition temperatures of these copolymers were between 50.0 and 63.9 degreesC. The average diameter of nanoparticles were in range of 40-96 nm. It was possible to produce nanoparticles smaller than 100 nm and with narrower size distributions by using much lower concentrations of SDS by including the macromonomers in the microemulsion polymerization recipe. (C) 2004 Elsevier Ltd. All rights reserved.

Block and graft copolymers with poly(N-isopropylacrylamide) and poly[(N-acetylimino)ethylene] (PNAI) sequences were synthesized via PNAI derivatives (macroinitiators or macromers). The polymerization yields for block copolymers synthesized in ethanol, using the PNAI macroinitiator, were low (

A series of functionalized poly(2-oxazoline)s were synthesized by quenching poly(2-methyl-2-oxazoline) living chains (mono- or bifunctional) with maleic acid as nucleophilic agent. By varying the functionality of the initiating system and the ratio of the nucleophile to oxazolinium ends, three different compounds – two macromers and/or an unsaturated polyester – were obtained. The use of a macromolecular proton scavenger was found to be an easy, efficient alternative to the laborious approach performed with triethylamine. The coupling products were copolymerized with styrene by solution or dispersion polymerization.

The photochemical polymerization of methacrylic acid in dilute aqueous solution in the presence of poly(N-acetyliminoethylene) macroazoinitiators was investigated. The reaction development is the result of the superposition of two different template processes. The effect of some factors, such as initiation mode (photolysis or thermolysis), matrix dimension, monomer, and overall concentration on polymerization features was evidenced.

The composition dependence of the glass temperatures of copolymers containing monomeric units with electron-donor and/or electron-acceptor groups shows serious deviations from additivity. For electron-donor/electron-acceptor copolymers these deviations are more or less symmetric and, depending on the length of the spacer between the interacting groups and the methacrylic polymeric backbone, they vary from positive for the short ethyl spacer to negative for longer spacers. Glass temperatures of copolymers of methyl and n-butyl acrylates (methacrylates) with the respective electron-donor or electron-acceptor monomers always show asymmetric deviations from additivity. These deviations are mostly positive and situated on the donor-poor side for the donor copolymers and negative and situated on the acceptor-rich side for the acceptor copolymers. The deviations are more pronounced for the methacrylates and decrease from the methyl to the n-butyl ester.

The possibility of opening cyclic iminoethers and forming linear polymers or copolymers under the action of charge transfer complexes has been studied. The polymerization of 2-methyl-2-oxazoline, acting as donor, proceeds in the presence of various organic electron-acceptors such as tetracyanoethylene 7,7,8,8-tetracyanoquinodimethane and 2,4,7-trinitrofluorenone. Initiation takes place by charge transfer complexes formed between the monomer and the acceptor. With acceptors which possess polymerizable bonds, i.e. tetracyanoethylene and tetracyanoquinodimethane, copolymers are obtained.