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Free-radical solution copolymerization of acrylamide (AAm) and of a disubstituted acrylamide derivative, N-acryloylmorpholine (NAM), with N-acryloxysuccinimide (NAS) was investigated with the aim to obtain a copolymer of at least 100,000 g mol⁻¹. Different polymerization conditions likely to increase the molecular weight were studied such as monomer and initiator concentrations, temperature, and nature of the solvent. The molecular weights were determined by SEC using a light-scattering detector. The grafting of end-functionalized polysaccharide chains onto such high molecular weight poly(NAM-co-NAS) was performed and a graft copolymer bearing a high number of saccharidic branches was obtained. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1808–1816, 2003

The core–shell particles considered were poly(butyl acrylate) core/epoxy groups functionalizing the poly(methyl methacrylate) shell. Physical and thermomechanical properties of benzyl dimethylamine (BDMA)-catalyzed diglycidyl ether of bisphenol A (DGEBA)/dicyandiamine epoxy networks toughened with core–shell particles were studied. The blends were prepared under well-defined processing conditions. The resulting properties were found to depend on the state of the dispersion of the particles in the prepolymer matrix before crosslinking. These particles were dispersed at different volume fractions in order to vary the interparticle distance. The relationships between the size of the core–shell particles and the level of toughening are reported. Static mechanical tests were performed in tension and compression modes on these core–shell polyepoxy blends. A slight decrease in the Young's modulus and an increase in the ability to plastic deformation were observed. Using linear fracture mechanics (LEFM), an improvement of the fracture properties (KIC) was measured. By varying the volume fraction of core–shell particles, an optimum toughness improvement was found for an interparticle distance equal to 400 nm (with an average particle size of 600 nm). © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 849–858, 1999

The covalent immobilization of bovin serum albumin (BSA) onto maleic anhydride-alt-methyl vinyl ether copolymers (MAMVE) was successfully achieved under aqueous conditions. The grafting reaction was shown to be controlled by attractive electrostatic interactions and so took place at a low salt concentration. Under these conditions, the covalent binding reaction was quite efficient, reproducible, and complete within 20 min. The maximum loading capacity of the polymer was of 20 BSA molecules per polymer chain. This preliminary study demonstrated that the immobilization of proteins in an aqueous medium could be an efficient process, despite the existing hydrolysis of the functional polymer by water molecules. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 1565–1572, 1999

Maleic anhydride-co-methyl vinyl ether copolymers were used as reactive polymers to link oligodeoxyribonucleotides (ODN) to make oligonucleotide-copolymer conjugates of potential applications in diagnostics. The anhydride moieties of the copolymers were used for the covalent binding, via the formation of a peptide bond, on reaction with DNA probes that were amino modified at the 5' position. The best coupling yields were obtained by carrying out the reaction in a DMSO-borate buffer (95/5 volume ratio) mixture at high ionic strength. Copolymers and ODN-copolymer conjugates were characterized by size exclusion chromatography and multiangle laser light scattering detection. The average molecular weights of the formed conjugates were relatively high, in the 10⁶ g/mol range, resulting from the crosslinking of several copolymer molecules during coupling. Coupling DNA probes onto smaller molecular weight polymers did not result in the formation of very high molecular weight conjugates showing that copolymer chain interpenetration was a determining factor of the crosslinking process that occurs during the coupling reaction. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65: 2567–2577, 1997