We have linked the structural and dynamic properties in aqueous solution of amphiphilic charged diblock copolymers poly(butyl acrylate)-b-poly(acrylic acid), PBA-b-PAA, synthesized by controlled radical polymerization, with the physico-chemical characteristics of the samples. Despite product imperfections, the samples self-assemble in melt and aqueous solutions as predicted by monodisperse microphase separation theory. However, the PBA core are abnormally large; the swelling of PBA cores is not due to AA (the Flory parameter PBA/PAA , determined at 0.25, means strong segregation), but to h-PBA homopolymers (content determined by Liquid Chromatography at the Point of Exclusion and Adsorption Transition LC-PEAT). Beside the dominant population of micelles detected by scattering experiments, capillary electrophoresis CE analysis permitted detection of two other populations, one of h-PAA, and the other of free PBA-b-PAA chains, that have very short PBA blocks and never self-assemble. Despite the presence of these free unimers, the self-assembly in solution was found out of equilibrium: the aggregation state is history dependant and no unimer exchange between micelles occurs over months (time-evolution SANS). The high PBA/water interfacial tension, measured at 20 mN/m, prohibits unimer exchange between micelles. PBA-b-PAA solution systems are neither at thermal equilibrium nor completely frozen systems: internal fractionation of individual aggregates can occur.

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We combined several analytical techniques (NMR, matrix assisted laser desorption ionizationtime-of-flight mass spectroscopy MALDI-TOF MS, GPC, functional analysis on the first block, liquid chromatography at the point of exclusion adsorption transition LC-PEAT, and capillary electrophoresis CE) to analyze and quantify the characteristics of homopolymer precursors and amphiphilic diblocks synthesized by controlled radical polymerization process (CRP). We present here a detailed quantitative characterization of amphiphilic diblock copolymers (poly(butyl acrylate)-poly(acrylic acid) or PBA-b-PAA, and poly(di(ethylene glycol) ethyl ether acrylate)-poly(acrylic acid) or PDEGA-b-PAA). The samples were synthesized in ethanol by macromolecular design via inter-exchange of xanthate (MADIX), a reversible addition fragmentation transfer (RAFT) polymerization process using xanthates as control agents. The analytical results have permitted a determination of the transfer constant of xanthate C Xa (≈ 2.7 and 1.5 for respectively PBA and PDEGA) and the transfer constant to solvent C s (≈ 6 × 10 -4 ). In the final diblock products, homopolymer side products were characterized. The amount of hydrophobic homopolymer was quantified by a specially developed LCPEAT technique in critical conditions for PBA. The hydrophilic homopolymer h-PAA amount was determined by quantitative capillary electrophoresis CE experiments. These analytical approaches allowed the quantification of the side products in a CRP system as well as the improvement of the reaction conditions via a thorough knowledge of the reaction mechanism.