Summary: A well‐defined homopolymer of 2‐(diethylamino)ethyl methacrylate has been synthesized by reversible addition‐fragmentation chain transfer (RAFT) polymerization using (4‐cyanopentanoic acid)‐4‐dithiobenzoate as a chain transfer agent. The corresponding protonated homopolymer with a very reactive dithiobenzoate end group has been used as a water‐soluble macromolecular chain transfer agent in the batch emulsion polymerization of styrene without any surfactant. The reaction leads to a stable latex, as a result of the in‐situ formation of an amphiphilic block copolymer stabilizer, via transfer reaction to the dithioester functions during the nucleation step. The work does not intend to apply controlled free‐radical polymerization in an aqueous dispersed system but takes advantage of the RAFT technique to create a well‐defined polyelectrolyte, with a high chain‐end reactivity.

A novel route to obtain highly ordered self-assembled honeycomb films has been investigated by a bottom-up process. A polymer with one chain end ionic functionality has been synthesized in a one-step reaction by nitroxide-mediated polymerization. This ionomer synthesis represents a very simple way, and honeycomb structured films have been observed after solvent evaporation in a long-range distance of few hundred microns in a very regular ordered arrangement. These films are simply prepared by spreading out polymers CS 2 solutions without additives over various substrates as well on inorganic surfaces as onto different polymeric substrates such as flexible PVC sheet or rigid PMMA plate. Different experimental parameters, such as polymer concentration or wet thickness, have been checked to tune the pores size and thus the honeycomb morphologies. An elegant technique based on reflected and transmitted light has been used to correlate the pores size inside and on the top of the film. This highly ordered hexagonal pattern on the polymeric surfaces suggests the possibility of taking advantage of the microtextures for inducing optical interferences but also to modify the color of this bioinspired material as a function of their visual angle as in nature.

Well‐defined glyco‐polyorganosiloxanes were synthesized by the Cu(I)‐catalyzed Huisgen 1,3‐dipolar cycloaddition reaction (often simply referred to as “click” chemistry). N‐propargylglycosylamines 2 and 4 were first synthesized from cellobiose (1) and xylogluco‐oligosaccharide XGOs 3 without protecting groups. The azide function was introduced into polydimethylsiloxanes [PDMS: 5 (MD′M) and 7 (M′DM′)] by azidolysis of the counterpart epoxy silicon with NaN3 to afford the mono‐azido 6 and di‐azido 8 derivatives, respectively. The coupling reaction took place in a hydro‐alcoholic medium in the presence of CuSO4/sodium ascorbate as catalyst. Only one compound, MD′M‐“click”‐XGO 12 showed good solubility in water with interesting surfactant properties.magnified image

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A series of diblock and comblike copolymers based on styrene and 4-vinylbenzyl chloride were synthesized by reversible addition fragmentation transfer (RAFT) using benzyl dithiobenzoate as a control agent. After quaternization of the well-defined hydrophobic precursors with triethylamine, the micellar aggregates, formed by the cationic amphiphilic diblock copolymer when dissolved in water, were investigated by static and dynamic light scattering. The spherical shape of the micelles was established in salted water. Then, the poly(styrene)-b-poly(vinylbenzyltriethylammonium chloride) cationic diblock copolymers were used as a stabilizer for the emulsion polymerization of styrene and appeared to display very good stabilization properties. The ratio between the initial number of micelles and the final number of latex particles was particularly high, as a characteristic of the high mobility of the copolymer chains. Finally, we underlined the strong influence of salt on the nucleation step of the emulsion polymerization. The influence of the architecture of the copolymers on the stabilization of latexes has also been established by using random copolymers quaternized with N,N-dimethyldodecylamine, which led to cationic comblike copolymers. They were used for the first time as stabilizers for the emulsion polymerization of styrene. These amphiphilic copolymers proved to be good stabilizers in very low proportions (0.5-1 wt% styrene), which makes them valuable due to their simple synthesis.

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