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Peripherally functionalized arborescent polystyrenes (PS) of various architectures and chain parameters (backbone DP n , number and DP n of branches, number of termini and functions) were prepared by covalently assembling different elementary building blocks of controlled DP n , synthesized using anionic and cationic polymerization techniques. These multifunctional dendritic macromolecules have narrow polydispersities (

Cyclic polystyrene-block-polyisoprenes of controlled dimensions have been synthesized for the first time by the direct coupling of α-isopropylidene-1,1-dihydroxymethyl-ω-diethylacetal-heterodifunctional linear polystyrene-block-polyisoprene precursors previously prepared by living anionic polymerization. Cyclization is achieved under high dilution by intramolecular coupling of the polymer ends under acid catalyst conditions. Using this strategy polystyrene-block-polyisoprene macrocycles of controlled chain dimensions are prepared in high yield (> 90%). Pure cycles were finally recovered by flash chromatography. The synthesis and characterization of both the linear α,ω-heterofunctional polystyrene-block-polyisoprenes block copolymers precursors and of the corresponding cyclized chain architectures are reported.

Micelles made from linear polystyrene-block-polyisoprene (PS/PI) in decane are spherical. The differences in the structure of micelles made from linear and cyclic PS/PI were investigated using small-angle X-ray scattering at rest and under shear flow. The effect of shear revealed that micelles made from cyclic copolymer chains have an elongated shape, which was confirmed by transmission electron microscopy. The cyclization of diblock copolymer chains is thus a new method to control the micellar morphology.

Functional arborescent graft polystyrenes prepared by the graft-on-graft technique, involving the iterative grafting of end functional polymer chains onto reactive polymer backbones were synthesized. The zero-generation comb polymers and then the first generation hyperbranched structures were obtained by the coupling reaction of living α-acetal polystyryllithium onto linear or comb chains of poly(chloroethyl vinyl ether) (PCEVE) of controlled DP n and structure. Both the PS grafts and the PCEVE reactive backbones were synthesized individually by living polymerization techniques. Initiation of styrene polymerization from acetal functionalized lithium derivatives yield the co-functionalization of all external polystyrene branches. Derivatization of these acetal branch termini allowed the generation of aldehyde, hydroxyl and carboxyl groups as well as the introduction of functional organic molecules at the periphery of the nanoparticles.

The recent emergence of hyperbranched polymers has opened the door for the design of a large variety of novel, well-controlled chain architectures. For instance, «comb-like» and dendritic-like polymers can be obtained from hyperbranched poly(chloroethyl vinyl ether)-g-polystyrene (PCEVE-g-PS) copolymers, with excellent control over the dimensions of the polystyrene lateral branches and the PCEVE backbone. In this work, the nanometer scale organization of these materials is studied by means of Tapping Mode Atomic Force Microscopy. We focus on the influence of the intrinsic molecular architecture of the hyperbranched PCEVE-g-PS on the organization of the material. In the case of thin deposits, we observe a layer-by-layer organization. On the free surface, it is possible to image single polymer molecules and to analyze their size in terms of polymer molecular weight. In most cases, the molecules are found to adopt an extended conformation and to form lamellar arrangements. We observe that the degree of lateral ordering of these molecules strongly depends on their intrinsic architecture.

A series of cyclic poly[(styrene)-b-(ethylene oxide)] diblock copolymers 4 (1.5 kg/mol < M n < 1.1 kg/ mol) with narrow molecular weight distributions (≤ 1.12) have been synthesized. They were obtained by intramolecular cyclization of linear α-diethyl acetal-ω-styrenyl polystyrene ethylene oxide) 3, under high dilution conditions. The use of well-defined linear precursors in association with a cyclization process based on an unimolecular end-to-end coupling reaction allows the formation of macrocyclic diblocks in high yield (more than 90%). The structural characterization and the solution behavior of both the linear and cyclic amphipathic diblock copolymers have been investigated by means of NMR, size exclusion chromatography, and viscosimetry.

The grafting of polystyryllithium onto chloroethyl ether functions of poly(chloroethyl vinyl ether) (PCEVE) chains is a selective reaction which allows the complete substitution of chloride of CEVE units by polystyrene (PS) chains. Since the PCEVE polymer backbone and the PS grafts can be prepared by living cationic and anionic polymerization, respectively, it is possible to synthesize PCEVE-g-PS polymers possessing both a backbone with controlled dimensions and an adjustable number of branches of precise length. This procedure was applied to the synthesis of a series of linear and macrocyclic comblike PCEVE-g-PS based on the use of linear and cyclic PCEVE as reactive backbone, respectively. The synthesis, the characterization and the solution properties of these linear and cyclic comblike polymers are reported.

The grafting of polystyryl lithium onto poly(chloroethyl vinyl ether) chains has been investigated. The reaction proceeds cleanly and quantitatively thus allowing the synthesis of comblike polymers Since the dimensions of the polystyrene branches and of the poly(chloroethyl vinyl ether) backbone can be controlled by living polymerizations, both the length and the number of branches of the graft copolymers can be tuned The latter behave as star polymers. The possibility to initiate a new cationic polymerization of chloroethyl vinyl ether from polystyrene branches bearing acetal termini in order to prepare the corresponding stars with poly(chloroethyl vinyl ether-b- styrene) branches is also examined. Finally access to hyperbranched polymers of controlled architecture and dimensions by deactivation of a second amount of polystyryl lithium onto the last blocks of poly(chloroethyl vinyl ether) is also reported.

The grafting reaction of polystyrene branches onto poly(chloroethyl vinyl ether) (PCEVE) chains, based on the deactivation of polystyryl (PS) carbanionic ends onto chloroethyl ether functions has been investigated. The selectivity of the coupling is very high and allows the almost complete substitution of the chloride group of the CEVE units by PS chains with molar masses up to 15 000. The main side reaction observed is the deactivation of some PS chains, at the very beginning of the reaction. It is attributed mainly to impurities present in the PCEVE solution. Since the PCEVE polymer backbone and the PS grafts can be prepared by both living cationic and anionic polymerization, it is possible to synthesize poly(CEVE-g-styrene) copolymers possessing both a backbone with controlled dimensions and an adjustable number of branches having precise length and narrow molar mass distribution. The synthesis and the characteristics of comblike poly[(chloroethyl vinyl ether)-g-styrene]s are described.

The preparation by living polymerization and the investigation of the properties of polymers with cyclic chain architectures have been recently undertaken. The cyclization involves a unimolecular end-to-end reaction of a heterodifunctional linear precursor The elementary steps of the cyclization mechanism are examined in the light of matrix-assisted laser desorption/ ionization mass spectrometry (MALDI-MS) data obtained on linear polystyrene precursors and cyclized products. The synthetic procedures developed to prepare macrocyclic polymers of various structures, as well as macrocyclic random and block copolymers are then reviewed and discussed. The main characteristics of the cyclic (co)polymers are compared to the corresponding linear chains and some of the original properties that are induced by the cyclic chain architecture are presented.

A new strategy for the synthesis of vinyl type macrocyclic polymers of controlled molecular weight and molecular weight distribution has been investigated. It involves the direct coupling of an α-ω-heterodifunctional linear polymer precursor previously prepared by living polymerization. The cyclization is achieved under high dilution, by an appropriate activation of one of the polymer-ends in order to allow its reaction with the other end function. Its application to the preparation of polystyrenes and poly(vinyl ether)s with a macrocyclic structure, as well as ring closure mechanisms in the presence of different cyclization agents are reported.

α-Halogeno ether species, in appropriate conditions, can induce the “living” cationic polymerization of vinyl ethers. They can also be used as initiators for the “living” polymerization of styrene derivatives. Therefore, their use as intermediates in the preparation of tailor-made polymers and copolymers offers interesting opportunities in macromolecular synthesis. The main parameters which determine and control their reactivity are reviewed and discussed. The possibility to generate quantitatively these derivatives by various routes and from different organic functions such as aldehyde, ketone, acetal and hydroxyl is examined. Some of these routes have been used to generate the α-halogeno ether function directly at the end of acetal and hydroxy-terminated polymers. The latter have then been used as macroinitiators to prepare new block copolymers. The synthesis of poly(isobutyl vinyl ether-β-ethyl vinyl ether), poly(styrene-β-chloroethyl vinyl ether) and poly(chloroethyl vinyl ether-β-butadiene-β-chloroethyl vinyl ether) by this technique is described.

Preparation de polymere cyclique CH 3 CH(-OR 1 -)[CH 2 CH(OR)] n CH 2 CH(OR)CH 2 -R 1 (R=CH 2 CH 2 Cl, R 1 =-(CH 2 ) 4 OCH 2 PhCH(OMe)-) par polymerisation cationique vivante du chloroethyl vinyl ether amorcee par le systeme HI/ZnCl 2 /CH 2 =CHO(CH 2 ) 4 OCHW 2 PhCH=CH 2 puis cyclisation intramoleculaire