Abstract: Process for the preparation of impact-strengthened cast PMMA sheets comprising the following stages: 1. a mixture comprising: at least one alkoxyamine Z(-T)n, in which Z denotes a polyvalent group and n an integer greater than 2, preferably of between 2 and 10, advantageously between 2 and 8, and the monomer(s) intended to form a central block B ?is heated to a temperature sufficient to activate the alkoxyamine and polymerize the monomer(s); 2. the central block B, optionally mixed with the unconsumed monomer(s) from stage 1, is reactivated in the presence of the monomer(s) intended to form the branches A; 3. MAM and optionally at least one comonomer M which can be copolymerized by the radical route with MMA and at least one radical initiator are added to the mixture obtained in stage 2; 4. the mixture from stage 3 is cast in a mould and then heated.

Abstract: The present invention relates to a process for the preparation in aqueous solution of water-soluble acrylic polymers or for the preparation in aqueous dispersion of water-dispersible acrylic co-polymers, polymerised from, the total being 100 mol %: a) 5 to 70 mol % of one or more monomer(s) (A) which are (alkoxy)polyalkylene glycol (meth)acrylates and/or ((alkoxy)polyalkylene glycol)(meth)acrylamides; b) 5 to 95 mol % of one or more unsaturated carboxylic monomer(s) (B); and c) 0 to 85 mol % of one or more hydrophobic monomer(s) (C) which are water insoluble, in the absence of a chain-transfer agent, and in the presence of a sufficient amount of a water-soluble alkoxyamine, until a conversion of at least 90% by weight of the monomers (A), (B) and (C) is obtained. The polymer has a polydispersity index Mw/ Mn advantageously <2 and an Mn of between 10 000 g/mol and 50 000 g/mol.

Abstract: The invention concerns a process to manufacture a thermoplastic resin charged with mineral or carbonated matter, and possibly containing an organic impact modifier, through the introduction into the said resin of a comb polymer with at least one ethylenic unsaturation monomer, to which is grafted at least one polyalkylene oxide function. The resins then obtained which also form the subject of the invention have an improved impact resistance without their rigidity being degraded.

Abstract: The present invention relates to a novel process for preparing alkoxyamines from a nitroxide and a dithiocarbamate by photolysis reaction. This process, which does not generate effluent containing metals, may be carried out in batch or in continuous mode and takes place at a lower temperature than the known processes for synthesizing alkoxyamines.

Abstract: The invention relates to the use of at least one polymer containing at least one monomer selected from acrylic acid or methacrylic acid or mixtures thereof and at least one monomer which is the maleic anhydride as a dispersing and/or grinding aid agent in a fabrication process of an aqueous dispersion and/or suspension of mineral materials, wherein the molar ratio r (acrylic acid and/or methacrylic acid:(maleic anhydride) is strictly confined to the range between 2:1 and 0.1:1. Another object of the invention consists in the aqueous dispersions and suspensions of mineral materials thus produced and the use thereof in the fabrication of plastics, paper and paintworks.

Abstract: The invention relates to a polymerisable liquid mixture comprising: (a) a polymerisable thermosetting composition which is a precursor by polymerisation of a first thermoset polymer material, said composition containing at least one polythiol and/or one polyol, preferably a polythiol, and at least one polyiso(thio)cyanate; and (b) a second polymer material solubilised in the aforementioned polymerisable thermosetting composition, whereby the second material (i) contains at least one block copolymer comprising at least two polymer blocks A and B, namely an elastomer block A and a hydrophilic block B, and, following polymerisation of the polymerisable mixture, (ii) forms domains which are rich in elastomer block A and which are dispersed throughout the first material, said domains being smaller than 80 nanometers and preferably smaller than 50 nanometers.

Abstract: The invention relates to a method for preparing a living polymer comprising methacrylic and/or methacrylate units using a monofunctional or polyfunctional alkoxyamine consisting in polymerising one or several types of methacrylic an/or methacrylate units.

Abstract: The present invention relates to a process for the preparation of the alkoxyamine 2-methyl-2-[N-(diethoxy-phosphoryl-2,2-dimethylpropyl)aminoxy]propionic acid or of its salts comprising a stage of saponification of an azo compound in the presence of a base, a stage of photolysis of the salt resulting from the saponification stage in the presence of N-(tert-butyl)-1-diethylphosphono-2,2-dimethylpropyl nitroxide and optionally a stage of acidification of the salt of the alkoxyamine obtained on conclusion of the photolysis stage. The alkoxyamine or its salts can be used as radical polymerization initiators.

Abstract: The invention relates to a linear ethylenic block copolymer comprising: at least a first block A having a glass transition temperature above 20° C.; at least a second block B having a glass transition temperature below 15° C.; and at least a third block C having a glass transition temperature above 20° C.; said first block A and third block C being identical or different and at least one of them comprising at least one monomer unit comprising at least one —CO2H and/or carboxylate —COO? functional group. Use of this copolymer in adhesive compositions and thermoplastic compositions.

Abstract: The invention relates to scorch prevention and, more specifically, to a composition which comprises a nitroxide and at least one organic peroxide and which can be used to delay scorching prior to crosslinking of thermoplastic compositions and/or elastomers. The invention also relates to a crosslinkable composition and to a crosslinking method.

Abstract: The invention relates to the use of block copolymers, obtained by controlled radical polymerization in the presence of alkoxyamine derivatives of substituted nitroxides, for the production of perfectly transparent acrylic films with the mechanical properties required for the applications envisaged, whereby the transparency thereof remains under mechanical stress and a wide temperature range. The total thickness is between 40 and 300 microns, preferably 70 to 90 microns. The film has a haze of less than 2 and elongation at breakage of more than 90%.

Abstract: The present invention relates to a thermoset material with improved impact resistance comprising, by weight: •99 to 20% of a thermoset resin, •1 to 80% of an impact modifier comprising at least one copolymer chosen from copolymers comprising A-B-C and A-B blocks, in which: each block is connected to the other by means of a covalent bond or of an intermediate molecule connected to one of the blocks via a covalent bond and to the other block via another covalent bond, A is a copolymer of methyl methacrylate and of at least one water-soluble monomer, C is either (i) a PMMA (homopolymer or copolymer) this PMMA comprising optionally a water-soluble monomer or (ii) a polymer based on vinyl monomers or mixture of vinyl monomers, B is incompatible or partially compatible with the thermoset resin and incompatible with the A block and the optional C block and its glass transition temperature Tg is less than the operating temperature of the thermoset material.

Abstract: The present invention describes a composite material based on a polymer matrix in which carbon nanotubes are dispersed, and also a process for obtaining such a material. The process of the invention is based on the use, as compatibilizer, of a block copolymer obtained by controlled radical polymerization and having at least one block bearing acid and/or anhydride functions. Such a compatibilizer makes it possible to control and optimize the interfacial interactions and thus to obtain a stable composite material that has good properties for use.

Abstract: The present invention relates to the prevention of scorching before crosslinking of a thermoplastic and/or elastomeric composition with peroxides or azo compounds. This is achieved by using a family of specific nitroxides as additive.

Abstract: The invention relates to the use of alkoxyamines of formula (I): for the preparation of polymerized or non-polymerized mono- or polyalkoxyamines of formula (II):

Abstract: The present invention relates to the prevention of scorching before crosslinking of a thermoplastic and/or elastomeric composition with peroxides or azo compounds. This is achieved by using a nitroxide in combination with at least one crosslinking promoter (promoter) chosen from group (P) consisting of compounds containing at least one double bond, which may be difunctional or polyfunctional.

Abstract: The present invention relates to a process for radical emulsion, miniemulsion or microemulsion polymerization employing at least one water-soluble alkoxyamine. This process makes it possible to prepare multiblock (co)polymers, in particular diblock and triblock (co)polymers.

Abstract: The invention relates to the use of alkoxyamines of formula (I): for the preparation of polymerized or non-polymerized mono- or polyalkoxyamines of formula (II):

Abstract: The present invention is directed to a process for the preparation of polyalkoxyaminies from monoalkoxyamine(s) of formula (I) and of at least one polyunsaturated compound of formula (II): and the preparation of polyfunctional living (co)polymers by polymerization by the radical route of one or more vinyl monomers in the presence of the polyalkoxyamines thus prepared.

Abstract: The present invention describes linear or star block copolymers, their process of preparation and their use in adhesive compositions, in particular as pressure-sensitive adhesive. The copolymers of the invention are prepared by controlled radical polymerization by nitroxides; they exhibit at least one soft block with a Tg of less than 0° C. and at least one hard block with a Tg of greater than ambient temperature.