摘要:
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):
摘要:
The present invention relates to a process for the preparation of β-phosphorated nitroxide radicals which consist in preparing, in a first step, an aminophosphonate by reaction of a carbonyl compound, of a primary amine and of a phosphorous compound in the presence of a Lewis acid and then, in a second step, in oxidizing the said crude aminophosphonate using nonhalogenated organic peracids in a water/organic solvent two-phase medium with an aqueous phase buffered at a pH ranging from 5 to 12.
摘要:
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, 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 {overscore (Mw)}/{overscore (Mn)} advantageously 50%) is converted by the alkoxyamine and the polymerization is completed by a conventional radical initiator. The polymer obtained has a polydispersity index {overscore (Mw)}/{overscore (Mn)}
摘要:
The invention relates to the production and use of block copolymers which are obtained by means of controlled radical polymerisation in the presence of nitroxides for the purpose of reinforcing fragile polymer matrices. The invention offers advantages such as (i) simplicity of copolymer synthesis and use and (ii) fine dispersion of the copolymer molecules in the fragile matrix, which ensures both the transparency of the material and high reinforcement against impact. More specifically, the invention relates to the radical synthesis of block copolymers comprising at least three blocks, which include one block having a glass transition temperature of less than 0° C. and a thermoplastic end block having a glass transition temperature of more than 0° C., thereby guaranteeing compatibility with the fragile matrix to be reinforced against impact.
摘要:
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.
摘要:
The present invention is directed to a process for the preparation of polyalkoxyaminies from monioalkoxyamine(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.
摘要:
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. The invention also relates to the use of these impact modifiers in thermosets.
摘要:
The present invention relates to a linear ethylenic block copolymer comprising in each block at least one ionic hydrophilic unit, which may be different from one block to another, the said ionic hydrophilic unit being present in each block in a proportion of from 2% to 100% by weight relative to the weight of the said block.The invention also relates to a cosmetic or pharmaceutical composition comprising such a copolymer, and also to a cosmetic process for making up or caring for keratin materials using the said composition.
摘要:
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%.
摘要:
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.