Elf Atochem S.a.

Atochem

Societe Chimique Des Charbonnages S.a.

Norsolor

Sunil K Varshney

Philippe Teyssie

Roger Fayt

Bruno Vuillemin

Philippe Heim

Robert Jerome

Philippe Bayard

Christian Jacobs

Patrice Gaillard

Yves Barbier

Jean-Paul Hautekeer

A process for manufacturing a star shaped block polymer of formula (PA--PB--PC).sub.n --N--(PD--PE).sub.m wherein PA, PB and PC are respectively vinylaromatic/methacrylic blocks, acrylic blocks and methacrylic blocks. PD is a polymer block selected from vinylaromatic and/or methacrylic monomer units, PE is an acrylic polymer block, n is 2 to 20 and m is 0 to 18 with the proviso that m+n is .ltoreq.20. The process proceeds by anionic polymerization in the presence of a monofunctional initiator of formula (II),

Star-shaped copolymers and process for their manufacture

This invention relates to an initiating system for the anionic polymerization of acrylic monomers, and where necessary vinyl comonomers, including at least one R-M initiator in which M is a metal chosen from among the alkali and alkaline earth metals and R is a linear or branched chain alkyl, aryl, or arylalkyl radical. The polymerization may also take place in the presence of at least one R.sub.1 OM.sub.1 alkali metal alcoholate, in which R is an linear or branched chain alkyl, aryl, or arylalkyl radical and M.sub.1 is an alkali metal, on the condition that when M.sub.1 is lithium, then R is an aryl or arylalkyl radical. This invention also related to a process for the polymerization of primary, secondary, or tertiary alkyl acrylates, and possibly of vinyl comonomers, in the presence of the initiating system described above.

Initiating process and system for the anionic polymerisation of acrylic

An initiation system for the anionic polymerization of (meth)acrylic monomers and, optionally, nonacrylic vinyl monomers is disclosed. The initiation system comprises (1) a functional initiator and (2) an alkali metal alcoholate having the formula R'OM', in which M' is an alkali metal and R' is a group R.sup.1 (OR.sup.2).sub.m where R.sup.1 is a C.sub.1 -C.sub.6 alkyl or arylalkyl radical, R.sup.2 is a C.sub.2 -C.sub.4 alkylene radical and m is equal to 1, 2 or 3. The initiation system is applied to the formation of (meth)acrylic homopolymers and block copolymers of (meth)acrylic monomers and, optionally, nonacrylic vinyl comonomers.

Initiation system for the anionic polymerisation of (meth)acrylic

A diblock copolymer obtained by polymerizing acrylic, methacrylic or nonacrylic vinyl monomers in the presence of a polymerization initiating amount of an initiation system including (1) at least one functional initiator and (2) an alkali metal alcoholate. The alcoholate has the formula:

Initiation system for the anionic polymerization of (meth)acrylic

Novel N-substituted maleimide homopolymers having a number-average molecular weight ranging from 12,000 to about 100,000 are prepared by anionically polymerizing an N-substituted maleimide monomer, in solvent phase, in the presence of at least one organometallic polymerization initiator which comprises sec-butyllithium, a sodium alcoholate, diphenylmethylpotassium, naphthalenelithium or naphthalenesodium, and novel N-substituted maleimide homopolymers having a polydispersity index ranging from 1.1 to 1.5 are prepared by anionically polymerizing an N-substituted maleimide monomer, in solvent phase, in the presence of at least one alkali metal organometallic polymerization initiator and at least one inorganic or organic salt of an alkali or alkaline earth metal; novel block copolymers include blocks of the above maleimido homopolymers and, e.g., blocks of an acrylic or methacrylic polymer.

Heat-resistant maleimido polymers/block copolymers

The initiating system for the anionic polymerization of acrylic monomers, and where necessary, vinyl comonomers, including at least one R-M initiator in which M=a metal chosen from among the alkaline and alcaline earth metals and R=an alkyl with a linear or branched chain at C.sub.2 -C.sub.6 or aryl or arylalkyl, is characterized by the fact that the polymerization takes place in the presence also of at least one R.sub.1 OM.sub.1 alkaline metal alcoholate, in which R=an alkyl with a linear or branched chain at C.sub.1 -C.sub.6 or aryl or aryalkyl and M.sub.1 =an alkaline metal, on condition that when M.sub.1 is lithium, then R=an aryl or arylalkyl. Said process for the polymerization of primary, secondary, or tertiary alkyl acrylates, and possibly of vinyl comonomers, is characterized by the fact that the polymerization takes place in the presence of an initiating system as described above.

Initiating process and system for the anionic polymerization of acrylic

Functionalized multiblock macromonomers and process for their production

Method and system for priming anionic polymerization of (meth)acrylates

Acrylic triblock copolymers, their preparation and their application to

A process for the polymerization of acrylic monomers and optionally of vinyl comonomers using (i) an initiator of formula (I):

Growing community of inventors

Liege, Belgium

Sunil K Varshney