摘要:
This process is characterized by the fact that at least one of the said monomers is polymerized or copolymerized in bulk, solution, emulsion or suspension, at a temperature that can be as low as 0.degree. C., in the presence of an initiation system including: at least one compound generating radicals, other than bromofluorene, and at least one catalyst consisting of a complex of palladium in the 0 oxidation state, denoted by the following formula (I): Pd(0)L.sup.1 L.sup.2 L.sup.3 L.sup.4 in which each of L.sup.1, L.sup.2, L.sup.3 and L.sup.4, which are identical or different, denotes a ligand which may be a chiral ligand, which is chosen from PRR'R", P(OR)(OR')(OR"), NRR'R", ORR', SRR', SeRR', AsRR'R", SbRR'R", where each of R, R' and R" independently denotes a C.sub.1 -C.sub.14 alkyl group, optionally substituted, or an optionally substituted aromatic group, it being possible for at least two of these ligands to be joined to one another by one or more divalent radicals.
摘要:
This process is characterized in that at least one of the said monomers is polymerized or copolymerized in bulk, solution, emulsion or suspension, at a temperature which may be as low as 0.degree. C., in the presence of an initiator system comprising at least one non-peroxy radical-generator compound and at least one catalyst consisting of a metal complex represented by formula Ma.sub.a (L).sub.n in which M represents Rh, Co or Ir; A represents, a halogen or a pseudohalogen; the groups L, which may be identical or different, each represent a ligand which may be a chiral ligand, which is chosen from cyclooctadiene, PRR'R", P(OR) (OR') (OR"), NRR'R", ORR', SRR', SeRR', AsRR'R", SbRR'R", each radical R, R' and R" independently representing an optionally substituted C.sub.1 -C.sub.14 alkyl group or an optionally substituted aromatic group, it being possible for at least two of these ligands to be joined together by one or more divalent radicals; a is an integer such that 1.ltoreq.a.ltoreq.3 ; n is an integer such that 1.ltoreq.n.ltoreq.5, and in the absence of activator.
摘要:
The invention relates to a method for obtaining polyamide or copolyamide particles which are spheroidal and whose average diameter is between 40 and 150 μm, preferably between 60 and 100 μm. Said method consists of introducing a mineral charge, preferably silica, having an average diameter of 1-30 μm into the reaction mixture. The invention also relates to a polyamide or copolyester amide powder and to the use thereof in order to manufacture coatings, ink compositions, paint compositions, cosmetic compositions, pharmaceutical compositions, alloys with metal powders or metal oxide powders and parts by agglomerating said powder by laser sintering, IR radiation or UV radiation.
摘要:
Polymers are obtained by a radical (co)polymerization of ethylene under high pressure in the presence of at least one initiating free radical (Z*) and of at least one controlling stable free radical (SFR*) which comprises the indoline nitroxide backbone represented by the formula (I). A is a hydrocarbonaceous chain forming an aromatic ring with the two carbon atoms to which it is attached, this ring being able to carry substituents or being able to carry one or more rings placed side by side, which rings are aromatic or aliphatic and optionally substituted, the carbon atoms forming the nitrogenous ring and in the alpha- and beta-position with respect to the nitrogen atom being, able to carry hydrogen atoms or substituents.
摘要:
A radical (co)polymerization of ethylene is carried out under high pressure in the presence of at least one initiating free radical (Z•) and of at least one controlling stable free radical (SFR•) which comprises the indoline nitroxide backbone represented by the formula (I). A is a hydrocarbonaceous chain forming an aromatic ring with the two carbon atoms to which it is attached, this ring being able to carry substituents or being able to carry one or more rings placed side by side, which rings are aromatic or aliphatic and optionally substituted, the carbon atoms forming the nitrogenous ring and in the alpha- and beta-position with respect to the nitrogen atom being able to carry hydrogen atoms or substituents.
摘要:
The invention provides a method comprising contacting, between 100° C. and 230° C. and under agitation, an elastomer, a functionalising agent and optionally, a peroxide compound. The functionalising agent is a thiolcarboxylic acid polyester or a reaction product of a thiolcarboxylic acid or ester with ethylene sulphide. The functionalised elastomer can also be pre-formed, then incorporated into the bitumen. The resulting compositions are usable directly or after dilution, for forming bituminous binders to produce surfacing, coating and waterproofing materials.
摘要:
The invention relates to a process for trapping a free monomer which has not reacted by copolymerization or by grafting comprising at least one epoxide functional group in a thermoplastic composition based on ethylene and/or on propylene and based on at least one monomer comprising at least one epoxide functional group, the said process comprising the following stages: preparation of the said thermoplastic composition, addition of a sufficient amount of a solid trapping additive exhibiting, at its surface, sites with a basic nature within the Lewis or Brönsted meaning. The trapping additive is a porous zeolite, the diameter of the pores of which is between 5 and 15 angströms, preferably between 6 and 13 angströms. The invention also relates to the composition obtained by such a process and to the blends comprising such a composition.
摘要:
The invention relates to a continuous process for the manufacture of PVDF homopolymer or copolymer. The optional comonomer comprises a vinyl group polymerized by free radicals, and comprises at least one fluorine atom, a fluoroalkyl group or a fluoroalkoxy group, directly attached to this vinyl group. The invention also relates to PVDF homopolymers made by processes of the invention. The invention further relates to a process for deoxygenating a flow.
摘要:
The invention relates to a process for trapping a free monomer which has not reacted by copolymerization or by grafting comprising at least one epoxide functional group in a thermoplastic composition based on ethylene and/or on propylene and based on at least one monomer comprising at least one epoxide functional group, the said process comprising the following stages:preparation of the said thermoplastic composition,addition of a sufficient amount of a solid trapping additive exhibiting, at its surface, sites with a basic nature within the Lewis or Brönsted meaning.The trapping additive is a porous zeolite, the diameter of the pores of which is between 5 and 15 angströms, preferably between 6 and 13 angströms. The invention also relates to the composition obtained by such a process and to the blends comprising such a composition.
摘要:
For trapping a residual monomer containing an expoxide function that has not reacted by copolymerization or by grafting, in a thermoplastic composition based on a copolymer of ethylene and/or propylene, a sufficient amount of an acidic trapping additive is added to remove the residual monomer. The trapping additive is preferably a porous zeolite with a pore diameter of between 2 and 10 angstroms. Improved compositions and blends are thereby obtained.