Abstract: The invention relates to a composition and a method of preparing one such composition and an isocyanatoalkoxysilane; the polyisocyanate composition contains at least two different oligomeric compounds comprising at least three units and at most five units selected from aminoalkylsilane units and diamine units and at least one function selected from isocyanate functions and from those derived therefrom, the aforementioned compounds having at least two aminoalkylsilane units and another compound having at least two diamine units; the invention is suitable for coatings.

Abstract: A method is described of preparing (poly)isocyanurate polyisocyanates by catalytic cyclotrimerization of isocyanates. A catalytic system is used which includes a cyclotrimerization catalyst based on a quatemary ammonium salt and imidazole as a cocatalyst.

Abstract: This invention relates to the use as catalyst for the cyclotrimerization reaction of isocyanates of a hydrogencarbonate of a cation which either as it is or in the form complexed with a complexing agent has an average molecular or ionic radius of more than 1 ?, preferably greater than 1.5 ?, and which is at least partially soluble in the reaction medium. The invention also relates to a method of preparing (poly)isocyanurate polyisocyanates by catalytic cyclotrimerization of isocyanates, in which a catalytic system is used which comprises a cyclotrimerization catalyst based on a quaternary ammonium salt as catalyst and imidazole as cocatalyst.

Abstract: This invention relates to a process for the preparation of aqueous emulsions of blocked (poly)isocyanates, this process comprising the steps consisting successively in: a) placing an isocyanate composition containing free isocyanate functions in contact with at least one blocking agent A in the presence of a surfactant B and an aqueous phase, the said isocyanate composition being added gradually to a stock containing at least some of the aqueous phase and at least some of the blocking agent; and optionally, b) subjecting the mixture obtained to a shear (speed gradient) of greater than 1000 s?1, preferably greater than 20,000 s?1 and less than 1,000,000 s?1, preferably less than 200,000 s?1, and c) repeating step b), optionally after step a) has been repeated, until a stable emulsion is obtained whose particles have a Sauter diameter of greater than 0.1 ?m, preferably 0.2 ?m, and less than 5 ?m, preferably less than 2 ?m, and a dispersion width of less than 5 ?m.

Abstract: A low viscosity polyisocyanate composition containing at least one isocyanate dimer having a uretidinedione unit is prepared from a reaction medium containing at least one isocyanate monomer in which the isocyanate groups are borne by sp3 carbon atoms. The reaction medium is heated, in the absence of a dimerization catalyst, to a temperature of at least 50° C. and not more than 200° C. for a period of not more than 24 hours.

Abstract: The invention concerns a (cyclo)trimerisation method for isocyanates having at least two isocyanate functions, characterised in that it comprises: a) reacting initial isocyanate monomers having at least two isocyanate functions, optionally in the presence of other monomers reactive with the isocyanate monomers having at least two isocyanate functions at a temperature of at least 20° C., advantageously at least 50° C., and lower than 200° C., advantageously lower than 150° C., in the presence of a compound comprising at least one rare earth alcoholate function; b) stopping the reaction by inactivating the catalyst or its derivative forms in the reaction medium at a transformation rate of at least 2.5% and at most 90% of the initial isocyanate functions; and optionally c) distilling the reaction medium to eliminate the unreacted monomers.

Abstract: The invention concerns a method for cyclotrimerization of isocyanate functions by action of a catalyst based on quaternary ammonium or phosphonium. The invention is characterised in that said isocyanate functions are branched and said onium ions are selected among those whereof the total amount of carbons is not more than 30 and not less than 12; and whereof the counterion is selected among the anions corresponding to weak acids whereof the pKA is not less than 8, preferably not less than 10, more preferably not less than 12, whereof the substituents are aliphatic compounds and do not have an unsaturation in beta; and said onium ions comprise at least 2 radicals of more than 6, advantageously more than 10, preferably more than 12 carbon atoms.

Abstract: This invention relates to the use as catalyst for the cyclotrimerization reaction of isocyanates of a hydrogencarbonate of a cation which either as it is or in the form complexed with a complexing agent has an average molecular or ionic radius of more than 1 Å, preferably greater than 1.5 Å, and which is at least partially soluble in the reaction medium. The invention also relates to a method of preparing (poly)isocyanurate polyisocyanates by catalytic cyclotrimerization of isocyanates, in which a catalytic system is used which comprises a cyclotrimerization catalyst based on a quaternary ammonium salt as catalyst and imidazole as cocatalyst.

Abstract: This invention relates to a process for the preparation of aqueous emulsions of blocked (poly)isocyanates, this process comprising the steps consisting successively in:

Abstract: The invention concerns a method for cyclotrimerization of isocyanate functions by action of a catalyst based on quaternary ammonium or phosphonium. The invention is characterised in that said isocyanate functions are branched and said onium ions are selected among those whereof the total amount of carbons is not more than 30 and not less than 12; and whereof the counterion is selected among the anions corresponding to weak acids whereof the pKA is not less than 8, preferably not less than 10, more preferably not less than 12, whereof the substituents are aliphatic compounds and do not have an insaturation in beta; and said onium ions comprise at least 2 radicals of more than 6, advantageously more than 10, preferably more than 12 carbon atoms.

Abstract: This invention relates to a process for separating one (or more) oligomeric or polymeric compound(s) (A) obtained by polymerization of isocyanate monomers (A1) or copolymerization of isocyanate monomers with another polymerizable compound (A2), in particular a polyol, the said compound(s) A having a viscosity (a), from the unconverted monomer(s), this process comprising addition to the said compound(s) (A) of one (or more) compound(s) (B) consisting of the product of polymerization of isocyanate monomers (B1) or of copolymerization of isocyanate monomers with another polymerizable compound (B2), in particular a polyol, the said compound(s) (B) having a viscosity (b) and the ratio of the viscosities b/a being less than 1/1.5, preferably less than 1/2, and co-distillation of (A) and (B), in order to separate the compound(s) (A) from the corresponding unconverted monomers.

Abstract: A method for obtaining substantially pure toluylene 2,6-diisocyanate from a mixture of the 2,4 and 2,6 isomers of toluylene diisocyanate, wherein at least one crystallizing-melting cycle is performed on the mixture of said isomers to separate out the toluylene 2,6 diisocyanate isomer. In an alternative embodiment, the mixture is contacted, prior to the crystallizing-melting cycle, with a compound or catalyst capable of converting part of the toluene 2,4-diisocyanate isomer therein, and the reacted 2,4 isomer is separated. Said method is advantageous in that usable by-products are produced.

Abstract: Aromatic polyisocyanates are prepared by reacting at least one compound (A), containing at least two primary amine functions and at least one aromatic nucleus, with a relatively modest quantity of phosgene, in the gaseous phase, the amount of phosgene ranging from the stoichiometric amount to a stoichiometric excess of 100% with respect to the number of moles of amine functions of compound (A), carried out in a mixed reactor which comprises a first, homogenizing zone constituting from 20% to 80% of the total volume thereof, and a second, essentially piston flow downstream zone constituting from 80% to 20% of the total volume thereof.

Abstract: Aromatic polyisocyanates, e.g., toluene diisocyanate, are prepared by reacting/contacting at least one aromatic compound (A) bearing at least two primary amine substituents, e.g., toluenediamine, xylylenediamine and/or phenylenediamine,, with phosgene, in gaseous phase and in a reactor/reaction zone devoid of active mechanical stirring.