A process for the preparation of polysocyanates containing...

C - Chemistry – Metallurgy – 08 – G

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

402/159, 260/248

C08G 18/79 (2006.01) C07D 229/00 (2006.01) C07D 251/34 (2006.01) C09D 175/12 (2006.01)

Patent

CA 2006797

The present invention is directed to a process for the preparation of modified polyisocyanates containing uretdione and isocyanurate groups by the oligomerization of a portion of the isocyanate groups of organic diisocyanates containing (cyclo)aliphatically-bound isocyanate groups in the presence of organic phosphines of catalysts followed by termination of the oligomerization reaction at the desired degree of oligomerization by the addition of a catalyst poison and removal, by distillation, of at least a portion of the excess, unreacted starting diisocyanate, characterized in that a) about 0.1 to 10% of the isocyanate groups present in the starting diisocyanate are converted into urethane groups by the addition of at least one alcohol before and/or during the oligomerization reaction, and b) the distillation residue obtained after removal of the excess starting diisocyanate is heated to temperatures of at least 50°C in the presence of 100 to 10,000 ppm, based on the weight of the distillation residue, of a peroxide. The present invention is also directed to the polyisocyanates containing uretdione and isocyanurate groups obtained by this process and their use, optionally in blocked form, as the isocyanate component in two-component polyurethane coatings.

L'invention en question concerne un procédé de préparation de polyisocyanates modifiés contenant des groupes uretdiones et isocyanurates par l'oligomérisation d'une partie des groupes isocyanates de diisocyanates organiques contenant des groupes isocyanates reliés à la région (cyclo)aliphatique, en présence de phosphines organiques de catalyseurs, suivie de la terminaison de l'oligomérisation au degré désiré d'oligomérisation en ajoutant un catalyseur empoisonné et de l'extraction par distillation d'au moins une partie de l'excès du diisocyanate de départ qui n'a pas réagi. Le procédé comporte les caractéristiques suivantes : a) environ 0,1 à 10 % des groupes isocyanates présents dans le diisocyanate de départ sont convertis en groupes uréthanes par addition d'au moins un groupe alcool avant et/ou durant la réaction d'oligomérisation et b) le résidu de distillation obtenu après l'extraction de l'excès de diisocyanate de départ est chauffé à des températures d'au moins 50 degrés C en présence de 100 à 10 000 ppm (en se basant sur le poids du résidu de distillation) d'un peroxyde. L'invention en question concerne aussi les polyisocyanates contenant des groupes uretdiones et isocyanurates obtenus par ce procédé et leur utilisation, facultativement sous forme de polymères séquencés, comme composant isocyanate dans les revêtements de polyuréthanes à deux composants.

LandOfFree

Say what you really think

Search LandOfFree.com for Canadian inventors and patents. Rate them and share your experience with other people.

Rating

A process for the preparation of polysocyanates containing... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with A process for the preparation of polysocyanates containing..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A process for the preparation of polysocyanates containing... will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFCA-PAI-O-1777231

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.