摘要:
A method of dimerizing isocyanates including reacting the isocyanates in the presence of phosphines containing at least one directly phosphorus-attached bicyclic, cycloaliphatic radical. The polyisocyanate compositions obtained as described above can be used in mouldings, coating materials, adhesives, sealants or adjuvants that further include the polyisocyanate compositions and one or more materials selected from antioxidants, light stabilizers, pigments, fillers, additives, levelling assistance, defoamers and matting agents. The coating materials, adhesives or sealants can be used to coat substrates.
摘要:
A process for preparing polyisocyanate-modified polycarboxylic acids by conversion of anhydride-group-free polycarboxylic acids with isocyanate-functional compounds. The process includes reacting A) an anhydride-group-free polycarboxylic-acid component with B) an isocyanate-functional component having an (average) isocyanate functionality of at least 1.8, at an equivalent ratio of carboxylic acid groups to isocyanate groups of from 1.2:1 to 120:1. The polyisocyanate-modified polycarboxylic acids are solid below 40° C. and liquid above 130° C., and have an average carboxylic acid functionality of at least 1.8, a content of free carboxylic acid groups of from 4.0 wt. % to 80.0 wt. % and a content of amide groups of from 0.4 wt. % to 32.5 wt. %.
摘要:
The invention relates to new high-functional polyaddition compounds which contain free isocyanate groups with an average isocyanate functionality of 2.1 to 8.0, a concentration of uretdione of 10 to 18 wt. %, a concentration of urethane of 10 to 20 wt. % and a concentration of ester groups —CO—O and/or carbonate groups —O—CO—O of 1 to 17 wt. %, a process for the preparation thereof and their use as starting components for the preparation of polyurethane plastics, in particular as cross-linking agents for heat-curable powder coatings.
摘要:
The present invention provides an imaging element comprising on a support a photosensitive layer containing a photopolymerizable composition containing a urethane type monomer mixture according to the formula (I) as defined in the claims and description. There is further provided a method for obtaining images and/or a lithographic printing plate therewith.
摘要:
The invention relates to polyisocyanates containing allophanate groups and silane groups, to a process for preparing them and to their use as a starting component in the production of polyurethane polymers, more particularly as a crosslinker component in polyurethane paints and coatings.
摘要:
The present invention relates to polyurethane powder lacquers with optimized flow behavior, a process for their production, a process for coating substrates with these powder lacquers, as well as substrates coated with these powder lacquers.
摘要:
The invention relates to a process for the production of uretdione polyisocyanates with improved storage stability and their use as a starting component for polyurethane plastics, in particular as a crosslinker component for the production of two-component polyurethane coating compositions.
摘要:
The present invention relates to polyisocyanate mixtures prepared from aliphatic and/or cycloaliphatic diisocyanates and having a) an average isocyanate functionality of at least 2.0, b) a content of isocyanate groups (calculated as NCO; molecular weight=42) of 4.0 to 28.0 wt. % and c) a content of alkoxy groups having up to 36 carbon atoms of 2.0 to 37.5 wt. %, wherein the alkoxy groups are constituents of allophanate groups or optionally urethane groups, provided that >50 mol % of the alkoxy groups are a constituent of allophanate groups that are connected to at least two polyisocyanate molecules which are each prepared from at least two diisocyanates. The present invention also relates to a process for preparing these polyisocyanate mixtures and to coating compositions, which are highly diluted or dilutable with non-polar solvents and contain these polyisocyanate mixtures and lacquer binders or binder components optionally containing isocyanate-reactive groups.
摘要:
The novel AOX-free process for imparting wet strength to paper with water-dispersible polyisocyanates is distinguished by a good wet-strength effect, even under mild drying conditions, and does not affect the activity of optical brighteners used at the same time.
摘要:
The present invention relates to a process for the production of polyisocyanates containing uretdione groups bya) oligomerizing a portion of the isocyanate groups of diisocyanates having aliphatically and/or cycloaliphatically bound isocyanate groups in the presence of catalysts or catalyst systems which accelerate the dimerization of isocyanate groups and in the presence of trisubstituted phosphite stabilizers corresponding to formula (I) ##STR1## b) optionally termination of the oligomerization reaction at a degree of oligomerization of 10 to 60% by adding a catalyst poison andc) optionally removing unreacted diisocyanate by extraction or thin-layer distillation.The present invention also relates to the use of the resulting uretdione polyisocyanates as a starting component for polyurethane plastics, particularly as an isocyanate component for the production of uretdione hardeners for powder coating compositions.