Abstract:
The invention relates to the use of specific pyridines as catalysts for the dimerization of isocyanates (uretdione formation) and a process for preparing polyisocyanates having a high content of uretdione groups.
Abstract:
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.
Abstract:
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. %.
Abstract:
Polyaddition compounds containing uretdione groups prepared by reacting uretdione polyisocyanates formed from diisocyanates having exclusively secondary- and/or tertiary-attached isocyanate groups with a molar fraction of isocyanurate structures, based on the sum of uretdione groups and isocyanurate groups, of not more than 10%, with compounds reactive towards isocyanates. The polyaddition compounds can be use as a starting component in the preparation of polyurethane plastics, in particular as crosslinkers for heat-crosslinkable powder coating materials. The compounds may be used as starting components in the preparation of moldings and shaped parts, and as starting components in the preparation of coating materials and coatings.
Abstract:
Biuret group-containing polyisocyanates are produced having an isocyanate functionality of at least 4 are prepared by reacting polyisocyanates having a functionality of at least 2.8 with water as the biuretizing agent. Most preferably water is used as the sole biuretizing agent. The preparation is useful as a curing agent in crosslinkable coating compositions. The coating composition can be used as an automotive clearcoat over a conventional pigmented basecoat, or as a basecoat or monocoat or even as a primer or sealer when a suitable amount of pigment is incorporated therein.
Abstract:
The present invention relates to a modified polyisocyanate which is the reaction product of a polyisocyanate with 2-(cyclohexylamino)-ethanesulfonic acid and/or 3-(cyclohexylamino)-propanesulfonic acid, to a process for preparing these modified polyisocyanates, to coating compositions containing these modified polyisocyanates and to coated substrates prepared from these coating compositions.
Abstract:
The present invention relates to an improved process for the continuous preparation of polyisocyanates with a biuret structure comprising the steps of continuously reacting excess amounts of organic diisocyanates having exclusively aliphatically and/or cycloaliphatically bound isocyanate groups with organic diamines having exclusively aliphatically and/or cycloaliphatically bound primary amino groups at temperatures above 170° C. and adding acid before or during the reaction.
Abstract:
The present invention relates to polyaddition compounds, which are solid below 40° C. and liquid above 125° C., are prepared by the reaction of an isocyanate component containing uretdione groups with a polyol containing ester and/or carbonate groups, other than hydroxypivalic acid neopentylglycol ester, and have a) an average isocyanate functionality of 2.0 to 8.0 and a content of free isocyanate groups (calculated as NCO; molecular weight=42) of 2.1 to 6.0 wt. %, b) a content of uretdione groups (calculated as C2N2O2; molecular weight=84) of 10 to 19 wt. %, c) a content of urethane groups (calculated as —NH—CO—O; molecular weight=59) of 10 to 17 wt. % and d) a content of ester groups —CO—O (calculated as —CO—O; molecular weight=44) and/or carbonate groups —O—CO—O (calculated as —CO—O; molecular weight=44) of 1 to 17 wt. %. The present invention also relates to a process for the preparation of these polyaddition compounds to two-component polyurethane powder coating compositions containing these polyaddition compounds as the crosslinking agent and isocyanate-reactive compounds as the binder.
Abstract translation:本发明涉及通过含有脲二酮基团的异氰酸酯组分与含有多羟基酯和/或碳酸酯基团的异氰酸酯组分(羟基新戊酸新戊二醇)反应来制备固体低于40℃的加氢化合物和高于125℃的液体 酯和hasa)的平均异氰酸酯官能度为2.0至8.0,游离异氰酸酯基团的含量(以NCO计算;分子量= 42)为2.1至6.0重量%。 %,b)脲二酮基团的含量(以C 2 N 2 O 2计算;分子量= 84)为10〜19重量%。 %,c)氨基甲酸酯基团的含量(以-NH-CO-O计算;分子量= 59)为10〜17重量%。 %和d)酯基-CO-O(以-CO-O计算;分子量= 44)和/或碳酸酯基团-O-CO-O(以-CO-O计算;分子量= 44)的含量为 1至17wt。 %。 本发明还涉及将这些加聚化合物制备成双组分聚氨酯粉末涂料组合物的方法,该组合物含有这些加聚化合物作为交联剂和异氰酸酯反应性化合物作为粘合剂
Abstract:
The present invention relates to coating compositions containing 40 to 100% by weight, based on resin solids, of an alkoxysilyl-functional polyisocyanate polyurea which is reaction product of A) a polyisocyanate component having an average functionality of 2.5 to 5.5, an NCO content of 11.0 to 20.0% by weight and a monomeric diisocyanate content of less than 10% by weight, and containing at least 50% by weight of a polyisocyanate prepared from 4,4′-diisocyanatodicyclohexyl-methane with B) at least 0.7 equivalents, based on the equivalents of isocyanate groups, of an aminosilane corresponding to formula (I) (RO)nY(3−n)Si—CH2CH2CH2—NHZ (I), wherein R represents methyl or ethyl, Y represents methyl, Z represents H, a C1-C12 alkyl or CH2CH2CH2—Si(OR)nY3−n, and n is 1, 2 or 3, and C) optionally other isocyanate-reactive compounds. The present invention also relates the hydrolyzates/condensates that are prepared by adding water or an aqueous solution of a catalyst to the coating compositions according to the invention.
Abstract:
The invention relates to the use of 4-isocyanatomethyloctane 1,8-diisocyanate isocyanatononane, (TIN) and TIN-containing mixtures for preparing polyurethane lacquers and coatings which can be applied from an aqueous medium.