Covestro Deutschland Ag

Covestro Intellectual Property Gmbh & Co. Kg

Yaguang Ma

Hans-Josef Laas

Hao Liu

Tian Xia

Raul Pires

Na Xu

Jinqi Li

Ling Yang

Junchao Zheng

Jianping Shen

Guoping Shi

The present invention relates to a polyether-modified polyisocyanate composition, which is obtainable by reacting a system containing the following components: a) a polyisocyanate having an isocyanate group functionality of 2-4.5; b) a polyoxyalkylene monoether alcohol; and c) optionally a catalyst; the polyoxyalkylene monoether alcohol has a number-average molecular weight of 900 g/mol-2000 g/mol and an oxypropylene group content of 45 wt. %-100 wt. %, relative to the total weight of the oxyalkylene group of the polyoxyalkylene monoether alcohol; the system has an equivalent ratio of isocyanate group to hydroxyl group of 5:1-110:1; the polyisocyanate composition has the following characteristics: i) the average isocyanate functionality is 1.8-4.1; ii) the isocyanate group content is 8-20 wt. %; and iii) the amount of the polyoxyalkylene monoether structure is greater than 10 wt. % and less than 50 wt. %, for characteristics ii) and iii), relative to the total weight of the polyisocyanate composition.

Polyether-modified polyisocyanate composition

The present invention relates to a modified polyisocyanate and use thereof, in particular as a crosslinking component of water-soluble or water-dispersible coatings. The modified polyisocyanate is obtained by a reaction of a system comprising the following components: at least an aminosulfonic acid; at least a polyisocyanate; at least a tertiary amine; and optionally a polyether alcohol containing an ethylene oxide group. The modified polyisocyanate comprises at least an iminooxadiazinedione structure and at least an isocyanurate structure, the weight ratio of the iminooxadiazinedione structure to the isocyanurate structure being 1:300 to 1:5. The amount of sulfonate group of the modified polyisocyanate is 0.75% by weight to 1.1% by weight, based on the amount of the modified polyisocyanate as 100% by weight. The viscosity thereof is 500 mPa&#xb7;s to 10000 mPa&#xb7;s, as determined according to DIN EN ISO 3219:1994-10 at a temperature of 23&#xb0; C. and a shear rate of 10 s. The coating comprising the modified polyisocyanate of the present invention can be manually stirred well, and the resulting coating layer has high gloss and good transparency.

Modified polyisocyanate

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Shanghai, China

Yaguang Ma