摘要:
Isocyanate prepolymers based on an aromatic diisocyanate and a polyether polyol in which at least 95% of the isocyanate groups are blocked by blocking agents selected fromA) about 50 to about 97 equivalent % of a phenol or substituted phenol,B) about 30 to about 50 equivalent % of a pyrazole or a substituted pyrazole andC) 0 to about 10 equivalent % of a blocking agent different from A) and B).These blocked isocyanate prepolymers are particularly useful for the production of flexible epoxy resin systems.
摘要:
The present invention relates to compounds containing alkoxysilane and hydantoin groups and corresponding to the formula ##STR1## wherein X represents identical or different organic groups which are inert to isocyanate groups below 100.degree. C., provided that at least one of these groups is an alkoxy group, Z represents COOR.sub.1 or an aromatic ring, R represents the residue obtained by removing the isocyanate groups from an organic monomeric polyisocyanate, a polyisocyanate adduct or an NCO prepolymer, R.sub.1 represents an organic group which is inert to isocyanate groups at a temperature of 100.degree. C. or less, R.sub.3 and R.sub.4 are identical or different and represent hydrogen or organic groups which are inert to isocyanate groups at a temperature of 100.degree. C. or less, n is an integer from 1 to 8 and m has an average value of 1.5 to 6. The present invention also relates to the use of these compounds for the preparation coatings, sealants and adhesives.
摘要:
Isocyanate prepolymers having an NCO content of 1.5 to 5.0 wt. % and a monomeric diisocyanate content of less than 0.5 wt. % which are the reaction products ofA) aromatic or cycloaliphatic diisocyanates withB) mixtures ofB1) polyether polyols having a molecular weight of 1000 to 3000 andB2) polyester carbonate diols having a molecular weight of 700 to 3000,wherein components B1) and B2) are present in a weight ratio of 0.25:1 to 1.5:1;a process for the preparation of these isocyanate prepolymers by reacting the preceding starting materials at an NCO/OH equivalent ratio of at least 1.5:1 and optionally with subsequent removing unreacted monomeric diisocyanate by distillation; and the use of these isocyanate prepolymers as binders for sealing or coating compositions.
摘要:
The invention relates to soluble organic-inorganic compositions comprising linear and cyclic hydrosiloxanes, to a novel process for preparing them and to their use as coating materials.
摘要:
The present invention relates to compounds which are substantially free from isocyanate groups, have an alkoxysilane group content (calculated as Si, MW 28) of 1 to 6% by weight, based on the weight of the compounds, and containing sufficient chemically incorporated hydrophilic groups to form a stable dispersion with water, wherein the alkoxysilane groups are incorporated as the reaction products ofa) a polyisocyanate component having a minimum average functionality of 2.4 and containing at least 50% by weight of polyisocyanate adducts andb) compounds containing secondary amino groups and alkoxysilane groups.The present invention also relates to the use of these compounds for the preparation of coatings, sealants and adhesives.
摘要:
The present invention relates to aqueous dispersions which containA) 30 to 90% by weight, based on the solids content of A) and B), of polyurethane/ureas containing 0.5 to 6% by weight, based on the weight of the polyurethane/ureas, of alkoxysilane groups (calculated as Si, MW 28) andB) 10 to 70% by weight, based on the solids content of A) and B), of colloidal silica.The present invention relates to coatings prepared from these aqueous dispersions.
摘要:
The present invention relates to a binder composition containing a) 30 to 90 wt. % of an aqueous, hydroxy- and/or amino-functional resin dispersion and b) 10 to 70 wt. % of a curing agent containing alkoxysilyl groups and having a free isocyanate group content of 10 to 23 wt. % and a viscosity of 50 to 10000 mPa.multidot.s at 23.degree. C., wherein the molar ratio of the hydroxyl groups of component a) to the isocyanate groups of component b) is 0.5:1 to 2:1. The present invention also relates to the use of these binder compositions in coating and sealing compositions.
摘要:
The present invention relates to a process for preparing polyisocyanates containing allophanate groups by reacting compounds a), which i) contain urethane groups, but which are substantially free of hydroxyl groups and isocyanate groups, ii) have an average of at least two urethane groups per molecule, iii) are prepared by reacting organic isocyanates a1) with organic hydroxyl compounds a2) and iv) have an average molecular weight of at most 2,500, with excess quantities, based on the urethane groups, of distillable organic polyisocyanates b) to form polyisocyanates containing allophanate groups and subsequently removing by distillation the unreacted excess of component b) to a residual content of less than 0.5 wt. %, provided that polyisocyanates a1) and polyisocyanates b) are different. The present invention also relates to the products obtained from this process and to their use as binders or binder components in coating compositions.
摘要:
Water-dispersible polyisocyanate compositions based on aliphatic and aromatic diisocyanates and having an NCO content, based on solids, of 6 to 21% by weight, a weight ratio of incorporated TDI units to incorporated HDI units of 6:1 to 0.1:1 and a content of ethylene oxide units, arranged within terminal polyether chains, of 5 to 40% by weight; a method for the preparation of these polyisocyanate compositions by reacting a polyisocyanate component with monovalent polyether alcohols containing ethylene oxide units at an NCO/OH equivalent ratio of 2:1 to 120:1; and aqueous coating compositions containing these polyisocyanate compositions and polyhydroxyl compounds as the binder.
摘要:
The present invention relates to olefinically unsaturated, urethane group-containing isocyanates which are prepared by reacting at an NCO/OH equivalent ratio of 4 to 40a) an isocyanate component substantially containing urethane group-free cycloaliphatic diisocyanates withb) an unsaturated alcohol component substantially containing monohydric olefinically unsaturated alcoholsand subsequently removing distillable unreacted isocyanates by distillation. The present invention also relates to a process for the preparation of these isocyanates and to their use as a binder component in one-component, coating compositions which may be cured at room temperature.