摘要:
The present invention relates to polyisocyanates which contain ester groups and havea) a content of aliphatically bound isocyanate groups of 18 to 33% by weight,b) an average NCO functionality of 4.1 to 10, preferably from 4.5 to 10, andc) a viscosity of 200 to 2,5000 mPa.s at 22.degree. C.The present invention also relates to preferred polyisocyanates which contain ester groups and havea) a content of aliphatically bound isocyanate groups of 20 to 33% by weight,b) an average NCO functionality of 5 to 8 andc) a viscosity of 500 to 1,000 mPa.s at 22.degree. C.The present invention further relates to a process for the preparation of these preferred polyisocyanates by reacting isocyanatocarboxylic acid chlorides with O-silylated, polyhydric alcohols at a temperature of about 50.degree. to 150.degree. C. Finally, the present invention relates to the use of the polyisocyanates as the isocyanate component for two-component polyurethane coating compositions.
摘要:
The present invention is directed to a process for the preparation of amines containing urethane and urea groups. The amines are produced by reacting A) isocyanate prepolymers containing urethane groups and in which the isocyanate groups are reversibly blocked with secondary monoamines with B) amines having molecular weights of from 60 to 500, which are at least difunctional and which have a total of at least two primary or secondary amino groups, with splitting off of the secondary monoamine. The invention is also directed to the amines so produced and to the use as a hardener for an epoxide resin.
摘要:
This present invention relates to a process for the preparation of O-silylated aliphatic hydroxyl, compounds by the reaction of aliphatic hydroxyl compounds with triorganochlorosilanes and removal of the resulting gaseous hydrogen chloride from the reaction mixture, characterized in that the reaction is carried out in the presence of phase transfer catalysts in the absence of solvent.The invention also relates to the use of the O-silylated hydroxyl compounds obtained by this process as starting materials for the preparation of isocyanates containing ester groups by a reaction with isocyanato carboxylic acid chlorides.
摘要:
The present invention relates to a process for the preparation of a polyurethane coating by coating a substrate with a coating composition containinga) a polyisocyanate component andb) an isocyanate-reactive component containing at least one compound corresponding to the formula ##STR1## wherein X represents an organic group which has a valency of n and is inert towards isocyanate groups at a temperature of 100.degree. C. or less,R.sup.1 and R.sup.2 may be identical or different and represent organic groups which are inert towards isocyanate groups at a temperature of 100.degree. C. or less,R.sup.3 and R.sup.4 may be identical or different and represent hydrogen or organic groups which are inert towards isocyanate groups at a temperature of 100.degree. C. or less andn represents an integer with a value of at least 2, and curing the coating composition at a temperature of 100.degree. C. or less.
摘要:
The present invention relates to a process for the preparation of a polyurethane coating by coating a substrate with a coating composition containinga) a polyisocyanate component andb) an isocyanate-reactive component containing at least one compound corresponding to the formula ##STR1## wherein X represents an organic group which has a valency of n and is inert towards isocyanate groups at a temperature of 100.degree. C. or less,R.sup.1 and R.sup.2 may be identical or different and represent organic groups which are inert towards isocyanate groups at a temperature of 100.degree. C. or less,R.sup.3 and R.sup.4 may be identical or different and represent hydrogen or organic groups which are inert towards isocyanate groups at a temperature of 100.degree. C. or less andn represents an integer with a value of at least 2,and curing the coating composition at a temperature of 100.degree. C. or less.
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:
The present invention relates to aqueous polyurethane dispersions prepared from a polyisocyanate component and one or more isocyanate-reactive compounds wherein at least 5% by weight of polyisocyanate component is a diisocyanate corresponding to formula (I) wherein R is a difunctional, C4 to C18, aliphatic, cycloaliphatic or aromatic hydrocarbon residue obtained by removing the NCO groups from an organic diisocyanate and R′ is a monofunctional, C1 to C18 hydrocarbon radical, which may contain ether oxygen atoms. The present invention also relates to the use of these PUR dispersions for coating any substrates, preferably wood substrates, such as parquet flooring.
摘要:
The present invention is directed to a process for the production of isocyanurate polyisocyanates by the partial trimerization of the isocyanate groups of aliphatic diisocyanates in the presence of catalysts which accelerate the trimerization of isocyanate groups, termination of the trimerization reaction at the particular degree of trimerization required and removal of unreacted starting diisocyanate and, optionally, other volatile constituents, characterized in that at least one diol containing ester groups and having an average molecular weight of 350 to 950 is added to the reaction mixture at any time before removal of the excess starting diisocyanate in a quantity of 1 to 50% by weight, based on the weight of the diisocyanate used as starting material, the type of reactants and the quantitative ratios between them being selected so that, on completion of the reaction, at least 10% by weight free starting diisocyanate is still present in the reaction mixture, not including any inert solvent used, and the molar ratio of isocyanurate groups to urethane groups in the end products is about 20:1 to 0.2:1.The present invention is also directed to the isocyanurate polyisocyanates obtained by this process and the use of these isocyanurate polyisocyanates, optionally blocked by blocking agents for isocyanate groups, for the production of polyurethane plastics, particularly two-component polyurethane lacquers.
摘要:
The present invention relates to polyisocyanates prepared from diphenylmethane diisocyanate wherein at least 95% of the isocyanate groups are blocked with diethyl malonate and wherein the polyisocyanates have, based on solids, A) a content of unblocked and blocked isocyanate groups (calculated as NCO) of 9% to 13%, B) a content of allophanate groups (calculated as C.sub.2 HN.sub.2 O.sub.3, molecular weight 101) of 3% to 9% and C) a calculated average functionality of 2.0 to 2.5. The present invention also relates to a process for the production of these polyisocyanates and to their use as crosslinking agents for organic polyhydroxyl compounds in polyurethane stoving lacquers.
摘要:
The present invention relates to isocyante prepolymers containing ether and ester groups, having an isocyanate content of 1.9% to 25% by weight and based on the reaction product ofA) a polyisocyanate component containing at least one organic polyisocyanate having an average molecular weight of 168 to 1000,B) an organic polyhydroxyl component containing at least one polyhydroxyl compound containing ether and ester groups, having an average hydroxyl functionality of 2 to 3 and an average hydroxyl number of 40 to 90 and based on the esterification products ofi) polyether polyols having an average hydroxyl number of 200 to 600 withii) from 25 to 67 equivalent-%, based on the hydroxyl groups of component (i) and the carboxyl groups of component (ii), of an organic carboxylic acid component containing at least one organic monocarboxylic acid or a mixture of at least one organic monocarboxylic acid with up to 20 carboxyl equivalent-%, based on all the carboxylic acids, of polybasic organic carboxylic acids.The present invention also relates to a process for the preparation of these isocyanate prepolymers containing ether and ester groups and to their as binders or binding components in low solvent or solvent-free polyurethane coating compositions, sealing compositions or casting compositions.