摘要:
Impregnating agents are provided consisting essentially of(a) an NCO-prepolymer or NCO-semi-prepolymer which is curable by atmospheric moisture, with an NCO content of 2 to 25% by weight, based on(a1) an organic polyisocyanate and(a2) a compound with at least 2 alcohol hydroxyl groups,(b) a solvent which is inert with respect to isocyanate groups in which the (a1) organic polyisocyanate is a polyisocyanate with exclusively aliphatically or cycloaliphatically bound isocyanate groups and the (a2) polyhydroxyl compound is a polysiloxane of the molecular weight range of 300 to 5000 which has at least 2 alcoholically bound hydroxyl groups.A method of impregnating mineral substrates with such impregnating agents is also provided.
摘要:
Impregnating agents are provided consisting essentially of(a) an NCO-prepolymer or NCO-semi-prepolymer which is curable by atmospheric moisture, with an NCO content of 2 to 25% by weight, based on(a1) an organic polyisocyanateand(a2) a compound with at least 2 alcohol hydroxyl groups,(b) a solvent which is inert with respect to isocyanate groups in which the (a1) organic polyisocyanate is a polyisocyanate with exclusively aliphatically or cycloaliphatically bound isocyanate groups and the a2) polyhydroxyl compound is a polysiloxane of the molecular weight range of 300 to 5000 which has at least 2 alcoholically bound hydroxyl groups.A method of impregnating mineral substrates with such impregnating agents is also provided.
摘要:
In a construction material comprising a flexible carrier substrate impregnated or coated with a water-hardening resin, the resin contains as an additive polyether polysiloxane polyurethanes of the formula ##STR1## in which R.sup.1 is lower alkyl,m is the average number of siloxane groups in the range from 5 to 25,R is ##STR2## in which X is lower alkylene,Y is an aliphatic, cycloaliphatic, aromatic or araliphatic moiety, which is unsubstituted or substituted by further ##STR3## Z is a polyether moiety based on ethylene oxide units propylene oxide units, or both with the average number of ethylene oxide and propylene oxide units being in the range fro 10 to 100 andR.sup.2 is lower alkyl.
摘要:
Liquid crystalline bis-chlorocarbonic acid esters are 4-hydroxybenzoic acid-(4'-hydroxyphenyl) esters corresponding to the following formula ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 denote, independently of one another, hydrogen, a halogen atom or a C.sub.1 to C.sub.6 alkyl group. Preparation of (I) and liquid crystalline N-alkyl polyurethanes and polycarbonates prepared from (I) are other invention embodiments.
摘要:
The present invention relates to the use of organic compounds which contain epoxide groups and which are subjected to a heat treatment at 30.degree. to 150.degree. C. in the presence of an alkylating agent, as auxiliary substances to increase the weather resistance of molded plastic parts. These molded parts are produced by the reaction injection molding technique and the process comprises reacting reaction mixtures based on polyioscyanate addition products.
摘要:
A moisture cured adhesive comprising a reaction product of an organic polyisocyanate and an organic polyhydroxyl component which comprises at least one polyether polyol which has been modified by radical polymerization or copolymerization with an olefinically unsaturated monomer is disclosed. The reaction product is characterized in that it contains about 2.5 to about 25% by weight of free isocyanate groups and in that the proportion of polymers or copolymers present in the organic polyhydroxyl component is about 1 to about 50 weight % based on the weight of the components. The adhesive in accordance with the invention is characterized by its superior shear strength.
摘要:
Liquid crystalline bis-chlorocarbonic acid esters are 4-hydroxybenzoic acid-(4'-hydroxyphenyl) esters corresponding to the following formula ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 denote, independently of one another, hydrogen, a halogen atom or a C.sub.1 to C.sub.6 alkyl group. Preparation of (I) and liquid crystalline N-alkyl polyurethanes and polycarbonates prepared form (I) are other invention embodiments.
摘要:
The present invention is directed to polyisocyanate compositions containing(a) at least one organic polyisocyanate and(b) at least one dissolved catalyst corresponding to the general formula ##STR1## wherein R.sup.1 and R.sup.2 may be identical or different and denote hydrogen or a methyl group, provided that R.sup.1 and R.sup.2 do not both stand for a methyl group,R.sup.3, R.sup.4 and R.sup.5 denote identical or different organic groups which are inert in isocyanate addition reactions andk, m and n represent identical or different integers with values from 1 to 5.The present invention also relates to the use of the polyisocyanate compositions as the polyisocyanate component for the production of polyisocyanate polyaddition products, especially moisture cure coating compositions or adhesives.
摘要:
Foaming during setting of a polyurethane fixed dressing, e.g. cast for broken arm, is minimized by utilizing as the dressing a polyisocyanate composition comprising:a) at least one organic polyisocyanate,b) at least one catalyst andc) at least one compound of the formula ##STR1## in which R represents methyl, ethyl or propyl and 1.ltoreq.n.ltoreq.4.
摘要:
A method for protecting the integrity of a set of memory pages to be accessed by an operating system of a data processing system, includes running the operating system in a virtual machine (VM) of the data processing system; verifying the integrity of the set of memory pages on loading of pages in the set to a memory of the data processing system for access by the operating system; in response to verification of the integrity, designating the set of memory pages as trusted pages and, in a page table to be used by the operating system during the access, marking non-trusted pages as paged; and in response to a subsequent page fault interrupt for a non-trusted page, remapping the set of pages to a region of the data processing system memory which is inaccessible to the virtual machine.