摘要:
A process for the production of solid polyisocyanates stabilized by a polymer coating and showing retarded reactivity comprising reacting(1) one or more solid polyisocyanates in particulate form, said polyisocyanates having melting points above 30.degree. C., and(2) from 0.1 to 25 equivalent percent of amine per isocyanate equivalent of an organic compound having a molecular weight of from 32 to 6000, said organic compound being selected from the group consisting of(a) di- or higher functional compounds containing 2 or more aliphatically-bound primary and/or secondary amino groups,(b) compounds containing one or more terminal --CO--, --NH--, --NH.sub.2 -- groups,(c) hydrazines, and(d) mixtures thereofsaid reaction being conducted at a temperature below the melting temperature of said solid polyisocyanate, and being conducted in the presence of(3) a liquid medium selected from the group consisting of(a) organic compounds containing one or more hydroxy groups and having molecular weights of from 62 to 6000,(b) organic compounds containing 2 or more aromatically-bound amino groups and having molecular weights of from 108 to 6000,(c) organic compounds containing 2 or more aliphatically-bound amino groups and having molecular weights of from 400 to 6000,(d) plasticizers,(e) water, and(f) mixtures thereofto form a suspension of polyadduct-coated, stabilized polyisocyanate in the liquid medium.
摘要翻译:一种制备通过聚合物涂层稳定并显示延迟反应的固体多异氰酸酯的方法,包括使(1)一种或多种颗粒形式的固体多异氰酸酯,所述多异氰酸酯的熔点高于30℃,和(2)0.1至25 所述有机化合物选自(a)含有2个或更多个脂族结合的伯和/或低级官能化合物的二官能或更高级的官能化合物, 或仲氨基,(b)含有一个或多个末端-CO-,-NH-,-NH 2 - 基团的化合物,(c)肼和(d)其混合物,所述反应在低于 所述固体多异氰酸酯,并且在(3)选自以下的液体介质存在下进行:(a)含有一个或多个羟基并具有分子量的有机化合物 m 62至6000,(b)含有2个或更多芳族结合氨基并且分子量为108至6000的有机化合物,(c)含有2个或更多个脂族结合的氨基并且分子量为400的有机化合物 至(6000),(d)增塑剂,(e)水和(f)它们的混合物,以形成在液体介质中形成多加合物涂覆的稳定化多异氰酸酯的悬浮液。
摘要:
A medical aid for supporting the function of the knee joint, in particular a knee joint orthosis with a pad engaging around the patella of the knee joint. An improved patellar pad has the additional function of supporting movement and has additional preventive/therapeutic functions.
摘要:
The invention relates to a bandage for knee joints comprising an elastic textile stocking, an annular or clasp-like elastic profiled insert arranged in or at the textile stocking to encase at least the lateral (fibula-side) section of the patella of the knee joint and at least one flexible, inelastic tensile strap essentially extending in the longitudinal direction of the bandage over the knee joint.
摘要:
The present invention is directed to a polyurethane reactive adhesive compound comprising:A) one or more polyisocyanates having an inactivated particle surface,B) at least one isocyanate reactive compound having a molecular weight MG.sub.w greater than 400, andC) finely dispersed polymer particles, wherein the polymer is solid at temperatures below 70.degree. C. and has a molecular weight MG.sub.w of at least 3000.
摘要:
High molecular weight amines having reduced low molecular weight amine contents are obtained by reacting a mixture of (1) a high molecular weight amine and (2) a low molecular weight amine with (3) an isocyanate in quantities such that from 0.5 to 10 equivalents of isocyanate are present for each equivalent of low molecular weight amine. The product of high molecular weight amines is particularly useful in the production of isocyanate addition products such as polyurethane plastics and foams.
摘要:
A composite plastic molding made up of a plastic foam and having a polyurethane skin is made by heating a reactive one-component system to form a polyurethane skin and then joining the polyurethane skin to the plastic foam. The one-component system is composed of a finely divided polyisocyanate in which from 0.1 to 25 equivalent percent of the isocyanate groups have been deactivated, a polyamine and/or polyol having a molecular weight of from 400 to 8000 and optionally a chain extending agent, a catalyst and known auxiliaries and additives.
摘要:
The present invention is directed to a process for the preparation of finely divided solid polyisocyanates containing urea groups by reacting organic polyisocyanates which are free from urea groups with water in an aqueous emulsion, characterized in that the reaction is carried out in the presence of an emulsion- and dispersion-stabilizing compound.
摘要:
The present invention relates to a process for the dimerization of 4,4'-diisocyanatodiphenylmethane from emulsion in apolar solvents with the formation of complexes and to the complexes obtainable for the first time by this process. The complexes consist of one mol of low molecular weight 4,4'-diisocyanato-diphenylmethane-uretdione or its low oligomers corresponding to the idealized formula (I) ##STR1## (n=0 to 0.5, where n is the average degree of oligomerization of the dimer) and 2 to 3 mol of 4,4'-diisocyanatodiphenylmethane (MDI) ##STR2## In the process according to the invention, 4,4'-diisocyanatodiphenylmethane (II) in the molten form is emulsified in apolar solvents. Dimerization is started in the presence of conventional dimerization catalysts at temperatures above the melting point of MDI, preferably up to an upper temperature limit of 50.degree. to 60.degree. C. The temperature is then lowered to
摘要:
This invention relates to the production of polymer-coated, finely divided polyisocyanates by mixing(A) solid, finely divided polyisocyanates (preferably dimeric diisocyanates or urea diisocyanates) with(B) polyisocyanates differing in composition from those mentioned under (A) (preferably (cyclo) aliphatic polyisocyanates, such as biuretized diisocyanates or trimers or NCO-prepolymers),in quantities of from 0.05 to 50 parts by weight, and preferably in quantities of from 0.2 to 25 parts by weight, of (B) per 100 parts by weight of (A). The solid polyisocyanate particles surface-modified by covering with polyisocyanates (B) and then reacted with(D) isocyanate-reactive compounds containing reactive hydrogen atoms or with compounds free from active hydrogen atoms which form polymers with isocyanates in sub-equivalent to substantially equivalent quantities (preferably 0.5 to 1.0 equivalent per NCO-equivalent), in the presence of(C) inert, weakly polar organic solvents, (for example aliphatic hydrocarbons or relatively long chain dialkyl ethers), plasticizers, polyols or aromatic polyamines.A polymer coating is formed by the reaction of (B) and (D) around the solid polyisocyanate cores (A).The present invention also relates to the polyisocyanate particles covered with polyisocyanates (B) on the surface of the solid polyisocyanates (A) and, in particular, to the foreign-polymer coated, finely particulate polyisocyanates of retarded reactivity obtained by reaction with (D).The present invention also relates to the use of the polyisocyanate-covered and, more particularly, polymer-coated polyisocyanates, optionally in suspension in polyols and/or plasticizers, for the production of polyurethanes, more particularly in one-component polyurethane reactive systems having a long shelf life and a high thickening point.
摘要:
According to the present invention, relatively high molecular weight aliphatic and/or aromatic polyamines having molecular weights of from 400 to 8,000 (preferably from 600 to 4,000) are mixed with substantially equivalent quantities of low molecular weight, solid, finely-divided diisocyanates having a melting point of >40.degree. C., (preferably >80.degree. C.), such as phenylene diisocyanate, naphth lene-1,5-diisocyanate, dimeric toluylene-2,4-diisocyanate or the urea diisocyanate of toluylene-2,4-diisocyanate. This mixture, having a pot life of at least several minutes, is subsequently heated to a relatively high temperature, such as from 80.degree. to 200.degree. C.The products obtained have excellent elastic properties over a broad temperature range. They have an exceptionally flat modulus of elasticity curve (G') in the torsional vibration test. The hard and soft segments are markedly segregated and are thus not substantially disturbed by reciprocal interaction causing "softening".