Abstract:
PROBLEM TO BE SOLVED: To obtain the subject emulsion capable of generating a hard polyurethane foam having closed cells or open cells not containing a halogen, by making the emulsion include a reactive hydrogen atom-containing compound, a foaming agent, an auxiliary agent and an additive and using a specific emulsifying auxiliary agent. SOLUTION: This emulsion includes (A) a compound containing a hydrogen atom reactive with isocyanate, (B) a foaming agent and (C) an auxiliary agent and an additive. The emulsion includes a polyester alcohol of the formula (m) is 0-15; (n) is 0-1; (o) is 0-15; (p) is 0-1; (q) is 0-15; (r) is 0-1; (s) is 0-15; (t) is 0-1; (u) is 0-10; (v) is 0-15; (x) is 1-5; (y) is 1-4 or a mixture of 1 to 3 when (r+n)≠0; (z) is 0-3; (zi is 0.1-3; R1 is a fatty structural substance based on a multifunctional alcoholic structure not having OH group; R2 is a group of polycarboxylic acid not having COOH; R3 is an alcoholic group same as R1 } and the component B exists in an emulsified state in the component A and the component C.
Abstract:
PROBLEM TO BE SOLVED: To obtain the subject foamed material having low thermal conductivity and improved thermal strain resistance and useful for a plastic-coated pipe, etc., without using a halogenated hydrocarbon foaming agent by reacting a polyisocyanate with a specific compound under specific condition. SOLUTION: A rigid polyurethane foam is produced by reacting (A) a polyisocyanate with (B) a compound having hydrogen atom reactive with isocyanate and composed of a mixture of (i) a polyol produced by the addition reaction of ethylene oxide, etc., to hexitol (mixture) and (ii) a polyol produced by the addition reaction of ethylene oxide, etc., to an aromatic amine wherein the hexitol content in the mixture is 15-30wt.%, the amine content is 1-10wt.% and the ratio of the polyol mixture is 60-1.00 pts.wt. based on 1.00 pts.wt. of the constituent components in the presence of (C) water and optionally further (D) a physical foaming agent and (E) a catalyst, etc.
Abstract:
PROBLEM TO BE SOLVED: To provide a rigid foam based on an isocyanate compound, using a foaming agent not causing an environment disruption, capable of being produced by a conventional technology for producing rigid foams, and provided with resistance to high temperature, low heat conductivity at high temperature and low brittleness. SOLUTION: This thermally stable rigid foam comprises (a) a polyisocyanate, (b) a polyol, (c) water in an amount of at most 2 wt.%, and (d) 5-30 wt.% of a hydrocarbon and/or a fluorinated hydrocarbon as a foaming agent. The polyol (b) comprises (bi) at least one polyetheralcohol having a functional value number of at least 1.5 and hydroxyl groups of 10-100 mgKOH/g in an amount of 0.2-80 wt.% based on the component (b) and (bii) at least one polyesterpolyalcohol in an amount of 5-90 wt.% based on the component (b).
Abstract:
PROBLEM TO BE SOLVED: To provide an emulsion containing a halogen-free foaming agent for producing rigid foam based on isocyanate groups that brings about the properties improved by processing (in other words, improved heat stability and/or good foaming of the reaction mixture). SOLUTION: This emulsion contains (a) a compound bearing hydrogen atoms reactive to isocyanate, (b) water, (c) a halogen-free foaming agent having physical activity, and, when necessary (d) auxiliary agents and/or usually used additives. In this case, the components (a) contains 0.2-80 wt.% of polyether alcohol with the functionality of > 1.5 and the hydroxyl value of 10-100 mg KOH/g and the physically active halogen-free foaming agent (c) is hydrocarbon of 3-10 carbon atoms.
Abstract:
The invention relates to prepolymers which contain isocyanate groups and which can be produced by reacting an isocyanate mixture, said mixture being predominantly comprised of diphenylmethane diisocyanates and polyphenyl polymethylene polyisocyanates, with a maximum proportion of two-core isomers of 74 wt.% with at least 4 functional polyols or with a mixture of polyols having an average functionality of at least 4. The polyols or polyol mixture comprise(s) a hydroxyl value ranging from 200 to 1650 mg KOH/g and an average molar mass of less than 1100 g/mol with an NCO content of at least 30.0 wt.%. In addition, the invention relates to a method for producing these prepolymers which contain isocyanate groups, to their use for producing polyurethanes, and to a method for producing polyurethanes by reacting at least one of the inventive prepolymers which contain isocyanate groups, optionally mixed with additional organic and/or modified organic isocyanates (a), with compounds having at least two reactive hydrogen atoms (b) in the presence of optional expanding agents (c), catalysts (d), optional additional auxiliary agents and/or additives (e).
Abstract:
The invention concerns a foam consisting of at least 70 wt. % of carbon, having an average cell size more than 30 mu m, porosity between 35 % and 99.7 %, a percentage of open cells higher than 90 %, and comprising linking elements between the cells, which, viewed in cross-section, form a triangle with inward-curving sides. Inside the surface of the cross-section, the sum of the surfaces having a cavity constitutes less than 5 % of the total cross-sectional area of the linking elements. The invention also concerns the use of said foams consisting for the major part of carbon in electrical and electrochemical applications, in the form of filtering material, heat insulation material, support material, storage material and as starting material for other transformations. The invention further concerns a method for producing a foam consisting of at least 70 wt. % of carbon, by pyrolizing synthetic foams. Said method is characterized in that the synthetic foams used contain at least 30 wt. % of a polymer material having a nitrogen content higher than 6 wt. %, and having a porosity between 20 and 99 %, as well as a percentage of open cells higher than 1 %.
Abstract:
The invention relates to carbon materials consisting of at least 70 wt. % carbon with a partial graphite structure. Said materials are characterised by 2 signals in the Raman spectrum excited at 488 nm for numbers of waves of 1595 cm and 1370 cm , the half-width of the signal for numbers of waves of 1595 cm (signal number 1) being less than 180 cm and the half-width of the signal for numbers of waves of 1370 cm (signal number 2) being less than 280 cm . The ratio of the products of the half-width and the intensity of the signals for signal number 1 to signal number 2 is greater than 0.5. The invention also relates to a method for producing said materials and to their use in electrical and electrochemical applications, in particular for electric energy accumulation.
Abstract translation:本发明的目的是至少70种现有重量%的碳的碳材料具有部分石墨结构,其特征在于在488nm的拉曼光谱激发在波数约1595 2个信号厘米<-1>和1370厘米< - 1>,其中,在波数的信号的半宽度1595厘米<-1>(信号数目1)小于180 CM <-1>和在波数的信号的半宽度1370厘米<-1>(信号数2)较小 并且信号编号1的信号的半高宽与信号编号2的乘积之比大于0.5,以及它们的制备方法及其在电气和电化学应用中的用途, 特别是对于电能储存。
Abstract:
Emulsions containing polyether alcohols and polyester alcohols are used in the production of hard foams based on isocyanates to improve the temperature stability of the foams. Temperature-stable hard foams based on isocyanates are produced by reacting (a) polyisocyanates with (b) compounds with at least two hydrogen atoms reactive with isocyanate groups and (c) water in the presence of (d) propellants and optionally catalysts and auxiliary aids and additives. (b) comprises (bi) a polyether alcohol present in an amount of 0.2-80 wt.% and having a functionality of at least 1.5 and an OH number of 10-100 mg KOH/g, and (bii) a polyester alcohol present in an amount of 5-90 wt.%. (c) is present in an amount of maximum 2 wt.%. (d) contains hydrocarbons and/or hydrocarbons containing fluorine in an amount of 5-30 wt.%.
Abstract:
PCT No. PCT/EP96/05640 Sec. 371 Date Oct. 7, 1998 Sec. 102(e) Date Oct. 7, 1998 PCT Filed Dec. 16, 1996 PCT Pub. No. WO97/23535 PCT Pub. Date Jul. 3, 1997A microcellular PU elastomer having improved dynamic mechanical properties and based on an isocyanate component consisting essentially of 4,4'-MDI and further customary constituents has a physicochemical structure which, in the gel permeation chromatograph (GPC) of a solution of the microcellular polyurethane elastomer prepared at 90 DEG C. in N,N-dimethylformamide containing 1 percent of di-n-butylamine measured against polymethyl methacrylate (PMMA) as standard, displays a signal occurring in addition to low molecular weight main signal and comprising one or more peaks at an (apparent) molar mass of greater than 250,000 g/mol which becomes smaller or disappears on addition of lithium chloride to this solution, and a urea content of from 14 to 18% by weight. A process is also provided for preparing such a microcellular PU elastomer having improved dynamic mechanical properties. The microcellular PU elastomers can be used for producing damping elements.