摘要:
A curable polyisocyanate composition comprising at least one or more polyisocyanate compounds, at least one or more trimerization catalyst compounds, at least one or more aldehyde compounds wherein the aldehyde compound is selected from compounds with the structure R—CHO wherein CHO is an aldehyde group and R is a hydrocarbyl group selected from an alkyl, alkenyl or aryl having 1-50 carbon atoms, preferably 1-20 carbon atoms, and at least one or more compounds selected from compounds which comprise a carboxamide group having the structure —CO—NH2 and/or from compounds which comprise a group having the structure —CO—NH—CO—.
摘要:
The invention relates to a method for preparing an aromatic polyisocyanate in an isocyanate plant comprising a reaction section for a phosgenation reaction, wherein a primary aromatic amine is reacted with phosgene compounds in a reaction section to obtain an isocyanate comprising reaction product and wherein CO2 concentration in the gases coming from the reaction section is measured and analyzed, and wherein the conditions in the phosgenation reaction are adjusted in case the CO2 concentration in the gases coming from the reaction section is higher than a background CO2 concentration.
摘要:
A reinforced organic natural fiber composite material having a lambda value in the range 15-35 mW/m·K is disclosed which comprises 25-85% by weight hydrophobic nanoporous particles calculated on the total weight of the composite material, at least 10% by weight organic natural fibers having isocyanate reactive groups calculated on the total weight of the composite material and 1-15% by weight binder selected from a polyurea/polyurethane comprising binder made from emulsifiable polyisocyanate, water and surfactants.
摘要:
Process for preparing rigid polyurethane or urethane-modified polyisocyanurate foams from polyisocyanates and polyfunctional isocyanate-reactive compounds in the presence of blowing agents wherein the polyfunctional isocyanate-reactive compounds comprise a polyether polyol having a hydroxyl number of between 50 and 650 mg KOH/g obtained by reacting a polyfunctional initiator first with ethylene oxide and subsequently with propylene oxide wherein the propoxylation degree is between 0.33 and 2 mole propylene oxide per active hydrogen atom in the initiator and wherein the molar ratio of ethylene oxide to propylene oxide in said polyether polyol is at least 2.
摘要:
The invention relates to a process for preparing a polysaccharide derivative, comprising the steps of: (a) contacting at least one polysaccharide with at least one polysaccharide swelling agent at a temperature of at most 70° C.; and (b) subsequently, contacting the product of step (a) with at least one aromatic isocyanate; thereby preparing a polysaccharide derivative.
摘要:
The present invention relates to a tin-free composition comprising at least one silylated polymer and at least one tin-free polyhedral oligomeric metallo silsesquioxane. The present invention also relates to a process of curing a composition comprising a silylated polymer comprising the step of: contacting a silylated polymer with a tin-free polyhedral oligomeric metallo silsesquioxane.
摘要:
Amine compositions comprising sterically hindered amines and associated methods are provided. In some embodiments, amine compositions of the present disclosure may be useful for selective removal of H2S from an acidic gas stream.
摘要:
New stabilizers for solutions of choline hydroxide and related quaternary trialkylalkanolamines are disclosed. The stabilizers are alkyl hydroxylamines, hydrazines, hydrazides, or derivates thereof, including compounds containing more than one such functionality. The new stabilizers are effective at concentrations less than about 1000 ppm, and choline hydroxide solutions stabilized with the compounds described herein typically have Gardner Color change less than about 2.0 after six months at reasonable temperatures.
摘要:
A method of producing a carbonate product including mixing a DMC and methanol mixture with an alcohol, reacting the DMC with the alcohol to form carbonate product, and removing a substantial portion of unreacted DMC and methanol. In one embodiment, the method may be repeated to reach a desired alcohol conversion by adding more DMC and methanol mixture.