摘要:
A process for preparing dihydroxytoluene by heating toluene diisocyanate distillation residue in the presence of an aqueous solution of phosphoric acid.
摘要:
A water-dispersible polyurethane resin is disclosed. The resin comprises recurring units of an alkoxylated phenolic resin, a carboxylate-containing diol, and a multifunctional isocyanate. The resin, which can be neutralized, and/or chain-extended, is dispersed in water to form a polyurethane dispersion. Coatings derived from the polyurethane dispersions have excellent acid and chemical resistance.
摘要:
Disclosed are new coatings compositions based on an HDI isocyanurate or biuret polyisocyanate and a bis(imine) reaction product of a diaminoalkane containing between two and five carbon atoms with an alkyl aldehyde containing between four and seven carbon atoms (advantageously a bis(imine) product of the reaction of 1,4-diaminobutane and isobutyraldehyde). The latter bis(imine) is completely miscible in HDI isocyanurate and biuret polyisocyanates, and, as a reactive diluent, allows the preparation of high performance coatings formulations that require only small amounts of solvents to achieve a conveniently sprayable viscosity.
摘要:
Disclosed herein is a liquid, monoallophanate-containing, monouretidione-containing polyisocyanate composition characterized by having (i) an isocyanate functionality of between 2.8 and 6.5, (ii) a free NCO content of 10% to 47% by weight, (iii) a viscosity of less than 1000 cp (25.degree. C.), and (iv) the presence of monouretidione and monoallophanate groups in a molar ratio of said monouretidione groups to said monoallophanate groups of between about 20:1 and about 1:5. Also disclosed is a process for producing the above compositions, as well as their use, optionally in blocked form in one or two component coating compositions.
摘要:
A multi-step process for producing DNT employing a mononitration step in a single liquid phase at an elevated temperature using a carefully controlled amount of water, followed by a phase separation step prior to dinitration of the MNT present in the resulting organic phase. This process results in a DNT product with a desired isomer ratio of 2,4-DNT to 2,6-DNT and provide relatively fast nitration rates with less by-products.
摘要:
Described is a process for making rigid polyurethane foam from a reaction formulation including a novel surfactant composition comprising select trialkoxysilanols or alkoxysilane cluster compounds.