摘要:
A prepolymer mixture for preparing a polyurethane elastomer, the mixture comprising an isocyanate terminated prepolymer and a nitrogen-containing organic salt. The nitrogen-containing organic salt may be selected from the group consisting of an ammonium salt, an imidazolium salt, a pyridinium salt, a pyrrolidinium salt, a piperidinium salt, and a morpholinium salt.
摘要:
A prepolymer mixture for preparing a polyurethane elastomer, the mixture comprising an isocyanate terminated prepolymer and a nitrogen-containing organic salt. The nitrogen-containing organic salt may be selected from the group consisting of an ammonium salt, an imidazolium salt, a pyridinium salt, a pyrrolidinium salt, a piperidinium salt, and a morpholinium salt.
摘要:
A process of preparing para phenylenediamines, such as, p-aminodiphenylamine. The process involves contacting nitrobenzene or a substituted derivative thereof with hydrogen and an amine, such as aniline, in the presence of a hydrogenation catalyst, a hydrogenation inhibitor, and an acid cocatalyst under reaction conditions.
摘要:
An externally heated reaction injection molding (“RIM”) system and processes for producing polyurethane articles. The system comprises a mixing chamber for combining a prepolymer and a chain extender and one or more heating systems for heating at least one of the prepolymer and the chain extender upstream of the mixing chamber. In one embodiment, the process comprises injecting a heated prepolymer and/or a heated chain extender into a mixing chamber and initiating a curing of the prepolymer in a mixing chamber. By employing heat to decrease the viscosity of the prepolymer and/or the chain extender, prepolymers and/or chain extenders that have high room temperature viscosities or are in the solid state at room temperature, may be utilized in the RIM system.
摘要:
Tire tread compositions comprisinga) a first rubber component comprising about 60-90 parts of styrene butadiene rubber (SBR) comprising less than 20 percent by weight of styrene, per hundred parts of rubber (phr);b) a second rubber component comprising about 10-40 phr of nitrile-butadiene rubber (NBR);c) 30-80 phr of carbon black;d) 10-20 phr of silica;e) 1-3 phr of a silane coupling agent; and, optionally,f) a third rubber component comprising about 10-30 phr of a high cis polybutadiene rubber (cis BR). The tire tread compositions provide tires with excellent wet traction and low rolling resistance.
摘要:
Processes of preparing para substituted phenylamines, such as, p-phenylenediamines, and particularly, p-aminodiphenylamine. One process involves contacting phenylhydroxylamine with a nucleophilic reagent, such as aniline, in specified proportions and within a specified temperature range, in the absence of oxygen, and in the presence of a homogeneous acid catalyst, such as hydrochloric acid. A second process involves contacting phenylhydroxylamine with a nucleophilic reagent, such as aniline, in the presence of a solid acid catalyst, such as acidic zeolite Y, under reaction conditions.