Catalysis
Metallo-organic catalyzed one-shot process for preparing urethane-urea elastomers
US 3203932
ABSTRACT
This invention relates to a direct, one-step method for preparing urethane-ura cast elastomers.
It is disclosed in the prior art that urethane-urea cast elastomers can be prepared by a two-step process. In the first step, an isocyanate terminated prepolymer is prepared by interacting, for example, polytetramethylene glycol and tolylene diisocyanate. Learn more
Delayed Polyurethane Action Catalyst
US 3862150
ABSTRACT
Novel salts of tertiary amines and alpha-substituted carboxylic acids have advantages as delayed action thermally activated catalysts such as in urethane and epoxy catalysis. Some salts of tertiary amines tend to dissociate reversibly when heated. However, the compounds of the present invention preferentially decompose, irreversibly, to generate carbon dioxide when heated. Learn more
Polyurethane elastomers having prolonged flex life and tires made therefrom
US 3980606 A
ABSTRACT
Polyurethane elastomers having prolonged flex life are prepared by reacting a diisocyanate with polypropylene glycol (PPG) or triol and poly(tetramethylene ether) glycol (PTEG). The diisocyanate may be reacted with each glycol separately or they may be mixed before the reaction. A smaller amount of the prepolymer obtained from the polypropylene glycol or triol is mixed with a larger amount of the prepolymer obtained from the poly(tetramethylene ether) glycol and the mixture is reacted with a hindered aromatic diamine. Elastomers cured from the resulting mixed polyurethane were found to have an exceptionally high flex life and are particularly useful in the production of products which undergo dynamic flexing, as in the preparation of pneumatic tires, particularly the sidewalls thereof, because of their exceptionally long flex life. Learn more
Catalyzed one-shot system for molding thermoset polyurethanes
US 4119594 A
ABSTRACT According to a preferred practice of the invention, thermoset polyurethanes are molded from a mixture of solid particles of hydroquinone di-(beta-hydroxyethyl)ether (HQEE) and zinc stearate dispersed in a liquid mixture of a polyether polyol and a liquid form of diphenylmethane diisocyanate. The use of the HQEE chain extender and the zinc stearate catalyst provides a unique one-shot molding mixture that is relatively unreactive at room temperature, but polymerizes and cures rapidly upon heating. It has a pot life of at least several hours and is suitable for use in injection molding equipment generally used in processing thermoplastic material. Learn more
Deactivation of polyester catalyst residues
US 4401804
ABSTRACT A process is provided for deactivation of catalyst residues in polyester compositions. The polyester compositions are provided by polymerizing diols and diacids, or mixtures of such diols and diacids, to form polyester compositions. The polymerization is carried out in the presence of a polymerization catalyst that leaves traces of such catalyst residues in the polyester composition. These catalyst residues can adversely affect the further processing and end use of the polyester composition. The present process provides deactivation of the catalyst residues by the use of a combination of a mono- or dihydrogen phosphonate or mono-, di-, or trihydrogen phosphate compound and a di- or triester phosphonate compound or a phosphite compound. Learn more
Bismuth catalyst system for preparing polyurethane elastomers
US 4584362 A
ABSTRACT
Processes are provided for preparing polyurethane elastomers by reacting a polyether or polyester polyol with a polyisocyanate in the presence of a catalytic amount of a bismuth salt of a carboxylic acid having from 2 to 20 carbon atoms. The catalysts of these processes are relatively non-toxic, yet they promote rapid polymerization for a wide variety of polyurethane elastomeric applications. Learn more
Sulfonic acid blocked metal catalysts for amine trigger urethane reactions
US 5849864
ABSTRACT
The present invention is addressed a formulation curable in the presence of an amine and containing one or more of a polyol or polymercapto resin, a polyisocyanate cross-linking agent, optionally a organic vehicle, and a tin catalyst complex. The present invention comprises the catalyst complex being formed from a metal catalyst and a complexing sulfonic acid in an equivalent ratio of complexing sulfonic acid to metal catalyst of greater than 2:1. Such curable formulation may be compounded into a coating, an adhesive (including a structural adhesive), a caulk, a foundry binder, or the like. Besides having excellent shelf life, long periods of open time are experienced with the novel catalyzed formulation. However, upon exposure to an amine, the catalyst complex becomes activated and then is effective to catalyze the NCO--OH reaction or the NCO--SH reaction to effect cure of the formulation. Learn more
Heat activated tertiary amine urethane catalysts
US 7351859
ABSTRACT
This invention concerns a compound formed from a tertiary amine-carboxylic acid salt, where the carboxylic acid and tertiary amine are selected such that the catalyst salt is blocked at room temperature and becomes unblocked at an elevated temperature. The compound is useful as a heat activated urethane catalyst. Learn more
|
