Structure-Property Relationships


Method of curing polyurethane prepolymers with liquid extender comprising 4,4{40 -methylenebis (2-chloroaniline) and low molecular weight polytetramethylene ether glycol
US 3718624 A

This invention relates to the curing of isocyanate terminated polyurethane prepolymers with a liquid extender consisting of 4,4'-methylenebis(2-chloroaniline) and low molecular weight polytetramethylene ether glycol. Learn more.

Polyurethane Elastomers Based on Poly (E-Caprolactone)Polyols
US 3775354

Solid and microcellular polyurethane elastomers prepared by reacting (a) liquid polyesters containg from about 25 percent by weight to about 70 percent by weight of the epsilon-oxycaproyl unit, the balance of the pollster being derived from the reaction of at least on dicarboxylic acid with at least two glycols selected from the group consisting of ethylene glycol, 1,3-propanediol, 1,4-butanediol and 1,5-pentanedial, (b) an organic poly-isocyanate, and optionally (c) a chain extender comprising water, glycols, amino alcohols, or diamines. If the liquid polyester (a) is branched, for example, by addition of small quantities of a triol, the reaction with the organic polyisocyanate may be conducted in the absence of a chain- extender. Processes for producing these elastomers are also disclosed. Learn more.

Mixtures of high and low molecular weight polyols resistant to phase separation 
US 3993576

Mixtures of high molecular weight polyols and low molecular weight polyols such as mixtures of glycerine initiated polyoxypropylene glycols and mono- and diethylene glycols are solubilized and therefore rendered resistant to phase separation upon storage by the addition thereto of an effective quantity of a derivative of butylene glycol or propylene glycol such as dibutylene glycol. Learn more.

Novel polyurethane curative
US 4089822 

A polyurethane elastomer exhibiting a low glass transition temperature is provided, which comprises the reaction product of (a) a polyurethane prepolymer having terminally reactive isocyanate groups, prepared by reaction of a polymeric diol with a stoichiometric excess of 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate or a mixture of tolylene diisocyanates containing a major proportion of the 2,4-isomer, with (b) from 80 to 110% of the stoichiometrically required amount of 2,6-dichloro-p-phenylene diamine, and (c) from about 0.01 to 1 part per hundred of prepolymer of a conventional polyurethane catalyst. Learn more.

Polyurethane elastomer composition 
US 4555562

A polyurethane elastomer product formed by curing a mixture of an NCO terminated urethane prepolymer and a polyhydroxyalkylphosphine oxide. The polyhydroxyalkyl phosphine curative is a compound of the class having the formula: ##STR1## wherein R is alkylene of 3 to 6 carbon atoms, R.sub.1 is alkyl of 2 to 10 carbon atoms, cycloalkyl of 6 to 12 carbon atoms and n is an integer of 2 to 3. Exemplary polyhydroxyalkyl phosphine curatives are (HOCH.sub.2 CH.sub.2 CH.sub.2).sub.2 P(O)--C.sub.4 H.sub.9 --sec. and (HOCH.sub.2 CH.sub.2 CH.sub.2).sub.3 P(O). Learn more.

Ether-based polyurethane elevator sheave liner-polyurethane-urea made from polyether urethane prepolymer chain extended with polyester/diamine blend
US 5112933 A

An ether-based polyurethane article comprises a toluene diisocyanate-terminated polyether polyol prepolymer cured with a blended polyester polyol/diamine curative. The article may be made by mixing a toluene diisocyanate-terminated polyether polyol prepolymer with a blended polyester polyol/diamine curative to form a reaction mixture. A suitably shaped mold is preheated and filled with the reaction mixture with sufficient pressure to displace air in the mold. The reaction mixture is held in the preheated mold to cure the reaction mixture and form the article. The cast article is removed from the mold and post-cured to complete the chemical cross-linking reaction. Learn more

One-shot polyurethane elastomers with very low compression set
US 6277943 B1 

The present invention relates to a process for the production of one-shot polyurethane elastomers having low compression sets. This process comprises reacting a polymethylene poly(phenylisocyanate) having an average functionality of 2.2 to 2.8, and a polyol component that has an average functionality of 2.0 or less. The polyol component comprises at least one relatively high molecular weight isocyanate-reactive component, and at least one relatively low molecular weight isocyanate-reactive component, with the functionalities and quantities of each component being such that the above average functionality of 2.0 or less for the polyol component is satisfied. Polyurethane elastomers produced by the process of this invention are characterized by compression sets of less than 10%. Learn more.