Spandex elastomers
AssigneeArco Chemical Technology, L.P.
InventorsStephen D. Seneker, Bruce D. Lawrey
Life of this patent
Estimating the term…
Abstract
Substitution of from 5 to 50 equivalent percent of an ultra-low unsaturation polyoxypropylene diol for PTMEG in isocyanate-terminated prepolymers used in spandex production is found to lower considerably both prepolymer viscosity and hysteresis while substantially retaining other desirable physical properties. Such products may offer higher fiber production rates than are possible while employing an all PTMEG-derived polymer.
Claims19
A segmented polyurethane/urea spandex elastomer prepared by reacting in solution:
- a) an isocyanate-terminated prepolymer prepared by reacting a stoichiometric excess of one or more di- or polyisocyanates, so as to provide a free NCO group content of said prepolymer of from about 0.5% by weight to about 10% by weight based on prepolymer weight, with a polyol component comprising in most major part a diol component, said diol component comprising from about 5 equivalent percent to about 50 equivalent percent of one or more ultra-low unsaturation polyoxypropylene diols having a molecular weight in excess of about 1500 Da and an average unsaturation of less than about 0.010 meq/g, and from about 95 equivalent percent to about 50 equivalent percent of one or more polytetramethylene ether glycols having a molecular weight of from about 600 Da to about 6000 Da;
- with
- b) a diamine chain extender comprising one or more aliphatic diamines, cycloaliphatic diamines, or their admixture.
A process for the reduction of PTMEG contained in the soft segments of segmented, polyurethane/urea spandex polymers while maintaining unload power or percent set, comprising substituting for from 5 equivalent percent to 50 equivalent percent of PTMEG one or more ultra-low unsaturation polyoxypropylene polyols having molecular weights from about 1500 Da to 20,000 Da and an average unsaturation less than 0.010 meq/g.
A process for the reduction of viscosity of isocyanate-terminated PTMEG prepolymers prepared by reacting a stoichiometric excess of one or more di- or polyisocyanates with PTMEG, comprising substituting for from 5 equivalent percent to about 50 equivalent percent of PTMEG with one or more ultra-low unsaturation polyoxypropylene diols having molecular weights in the range of about 1500 Da to about 20,000 Da and an average unsaturation of less than about 0.010 meq/g.
A process for the preparation of a segmented polyurethane/urea spandex elastomer, comprising reacting in solution in a solvent:
- a) an isocyanate-terminated prepolymer prepared by reacting a stoichiometric excess of one or more di- or polyisocyanates, so as to provide a free NCO group content of said prepolymer of from about 0.5% by weight to about 10% by weight based on prepolymer weight, with a polyol component comprising in most major part a diol component, said diol component comprising from about 5 equivalent percent to about 50 equivalent percent of one or more ultra-low unsaturation polyoxypropylene diols having a molecular weight in excess of about 1500 Da and an average unsaturation of less than about 0.010 meq/g, and from about 95 equivalent percent to about 50 equivalent percent of one or more polytetramethylene ether glycols having a molecular weight of from about 600 Da to about 6000 Da;
- with
- b) a diamine chain extender comprising one or more aliphatic diamines, cycloaliphatic diamines, or mixtures thereof to form an aliphatic diamine and/or cycloaliphatic diamine chain extended spandex elastomer reaction product;
- and
- c) removing said solvent from said reaction product.
Dependencies are inferred from the claim text.