Thermoplastic polyurethanes having a high heat stability, based on naphthylene diisocyanate, their production and their use

US4521582A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Wilhelm Goyert · Leverkusen, DE
• Jurgen Winkler · Schwarzheide, DE

Key dates

• Filing date: Aug 2, 1984
• Grant date: Jun 4, 1985
• Expiry date: Aug 2, 2004

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G18/10
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

This invention relates to novel, thermoplastically processible, branched polyurethanes based on naphthylene-1,5-diisocyanate which have good heat stability and are obtained by the claimed process. In the first stage of the process long-chain polyols are reacted with a first diisocyanate which is any diisocyanate other than naphthylene-1,5-diisocyanate in substoichiometric NCO quantities to produce an OH prepolymer which is then lengthened with excess napthylene-1,5-diisocyanate and with a chain lengthening mixture of short-chain diols and triols and/or polyols in specific ratios. The resulting semi-rigid, thermoplastic polyurethane elastomers are characterized by their good dimensional stability under heat, a good rebound elasticity (even at relatively high temperatures), acceptable low temperature flexibility and an outstanding resistance to wear which properties render them useful for the production of hydraulic seals, seals, rollers, buffers, tubes, bellows, plugs, cylinders, couplings and similar moldings.