High impact poly (urethane urea) polysulfides
OwnerNina V. Bojkova, Vidhu J. Nagpal +3inventors
InventorsNina V. Bojkova, Vidhu J. Nagpal, Robert A. Smith, Marvin J. Graham, Michael O. Okoroafor
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Abstract
The present invention relates to a sulfur-containing polyureaurethane and a method of preparing said polyureaurethane. In an embodiment, the sulfur-containing polyureaurethane when at least partially cured can have a refractive index of at least 1.57, an Abbe number of at least 35 and a density of less than 1.3 grams/cm3. Further, the sulfur-containing polyureaurethane can be prepared by reacting a polyureaurethane prepolymer comprising a polycyanate and at least one hydrogen-containing material, at least one episulfide-containing material; and an amine-containing curing agent.
Claims76
A sulfur-containing polyureaurethane when at least partially cured having a refractive index of at least 1.57, an Abbe number of at least 35 and a density of less than 1.3 grams/cm3.
A method of preparing a sulfur-containing polyureaurethane comprising the steps of:
- (a) reacting a polyureaurethane prepolymer comprising a polycyanate and at least one hydrogen-containing material chosen from polyols, polythiols, and materials having both hydroxyl and thiol functional groups;
- (b) reacting said prepolymer with at least one episulfide-containing material;
- and
- (c) reacting mixture from step (b) with an amine-containing curing agent
- wherein when at least partially cured having a refractive index of at least 1.57, an Abbe number of at least 35 and a density of less than 1.3 grams/cm3.
An optical article comprising a sulfur-containing polyureaurethane, wherein said polyureaurethane when at least partially cured having a refractive index of at least 1.57, an Abbe number of at least 35 and a density of less than 1.3 grams/cm3.
A photochromic article comprising a sulfur-containing polyureaurethane, wherein said polyureaurethane when at least partially cured having a refractive index of at least 1.57, an Abbe number of at least 35 and a density of less than 1.3 grams/cm3.
A sulfur-containing polyureaurethane comprising the reaction product of:
- (a) a polyureaurethane prepolymer comprising a polycyanate and at least one hydrogen-containing material chosen from polyols, polythiols, and materials having both hydroxyl and thiol functional groups;
- (b) at least one episulfide-containing material;
- and
- (c) an amine-containing curing agent
- wherein when at least partially cured having a refractive index of at least 1.57, an Abbe number of at least 35 and a density of less than 1.3 grams/cm3.
Dependencies are inferred from the claim text.