摘要:
The present invention relates to a sulfur-containing polyureaurethane and a method of preparing the polyureaurethane. The sulfur-containing polyureaurethane has a refractive index of at least 1.57, an Abbe number of at least 32 and a density of less than 1.3 grams/cm3 when cured. The sulfur-containing polyureaurethane is prepared by the reaction of: (a) a sulfur-containing, isocyanate functional polyurethane prepolymer derived from: (i) a polyisocyanate; and (ii) a polythiol oligomer produced by the reaction of at least two or more different dienes with one or more dithiols and in certain embodiments at least one trifunctional or higher-functional polythiol; and (b) an amine-containing curing agent.
摘要:
Sealant and potting formulations are provided which are prepared from components including ungelled mercapto-terminated polymer(s) prepared by reacting reactants comprising polyvinyl ether monomer(s) and polythiol material(s); curing agent(s) reactive with a mercapto group of the mercapto-terminated polymer; and additive(s) selected from the group consisting of fillers, adhesion promoters, plasticizers and catalysts.
摘要:
A polythioether includes a structure having the formula I —R1—[—S—(CH2)2—O—[—R2—O—]m—(CH2)2—S—R1—]n— I wherein R1 denotes a divalent C2-6 n-alkyl, C3-6 branched alkyl, C6-8 cycloalkyl or C6-10 alkylcycloalkyl group, —[(—CH2—)p—X—]q—(—CH2—)r—, or —[(—CH2—)p—X—]q—(—CH2—)r— in which at least one —CH2— unit is substituted with a methyl group, R2 denotes methylene, a divalent C2-6 n-alkyl, C2-6 branched alkyl, C6-8 cycloalkyl or C6-10 alkylcycloalkyl group, or —[(—CH2—)p—X—]q—(—CH2—)r—, X denotes one selected from the group consisting of O, S and —NR6, R6 denotes H or methyl, m is a rational number from 0 to 10, n is an integer from 1 to 60, p is an integer from 2 to 6, q is an integer from 0 to 5, and r is an integer from 2 to 10. The polythioether is a liquid at room temperature and pressure.