The present disclosure relates to pyrrolidine-based catalysts for use in a polyurethane formulation. The polyurethane formulation includes the pyrrolidine-based catalyst, a compound containing an isocyanate functional group, an active hydrogen-containing compound. The use of such catalysts produces high quality polyurethane foam while reducing environmental concerns that can arise during the production of polyurethane foam as well as in in the foam that is produced.

A novel formulation for preparing a polyurethane foam with low density, desirable hardness, good appearance, and good adhesion to a polymer film without compromising the processing properties of the formulation; and a process for preparing a multilayer structure made of the polyurethane foam.

Embodiments of the present invention disclose a method for limiting peak exotherm temperatures in epoxy systems comprising the step of: combining an amine hardener, an epoxy and a diluent to form an epoxy system, wherein the diluent is selected from the group consisting of: ethylene carbonate, propylene carbonate, butylene carbonate, delta-valerolactam, delta-valerolactone, gamma valerolactone, butyrolactam, beta butyrolactone, gamma butyrolactone, and combinations thereof.

A process for the production of a lignin based polyurethane products is provided. The process comprises mixing at least one dried lignin and at least one isocyanate to form a lignin-isocyanate mixture, and submitting the lignin-isocyanate mixture to a polymerization reaction. The polymerization reaction may include heating the lignin-isocyanate mixture, adding at least one catalyst to the lignin-isocyanate mixture, or mixing the lignin-isocyanate mixture with a resin comprising at least one polyol, in the presence of at least one catalyst. The lignin based polyurethane products obtained by the process may be rigid foams, flexible foams, rigid boards, rigid blocks, coatings, packagings, adhesives, binders, sealants, elastomers, Thermoplastic Polyurethanes or Reaction Injection Moldings. There is also provided a mixture comprising at least one dried lignin and at least one isocyanate for use in the production of a lignin based polyurethane products.

The present invention provides a thermoplastic polyurethane obtained by reacting organic diisocyanate (A), polymer polyol (B) having a number average molecular weight (Mn) of 1000-5000 and chain extender (C), wherein the chain extender (C) contains a straight chain diol (c-1) and a side chain alkyl group-containing diol (c-2), a molar ratio of the straight chain diol (c-1) and the side chain alkyl group-containing diol (c-2) (straight chain diol (c-1)/side chain alkyl group-containing diol (c-2)) in the chain extender (C) is 97/3-60/40, and a nitrogen atom content is not less than 1.5 mass % and less than 4.0 mass %.

A process for producing an optical material of the present invention includes a step of mixing di- or higher-functional thiol compounds (A) having one or more sulfide bonds and/or one or more ester bonds with an imidazole-based curing catalyst (B) to prepare a mixed solution; a step of mixing the mixed solution with an isocyanate compound (C) including at least one kind of a di- or higher-functional alicyclic isocyanate compound (c1) and/or a di- or higher-functional aliphatic isocyanate compound (c2) to prepare a polymerizable composition for optical materials; a step of injecting the polymerizable composition for optical materials into a mold; and a step of polymerization-curing the polymerizable composition for optical materials in the mold.

The present invention can provide a method for producing a cured product of an episulfide-based resin, the method having: (A) a step for obtaining a composition for a resin by mixing compound (a), compound (b) and a polymerization catalyst; (B) a step for pouring the composition for a resin into a mold; and (C) a step in which, by increasing the temperature of a heating medium, the composition for a resin is polymerized in the heating medium that contains a liquid having a thermal conductivity of 0.2 W/m.Math.K or higher, or in a shower of the heating medium. The maximum temperature of the heating medium in step (C) is 55 to 110 C.

(a) A compound which has two episulfide groups per molecule and which is represented by formula (1):

##STR00001##

wherein m represents an integer from 0 to 4 and n represents an integer from 0 to 2 (b) A compound having one or more thiol groups per molecule.

A composition for the preparation of a transparent, non-elastomeric optical article is provided, the composition including: (1) a polyisocyanate component containing one or more different polyisocyanates; and (2) a component that is reactive with isocyanates, including: (a) optionally at least one polyol having a number average molecular weight greater than 500; (b) (i) at least one polyol and/or polythiol and (ii) at least one compound containing both amine and hydroxyl functional groups, wherein the compound (ii) has a number average molecular weight less than 500; and optionally (3) a urethanation catalyst. Multi-step and one-pot methods of preparing a cured, non-elastomeric polyurethane-containing optical article are also provided.

A molding composition including at least one semi-crystalline polyamide derived from the polyaddition of a) at least one polyamide prepolymer bearing n identical functions X chosen from carboxyl, amine and hydroxyl, and of b) at least one non-polymeric reactive extender bearing two identical functions Y that are reactive with said functions X with n ranging from 1 to 3, the polyamide and prepolymer a) including 55 mol % to 95 mol % of amide units A, 5 mol %-45 mol % of amide units B with A corresponding to x.T in which x is a linear aliphatic C9-C18 diamine and B corresponding to x.T in which x may be B1): specific branched aliphatic diamine dependent on x or B2): MXD or B3): linear aliphatic diamine which depends on x, the polyamide having a Tg of at least 90 C. and a Tm of less than or equal to 280 C.

The polymerizable composition for optical materials of the present invention includes: (A) a compound having a carbon-carbon double bond and at least one group selected from an isocyanate group and an isothiocyanate group in a molecule; and (B) a polythiol compound.