Patent classifications
C08G18/18
Method for producing a resin lens from a polyisocyanate and release agent at reduced pressure
Provided is a method for producing a resin lens, comprising: A) mixing a polyisocyanate, a modified isocyanate, a catalyst and a release agent, and performing vacuum defoaming at 0˜30° C. for 10˜90 min to obtain a material a; B) mixing the material a with a sulfur-containing compound, and performing vacuum defoaming at 15˜20° C. for 20˜120 min to obtain mixed monomers; and C) completing casting of the mixed monomers, and curing to obtain a resin lens. The present disclosure uses polyisocyanate and a modified isocyanate at the same time to prepare a resin lens with higher glass transition temperature and higher surface hardness without producing bank mark and edge fogging. The present disclosure further provides a method for producing modified isocyanate. The obtained modified isocyanate used with polyisocyanate further improves the glass transition temperature and surface hardness of the resin lens without producing bank mark and edge fogging.
Catalyst system for polyol premixes containing hydrohaloolefin blowing agents
A catalyst system useful in the production of polyurethane and/or polyisocyanurate foams using hydrohaloolefin blowing agents.
PREPARATION OF POLYURETHANE SYSTEMS
The invention relates to a process for producing polyurethanes using a component A comprising a polyhydrazide, a polysemicarbazide, a polysulfonyl hydrazide and/or carbodihydrazide, in particular a polyhydrazide, wherein the component A is employed in the form of a mixture C which further comprises a component B comprising a dispersion medium.
FOAM WALL STRUCTURES AND METHODS FOR THEIR MANUFACTURE
Foam wall structures and methods for making them are described. The wall structures include a frame, a foam panel overlying a front surface of the frame, and a polyurethane foam layer disposed in a cavity of the wall structure. The polyurethane foam layer has a density, as determined by ASTM D1622-14, of at least 44 kg/m.sup.3 and exhibits ASTM E84-16 Class A flame spread and smoke development characteristics. The polyurethane foam layer is the cured reaction product of a polyurethane foam-forming composition that includes a polyisocyanate, an aromatic polyester polyol having a functionality of greater than 2.5 and an OH number of at least 300 mg KOH/g, which is present in an amount of at least 50% by weight, based on the total weight of the polyurethane foam-forming composition less the weight of the polyisocyanate, a catalyst, and a blowing agent composition. The blowing agent composition includes water and a hydrofluoroolefin.
HFO-CONTAINING ISOCYANATE-REACTIVE COMPOSITIONS, RELATED POLYURETHANE FOAM-FORMING COMPOSITIONS, AND SPRAY-APPLIED POLYURETHANE FOAMS
Isocyanate-reactive compositions that include a hydrofluoroolefin blowing agent, polyurethane foam-forming compositions, as well as spray-applied polyurethane foams formed therefrom that can provide structural support to wall structures and can also exhibit ASTM E84-16 Class A flame spread and smoke development characteristics at a foam thickness of 4 inches.
ISOCYANATE-REACTIVE COMPOSITIONS, POLYURETHANE FOAMS FORMED THEREFROM, MULTI-LAYER COMPOSITE ARTICLES THAT INCLUDE SUCH FOAMS, AND METHODS FOR THEIR PREPARATION
Isocyanate-reactive composition that include a polyol blend, a blowing agent composition, and a catalyst. The polyol blend includes a polyether polyol having a functionality of 2 to 6 and an OH number of 20 to 50 mg KOH/g, which is present in an amount of at least 30% by weight, based on total weight of the isocyanate-reactive composition, and an aromatic polyester polyol having a functionality of 1.5 to 3 and an OH number of 150 to 450 mg KOH/g, which is present in an amount of at least 40% by weight, based on total weight of the isocyanate-reactive composition. The blowing agent composition includes water, the water being present in an amount of 1 to 20% by weight, based on total weight of the isocyanate-reactive composition and in an amount of at least 90% by weight, based on total weight of the blowing agent composition. The isocyanate-reaction composition has a green content of at least 30% by weight, based on total weight of the isocyanate-reactive composition. Polyurethane foam-forming reaction mixtures, polyurethane foams, multi-layer composite articles and methods for their production are also described.
Preparation method for polyol and application of polyol in making polyurethane
A method for preparing a polyol comprises the following steps of: (1) dissolving 2,3 -epoxybutane and an acid catalyst in an inert solvent to obtain a solution A; dissolving triethylene glycol in an inert solvent to obtain a solution B; and dissolving epoxy vegetable oil in an inert solvent to obtain a solution C; (2) respectively and simultaneously pumping the solutions A and B into a first micromixer for mixing; (3) pumping the solution C and an effluent of the first microreactor into a second micromixer for mixing while carrying out step (2); and (4) dissolving the vegetable oil polyol in an inert solvent to obtain a solution D; dissolving epoxypropane and an alkaline catalyst in an inert solvent to obtain a solution E; and pumping the solution D and the solution E into a tank reactor for reaction, thereby obtaining the polyol.
POLYURETHANE FOAM PREMIXES CONTAINING HALOGENATED OLEFIN BLOWING AGENTS AND FOAMS MADE FROM SAME
The invention provides polyurethane and polyisocyanurate foams and methods for the preparation thereof. More particularly, the invention relates to closed-celled, polyurethane and polyisocyanurate foams and methods for their preparation. The foams are characterized by a fine uniform cell structure and little or no foam collapse. The foams are produced with a polyol premix composition which comprises a combination of a hydrohaloolefin blowing agent, a polyol, a silicone surfactant, and a precipitation-resistant metal-based catalyst used alone or in combination with an amine catalyst.
PRODUCTION OF RIGID POLYURETHANE FOAM
What is described is a composition for production of rigid polyurethane foam, comprising at least one isocyanate component, a polyol component, optionally a foam stabilizer, optionally blowing agent, wherein the composition contains at least one catalyst that catalyses the formation of a urethane or isocyanurate bond, wherein the catalyst comprises salts of amino acid derivatives.
Polyurethane comprising graphene nano structure
Described herein is a cast elastomer including graphene nano platelets and a process for preparing the same.