1603 results about "Diphenylmethane diisocyanate" patented technology

A viscoelastic foam is produced by reacting (a) an isocyanate component that includes at least 25% by weight of diphenylmethane diisocyanate having a monomeric content of from 50 to 90% by weight, (b) an isocyanate-reactive component, (c) at least one catalyst, (d) at least one surface active agent, and (e) liquid carbon dioxide. These foams are characterized by a ball rebound of less than 20%. Particularly preferred foams are characterized by a 95% height recovery time greater than 4 seconds.

The invention discloses a partially blocked polyurethane curing agent and a preparation method thereof. The preparation method mainly comprises the following steps that end-NCO isocyanate prepolymer is obtained from the addition reaction of diphenylmethane diisocyanate and low-molecular polyol in ester solvent, and then the end-NCO isocyanate prepolymer reacts with isocyanate sealant to form the curing agent. The partially blocked polyurethane curing agent has the following characteristics that: a) according to the calculation of NCO by weight, the blocked-NCO content is between 1.0 and 5.0 percent; b) the solid content by weight of the curing agent is 75+/-2 percent, and the percentage content of the NCO by weight is between 12.0 and 13.0 percent (according to the calculation of the effective percentage of the NCO, the percentage content of the NCO including blocked NCO radicals); and c) the viscosity of the curing agent at 25 DEG C is between 1,500 and 2,500 mPa. s. The invention has the advantages of low toxicity, good storage stability, adjustable curing speed and the like.

A polyamide-imide resin insulating coating material, which is obtained by reacting an isocyanate component with an acid component, has a main solvent component of γ-butyrolactone. In the coating material, a total compounding ratio of 4,4′-diphenylmethane diisocyanate (MDI) and trimellitic anhydride (TMA) is 85 to 98 mol %, where the total compounding ratio is given by averaging a compounding ratio of MDI to the isocyanate component and a compounding ration of TMA to the acid component.

The invention discloses a novel high-strength polyurethane waterproofing paint which consists of a component A and a component B. The component A is prepared from the following components in parts by weight: 140-350 parts of polyether polyol, 20-60 parts of TDI (toluene diisocyanate), 20-60 parts of diphenylmethane diisocyanate and 50-100 parts of a plasticizer; the component B is prepared from the following components in parts by weight: 50-100 parts of polyether polyol, 40-200 parts of a plasticizer, 20-80 parts of a chain extender, 100-300 parts of pigment and filler, 0.1-0.5 part of a catalyst, 0.1-0.5 part of a polymerization inhibitor and 0.1-1 part of a high-performance accessory ingredient defoaming agent. The invention also comprises a preparation method of the high-strength polyurethane waterproofing paint. The high-strength polyurethane waterproofing paint disclosed by the invention has relatively long operable construction time and excellent physical and mechanical properties such as high strength, high elongation rate and high bonding strength, and is low in residual TDI and toxicity. The novel high-strength polyurethane waterproofing paint can be widely applied to infrastructure construction and municipal traffic engineering, and particularly to water resistance of important projects such as high-speed railways and highway bridges.

This invention relates to a method for distilling an isomer mixture of isocyanate. The method comprises: adding an isomer mixture of diphenylmethane diisocyanate into a separator, and distilling to obtain at least one product mixture, which comprises: 2,4'-MDI 50-60 wt.%, 4,4'-MDI 40-50 wt.%, 2,2'-MDI less than 1.5 wt.%, 2,4'-MDI less than 1 wt.%, and 4,4'-MDI greater than 99 wt.%. Compared with present distillation methods, the method has such advantages as saved distillation steps, reduced distillation column number, saved energy input, reduced isocyanate loss, and high 4,4'-MDI purity in the product mixture.

The invention discloses a single-component moisture-curing polyurethane adhesive and a preparation method thereof. The preparation method of the adhesive is characterized by comprising the following step: by adopting an organic solvent as a solvent, performing reaction on polyether glycol and/or polyester glycol, diphenyl methane diisocyanate, polymethylene polyphenyl isocyanate and triatomic primary alcohol of which the molecular weight is less than 200 to prepare the adhesive. The average degree of functionality of an obtained high-functionality NCO-terminated prepolymer is more than or equal to 3, and the single-component moisture-curing polyurethane adhesive disclosed by the invention is suitable for splicing and tenoning (or assembling) of woods and bonding and compounding of stone materials, fireproof plates, plastic aluminum plates, bakelite plates, oak boards, some metals such as aluminum and iron, zinc-plating plates, PVC membranes and the like, is especially suitable for adhesion of rosewoods and red woods, and can meet the special requirements of some products.

The invention belongs to the field of polyurethane adhesives, relates to coating adhesive for woodworking industry, in particular to a double-component polyurethane adhesive and a preparation method thereof. The double-component polyurethane adhesive is obtained by compounding a component A and a polyurethane component B containing an isocyanate-terminated group, wherein the component A is polyurethane synthesized by polyester polyol and diphenylmethane diisocyanate (MDI) as well as accessory ingredients; the polyurethane component B containing the isocyanate-terminated group is synthesized by polyester polyol and/or polyether polyol, isocyanate, epoxy resin and accessory ingredients. The double-component polyurethane adhesive disclosed by the invention is good in adhesion performance, high in early-stage bonding strength and final bonding strength, and good in heat resistance, does not bounce at 80 DEG C, and is colorless, low in smell and low in cost.

The invention provides a polyurea micro capsule and the preparing method thereof. The preparing method comprises the following steps:(1) Add the organic phase with diphenylmethane diisocyanate into the water phase which contains surface promoting agent and agitate, emulsificate to obtain the latex A; (2) Add the diethylenetriamine into the water solution which contains surface promoting agent to obtain the continuous phase solution B; (3) Add the continuous phase solution B into the latex A to rouse the interface polymerization reaction on the oil and water interface to obtain the suspension which contains the polyurea micro capsule. The method of the invention adopts the diphenylmethane diisocyanate and has a small toxicity and volatilization, and has small influence to the environment and the experiment operation. The invention can add the diethylenetriamine directly after the latex is formed; therefore the invention has quick and utterly reaction, a high efficiency and can reduce the cost. The invention adopts the one step directly reaction and the temperature can be controlled in room temperature; and the invention needs no other temperature rising, therefore the whole process has a low energy consumption.

The invention relates to a preparation method of a high-resilience urethane elastic fiber. The preparation method comprises the following steps: (1) mixing raw materials, namely, polytetramethylene ether glycol (PTMEG) and 4, 4-diphenylmethane diisocyanate (MDI) to carry out reaction so as to obtain a prepolymer; (2) adding a certain amount of a mixed diamine chain extender into the prepolymer to form polymer liquor; (3) quickly adding polyamine (the number of functional groups is greater than 2) into the polymer liquor while stirring to carry out reaction so as to form polyurethaneurea liquor; (5) carrying out reaction on MDI and polyether polyhydric alcohol and blocking with ethanediamine to prepare oligomers; (6) blending nano attapulgite with the oligomers to prepare a prepreg; and (7) mixing the polyurethaneurea liquor with the prepreg to prepare a spinning dope, and spinning to form the high-resilience urethane elastic fiber. The preparation method of the high-resilience urethane elastic fiber provided by the invention satisfies the demands on the high-resilience urethane elastic fiber in certain special fields, and the resilience of the urethane elastic fiber is improved.

The invention discloses an environment-protective polyurethane composition of indoor playground, which consists of component A and component B, wherein the component A contains basic component and organic bismuth catalyst; the basic component is composed of polyether polyol, filler, crosslinking agent, plasticizer, pigment, age resister and ultraviolet absorber; the component B concludes methane diphenyl diisocyanate (MDI)and polyester polyol; the blending rate of component A and component B is 2-5: 1 evenly, which are paved and solidified to produce the product without TDI, MOCA and DOP. The invention is superior to international index of runway, which is especially for paving indoor playground.

The invention relates to a polyurethane patching material used for settlement repairing of a ballastless structure for a high-speed railway. The polyurethane patching material is formed by hybrid reaction of an A component material and a B component material by a high-pressure impact. The volume ratio of the A component and the B component is 1:1-1:1.8. The A component is a mixture formed by polyhydric alcohol modified diphenylmethane diisocyanate and multi-methylene multi-phenyl isocyanate. The viscosity of the A component ranges from 100 mPa.s to 200 mPa.s at the 25 DEG C temperature. The B component is a mixture formed by polyhydric alcohol, a coupling agent, a hydrolytic stabilizing agent, a cross-linking agent, a foam stabilizing agent, a catalyst agent and a foaming agent. The viscosity of the B component ranges from 150 mPa.s to 300 mPa.s at the 25 DEG C temperature. The B component is characterized in that at least a part of end amido polyolefin polyhydric alcohol with 8 functionalities is in the polyhydric alcohol, and the content of the end amido ranges from 60%-80%. According to the polyurethane repairing material, the chemical reaction speed is high, the expansibility is high, the mechanical strength is high, the binding power is high, the size stability is high, the anti-hydrolysising property is good, and the deformation of accumulated residues is low. The polyurethane repairing material can be used for the settlement repairing of the ballastless structure for the high-speed railway, and can also be used for the pavement structure repairing of an expressway and the settlement repairing of an industrial building terrace.

The invention relates to a curing agent, namely, 4, 4 (1)-diphenylmethane diisocyanate prepolymer and a preparation method thereof. The method comprises the steps that molten 4, 4(1)-MDI and an organic solvent are added into a reaction vessel, and stirred uniformly, the temperature is raised to 65 DEG C, polyhydric alcohol dehydrated through evacuation is added, to react for 2 to 4 hours at 60 to 100 DEG C, and then an MDI modifier is produced; when being stirred, the mixed liquor of trimethylol propane and the organic solvent is titrated into the reaction vessel for 1 to 4 hour(s), the titration temperature is 60 to 100 DEG C, heat preservation and reaction are performed for 1 to 3 hour(s), then the temperature is raised to 90 to 100 DEG C and the heat preservation and the reaction are performed again for 1 to 4 hour(s), the temperature is reduced, and the organic solvent is added for dilution to appropriate viscosity. The curing agent has the advantages that the application scope is broad, the molecular structure of the polyhydric alcohol can be adjusted according to the requirements of users to produce the prepolymer of polyurethane coating, adhesive, and the curing agent, the storage stability is good, the curing speed is quick, the toxicity is low, the price is low, products with high solid content can be obtained, etc.

The invention discloses a preparation method of a bi-component siloxane modified polyurethane sealant, which belongs to the technical field of sealants. The method comprises the following steps: preparing a polyurethane prepolymer; carrying out synthetic reaction to obtain the polyurethane prepolymer under certain conditions by using two-function polyether glycol, diphenylmethane diisocyanate, plasticizer and siloxane containing amino groups; using the prepared prepolymer, inorganic filler, plasticizer and organosilicon adhesion accelerant as the first component of the sealant; and using inorganic filler, diluter, curing agent, surfactant, and dibutyltin dilaurate or tertiary amine catalyst as the second component. By designing the structure of the end silane polyurethane prepolymer and adjusting the proportion of the inorganic filler, in cooperation with a proper curing system and catalysis system, the prepared sealant has the characteristics of high curing speed, good adhesion effect and the like. The sealant has the advantages of high mechanical properties, good elasticity, no toxicity, no irritative gas emission and outstanding weatherability.

The invention relates to a polyurethane composition for preparing a polyurethane composite material. The initial viscosity of the polyurethane composition at 25DEG C is 10-600mPas. The composition comprises: a) a polyisocyanate component, wherein the polyisocyanate component includes 10-56wt% of 2,2'-diphenylmethane diisocyanate and 2,4'-diphenylmethane diisocyanate; and b) an isocyanate responsive component, wherein he isocyanate responsive component includes 30-100wt% of one or more glycerin-initiated polyether polyol, the hydroxyl value of the polyether polyol is 120-450mg KOH/g, and the viscosity of the polyether polyol is 50-450mPas. The invention also relates to a polyurethane composite material prepared by using the polyurethane composition, and a preparation method of the composite material.

The invention discloses the polyurethane hot melt adhesive for high-grade lining cloth, which is obtained through the reaction among polyester polyols with the relative molecular weight thereof being 2,000 to 2,200, 4,4-diphenylmethane diisocyanate (MDI), toluene diisocyanate (TDI), 1,4-butanediol (1,4-BDO) and aromatic diamine extender, wherein, the molecular weight of the polyurethane hot melt adhesive is 85,000 to 95,000. The polyurethane hot melt adhesive has the advantages of low thermal-bonding temperature and rapid crystallization, thereby facilitating the machining operations, preventing the polyurethane hot melt adhesive from being stuck to cloth and further preventing the polyurethane hot melt adhesive from penetrating and bleeding on ultra-thin loose base cloth; furthermore, the polyurethane hot melt adhesive has outstanding resistance to dry-cleaning and washing as well as washing under various caustic conditions. The invention further discloses a method for preparing the polyurethane hot melt adhesive for high-grade lining cloth.

The invention provides a method of preparing fluorinated polyurethane paint. The method is characterized by comprising the following steps: a step of preparing a component A, namely adding 15-60 parts of fluorinated polyether polyol and 0.01-0.03 part of dibutyltin dilaurate into a three-necked flask with a stirring rod in sequence, and stirring for 30 minutes to obtain the component A; a step of preparing a component B, namely adding 10-40 parts of 4,4-diphenyl methane diisocyanate and 0-30 parts of collaborative anticorrosive filler into 20-60 parts of a solvent system to stir and dissolve to obtain the component B; and a step of preparing fluorinated polyurethane anticorrosive paint, namely adding the component B into the three-necked flask filled with the component A, stirring for 8-10 minutes, grinding the mixed materials in the three-necked flask until fineness is 40-50 mu m after uniformly stirring, coating a metal sheet with the grinded mixed materials and curing for 24 hours to obtain the fluorinated polyurethane anticorrosive paint.

The invention discloses a preparation method and application of a heparan polyurethane blended modified polyethersulfone hollow fiber membrane. The preparation method is characterized by comprising the following steps of: adding 10 to 25 weight parts of diphenylmethane diisocyanate, 5 to 13 weight parts of dimethylolpropionic acid and 62 to 85 weight parts of solvent into a dissolving kettle, performing reaction for 4 to 12 hours at a temperature of 70 to 90 DEG C, washing the product with methanol and distilled water and drying to obtain carboxyl-containing polyurethane; adding 10 weight parts of polyurethane into 100 weight parts of concentrated sulfuric acid to carry out sulfonation to obtain polyurethane containing carboxyl and a sulfonic acid group; adding 1 to 10 weight parts of heparan polyurethane, 10 to 25 weight parts of polyethersulfone and 70 to 89 weight parts of solvent into the dissolving kettle to dissolve for 2 to 24 hours at a temperature of 75 to 95 DEG C so as to obtain hollow fiber membrane spinning dope; and preparing the hollow fiber membrane with excellent blood compatibility, permanent hydrophilicity, capacity of resisting to protein pollution and an anticoagulation function by adopting a dry spraying and wet spinning technology.