340 results about "Methylene diphenyl diisocyanate" patented technology

A process for the manufacturing of a core forming a carrying structure for decorative laminates. The core comprises particles of cured, and optionally foamed, rigid, polyurethane, polyisocyanurate and / or phenolic resin. The particles are bonded to each other in a pressing procedure with a bonding agent comprising an adhesive such as a polymerizing monomer.i) The particles are achieved by grinding cured, and optionally foamed, rigid, polyurethane, polyisocyanurate and / or phenolic resin so that it passes through a 2 mm screen, preferably a 1 mm screen,ii) 100 parts per weight of particles is mixed with 1-100 parts per weight of fiber, the fiber additive having an average length in the range 1-15 mm.iii) The particle-fiber mixture is allowed to absorb a selected amount of water, the amount of water being in the range 1-15% by weight, The water is either added at any stage before the adding of bonding agent, and / or being used as a solvent in the bonding agent, and that,iv) 85 parts per weight of the particle mixture is mixed with 2-15 parts per weight of a bonding agent, the bonding agent selected from the group consisting of,a) A mixture of polyols, such as polyester or polyether, crude methylene diphenyl diisocyanate and possibly a small amount of blowing agent in a ratio forming a polymeric resin with a density in the range 600-1400 kg / m3.b) A formaldehyde based resin such as phenol-formaldehyde resin, urea-formaldehyde resin, melamine-urea-formaldehyde resin, melamine-urea-phenol-formaldehyde resin or phenol-resorcinol-formaldehyde resin, orc) Polyvinyl acetate resin.v)The mixture is applied between the belts of the continuos belt press or the press plates of a static press, optionally with at least one intermediate carrier web, the belts or press plates allowing a mainly uniform and specified material thickness to form. A slightly porous and preconditioned core with a selected water content in the range 0.8-12% is hereby achieved. The invention also relates to a decorative laminate achieved through the process.

The invention provides a preparation method of methylene diphenyl diisocyanate. The method comprises the following steps: performing a salt forming reaction on m-xylylenediamine and hydrogen chloride gas to obtain m-xylylenediamine hydrochloride; mixing the m-xylylenediamine hydrochloride, an organic phosphorus compound and solid phosgene for reaction to obtain methylene diphenyl diisocyanate. In a process of preparing methylene diphenyl diisocyanate, according to the application, an organic phosphorus compound additive is introduced, so that the reaction of m-xylylenediamine hydrochloride is promoted, therefore, the reaction rate and the effective conversion rate are improved.

An encapsulated particle includes a core particle. The core particle includes a fertilizer selected from the group of nitrogen, phosphate, potash, and sulfur, and combinations thereof. The core particle may also include herbicides, insecticides, and fungicides. The encapsulated particle also includes a polyurethane layer disposed about the core particle. The polyurethane layer includes the reaction product of an aromatic isocyanate component and a polyol that is reactive with the aromatic isocyanate component. The aromatic isocyanate component includes methylene diphenyl diisocyanate, toluene diisocyanate, and mixtures thereof. The polyol that is reactive with the aromatic isocyanate component is derived from an aromatic amine-based initiator and includes a toluene diamine. The aromaticity of the aromatic isocyanate component and the polyol serves to insure complete miscibility between the aromatic isocyanate and the polyol thereby forming the polyurethane layer without defects preventing water from permeating the polyurethane layer and dissolving the core particle.

Process for preparing a flexible polyurethane foam comprising reacting at an isocyanate index of 70 to 130, 1) 40-65 parts by weight of a polyisocyanate composition comprising a) 80-100% by weight of a diphenylmethane diisocyanate component comprising, based on 100 parts by weight of the diphenylmethane diisocyanate component, i) 75-100 parts by weight of diphenylmethane diisocyanate comprising 15-75 parts by weight of 4,4′-diphenylmethane diisocyanate, and 25 to 85 parts by weight of 2,4′-diphenylmethane diisocyanate, and 2,2′-diphenylmethane diisocyanate and / or a liquid variant of such diphenylmethane diisocyanate, and ii) 0 to 25 parts by weight of homologues of diphenylmethane diisocyanates having an isocyanate functionality of 3 or more; and b) 20-0% by weight of toluene diisocyanate; 2) 20 to 45 parts by weight of a polyether polyol having an average molecular weight of 4500-10000, an average nominal functionality of 2-6 and comprising oxypropylene and optionally oxyethylene groups, the amount of oxypropylene groups being at least 70% by weight calculated on the weight of this polyol; 3) 3 to 20 parts by weight of a polyether polyol having an average molecular weight of 700-4000, an average nominal functionality of 2-6 and an hydroxyl value of at most 225 mg KOH / g and comprising oxyethylene and optionally oxypropylene groups, the amount of oxyethylene groups being at least 70% by weight calculated on the weight of this polyol; and 4) 2-6 parts by weight of water, wherein the amount of the polyisocyanate composition, polyol 2), polyol 3), and water being 100 parts by weight.

The invention discloses a micropore polyurethane elastomer material and a preparation method and use thereof. The micropore polyurethane elastomer material is composed of two components. The A component includes polyether polyatomic alcohol P1, polyether polyatomic alcohol P2, chain extension agents, foam stabilizers, water, tertiary amine catalysts and hollow glass microspheres by weight percentage. The B component comprises methylene diphenyl diisocyanate (MDI), TODI, and polyether polyatomic alcohol P1. P1 is selected from polytetrahydrofuran polyatomic alcohol with number-average molar mass as 1000-6000 and functionality as 2-3. P2 is selected from propylene oxide polythene oxide copolyether polyatomic alcohol with number-average molar mass as 2000-6000, functionality as 3-4 and primary hydroxyl content larger than or equal to 70%. The isocyanate index number of the A component and the B component is 1.1. The A component and the B component are prepared respectively, quickly and evenly mixed according to proportion, poured in a mould and solidified to obtain the micropore polyurethane elastomer which can be used as an elastic bearing plate of high speed railways.

The invention provides a spray rigid polyurethane foam heat insulation waterproof integrated material. The spray rigid polyurethane foam heat insulation waterproof integrated material is double-component foamed plastic which is formed by field spraying and consists of a component A and a component B in an equal volume ratio; the component A consists of 0 to 30 weight parts of toluene diisocynate, 0 to 30 weight parts of methylene diphenyl diisocyanate, and 70 to 100 weight parts of polymethylene polyphenyl isocyanate; the component B consists of 30 to 50 weight parts of polyatomic alcohol, 10 to 20 weight parts of catalyst, 5 to 10 weight parts of foam stabilizer, 10 to 30 weight parts of foaming agent, and 10 to 30 weight parts of fire retardant; the material comprises a foamed plastic layer with fire resistance, high intensity and density, and functions of watertightness, heat insulation, corrosion prevention, solvent resistance and the like; and the material can be mainly used for the watertightness, and heat insulation and the like of various roofs, wall bodies, and large-span light metal rooves with grid structures of industrial and civil buildings, and high-rise buildings, accessible rooves or roof gardens.

An encapsulated particle includes a core particle. The core particle includes a fertilizer selected from the group of nitrogen, phosphate, potash, and sulfur, and combinations thereof. The core particle may also include herbicides, insecticides, and fungicides. The encapsulated particle also includes a polyurethane layer disposed about the core particle. The polyurethane layer includes the reaction product of an aromatic isocyanate component and a polyol that is reactive with the aromatic isocyanate component. The aromatic isocyanate component includes methylene diphenyl diisocyanate, toluene diisocyanate, and mixtures thereof. The polyol that is reactive with the aromatic isocyanate component is derived from an aromatic amine-based initiator and includes a toluene diamine. The aromaticity of the aromatic isocyanate component and the polyol serves to insure complete miscibility between the aromatic isocyanate and the polyol thereby forming the polyurethane layer without defects preventing water from permeating the polyurethane layer and dissolving the core particle.