101results about How to "Uniform cell structure" patented technology

A two part system for producing structural reinforcing adhesives is provided wherein one component containing epoxy resin is combined with a second component containing a specified curative system. An aliphatic polyamine, an amidoamine, an alcohol and an adduct of a polyamine and an epoxide are present in the curative system. When a thermally activated blowing agent is utilized, the resulting foam is remarkably uniform in cell structure and has improved strength and modulus. Hollow inorganic microspheres are employed to reduce the density of the thermoset produced from the two part system.

The invention discloses graphene aerogel and a hybrid composite material thereof as well as a preparation method and application of the of graphene aerogel. The preparation method comprises the following steps: 1) mixing graphene oxide, a reducing agent, acrylamide, N,N-methylene-bisacrylamide and potassium persulfate and reacting to obtain partially-reduced graphene/polyacrylamide hydrogel; 2) carrying out pre-freezing and reduction on the partially-reduced graphene/polyacrylamide hydrogel in sequence to obtain graphene/polyacrylamide hydrogel; 3) dialyzing and drying the graphene/polyacrylamide hydrogel in sequence to obtain the graphene aerogel. The graphene aerogel has the characteristics of uniform cellular structure and light weight, excellent resilience, relatively high mechanical strength and good solvent resistance; a preparation process is simple, rapid and low in cost; the graphene aerogel can also be used for preparing polymer/graphene composite aerogel, nanoparticle/graphene composite aerogel and polymer/graphene composite materials and the like, so that application of the graphene aerogel is expanded.

The invention relates to a high oil absorption polyurethane foam which comprises the following components in parts by weight: 20 to 40 parts of isocyanate, 35 to 60 parts of polyol, 0.5 to 3 parts of catalyst, 0.5 to 3 parts of foam stabilizer, 5 to 10 parts of foaming agent, 2 to 10 parts of opening agent,5 to 20 parts of flame retardant, 5 to 15 parts of silicon rubber spherical micro powder and 0.5 to 2 parts of coupling agent. The preparation method comprises the following technology steps of weighing, prepolymerization, dispersing, polymerization foaming reaction, curing and peeling at room temperature and cutting. The high oil absorption polyurethane foam can be used for the absorption and recycle of various oil products (crude oil, engine oil, diesel fuel, gasoline, kerosene and the like) on water surfaces, ground or surfaces of other objects, and various oil soluble organic compounds (benzene, methylbenzene, dimethylbenzene, chloroform, nitrobenzene, chlorobenzene and the like). The invention has the advantages of simple technology and low cost, obviously improves the dispersing effect of the silicon rubber spherical micro powder in a polymerization system by using ultrasonic technique, and greatly increase the oil absorption quantity and oil absorption rate of the polyurethane foam by adding the silicon rubber spherical micro powder.

A polyol pre-mix composition includes a blowing agent having a halogenated hydroolefin, a polyol, a catalyst composition, and an antioxidant. The antioxidant may be, for example, a benzene diol or a benzene triol or other polyhydroxy-substituted aromatic compound, which is optionally substituted with one or more substituents such as alkyl groups. A two-part system for producing a thermosetting foam blend includes (a) a polyisocyanate and, optionally, one or more isocyanate compatible raw materials; and (b) the polyol pre-mix composition. A method for producing a thermosetting foam blend includes combining: (a) a polyisocyanate; and (b) the polyol pre-mix composition.

The invention relates to the field of rubber, and discloses vulcanized foam rubber and a preparation method thereof. The method comprises the following steps that (1) primary mixing is conducted on acomponent A containing a rubber base and a vulcanization activator; (2) secondary mixing is conducted on the primary mixed rubber and a component B containing a vulcanizing agent, a vulcanization accelerator and a foaming agent; (3) vulcanization is conducted on the secondary mixed rubber, wherein the vulcanization comprises three stages in sequence, the temperature of first stage vulcanization is100-170 DEG C, vulcanization pressure is 10-20MPa, and vulcanization time is 2-20min; and the second stage vulcanization is conducted under the condition that pressure of the first stage vulcanization is not changed, temperature of the second stage vulcanization is higher than the temperature of the first stage vulcanization, vulcanization time of the second stage vulcanization is shorter than that of the first stage vulcanization, the third stage vulcanization is conducted under the condition that the temperature of the second stage vulcanization is not changed, the pressure of the third stage vulcanization is lower than that of the second stage vulcanization, and the time of the third stage vulcanization is longer than the time of the second stage vulcanization. The vulcanized foam rubber prepared by the method is low in density and uniform in foam structure.

The invention discloses an epoxy resin modified polyisocyanurate high temperature-resistant rigid foamed plastic and a preparation method thereof. The high temperature-resistant rigid foamed plastic comprises a modified mixture and isocyanate, wherein the mass ratio of the modified mixture to the isocyanate is 1:(1.10-1.15); and the modified mixture comprises the following components by mass percent: 30%-35% of polyether glycol, 22%-27% of epoxy resin, 0.5-5% of foam stabilizer, 2-6% of catalyst and 32%-40% of foaming agent. The epoxy resin modified polyisocyanurate high temperature-resistant rigid foamed plastic is used for ideal uniform foam structures, and has excellent thermal stability at high temperatures, good product brittleness and thermal insulation performance, and excellent sound absorption performance and flame retardance.

The invention provides a yellowing-proof flexible polyurethane?foam and a manufacturing method thereof. The manufacturing method of the flexible polyurethane?foam is a manufacturing method allowing reaction of an organic polyisocyanate (A), a polyalcohol (B), a catalyst (C), a foaming agent (D) and a foam stabilizer (E) to form and to be solidified, so as to obtain the flexible polyurethane?foam. The manufacturing method is characterized in that the organic polyisocyanate (A) is mixture of the following substances: an allophanate group-containing organic polyisocyanate composition (A1) which is generated by a monohydric alcohol and an aliphatic and/or alicyclic diisocyanate, an allophanate group-containing organic polyisocyanate composition (A2) which is generated by a hydroxyl group-containing compound having more than two hydroxyl groups and an aliphatic and/or alicyclic diisocyanate, and an organic polyisocyanate compound (A3) which is generated by reaction of an aliphatic and/or alicyclic diisocyanate and a polyalcohol component (a1).

The invention relates to a hard polyimide foam material and a preparation method thereof, and belongs to the technical field of preparation of high-molecular polyimide foam materials. The preparationmethod comprises the steps of adding an aromatic dianhydride into a tetrahydrofuran/fatty alcohol mixed solvent, and conducting heating to dissolve the aromatic dianhydride; after the solution is transparent, adding an aromatic diamine for reaction to form a foam precursor solution, then adding a foam stabilizer and a foaming aid, and conducting uniform mixing; placing the solution in a drying oven to remove the solvent, and then raising the temperature to carry out primary foaming; and carrying out mold pressing on a primary foamed product to a compact state, further raising the temperature,and carrying out secondary foaming to obtain the polyimide foam. The method has the characteristics of low preparation cost, rich candidate raw materials, easiness in realizing large-scale productionand the like; and the prepared foam material has the characteristics of being uniform in foam structure, adjustable in apparent density, high in compressive strength, high in closed cell rate and almost free of slag falling.

Insulating foam composition for insulation on communication cables, contains 20-95 wt % of an unmodified propylene polymer, having a melt index of 0.1 to 10 g/10 min at 230° C./2.16 kg; and 5-80 wt % of a modified propylene polymer, with a propylene content of up to 100 wt %, and a melt index of 0.05 to 10 g/10 min at 230° C./2.16 kg. The unmodified propylene polymer is a propylene homopolymer; a propylene copolymer of propylene and ethylene or an alpha-olefin; a polyolefin mixture containing a crystalline copolymer of propylene and ethylene or an alpha-olefin, and an elastic copolymer containing ethylene and propylene or an alpha-olefin; or an amorphous, non-isotactic propylene polymer such as a propylene homopolymer, a propylene copolymer containing propylene and an alpha-olefin. The modified propylene polymer is a polypropylene modified by reaction with a bismaleimido compound, ionizing radiation, or a peroxide.

The invention discloses a halogen-free and flame-retardant composite polyimide foam material and a preparation method thereof. The foam material is prepared from raw materials in parts by weight as follows: 100 parts of aromatic dianhydride, 50-500 parts of a polar solvent, 5-30 parts of fatty alcohol, 5-20 parts of deionized water, 15 parts of a foam stabilizer, 5 parts of a composite catalyst, 4-100 parts of a halogen-free composite flame retardant and 100-500 parts of polyisocyanate. The preparation method comprises the steps as follows: aromatic dianhydride is heated in the polar solvent to react with fatty alcohol; the deionized water, the foam stabilizer, the composite catalyst and the halogen-free composite flame retardant are added, and a suspension is obtained; finally, polyisocyanate is added, foaming and vacuum heating curing are performed, and the flame-retardant polyimide foam material is obtained finally. The prepared foam material has the characteristics of low density, uniform pore size distribution, excellent mechanical property, heat resistance and flame-retardant and smoke-suppression performance and the like, and the requirement for the polyimide foam material used in aerospace, navigation and other high-end fields can be met.

The invention discloses a refuse lac chain-extended modification powder, which comprises the following compositions in parts by weight: 100 parts of refuse dehydrated lac and 5-13 parts of multi-epoxy compound chain extending agent; by adopting macromolecular multi-functional epoxy compounds as chain extending agents, the chain extension and/or crosslinking modification reaction can be realized by performing heating reaction to carried epoxy groups with shelloic acid in the refuse lac or carboxyl and/or hydroxyl in the condensation compounds, so that the molecular weight can be increased, and further the purpose of improving the melting point of the refuse lac and increasing the relative viscosity can be achieved, the refuse lac chain-extended modification powder with the melting point ranging from 75 DEG C to 104 DEG C can be prepared, the powder can keep the dissolvability in ethanol and aqueous alkali solution while the melting point and the relative viscosity are remarkably increased, thus providing physical basis for the follow-up use of the refuse lac, and being capable of promoting the recycling of the refuse lac.

The invention discloses low-cost flame-retardant polyimide heat insulation foam and a preparation method and application thereof. The preparation method comprises the following steps: S1, mixing a phosphorus-based liquid flame retardant and a polyol surfactant, adding a catalyst, and conducting an ester exchange reaction to synthesize a phosphorus-containing polyol flame retardant; S2, mixing a pyromellitic diester solution, a foam stabilizer, a compound catalyst and a foaming agent to obtain a foaming white material; S3, stirring and mixing the phosphorus-containing polyol flame retardant andisocyanate, and carrying out a room-temperature prepolymerization reaction to obtain a phosphorus-containing foaming black material; S4, stirring and mixing the foaming white material and the foamingblack material to a uniform state at a high speed to obtain foaming slurry; and S5, pouring the foaming slurry into an open mold, carrying out a free foaming molding process to obtain a polyimide foam intermediate, and curing the foam intermediate after the foam intermediate is shaped. The obtained polyimide foam has good flame retardant property and can improve safety performance and heat insulation performance, so that the polyimide foam can be used for preparing a wall heat insulation material.

A method for producing porous metal plated polymeric foam having uniform pore properties. Polymeric foam buns are horizontally cut along a longitudinal surface thereby lifting off a foam sheet. The sheet is spooled and then reticulated to remove any remaining cell walls and to round off the internal pore struts to enlarge the openings between the adjacent cells. The reticulated foam sheet is unwound and then plated. Slabs may be attached end to end and loop slitted and then reticulated. The resulting plated uniform foam provides a superior substrate for battery plaques and other applications.

The invention discloses a conductive fluorinated silicone rubber foam composite material, a preparation method thereof and application of the conductive fluorinated silicone rubber foam composite material in the field of gas-sensitive detection. The preparation method comprises the following steps: ultrasonically dispersing carbon conductive particles in an organic solvent which is volatile at normal temperature to obtain conductive particle dispersion liquid; stirring perfluorosilicone oil, hydrogen-containing fluorosilicone oil and conductive particle dispersion liquid in an organic solvent until the organic solvent is completely volatilized, then adding a foaming agent and an inhibitor, performing uniform mixing to obtain a component A, and uniformly mixing perfluorosilicone oil and a platinum catalyst to obtain a component B; mixing the component A and the component B, performing uniform stirring, reacting at room temperature for 5-30 minutes, and crosslinking and curing the obtained product at 50-125 DEG C for 10-60 minutes to obtain the conductive fluorinated silicone rubber foam composite material.