221 results about "Reactive extrusion" patented technology

The invention relates to a crosslinked polymerized composition, comprising a crosslinker comprising a —Sn— moiety and having at least two polymerizable groups, wherein n is an integer of from 2 to 8, and one or more polymers. The invention also relates to methods of making a reversibly-crosslinked polymer by reacting the components of the polymerized composition via a reactive extrusion process, resulting in reversibly-crosslinked polymer having dynamic crosslinks.

The invention provides a preparation method and application of a dynamic covalent bond compatibilized thermoplastic blend, and relates to the technical field of high polymer materials, the method comprises the following steps: (1) carrying out melt blending on at least two incompatible or partially compatible thermoplastic polymer blends, a reaction reagent containing acid anhydride or carboxyl groups, an initiator and an auxiliary agent according to a mass ratio of 100: (0.5-12): (0.05-1.5): (0.5-12), carrying out reactive extrusion to obtain a grafted modified material; and (2) carrying out melt blending on the grafted modified material, a cross-linking agent containing an epoxy group or a hydroxyl group and a catalyst according to a mass ratio of 100: (1-20): (0.1-5), and carrying out reactive extrusion to form a dynamic covalent bond network so as to obtain the compatibilization blend. According to the invention, the compatibility and mechanical properties of the thermoplastic blend are improved, and the problems of high recovery cost, complex recovery technology, serious plastic pollution and the like of the waste thermoplastic plastic blend in real life are solved.

In an embodiment, a polyurethane comprises the residues of i. an aliphatic diisocyanate, ii. an aliphatic diol comprising a poly(ethylene oxide) moiety, iii. an aliphatic diol comprising a polycarbonate moiety, and iv. a chain extender, wherein the polyurethane has a melting temperature of 140° C. or less and has a weight average molecular weight of from 100,000 to 500,000 g / mol. In an embodiment, the polyurethane is substantially devoid of catalyst. In an embodiment, the polyurethane is formed by reactive extrusion. In an embodiment, a medical device comprises the polyurethane and a bioactive agent. The medical devices, methods, and polyurethanes may exhibit benefits in end-product biostability, drug release profile, health and safety, and processing speed or reproducibility.

The invention provides an antistatic polypropylene material as well as a preparation method and application thereof, and belongs to the technical field of polypropylene materials. The preparation method comprises the following steps: modifying graphene, preparing a graphene / titanium dioxide compound, reacting, and performing extrusion molding. The method comprises the following reaction steps: putting a functionalized graphene / titanium dioxide compound into a reaction container, introducing N, N-dimethylformamide, uniformly stirring, adding modified graphene, dicyclohexylcarbodiimide and 4-dimethylaminopyridine, heating to 73-77 DEG C, carrying out ultrasonic treatment, and after ultrasonic treatment is finished, carrying out heat preservation stirring for 1.8-2.2 hours to obtain the graphene / titanium dioxide composite material. Then heating to 116-123 DEG C at the speed of 1.7-2.3 DEG C / min, stirring for 1.8-2.2 hours while keeping the temperature, after stirring is finished, filtering, washing, freeze-drying, and naturally recovering to room temperature, so as to obtain a graphene-graphene / titanium dioxide compound; the antistatic polypropylene material prepared by the invention is good in antistatic property, excellent in mechanical property and good in aging resistance.

Cellulose / urea-formaldehyde water-retaining slow-release fertilizer granules prepared by means of a polycondensation-grafting-crosslinking integrated reaction extrusion process and an application method thereof. In a double-screw reaction extruder, low-polymerization-degree urea-formaldehyde undergoes a polycondensation reaction to generate urea-formaldehyde having a relatively high molecular weight, and under the strong shearing action of the extruder, cellulose having a large number of exposed active hydroxyl groups undergoes a nucleophilic substitution or condensation reaction, so that urea-formaldehyde macromolecules generated in situ are grafted onto macromolecular chains thereof; and -COOH of citric acid and -OH of cellulose simultaneously undergo a cross-linking reaction. By means of the polycondensation-grafting-crosslinking three-in-one reaction extrusion process, a cellulose / urea-formaldehyde compound is generated, thereby obtaining the cellulose / urea-formaldehyde water-retaining slow-release fertilizer granules in one step. By modifying urea-formaldehyde with hydroxyethyl cellulose, the strong intermolecular and intramolecular hydrogen bonding can enhance the mechanical properties of the urea-formaldehyde fertilizer, and the long molecular chains and abundant hydrophilic groups can also significantly improve the water absorption and water retention performance of the fertilizer.

The present invention relates to the technical field of nonmetallic compounds, and in particular to a reaction-extrusion preparation process and fertilization method for a weathered coal humic acid / urea-formaldehyde compound. In an alkaline environment, paraformaldehyde is depolymerized into formaldehyde small molecules and reacts with urea in a system to generate monomethylol urea and dimethylol urea. Then, under the strong shearing action of screws of a twin-screw reaction extruder, macromolecular weathered coal humic acid in the system is cracked into relatively small-molecular weathered coal humic acid to expose a large number of active groups of carboxyl, some of which are immediately subjected to dehydration-condensation reaction with amino on urea-formaldehyde molecules generated by polycondensation in the reaction-extrusion process in the system to generate a weathered coal humic acid / urea-formaldehyde compound, and particles of the weathered coal humic acid / urea-formaldehyde compound are obtained. The prepared compound particles have a high compressive strength, so that the breakage of fertilizer particles during storage, transportation and application can be avoided, and a fertilization and sowing integrated machine can be used to perform fertilization while sowing, thereby saving labor, time and fertilizers.

The invention relates to the technical field of high polymer materials, and discloses a preparation method of a modified master batch degradable material and application of the modified master batch degradable material in a packaging lunch box, and the modified master batch degradable material comprises the following components by mass: 75.0-93.8 parts of poly (butylene succinate); 5.0 to 20.0 parts of aliphatic series-aromatic copolyester; 1.0 to 4.0 parts of 1, 1 '-methylenebis-4, 1-phenylene-bismaleimide, and 1.0 to 4.0 parts of 1, 1'-methylenebis-4, 1-phenylene-bismaleimide; 0.5 to 2.0 parts of talcum powder; the method comprises the following steps: mixing dried poly (butylene succinate), aliphatic-aromatic copolyester, bismaleimide and talcum powder, performing reactive extrusion and melt mixing through a twin-screw extruder, and then cooling, pelletizing and drying the extrudate. Through specific components and a reactive extrusion process, a dynamic cross-linked network is formed by utilizing a Diels-Alder reaction, and the modified master batch degradable material of which the comprehensive mechanical property and the heat resistance are remarkably improved is prepared.

The invention belongs to the technical field of polymer composite materials, and discloses a large-scale preparation method of a PPS-based composite material with low expansion and high dimensional stability. According to the method, a multi-scale synergistic enhancement system of graphene and nano silicon dioxide is constructed, a maleic anhydride grafted PPS compatilizer is introduced into melt blending, and interface chemical anchoring is achieved through amino-maleic anhydride-epoxy ternary reaction. The filler is premixed according to the mass ratio of 1: 1 after being subjected to surface functionalization, the total content is 15-30 wt%, and the composite material is obtained through twin-screw reactive extrusion and injection molding. The invention provides the large-scale preparation method of the low-expansion high-dimensional-stability PPS-based composite material which is reasonable in structural design, high in process controllability, excellent in performance index and suitable for industrial production, and the problem that thermal expansion suppression and interface strengthening are difficult to consider at the same time in the prior art is solved.

The invention relates to the technical field of multi-layer material preparation, in particular to a high-light-transmittance weather-proof impact-resistant striped sound insulation board. The problem that transparency, weather resistance and sound insulation effect of a traditional stripe material are difficult to consider at the same time is solved. The light scattering and absorption center is reduced and high transparency and low haze are realized through reactive extrusion of the recycled material, combination of high-temperature adsorption activated carbon, multi-stage high vacuum and deep purification of a reactive decolorizing agent, and matching of transparent dispersion diffusion master batch and a compatilizer. The surface layer adopts the core-shell weather-resistant master batch and the secondary high-energy UV fluorosilicone curing coating for double shielding of ultraviolet and inhibition of photodegradation and yellowing; styrene-maleic anhydride damping resin is introduced into the middle layer, and uniform inclined micropores and asymmetric stripes formed by supercritical CO2 are combined, so that the medium and low frequency sound insulation index is improved; the bottom layer is repaired and guaranteed to be durable in impact resistance by virtue of a core-shell toughening agent and molecular chain extension; the defects of traditional products are overcome, and the service life requirement of sound barriers for expressways and rail transit is met.

The invention discloses a modified polypropylene composite material as well as a preparation method and application thereof, and belongs to the technical field of high polymer materials, and the modified polypropylene composite material is prepared by introducing a surface-activated two-dimensional functional filler, constructing a multiphase toughening system, designing a unique interface self-adaptive dynamic cross-linked network and combining a supercritical carbon dioxide assisted reactive extrusion process. And the technical bottlenecks of the traditional polypropylene composite material in the aspects of dimensional stability, rigidity-toughness balance and multifunctional integration are systematically solved. The composite material prepared by the invention has extremely low molding shrinkage rate (lower than 0.1%), excellent mechanical properties, efficient halogen-free flame retardance (UL-94V-0 level) and controllable antistatic performance. The preparation method is scientific in technological process and high in in-situ reaction efficiency, the efficient, continuous and green preparation process is achieved, and the method has remarkable industrial application value in the high-end fields of new energy automobiles, precision electronics, rail transit and the like.

The invention belongs to the field of high polymer materials. The invention provides hydrophobic modified polyester PET and a preparation method thereof, the hydrophobic modified polyester PET comprises the following components: polyester PET resin, an organic fluorosilicone-allyl glycidyl ether hydrophobic modification copolymer and an antioxidant, the preparation method of the hydrophobic modified polyester PET is also provided, the components are uniformly mixed according to the proportion to obtain a mixed material, and the mixed material is subjected to extrusion molding to obtain the hydrophobic modified polyester PET. Wherein the copolymer for hydrophobic modification of the organic fluorosilicone-allyl glycidyl ether is added in a form of being dissolved in an organic medium to form a polymer solution; and standing the mixed material for 1-2 hours, adding the mixed material into a double-screw extruder, carrying out melting reaction and extrusion, and removing and recovering the solvent and unreacted residual monomers in the raw materials through a vacuumizing exhaust device to prepare the hydrophobic polyester PET. The hydrophobic modified polyester PET is good and lasting in hydrophobic property, simple in preparation process and relatively low in cost, and can be applied to multiple fields such as textile and clothing, packaging materials, building materials, electronic and electric appliances, automobile manufacturing and the like.

The invention relates to the technical field of high polymer materials, and discloses a PVC (polyvinyl chloride) pipe for communication wiring and a preparation method thereof, and the pipe is prepared from polyvinyl chloride resin, a calcium-zinc composite heat stabilizer, stearic acid, polyethylene wax, maleic anhydride grafted polyethylene, an acrylate processing aid, nano calcium carbonate and an active lubricating precursor. The active lubricating precursor is a mixture formed by compounding amino-terminated polysiloxane and zinc stearate through heating and swelling. The preparation method of the PVC pipe for communication wiring comprises the steps of pre-preparation of the active lubricating precursor, multi-stage temperature-control high-speed mixing and reactive extrusion molding. Through in-situ chemical reaction of amino-terminated polysiloxane and maleic anhydride grafted polyethylene in the extrusion process, chemical anchoring of lubricating molecules is realized, the problem of precipitation of a lubricant is solved, and meanwhile, the lasting smoothness, impact strength and dimensional stability of the inner wall of the pipe are improved by cooperating with nano calcium carbonate.

The invention belongs to the technical field of polymer materials and electric wires and cables, and discloses a high-toughness cable composite material and a preparation method and application thereof. The preparation method comprises the following steps: (1) adding silane-terminated liquid polybutadiene, hydroxyl silicone oil and an organic tin catalyst into an anhydrous solvent, uniformly mixing, heating to 80-100 DEG C, carrying out dealcoholization condensation reaction, and evaporating to remove the solvent after the reaction is completed, so as to obtain an organic silicon modified polybutadiene cross-linking agent; and (2) adding the obtained organic silicon modified polybutadiene cross-linking agent, PE, EVA, a reinforcing filler and an initiator into an extruder in an oxygen-free atmosphere, carrying out melt blending cross-linking reaction, and carrying out extrusion molding to obtain the high-toughness cable composite material. Compared with a conventional vinyl silane cross-linking agent, the organic silicon modified polybutadiene cross-linking agent disclosed by the invention can remarkably improve the mechanical strength, flexibility and weather resistance of the obtained cross-linked polyethylene composite material.

The invention belongs to the technical field of photovoltaic adhesive film anti-aging, and provides an EVA photovoltaic adhesive film anti-aging auxiliary agent and a preparation method and application thereof.The EVA photovoltaic adhesive film anti-aging auxiliary agent is prepared through the steps that after a certain amount of peroxide initiator, a reaction type hindered amine light stabilizer containing carbon-carbon double bonds and EVA resin are evenly mixed, the mixture is extruded, and the EVA photovoltaic adhesive film anti-aging auxiliary agent is obtained; and reacting and extruding in a double-screw extruder to obtain the product. The preparation method of the anti-aging auxiliary agent for the EVA photovoltaic adhesive film provided by the invention is simple, mass production can be realized, and the anti-aging performance of the EVA photovoltaic adhesive film prepared by adopting the anti-aging auxiliary agent for the EVA photovoltaic adhesive film is remarkably improved.

The invention relates to the technical field of phenolic resin, and discloses a reactive extrusion device for continuously preparing phenolic resin, which comprises a horizontal reactor, the horizontal reactor is connected with a melt gear pump, the melt gear pump is connected with a reaction devolatilization extruder, the horizontal reactor is provided with a liquid feeding machine, and the liquid feeding machine is connected with the reaction devolatilization extruder. The reaction devolatilization extruder is provided with a powder feeding machine, the reaction devolatilization extruder is provided with a vacuum device and a template, and the reaction extrusion process for continuously preparing the phenolic resin comprises the following steps: S1, adding phenol and formaldehyde into the horizontal reactor, and uniformly mixing; s2, vacuumizing the output end of the horizontal reactor by using the vacuum device while the step S1 is carried out; s3, the melt is conveyed to the reaction devolatilization extruder; s4, a multi-stage vacuum system of the reaction devolatilization extruder is started, meanwhile, the powder feeding machine is started, and sodium hydroxide is added; and S5, the melt is subjected to devolatilization operation, and finally extrusion is completed through a template.

The invention relates to the technical field of high polymer materials and flame retardance, in particular to application of an efficient viscous compound material in oxygen barrier flame retardant materials, flame retardant polyolefin with hydroxyl is added into a high-shear twin-screw extruder, nano layered silicate and a reactive high polymer tackifier are sequentially added for reactive extrusion after melting, and the flame retardant polyolefin is obtained. And adding a micron-sized inorganic flame retardant and a carbon aid to the downstream of an extruder for blending, and finally cooling and pelletizing through an underwater pelletizing system to obtain the high-efficiency viscous compound material. According to the invention, a chemical bonding compatibilizing and toughening system is constructed through in-situ reaction of maleic anhydride grafted polypropylene and epoxy group functionalized SEBS, and complete stripping of nano-montmorillonite is realized by combining a step-by-step extrusion process, so that the problem that the mechanical property and flame retardance of a traditional high-filling flame-retardant material are difficult to consider at the same time is solved; the material has high limit oxygen index, high carbon residue rate and excellent tensile property, and the oxygen barrier layer is endowed with excellent mechanical toughness.

According to an example aspect of the present invention, there is provided a method for converting a plant material to a hardenable biomass by means of a reactive extrusion in a series of extrusion modules, which exposes carbohydrate compounds of the plant material.

This invention discloses an aqueous dispersion of a polyhydroxyalkanoate-grafted ethylene-acrylic acid copolymer with a self-emulsifying core-shell structure, its preparation method, and its recyclable paper packaging, belonging to the field of reactive modification of polymer materials and green packaging technology. This invention employs in-situ reactive extrusion technology to construct stable microparticles with a hydrophobic polyhydroxyalkanoate core and a hydrophilic ethylene-acrylic acid copolymer salt as the shell, overcoming the industry challenge of poor compatibility of bio-based materials. The aqueous dispersion requires no external emulsifier, achieving the same excellent barrier and heat-sealing effects with a lower coating weight, significantly reducing usage costs. Its unique alkali-induced swelling mechanism endows the coating with intelligent peeling properties, achieving efficient separation of the coating and fiber during resizing, greatly improving the purity of recycled fibers.

The present invention relates to a method for preparing esterified flour as resistant starch, through cross-linking by esterification process through hot air oven and alternative method (reactive extrusion), comprising the steps of: for hot air oven, preparing acid aqueous solution; adding flour into the solution; incubating, and drying the slurry in hot air oven to get esterified flour; and washing the flour, and the resistant starch processed by the method thereof and for reactive extrusion, preparing and mixing flour with citric acid aqueous solution; reactively extruding the dried mixed flour; feeding the extruded dried mixed flour; adjusting a screw rotation speed of the extruding machine; stabilizing the weight of the starch citrate extrudate; grounding and sieving the stabilized starch citrate extrudate; and removing unreacted citric acid, and the neutral acid-base resistant starch citrate product processed by the method thereof. The purpose of the invention is to produce resistant starch citrate classified as resistant starch type 4 (RS4) to improve the digestion-resistant property of flour to be the key ingredient of the food helping develop the world food products, in the manufacturing scale, to have properties beneficial to health, as well as to add value to plant- based flour products.

The invention discloses a PC / PET composite material which comprises the following components in parts by weight: 50-60 parts of PC, 15-35 parts of PET, 2-10 parts of graphene, 10-12 parts of mineral powder, 0-6 parts of a flexibilizer, 0.1-1 part of a lubricant and 0.1-0.5 part of an antioxidant, and the mineral powder is modified by a silane coupling agent, methanol and an acid solution. The invention also provides a preparation method and application of the PC / PET composite material. According to the PC / PET composite material and the preparation method and application thereof provided by the invention, PC, PET, mineral powder and graphene with different molecular weight distributions are adopted for reactive extrusion, and a ball milling process is combined, so that the heat conductivity coefficient of the PC / PET composite material is improved, and the balance of rigidity and toughness is kept.

The application relates to the technical field of cable material manufacturing, and discloses a light-weight flexible wear-resistant electrical equipment connecting cable, a sheath of the connecting cable being made of raw materials including the following: polyester type thermoplastic polyurethane elastomer, styrene-acrylonitrile copolymer, maleic anhydride grafted polyolefin elastomer, blocked isophorone diisocyanate, wear-resistant premixed solution containing a catalyst, slow-release foaming master batch and functional additives; wherein the wear-resistant premixed solution containing the catalyst contains hydroxyl-terminated polydimethylsiloxane and a bismuth octoate catalyst, the slow-release foaming master batch contains modified azodicarbonamide foaming agent and carrier resin, and the functional additives contain antioxidants and carbodiimide hydrolysis stabilizers. According to the application, the hydroxyl-terminated polydimethylsiloxane containing the catalyst and the blocked isocyanate are introduced into the polyurethane matrix in cooperation through a reaction extrusion process, the isocyanate groups are unblocked at high temperature, and the organic silicon chain segment is chemically bonded with the matrix resin.

The invention relates to the technical field of high polymer materials, in particular to a pumice powder modification-based linear low-density polyethylene master batch and a preparation method thereof. The problem that an existing pumice powder modified polyethylene master batch is poor in aging resistance when being used for preparing a film is solved. The master batch disclosed by the invention is prepared from linear low-density polyethylene resin, pumice powder modified by KH-560 and a light stabilizer 944, activated nano zinc oxide, maleic anhydride grafted polyethylene, polydimethylsiloxane, a composite antioxidant and zinc stearate. During preparation, the modified pumice powder and the activated nano zinc oxide are prepared through hydrolytic condensation and loading processes, and then the linear low-density polyethylene master batch is obtained through high-speed premixing and twin-screw reaction extrusion granulation. Finally, a film prepared from the linear low-density polyethylene master batch has good aging resistance.

The invention discloses a preparation method of starch plastic with low surface energy and high hydrophobicity. The thermoplastic starch plastic comprises the following components in percentage by weight: 73% of starch, 21.8-24.5% of lactic acid and 2.7-5.5% of bleached shellac. The preparation method comprises the following steps: uniformly mixing starch, lactic acid and bleached shellac according to a certain ratio, and preparing the thermoplastic starch plastic by a reactive extrusion (single-screw or double-screw extruder) method. The thermoplastic starch plastic has excellent water resistance, the lowest surface energy of the thermoplastic starch plastic can reach 38.41 mJ / m < 2 >, the maximum surface water contact angle of the thermoplastic starch plastic can reach 90.7 degrees, and the purpose of hydrophobicity of the thermoplastic starch plastic is achieved; in addition, compared with traditional glycerin plasticized thermoplastic starch plastic, the tensile strength can be improved by 3-7 times, certain elongation at break can be kept, and the mechanical property is also remarkably improved.

The present invention discloses a high-performance and easily processable TPU particle and its preparation and storage methods. The preparation method includes the steps of: (1) adding polyol, isocyanate, and chain extender into a reactive extruder, controlling the temperature of the reaction zone of the reactive extruder at 140-180 °C, and side-feeding a catalyst in the penultimate temperature zone of the reactive extruder; (2) the product extruded by reaction in step (1) is cooled, pelletized and enters a silo, the temperature of the silo is controlled at 0-20 °C, and a nucleating agent is side-fed inside the silo, and after mixing, the high-performance and easily processable TPU particle is obtained. The storage method: storing the high-performance and easily processable TPU particle at a constant temperature of 0-22 °C. The TPU particle of the present invention is obtained by low-temperature processing, and can significantly expand the controllable temperature range and reduce energy consumption in subsequent extrusion processing. More importantly, the products processed and manufactured have higher strength.

The application belongs to the field of TPU colorants, and specifically provides a preparation method of a TPU special macromolecular colorant, comprising the following steps: 1) taking oligomer dihydric alcohol, colored dihydric alcohol, chain extender, and isocyanate for standby; 2) uniformly mixing the oligomer dihydric alcohol, the colored dihydric alcohol, the chain extender, and the isocyanate, then reacting and extruding in a double-screw extruder, and then cooling, granulating, and drying to obtain the TPU special macromolecular colorant. The TPU special macromolecular colorant prepared by the application has the advantages of good compatibility, good dispersibility, good migration resistance, and high gloss.

The invention relates to a crosslinked polymerized composition, comprising a crosslinker comprising a –Sn– moiety and having at least two polymerizable groups, wherein n is an integer of from 2 to 8, and one or more polymers. The invention also relates to methods of making a reversibly-crosslinked polymer by reacting the components of the polymerized composition via a reactive extrusion process, resulting in reversibly-crosslinked polymer having dynamic crosslinks.

The invention discloses a corrosion-resistant and mildew-proof wood-plastic floor and a processing method thereof, and relates to the technical field of wood-plastic floors, the processing method comprises the following steps: carrying out refined pretreatment on wood powder to obtain fine wood powder meeting the requirements of particle size and dryness; the method comprises the following steps: pretreating a plastic base material through recycled polyethylene plastic particles, removing impurities and adjusting the particle size of the particles; an epoxy functional mildew preventive is synthesized in situ and is used for forming covalent bonding with a wood-plastic matrix subsequently; mixing the pretreated plastic base material, the wood flour and the epoxy functional mildew preventive in sequence to obtain a uniform material; bonding and plasticizing of the materials are achieved through a reactive extrusion process, and a molten profile is formed; carrying out on-line shaping and gradient cooling on a molten profile obtained by reactive extrusion, eliminating internal stress, and carrying out curing molding; and fixed-length cutting and finish machining are conducted on the sectional material subjected to gradient cooling and curing, and the finished corrosion-resistant and mildew-proof wood-plastic floor is obtained.

The invention relates to the technical field of cable insulation materials, in particular to an anti-aging chemical crosslinked polyethylene cable insulation material and a preparation process thereof. The insulating material is prepared from the following components in parts by mass: 50 to 60 parts of low-density polyethylene, 20 to 25 parts of polyolefin elastomer, 10 to 15 parts of maleic anhydride grafted SEBS (Styrene-Ethylene-Butylene-Styrene), 1.5 to 2.5 parts of dicumyl peroxide, 15 to 20 parts of composite flame-retardant filler and 3 to 5 parts of anti-aging composition, the preparation process comprises the following three steps: firstly, preparing the core-shell structure flame-retardant master batch of zinc borate coated talcum powder through ball milling and melt blending; secondly, mixing the anti-aging component with a polyolefin elastomer to prepare an anti-aging master batch; and finally, mixing the matrix resin with the two master batches and the cross-linking agent, carrying out reactive extrusion in a four-section temperature zone (150-195 DEG C), and carrying out water-cooling cutting and drying to obtain a finished product. The insulating material has the characteristics of no toxicity, long-term high temperature resistance, aging resistance and excellent flame retardance, and is suitable for low-voltage to medium-voltage power cables.

The application provides a kind of open-cell foamed polypropylene material and preparation method, and the preparation method of open-cell foamed polypropylene material includes: polypropylene is reacted with first initiator extrusion to obtain low molecular weight polypropylene;Low molecular weight polypropylene is mixed with polypropylene according to preset ratio, second initiator, grafting monomer, antioxidant and the like are melt grafted to obtain short branched chain structure polypropylene;After short branched chain structure polypropylene is foamed, open-cell foamed polypropylene material is obtained.The scheme of the application utilizes low molecular weight polypropylene and grafting monomer to graft together on polypropylene molecular chain, improves the foaming performance and open-cell structure of polypropylene.

The application discloses acetoacetamide modified polyvinyl alcohol and a preparation method thereof, and the preparation method comprises the following steps: reacting p-ester and an acetoacetamide reagent at 20-80 DEG C for 1-3h in a polar solvent to generate N-acetoacetyl p-ester; then, the N-acetoacetyl p-ester is mixed with an alkaline catalyst and polyvinyl alcohol, and is added into a double-screw reaction extruder to generate N-acetoacetyl p-ester modified polyvinyl alcohol crude product; finally, the crude product is powdered, washed with methanol for three times to remove the catalyst and reaction inorganic salt, and is filtered and dried to obtain the N-acetoacetyl p-ester modified polyvinyl alcohol. The AAE-PVA prepared by the application can be used as a protective colloid for polyvinyl acetate emulsion polymerization, has better water resistance than common polyvinyl alcohol, and the water resistance, tensile strength and stability of the prepared emulsion adhesive are obviously improved. The synthesis steps of the application are simple, the safety risk is low, and the reaction yield is high.