45results about How to "Reduce melt viscosity" patented technology

The invention belongs to the technical field of modification of ultra-high molecular weight polyethylene, and particularly relates to special resin for a modified ultra-high molecular weight polyethylene lining oil pipe and a preparation method of the special resin. The special resin for the modified ultra-high molecular weight polyethylene lining oil pipe is prepared from the following raw materials in parts by mass: 65 to 80 parts of ultra-high molecular weight polyethylene, 5 to 10 parts of high-density polyethylene, 8 to 12 parts of modified polyaryletherketone, 4 to 7 parts of modified hyperbranched polyester, 0.3 to 2 parts of silicone master batch and 0.1 to 0.5 part of antioxidant. The lining oil pipe prepared from the special resin for the modified ultra-high molecular weight polyethylene lining oil pipe has excellent wear resistance and high temperature resistance, and also has good mechanical properties such as tensile strength and impact strength.

The invention discloses a glass fiber reinforced halogen-free flame-retardant high glowing filament PBT (polybutylene terephthalate) modified material and a preparation method thereof, and the glass fiber reinforced halogen-free flame-retardant high glowing filament PBT modified material comprises the following components in parts by weight: 28.5-44.5 parts of PBT resin, 0-10 parts of PET (polyethylene terephthalate) resin, 18-25 parts of a compound of organic hypophosphite and inorganic hypophosphite, 5-14 parts of a glowing filament synergist and 1-5 parts of a modified toughening agent, the invention relates to the technical field of high polymer materials, in particular to a high polymer material which comprises the following components in parts by weight: 0.1-0.5 part of an anti-transesterification agent, 0.2-1 part of an antioxidant, 0.2-1 part of a lubricant and 15-30 parts of glass fibers. The glowing filament has high mechanical properties and good fireproof performance, can meet the market demand that the glowing filament at 750 DEG C is not ignited in the whole process, meets the latest environment-friendly control requirement on the market, and has wide market application prospects.

The invention discloses low-temperature curing high-toughness polyester resin as well as a preparation method and application thereof, and relates to the technical field of high-molecular polymer materials. The polyester resin is prepared from the following raw materials: a prepolymer A, a prepolymer B and an end-capping reagent, the prepolymer A is a hydroxyl-terminated prepolymer containing one or more cycloalkyl groups; and the prepolymer B is a carboxyl-terminated prepolymer containing a borneol structure. The polyester resin has relatively low melt viscosity and relatively high glass transition temperature, is good in leveling property and flexibility, can realize low-temperature curing and is suitable for preparing a powder coating, and the obtained powder coating not only has low-temperature curing performance, but also has relatively low cost compared with a conventional polyester powder coating obtained by low-temperature curing. The leveling property, the flexibility and the storage stability can be considered, and the better comprehensive performance is achieved. The powder coating is particularly suitable for coating thermosensitive substrates, such as substrates such as wood and plastic.

This utility model discloses an injection mold for manufacturing control panel housings, relating to the field of control panel housing manufacturing technology. The utility model includes a mounting frame providing installation and stable support for the device, a vibration mechanism housed within the mounting frame, and a demolding mechanism for vibrating the mold during injection molding. Specifically, the vibration mechanism involves a motor driving the front rotating shaft to rotate, while a pulley system simultaneously drives the rear rotating shaft to rotate synchronously. Two impact wheels jointly strike the bottom of the lower mold, causing it to vibrate. During vibration, the lower mold, through the mounting plate, compresses the damping rod and spring, which work together to buffer the vibration and reduce violent shaking. This vibration mechanism reduces the viscosity of the molten plastic, promotes uniform filling of the cavity, assists demolding, simplifies the mold structure, and reduces cost and maintenance difficulty.

The invention discloses a polypropylene film suitable for a film lamination method and a preparation method of the polypropylene film. The polypropylene film comprises the following components in parts by weight: 85.6-91.85 parts of polypropylene; 4-7 parts of long-chain branched polypropylene; 4-7 parts of a compatibilizer; 0.05 to 0.1 part of a nucleating agent; and 0.1 to 0.3 part of an antioxidant. Firstly, polypropylene is selected, so that the wettability of a melt to carbon fibers is effectively improved, and the filling defect caused by high viscosity of a traditional material is overcome; and secondly, the compatibilizer is introduced to form firm chemical bonding with the fiber surface, so that the interface bonding strength is greatly enhanced. And finally, by combining a precise extrusion and casting process, the prepared polypropylene film is uniform in thickness, excellent in interface performance and suitable for a film lamination method.

The application discloses an ultrahigh-molecular-weight polyethylene silicon nano wear-resistant composite pipe and a preparation method thereof, and relates to the technical field of ultrahigh-molecular-weight polyethylene composite pipes. The ultrahigh-molecular-weight polyethylene silicon nano wear-resistant composite pipe is prepared from the following raw materials in parts by mass: 70-85 parts of ultrahigh-molecular-weight polyethylene, 5-15 parts of silicon nano particles, 3-6 parts of maleic anhydride grafted polyethylene, 0.1-1.2 parts of a silane coupling agent, 1-3 parts of a wear-resistant reinforcing agent, 0.3-1.5 parts of a lubricant and 0.3-1 part of an antioxidant. The surface of the silicon nano particles is modified by using a specific silane coupling agent, and the silicon nano particles are effectively combined with the ultrahigh-molecular-weight polyethylene matrix, so that the dispersibility of the nano particles in the polymer matrix is solved, and the wear resistance and the mechanical properties of the pipe are remarkably improved.

The invention belongs to the technical field of high polymer materials, and discloses a polyvinyl alcohol composition and a preparation method thereof, and a polyvinyl alcohol film and a preparation method thereof, the composition contains polyvinyl alcohol, a plasticizer, a melt flow modifier and a stabilizer; the content of the polyvinyl alcohol is 65 to 85 parts by weight, the content of the plasticizer is 12 to 30 parts by weight, the content of the melt flow modifier is 2.5 to 4 parts by weight, and the content of the stabilizer is 0.5 to 1 part by weight. The composition disclosed by the invention can meet the requirements of melt extrusion and continuous two-way stretching, the polyvinyl alcohol film can be rapidly prepared, and the film is excellent in performance.

The invention relates to the technical field of polymer composite material processing, and discloses a polyphenyl ether modified EVA (Ethylene Vinyl Acetate) hot melt adhesive and a preparation method thereof. The hot melt adhesive is prepared from the following components in parts by weight: 35 to 50 parts of EVA (Ethylene Vinyl Acetate) resin, 5 to 20 parts of polyphenyl ether, 30 to 60 parts of tackifying resin, 5 to 20 parts of wax and 0.4 to 0.8 part of composite antioxidant. EVA and PPE in a specific ratio are selected as base materials (wherein EVA is the main base material), and a proper amount of tackifying resin is added into the system to modify the EVA hot melt adhesive, so that the melt viscosity of the system is reduced, the cohesion of the hot melt adhesive and the wettability of the hot melt adhesive on a bonding interface are improved, the bonding strength is enhanced, and the performance is further improved; the tackifying resin is low in volatile matter, and the softening point of the tackifying resin is higher than that of EVA resin, so that the softening point of the hot melt adhesive can be further improved, and the low-temperature resistance, mechanical property and ageing resistance of the hot melt adhesive are improved.

The application relates to the technical field of high-molecular heat-conducting composite materials, and particularly discloses a low-thermal-resistance grafted modified polyethylene material and a preparation method thereof.The low-thermal-resistance grafted modified polyethylene material comprises polyethylene resin, alpha-olefin ethylene copolymer, polar grafting monomer, initiator, modified sheet-shaped heat-conducting filler, spherical heat-conducting filler, composite antioxidant and functional additive.The modified sheet-shaped heat-conducting filler and the functional additive are compounded and added into a polyethylene matrix through a specific formula, the components interact with each other, the filler agglomeration is effectively inhibited, and the interface combination is strengthened, so that the heat transfer efficiency in the resin is significantly improved under the premise of not excessively increasing the filler amount, the obtained grafted modified polyethylene material successfully breaks through the bottleneck that traditional heat-conducting polyethylene is difficult to simultaneously consider heat conduction, mechanics and processing performance, and finally exhibits the comprehensive characteristics of high heat conductivity, excellent mechanical strength and good melt flowability.

The present application relates to the field of hot melt adhesives, and in particular to a hot melt adhesive and a preparation method thereof. A hot melt adhesive, in parts by mass, comprises raw materials including: 5 to 12 parts of polyolefin elastomer, 40 to 60 parts of amorphous plastomer, 25 to 40 parts of tackifying resin, 10 to 20 parts of modified particles, 1 to 3 parts of antioxidant, 5 to 15 parts of lubricant, 1 to 5 parts of softener, 1 to 4 parts of cross-linking agent, and 1 to 2 parts of initiator. The hot melt adhesive prepared in the present application not only has good adhesion and mechanical properties for difficult-to-bond substrates such as PP / PE, but also can maintain its own excellent aging resistance, corrosion resistance, and waterproof and moisture resistance, meeting the existing automotive industry application requirements for the performance diversity of hot melt adhesives, and has very excellent application prospects in the automotive field.

A tough polyester heat shrinkable film that is not prone to brittle fracture and a preparation method thereof, belonging to the technical field of polymer packaging materials, the specific formula of the polyester heat shrinkable film is composed of pure polyethylene terephthalate, diol-modified polyethylene terephthalate, polybutylene terephthalate, toughening-crystallization nucleation composite agent, crystallization accelerator, opening smoothing agent, and filler. The polyester heat shrinkable film obtained by the present invention has a thickness of 31.1~51.6μm, a tensile strength TD193~202MPa, MD23~85MPa, an elongation at break TD26~52%, MD352~466%, a shrinkage TD 47~80%, MD0~15%, a haze of 4.2~5.0%, a light transmittance of 86.5~87.4%, and no significant decrease in elongation at break after being placed in a normal temperature and humidity environment for 24 months and a high temperature and high humidity environment for 18 days.

The application discloses a siloxane grafted hyperbranched polyethylene and application thereof in preparation of a low-leakage paraffin-based heat-conducting phase change material. The application provides a siloxane grafted hyperbranched polyethylene, which is obtained by copolymerization of ethylene and vinyltriethoxysilane according to a 'chain walking' polymerization mechanism and catalyzed by a Pd-diimine catalyst. The application provides application of the siloxane grafted hyperbranched polyethylene in preparation of a low-leakage paraffin-based heat-conducting phase change material. The application synthesizes the siloxane grafted hyperbranched polyethylene with crosslinking characteristics, uses the same to be compounded with paraffin, and forms a three-dimensional network structure through subsequent crosslinking, thereby effectively restricting macroscopic flow of paraffin above a phase change temperature, and significantly improving shape stability and anti-leakage performance of the composite material. Meanwhile, flake graphite is introduced to construct an efficient heat-conducting path, and the overall heat-conducting coefficient of the material is improved.

A method for recycling waste polyester, in particular to a method for recycling waste polyester by a modified alcoholysis method to recycle waste polyester to prepare dimethyl terephthalate (DMT), is provided and belongs to waste polyester recycling technology field. The waste polyester after dewatering and deoxygenation treatment is used as a raw material, in the step of feeding in melted state the alcoholysis agent is added in the melted waste polyester for preliminary alcoholysis, and the alcoholysis agent is ethylene glycol. On one hand, alcoholysis reaction occurs when the waste polyester raw material are melted, and at the same time, the viscosity of the melted material is reduced. Thus, the melted material remains melted at the alcoholysis temperature and is not easy to solidify again after entering the alcoholysis tank, ensuring that the alcoholysis is carried out under homogeneous conditions.

The invention relates to the technical field of high polymer materials, in particular to a preparation method of a chlorinated polyvinyl chloride modified material, which is prepared by chlorination of polyvinyl chloride by a chemical grafting method, block of 2-ethylhexyl acrylate and grafting of dodecenyl succinic anhydride. Net-shaped cross-linked block chlorinated polyvinyl chloride prepared by cross-linking acrylonitrile fibers and poly-alpha-methyl styrene through a physical blending method is used, and long-chain fatty acid ester containing active proton pellet groups is grafted on chlorinated paraffin to serve as a main stabilizer. The molecular structure of the obtained chlorinated polyvinyl chloride modified material is more excellent, and the strength, the thermal stability and the heat resistance of the chlorinated polyvinyl chloride modified material are greatly improved; the impact-resistant chlorinated polyvinyl chloride improves the self-defect of poor impact resistance of chlorinated polyvinyl chloride, obviously improves the plasticity, widens the application range, and is especially suitable for preparation of heat-resistant and impact-resistant high polymer material products.

The invention relates to a lubricating auxiliary for ABS resin and a preparation method thereof, belonging to the technical field of plastic processing. The lubricating auxiliary comprises, by weight, 50 parts of a lubricating main agent, 25-35 parts of a calcium-based auxiliary agent and 15-25 parts of a dispersant; wherein the lubricating main agent is prepared by amine ester exchange between a dialkylamine and diethyl diallylmalonate to prepare an amide compound with alkyl chain modification, namely, intermediate 1; then, mercaptoethanol is subjected to click addition with double bonds in the intermediate 1 molecule to introduce a thioether structure and a terminal active primary alcohol into the intermediate 1 molecule to obtain intermediate 2; finally, single-ended epoxy silicone oil is ring-opened with an alcohol hydroxyl grafted in the intermediate 2 to introduce silicone oil chain modification to obtain the lubricating main agent; the lubricating auxiliary has both internal and external lubricity for ABS plastics and solves the problem of strength reduction of ABS products caused by lubricants.

The present application belongs to the technical field of electrolytic synthesis of non-ferrous metals and alloys, and discloses a method for preparing ferrotitanium alloy by electrolyzing ilmenite or high-titanium slag in a boron-containing molten oxide system. A titanium raw material is mixed into a B2O3-CaO-CaF2-SiO2 system after dehydration to form a melt; the melt is placed in a crucible and put into a sealed reactor; a cathode and an anode are put in, and a certain distance is kept between the two, and inert gas protection is provided; the temperature is raised to the working temperature, and electrolysis is carried out for a certain time; the product is taken out after cooling, washed with dilute acid and distilled water, and dried. The addition of B2O3 to the CaO-CaF2-SiO2 system for high-temperature molten oxide electrolysis can accelerate the dissolution of TiO2 in ilmenite and high-titanium slag, reduce the melting point of the molten salt, increase the migration rate of titanium ions, reduce the melt viscosity, and significantly improve the dissolution efficiency of TiO2 and the efficiency of electrolytic titanium.

The utility model discloses a kind of tensile tear-resistant reinforced CPVC cable protection pipe, it includes pipeline, the inside fixed connection of pipeline has CPVC resin, the inside fixed connection of CPVC resin has nano calcium carbonate, the inside fixed connection of nano calcium carbonate has calcium-zinc stabilizer.Through the above structure, there is a layer of CPVC resin in pipeline, the smooth surface of CPVC resin can reduce the contact area of cable and pipe wall, reduce the local temperature rise caused by heat generation due to friction, while the air gap between pipe wall and cable is more uniform, beneficial to the heat dissipation of cable operation, prolong the service life of cable, there is also a layer of nano calcium carbonate in it, nano calcium carbonate particle size is usually 10~100nm, specific surface area is large and dispersibility is good, uniformly filled in CPVC resin matrix can form "rigid particle reinforcing effect", the tensile strength of inner wall layer is improved by 20%~30%, and bending modulus is improved by 15%~25%.

The invention provides silane modified polyethylene for blow molding. The silane modified polyethylene is prepared from the following raw materials in parts by weight: 65-97.3 parts of polyethylene resin; 1-30 parts of a filler; 0.5 to 5 parts of unsaturated diacid; 1 to 11 parts of hydroxyl terminated polydimethylsiloxane; and 0.2 to 2 parts of a peroxide initiator. Double bonds of unsaturated diacid are grafted to a polyethylene molecular chain in a reactive extrusion process under the action of free radicals decomposed by a peroxide initiator; meanwhile, carboxyl of unsaturated diacid can react with hydroxyl of hydroxyl polydimethylsiloxane to form an ester group, and polydimethylsiloxane becomes a flexible branch chain, so that the branching degree of a polyethylene molecular chain is greatly improved, the melt strength is enhanced, and the processing requirements of rapid and large blow molding products can be met.

The invention provides a glass fiber reinforced polypropylene material and a preparation method thereof, and belongs to the technical field of propylene copolymers. The preparation method comprises the steps of maleic anhydride copolymer preparation, polypropylene pretreatment, glass fiber pretreatment and blending. The method for preparing the maleic anhydride copolymer comprises the following steps: adding maleic anhydride, styrene and azodiisobutyronitrile into methylbenzene, heating to 70-90 DEG C in a nitrogen environment, stirring and reacting for 1-2 hours at the current temperature, adding glycidyl acrylate, continuously reacting for 30-50 minutes, naturally cooling, filtering, washing and drying to obtain the maleic anhydride copolymer. According to the glass fiber reinforced polypropylene material, the tensile strength is 32-35 MPa, the elongation at break is 71-75%, and after a thermal aging test, the tensile strength is 29-33 MPa, and the elongation at break is 65-70%.

The present invention relates to a method for preparing polylactic acid for producing a matte biaxially stretched film in the field of polylactic acid materials. A matting agent is added before the ring-opening polymerization reaction of polylactic acid and its copolymer, and then polylactic acid and its copolymer are prepared by ring-opening polymerization of lactide and comonomer under polymerization conditions. The polylactic acid and copolyester resin materials obtained after the polymerization have good film-making stability and excellent matting performance. The raw material components and their weight parts are as follows: 100 parts of lactide and comonomer, 0.3-5 parts of matting agent, 0.01-0.4 parts of initiator, 0.5-2 parts of antioxidant, and 0.1-3 parts of catalyst. The present invention adopts a method of physically blending a matting agent with a monomer raw material, improves the dispersibility of the matting agent, and the matting degree is convenient to control. Polylactic acid and its copolymer can obtain a film material with high haze, low gloss and good matting effect after biaxial stretching.

The invention discloses a highly flame-retardant foaming modified styrene thermoplastic elastomer and a preparation method thereof, which belongs to the field of materials, and the raw materials for preparation include thermoplastic elastomer, polyolefin, solvent oil, macromolecular flame retardant, foaming agent, foaming promoter and crosslinking agent; the macromolecular flame retardant is polyphosphinosilazane; the solvent oil includes cycloalkane oil and epoxy soybean oil; the epoxy soybean oil modifies the foaming agent to obtain the epoxy soybean oil modified foaming agent; the epoxy soybean oil modified foaming agent is then mixed with thermoplastic elastomer, polyolefin, cycloalkane oil, polyphosphinosilazane, foaming promoter and crosslinking agent to obtain the highly flame-retardant foaming modified styrene thermoplastic elastomer. The macromolecular flame retardant in the invention is halogen-free and non-toxic and can form an interpenetrating network structure with the molecular chain of the matrix material, improve the compatibility with the matrix, significantly improve its flame retardant properties, and can also improve its impact strength and resilience.

The invention discloses a method for preparing a high temperature resistant flame retardant radio frequency coaxial cable. The high temperature resistant flame retardant radio frequency coaxial cable comprises a conductor, an insulating layer, a shielding layer and a sheath layer. The sheath layer comprises the following raw materials in parts by weight: 40 to 60 parts of polyvinyl chloride resin, 10 to 15 parts of EVA resin, 5 to 8 parts of glass fiber, 3 to 5 parts of expansion flame retardant, 0.5 to 2 parts of synergistic flame retardant, 4 to 6 parts of kaolin, 0.1 to 0.5 parts of coupling agent, and 1 to 3 parts of plasticizer. , 0.5 to 2 parts of lubricant, and 0.1 to 0.5 parts of antioxidant. The present invention prepares an intumescent flame retardant rich in P and N by polycondensing 5-nitrofurfural and ethylenediamine with hypophosphorous acid, and obtains a synergistic flame retardant used in combination with chitosan phosphate after ZIF-8 is adsorbed with chitosan phosphate and hyperbranched polysiloxane is grafted on the surface thereof. The sheath layer and the high-temperature resistant and flame-retardant radio frequency coaxial cable having the sheath layer have excellent flame retardant properties through the compounding of the intumescent flame retardant and the synergistic flame retardant.

This invention discloses an enhanced antistatic polyetheretherketone (PEEK) composite material and its preparation method. The composite material is prepared from the following raw materials in parts by weight: 60-85 parts of PEEK resin, 5-15 parts of a first synergistic component, 3-10 parts of a second synergistic component, 2-8 parts of a third synergistic component, and 1-5 parts of a high-temperature processing aid. The first synergistic component is a mixture of a metal-based conductive filler and a high-temperature resistant antistatic synergist; the second synergistic component is ionic liquid-functionalized modified graphene; the third synergistic component is a composite of carbon nanotubes and conductive nanofibers; and the high-temperature processing aid includes a high-temperature lubricant and a high-temperature antioxidant. The preparation method includes steps such as preparing various premixes, melt blending, extrusion granulation, and supercritical fluid in-mold foaming. This invention constructs a stable three-dimensional conductive network through the synergistic effect of multi-scale conductive fillers, giving the composite material excellent antistatic properties.

The present invention provides an additive that improves moldability without impairing the heat resistance of heat-resistant resins, such as super engineering plastics, that have high melt viscosity, and that reduces melt viscosity and does not produce volatile components such as gas during molding. As a solution, the present invention provides an aromatic ether nitrile composition that contains a dihydroxy compound represented by general formula (1) and satisfies compositions (i) and (ii) in liquid chromatography (LC) analysis using ultraviolet light at a wavelength of 280 nm as a detector. Composition (i): the area percentage of the dihydroxy compound represented by general formula (1) is in the range of 10% or more and 95% or less relative to all components detected by the LC analysis. Composition (ii): the sum of the values of the area percentages of a compound represented by general formula (2), a dihalobenzonitrile compound represented by general formula (3), and a dihydroxy compound represented by general formula (4) is 5% or less relative to all components detected by the LC analysis.

The invention discloses an anhydride-cured epoxy resin bonding sheet, which comprises a base material, the thermal expansion adhesive layers are arranged on two sides of the base material, and the thermal expansion adhesive layer is characterized by consisting of multifunctional epoxy resin, an anhydride curing agent, a temperature-sensitive foaming agent, thermoplastic resin and an accelerant. According to the invention, acid anhydride is used as a curing agent, and the thermal expansion adhesive layer is solid at room temperature, so that the product can maintain low viscosity and good expansibility at high temperature while maintaining surface non-viscosity at room temperature, can improve the fluidity of the thermal expansion adhesive layer when heated, and has a favorable effect on thermal expansion of the thermal expansion adhesive layer; in addition, the anhydride curing agent is also beneficial to increasing the glass transition temperature (Tg) of the adhesive sheet and improving the heat resistance; and the price of the anhydride curing agent is relatively low.

The present invention belongs to the technical field of processing and manufacturing of polytetrafluoroethylene tubes, and specifically relates to a transparent polytetrafluoroethylene tube, a preparation method and an application thereof. The present invention adopts high compression ratio polytetrafluoroethylene and PFA to blend and extrude to form a transparent polytetrafluoroethylene tube, thereby improving the transparency of the transparent polytetrafluoroethylene tube; at the same time, a secondary sintering method is adopted to promote the fusion of high compression ratio polytetrafluoroethylene and PFA, which can not only improve the transparency of the transparent polytetrafluoroethylene tube, but also improve the strength and elongation of the transparent polytetrafluoroethylene tube. The transparent polytetrafluoroethylene tube provided by the present invention has an outer diameter of less than 5.0 mm and has a high transparency, and is suitable for use in medical devices.

The invention discloses a seamless welding broken bridge aluminum door and window heat insulation strip and a preparation method thereof, and relates to the technical field of organic materials. The invention discloses a preparation method of a seamless welding broken bridge aluminum door and window heat insulation strip, which is characterized by comprising the following steps: premixing an antioxidant, a lubricant, a grafting solubilizer, an automobile water tank recycled PA66 material and black sand according to the proportion of raw material components, adding PA10T resin and modified glass fiber, blending, extruding, granulating and drying to obtain an alloy material; and molding the alloy material to obtain the seamless welding broken bridge aluminum door and window heat insulation strip. The heat insulation strip prepared by the invention has the characteristics of excellent mechanical property and good temperature resistance.

The application belongs to the technical field of high polymer materials, and particularly relates to a PET-based long-acting antistatic master batch as well as a preparation method and application thereof. The application adopts HBP-IM and HOOC-PEG-COOH as comonomers, and anchors the antistatic active chain segment to the PET main chain through in-situ polycondensation reaction, so as to avoid the resolution and diffusion loss of the antistatic agent in the subsequent use or washing process. The hyperbranched structure provides sufficient free volume for the imidazole salt ion group, and cooperates with the effective passivation of trimethyl phosphate on the catalyst activity and the end capping of the carbodiimide on the carboxyl group, so as to jointly inhibit the ester exchange side reaction that may be intensified in the polycondensation process. The reaction process is precisely controlled through a stepwise reduced-pressure polycondensation program, the functionalized PET copolymer melt obtained from the polymer kettle is directly pumped into a double-screw extruder for blending and granulation in a molten state without cooling and granulation, and the hydrolysis and thermal cracking probability of the PET molecular chain in the secondary heating process is greatly reduced.

The invention provides a preparation method of a polyimide resin composite material. The preparation method comprises the following steps: preparing a polyimide resin solution; preparing the polyimide resin solution into a polyimide resin adhesive film; compounding the polyimide resin adhesive film with a reinforced fiber material to obtain a polyimide resin prepreg; a polyimide resin prepreg is laid on the laying mold, and a polyimide resin prepreg blank is obtained; carrying out first packaging and devolatilization treatment, and extracting reaction micromolecular products generated in the imidization process; and after secondary packaging, curing and molding, cooling and demolding to obtain the polyimide resin composite material. The polyimide resin composite material can be prepared through a vacuum bag forming technology, the dependence on forming equipment is reduced, and the manufacturing cost is greatly reduced.

The application belongs to the technical field of melt electrospinning equipment, and provides a screw-embedded self-viscosity-reducing melt electrospinning nozzle, which comprises a first inner sleeve, a second inner sleeve arranged outside the first inner sleeve, a first flow gap arranged between the first inner sleeve and the second inner sleeve, an outer sleeve arranged outside the second inner sleeve, a stirring part for stirring the melt in the first sleeve, and a motor for driving the screw to rotate. The melt in the first inner sleeve is stirred by the screw, and the melt is sprayed onto the nozzle cone surface through the second flow outlet under the action of pressure. The melt is subjected to twice physical actions, so that the viscosity of the melt is greatly reduced, and the functions of refining the fiber and improving the product quality are achieved.