A kind of modified teflon material and preparation method thereofTechnical field
The present invention relates to organic resin material technical field, in particular to a kind of modified teflon material and its preparationMethod.
Background technique
Polytetrafluoroethylene (PTFE) (PTFE) is to be invented by U.S. Roy Joseph doctor Plunkett in 1938, E.I.Du Pont CompanyIt was had registered in 1945Trade mark, while being commercially produced.Polytetrafluoroethylene (PTFE) has excellentChemical stability, corrosion resistance, sealing property, high lubrication, non-stickiness, electrical insulation and good anti-aging endurance, can be -180Long-term work is resistant to various other chemicals in addition to molten metal sodium and liquid fluorine under DEG C low temperature to 250 DEG C of high temperature, even ifIt boils in chloroazotic acid and does not also change.
Since with above-mentioned many advantages, polytetrafluoroethyl-ne alkenes product has been widely used in chemical industry, machinery, electronics, electricityThe industries such as device, military project, space flight, environmental protection and bridge.In recent years, people constantly add the R&D intensity of polytetrafluoroethylene (PTFE) new materialGreatly, many new application fields are also quickly expanded, for some new fields, to the performance such as intensity etc. of polytetrafluoroethylene (PTFE)Requirements at the higher level are proposed, therefore, the property such as exploitation teflon based material new varieties, the intensity for promoting teflon based materialA current important research direction can be had become.
Summary of the invention
In view of this, the purpose of the present invention is to provide a kind of modified teflon material and preparation method thereof, this hairThe intensity of polytetrafluoroethylene (PTFE) can be substantially improved in the modified Teflon of bright offer, simultaneously, moreover it is possible to improve its electric conductivity and leadIt is hot.
The present invention provides a kind of modified teflon materials, are made by the raw material comprising following quality than component:
Preferably, the flash-point of the aviation kerosine is 38~60 DEG C.
Preferably, in the graphene micro mist, thickness≤2nm of graphene sheet layer, the mean outside diameter of graphene sheet layer is0.5~10 μm.
Preferably, the auxiliary agent is selected from one of toughener, anti-wear agent, extrusion aid, antistatic agent and lubricant or severalKind.
Preferably, the mass ratio of various auxiliary agents in the feed are as follows:
The present invention also provides a kind of preparation method of modified teflon material as described in the above technical scheme, packetsInclude following steps:
A) it by the mixing of polyflon, aviation kerosine, graphene micro mist and auxiliary agent and stewing process, is mixedMaterial；
B) high temperature compacting is carried out to the mixture, obtains compacting product；
Temperature >=145 DEG C of the high temperature compacting；
C) low temperature compacting and dry oil removing are carried out to the compacting product, obtains modified teflon material；
Temperature≤50 DEG C of the low temperature compacting.
Preferably, in the step a), stewing process is constant temperature stewing process；
The temperature of the constant temperature stewing process be 20~50 DEG C, the time be 12~for 24 hours.
Preferably, in the step b), the temperature of high temperature compacting is 145~165 DEG C；High temperature compacting pressure be 3~4.5MPa。
Preferably, in the step c), the temperature of low temperature compacting is 35~50 DEG C；The pressure of low temperature compacting is 3~6MPa.
Preferably, the step b) includes:
B1 precompressed) is carried out to the mixture, obtains material base；
B2 high temperature compacting) is carried out to the material base, obtains compacting product；
The precompressed is constant temperature precompressed, and the temperature of precompressed is 30~45 DEG C, and the pressure of precompressed is 0.3~1.5MPa.
The present invention provides a kind of modified teflon materials, are made by the raw material comprising following quality than component: poly-Tetrafluoroethylene resin 70%~90%, aviation kerosine 5%~20%, graphene micro mist 1%~8%, auxiliary agent 2%~20%.ThisInvention is using polytetrafluoroethylene (PTFE) (i.e. PTFE) resin, aviation kerosine, graphene micro mist and auxiliary agent as raw material, aviation kerosine and grapheneMicro mist plays synergistic effect in poly tetrafluoro ethylene matrix, improves the intensity, electric conductivity and thermal conductivity of product；Specifically, boatEmpty kerosene may penetrate between the particle of same component and the interface of different component, generates lubricant effect, make graphene micro mist andAuxiliary agent forms more uniform dispersity, after graphene micro mist and auxiliary agent are uniformly dispersed in polyflon matrix,Adjacent particle can play skeleton function, and provide channel with heat transfer for electronics circulation, so that the strength of materials be made to be promoted, and mentionThe electric conductivity and thermal conductivity of high material.Provided by the invention preparation method is simple, passes through stewing process and each compression processSuccessive cooperation, realize the gradually densification of material, make Material reinforcement, and make to form stable gantry between particle, rise enhancing makeWith, and channel is provided with heat transfer for electronics circulation, improve the electric conductivity and thermal conductivity of material.
Test result shows that the tensile strength of modified teflon material provided by the invention reaches 30MPa or more, leadsElectrostrictive coefficient reaches 500S/cm or more, and thermal coefficient reaches 0.48W/ (mK) or more, shows excellent strength character, conductionProperty and thermal conductivity.
Specific embodiment
The present invention provides a kind of modified teflon materials, are made by the raw material comprising following quality than component:
The present invention is using polytetrafluoroethylene (PTFE) (i.e. PTFE) resin, aviation kerosine, graphene micro mist and auxiliary agent as raw material, aviation coalOil plays synergistic effect with graphene micro mist in poly tetrafluoro ethylene matrix, improves the intensity, electric conductivity and thermal conductivity of product；Specifically, aviation kerosine may penetrate between the particle of same component and the interface of different component, lubricant effect is generated, graphite is madeAlkene micro mist and auxiliary agent form more uniform dispersity, and graphene micro mist and auxiliary agent disperse in polyflon matrixAfter uniformly, adjacent particle can play skeleton function, and provide channel with heat transfer for electronics circulation, so that the strength of materials be made to mentionIt rises, and improves the electric conductivity and thermal conductivity of material.
In the present invention, the raw material for forming modified teflon material includes polyflon.The polytetrafluoroethyl-neOlefine resin is basis material, and content is 70%~90%, preferably 75%~82%.In the present invention, the polytetrafluoroethylene (PTFE)Number-average molecular weight be preferably 4,000,000~6,000,000.The present invention is not particularly limited the source of the polyflon,For general commercially available product.
In the present invention, the raw material for forming modified teflon material further includes aviation kerosine.The aviation kerosine is preferredAviation kerosine for flash-point at 38~60 DEG C；If flash-point is lower than 38 DEG C, easily leads to polyflon and be unable to get abundant profitIt is sliding, during following process, the defects of causing material to generate micro-crack, so that the performances such as the intensity of material are significantly reduced, ifFlash-point is higher than 60 DEG C, then its permeability declines, and cannot be efficiently entering the interface of component particles, it is difficult to make graphene micro mist and helpAgent is dispersed in matrix, it is difficult to formed and stablize gantry and electronics heat transmission channel, can equally reduce material intensity andElectrical and thermal conductivity performance.In some embodiments of the invention, the aviation kerosine includes D40 aviation kerosine and/or D60 aviation coalOil.The present invention is not particularly limited the source of the aviation kerosine, is general commercially available product.
In the present invention, the content of the aviation kerosine is 5%~20%, if content is lower than 5%, it is former to be unable to fully infiltrationExpect particle, good lubricant effect cannot be played, easily lead to that cracking occurs in product and dimensional discrepancy increases, if content is higher than20%, then graphene micro mist, auxiliary agent and resin matrix cannot be made to form intimate-association state, easily reduction product strength, whileIntergranular resistance is obviously reduced, and has stronger locomitivity, so that product edge is generated waveform, causes product structure unstable.In the present invention, the content of the aviation kerosine is preferably 14%~18%, and under the dosage, it is strong can further to promote productDegree, electric conductivity and thermal conductivity.
In the present invention, the raw material for forming modified teflon material further includes graphene micro mist.The graphene micro mistGraphene sheet layer form portal structure in the resin that aviation kerosine infiltrates, to resin matrix generate humidification, and for electricitySubflow is logical to provide channel with heat transfer, improves electric conductivity and thermal conductivity.In the present invention, in the graphene micro mist, grapheneThe thickness of lamella preferably≤2nm if lamellar spacing is excessive can not generate shape in conjunction with good surface between other componentsState influences properties of product；It is furthermore preferred that graphene sheet layer is with a thickness of 1~2nm.In the present invention, in the graphene micro mist, stoneThe mean outside diameter of black alkene lamella is preferably 0.5~10 μm, if outer diameter is too small, is not easy to be connected with periphery lamella, be formed stableBridging structure, if outer diameter is excessive, it will cause lamella overlappings, cannot give full play to graphene sheet layer in PTFE resin matrixHumidification.The present invention is not particularly limited the source of the graphene micro mist, for general commercially available product or according to this field skillPreparation method known to art personnel obtains.
In the present invention, the content of graphene micro mist is 1%~8%, if content is lower than 1%, lamella grain spacing is excessive,Portal structure can not be formed, can not achieve the enhancing to whole resin matrix, if content is higher than 8%, is easy to appear micro mist aggregation,The structure of PTFE resin matrix can be destroyed, mechanical strength of resin is reduced.In the present invention, the content of the graphene micro mist is preferably 1%~5%, under the dosage, it can further promote product strength, electric conductivity and thermal conductivity.
In the present invention, the raw material for forming modified teflon material further includes auxiliary agent, and the content of the auxiliary agent is 2%~20%, preferably 2%~10%.In the present invention, the auxiliary agent is preferably toughener, anti-wear agent, extrusion aid, antistatic agent and profitOne or more of lubrication prescription can select above-mentioned auxiliary agent according to the special functional demands of processing and different field.Of the inventionIn one embodiment, the auxiliary agent is toughener, anti-wear agent and extrusion aid；In another embodiment of the present invention, described to helpAgent is toughener, antistatic agent and lubricant；In another embodiment of the present invention, the auxiliary agent be anti-wear agent, extrusion aid,Antistatic agent and lubricant.Specific type of the present invention to the toughener, anti-wear agent, extrusion aid, antistatic agent and lubricantIt is not particularly limited, is various substances well known to those skilled in the art.
Wherein, the toughener is preferably in polyethyl acrylate, butyl polyacrylate and polymethyl methacrylateIt is one or more of.The content of the toughener in the feed is preferably 0%~6%.It is described when selecting toughener in the auxiliary agentThe content of toughener is preferably 1%~6%.
Wherein, the anti-wear agent is preferably one or more of carborundum powder, alumina powder and silicon dioxide powder.It is describedThe content of anti-wear agent in the feed is preferably 0%~10%.When selecting anti-wear agent in the auxiliary agent, the content of the anti-wear agent is excellentIt is selected as 5%~10%.
Wherein, the extrusion aid is preferably one or more of toluene and dimethylbenzene.The extrusion aid is in the feedContent is preferably 0%~20%.When selecting extrusion aid in the auxiliary agent, the content of the extrusion aid is preferably 5%~20%.
Wherein, the antistatic agent is preferably one or more of copper powder, silver powder and carbon black.The antistatic agent is in originalContent in material is preferably 0%~8%.When selecting antistatic agent in the auxiliary agent, the content of the antistatic agent is preferably 1%~8%.
Wherein, the lubricant is preferably one or more of graphite and molybdenum disulfide.The lubricant is in the feedContent be preferably 0%~20%.When selecting lubricant in the auxiliary agent, the content of the lubricant is preferably 5%~20%.
The present invention provides a kind of modified teflon materials, are made by the raw material comprising following quality than component: poly-Tetrafluoroethylene resin 70%~90%, aviation kerosine 5%~20%, graphene micro mist 1%~8%, auxiliary agent 2%~20%.ItsIn, aviation kerosine and graphene micro mist play synergistic effect in poly tetrafluoro ethylene matrix, improve the performances such as the intensity of product；Specifically, aviation kerosine may penetrate between the particle of same component and the interface of different component, lubricant effect is generated, graphite is madeAlkene micro mist and auxiliary agent form more uniform dispersity, and graphene micro mist and auxiliary agent disperse in polyflon matrixAfter uniformly, adjacent particle can play skeleton function, so that the strength of materials be made to be promoted, while also mention for electronics circulation with heat transferFor channel, the electric conductivity and thermal conductivity of material are improved.
The present invention also provides a kind of preparation method of modified teflon material as described in the above technical scheme, packetsInclude following steps:
A) it by the mixing of polyflon, aviation kerosine, graphene micro mist and auxiliary agent and stewing process, is mixedMaterial；
B) high temperature compacting is carried out to the mixture, obtains compacting product；
Temperature >=145 DEG C of the high temperature compacting；
C) low temperature compacting and dry oil removing are carried out to the compacting product, obtains modified teflon material；
Temperature≤50 DEG C of the low temperature compacting.
Wherein, type, dosage and the source etc. of the polyflon, aviation kerosine, graphene micro mist and auxiliary agentWith it is consistent described in above scheme, this is no longer going to repeat them.
It, first will be at the mixing of polyflon, aviation kerosine, graphene micro mist and auxiliary agent and standing according to the present inventionReason, obtains mixture.
The present invention is not particularly limited the mixed mode, according to mixing method well known to those skilled in the art,Each component can be mixed, can such as be mixed by stirring.The present invention is not particularly limited the sequence of mixing, will be eachComponent mixes well.
In the present invention, after each component is mixed, stewing process is carried out, spreads kerosene sufficiently between each component, sufficiently soakedMoisten the interface of particle and different component, the material system for providing a dispersity for following process and being well combined.The present inventionIn, the stewing process is preferably constant temperature stewing process.The temperature of the constant temperature stewing process is preferably 20~50 DEG C, more preferablyIt is 30~45 DEG C, most preferably 23~27 DEG C.The time of the constant temperature stewing process is preferably 12~24 hours.In above-mentioned standingAfter processing, mixture is obtained.
According to the present invention, after obtaining mixture, high temperature compacting is carried out to the mixture, obtains compacting product.
Wherein, temperature >=145 DEG C of the high temperature compacting, in a most preferred embodiment, are by preferably 145~165 DEG C150~160 DEG C.The pressure of the high temperature compacting is preferably 3~4.5MPa, is 3.5~4.2MPa in a most preferred embodiment.
In the present invention, after obtaining mixture, it is preferably carried out pressing operation: b1) precompressed is carried out to the mixture,Obtain material base；B2 high temperature compacting) is carried out to the material base, obtains compacting product.
Wherein, the step b1) in, the precompressed is preferably constant temperature precompressed.The temperature of the constant temperature precompressed is preferably 35~40 DEG C, if temperature is too low, material viscosity is bigger than normal, it is difficult to be compacted each component, if temperature is excessively high, aviation kerosine is easily wavedHair, leads to Local Cracking.In the present invention, the pressure of the constant temperature precompressed is preferably 0.4~1.0MPa, difficult if hypotonyWith abundant compacting mixture material, if hypertonia, aviation kerosine loss is easily led to, subsequent operation is unfavorable for.In the present invention, instituteIt states precompressed and preferably includes pressure maintaining, the time of the pressure maintaining is preferably 50~80min.
Wherein, the step b2) in, temperature >=145 DEG C of the high temperature compacting, preferably 145~165 DEG C, optimalSelect is 150~160 DEG C in embodiment.The pressure of high temperature compacting is preferably 3~4.5MPa, in a most preferred embodiment for3.5~4.2MPa.By above-mentioned precompressed, reduce suitable aviation kerosine, and material forms more close institutional framework,Again by the extrusion under step b2) high temperature and pressure, the compacting product of stable structure can be obtained；If temperature and pressure are too small,It is difficult to complete extrusion process, if temperature and pressure are excessive, product size can be caused unstable.In the present invention, the high-temperature high-pressureSystem preferably pushes, and can carry out by the machine of pushing, material is pressed into strip material.After the compacting of above-mentioned high temperature, suppressedProduct.
According to the present invention, after obtaining compacting product, low temperature compacting and dry oil removing is carried out to the compacting product, are modifiedPolytetrafluoroethylene material.
In the present invention, before carrying out low temperature compacting, preferably also cooled down.In the present invention, the temperature of the cooling is preferredIt is 30~70 DEG C, more preferably 38~42 DEG C；The time of the cooling is preferably 30~35min.The present invention is reduced by coolingThe evaporation rate for squeezing out aviation kerosine in sample, guarantees the combination of storeroom, preferably cooperates subsequent compacting.
In the present invention, the temperature of the low temperature compacting is preferably≤50 DEG C, more preferably 35~50 DEG C, is most preferably being implementedIt is 40~45 DEG C in example.The pressure of the low temperature compacting is preferably 3~6MPa, is in a most preferred embodiment 4~5MPa.This hairIn bright, the low temperature compacting is preferably rolled, and material can be pressed into polytetrafluoroethylene (PTFE) base band by means of calender.The present inventionIn, the linear velocity of the compacting is preferably 0.8~1.0m/min.
In the present invention, the temperature of the dry oil removing is preferably 280~300 DEG C.The kerosene in material is removed by oil removing,The intergranular interface PTFE is eliminated, material is further enhanced.
In preparation process of the invention, by the successive cooperation of above-mentioned stewing process and each compression process, material is realizedIt gradually densifies, makes Material reinforcement, if reducing compacting number, more gap and density unevenness problem easily occur in product, leadProduct strength decline is caused, conductive and thermal conductivity is uneven.
Test result shows that the tensile strength of modified teflon material produced by the present invention reaches 30MPa or more, leadsElectrostrictive coefficient reaches 500S/cm or more, and thermal coefficient reaches 0.48W/ (mK) or more, shows excellent strength character, conductionProperty thermal conductivity.
Through the above-mentioned preparation process of the present invention, the polytetrafluoroethylene (PTFE) based belt material being had excellent performance, the material can be by notSame processing technology, is prepared into the various systems such as polytef flocks, polytetrafluoroethylfilament filament, microporous teflon membranProduct are applied to each field.
For a further understanding of the present invention, the preferred embodiment of the invention is described below with reference to embodiment, stillIt should be appreciated that these descriptions are only further explanation the features and advantages of the present invention, rather than to the claims in the present inventionLimitation.
Embodiment 1
Raw material: polyflon (trade mark F-104) 70%, aviation kerosine (38 DEG C of flash-point, trade mark Exxsol) 20%,Graphene micro mist (for graphene sheet layer with a thickness of 1nm, lamella mean outside diameter is 2 μm) 4%, toughener butyl polyacrylate 2% is resistance toGrinding agent copper powder 3%, extrusion aid toluene 8%.
Preparation:
S1: after mixing is sufficiently stirred in said components, constant temperature stands 12 hours at 25 DEG C, obtains mixture；
S2: gained mixture being placed in preformer and carries out precompressed and pressure maintaining, and precompressed is constant temperature precompressed, and temperature is 35 DEG C,Pressure is 0.7MPa, and pressure maintaining 50min obtains material base；
S3: gained material base being put into pressing device and is extruded into item by screw rod pushing machine, and press temperature is 150 DEG C, pressureFor 3.5MPa, compacting product are obtained；
S4: gained compacting product being put into warm water cooling, and water temperature is 40 DEG C, cooling time 30min；
S5: product after cooling is put into calender and is pressed into polytetrafluoroethylene (PTFE) base band, press temperature is 40 DEG C, and pressure is4MPa, compacting linear velocity are 0.8m/min；
S6: being put into dry degreasing unit for product after calendering, and temperature is 280 DEG C, after dry, obtains modified TeflonMaterial.
Embodiment 2
Raw material: polyflon (trade mark 213X) 80%, aviation kerosine (50 DEG C of flash-point, trade mark Exxsol) 15%,Graphene micro mist (for graphene sheet layer with a thickness of 1.7nm, lamella mean outside diameter is 5 μm) 3%, toughener polymethyl methacrylate5%, antistatic agent silver powder 6%, lubricant graphite 12%.
Preparation:
S1: after mixing is sufficiently stirred in said components, constant temperature stands 15 hours at 20 DEG C, obtains mixture；
S2: gained mixture being placed in preformer and carries out precompressed and pressure maintaining, and precompressed is constant temperature precompressed, and temperature is 35 DEG C,Pressure is 0.4MPa, and pressure maintaining 60min obtains material base；
S3: gained material base being put into pressing device and is extruded into item by screw rod pushing machine, and press temperature is 160 DEG C, pressureFor 4.2MPa, compacting product are obtained；
S4: gained compacting product being put into warm water cooling, and water temperature is 40 DEG C, cooling time 35min；
S5: product after cooling is put into calender and is pressed into polytetrafluoroethylene (PTFE) base band, press temperature is 45 DEG C, and pressure is5MPa, compacting linear velocity are 1.0m/min；
S6: being put into dry degreasing unit for product after calendering, and temperature is 290 DEG C, after dry, obtains modified TeflonMaterial.
Embodiment 3
Raw material: polyflon (trade mark 601X) 90%, aviation kerosine (60 DEG C of flash-point, trade mark Exxsol) 5%, stoneBlack alkene micro mist (for graphene sheet layer with a thickness of 2nm, lamella mean outside diameter is 10 μm) 2%, anti-wear agent silicon dioxide powder 10% helps crowdedAgent dimethylbenzene 16%, antistatic agent copper powder 5%, lubricant molybdenum disulfide 15%.
Preparation:
S1: after mixing is sufficiently stirred in said components, constant temperature stands 24 hours at 23 DEG C, obtains mixture；
S2: gained mixture being placed in preformer and carries out precompressed and pressure maintaining, and precompressed is constant temperature precompressed, and temperature is 38 DEG C,Pressure is 0.5MPa, and pressure maintaining 70min obtains material base；
S3: gained material base being put into pressing device and is extruded into item by screw rod pushing machine, and press temperature is 155 DEG C, pressureFor 3.8MPa, compacting product are obtained；
S4: gained compacting product being put into warm water cooling, and water temperature is 40 DEG C, cooling time 30min；
S5: product after cooling is put into calender and is pressed into polytetrafluoroethylene (PTFE) base band, press temperature is 42 DEG C, and pressure is4.5MPa, compacting linear velocity are 1.0m/min；
S6: being put into dry degreasing unit for product after calendering, and temperature is 300 DEG C, after dry, obtains modified TeflonMaterial.
Comparative example 1
It is carried out according to the preparation process of embodiment 1, unlike, graphene micro mist is not added.
Comparative example 2
It is carried out according to the preparation process of embodiment 2, unlike, do not add aviation kerosine.
Comparative example 3
It is carried out according to the preparation process of embodiment 3, unlike, the proportion of 3 kinds of major ingredients is as follows in raw material:
Polyflon 60%, aviation kerosine 25%, graphene micro mist 12%.
Embodiment 4
Performance detection is carried out to Examples 1 to 3 and comparative example 1~3, as a result referring to table 1.Wherein, the test of tensile strengthReferring to national standard GB/T 1040, the test of electrical conductivity is referring to GB/T 2439, and the test of thermal coefficient is referring to GB10295.
The performance test results of 1 Examples 1 to 3 of table and comparative example 1~3
| Tensile strength, MPa | Electrical conductivity, S/cm | Thermal coefficient, W/ (mK) |
| Embodiment 1 | 32 | 510 | 0.51 |
| Embodiment 2 | 39 | 830 | 0.64 |
| Embodiment 3 | 36 | 640 | 0.59 |
| Comparative example 1 | 23 | 0.005 | 0.24 |
| Comparative example 2 | 14 | 31 | 0.29 |
| Comparative example 3 | 28 | 190 | 0.43 |
By the test result of Examples 1 to 3 it is found that modified teflon material provided by the invention has high intensity,Meanwhile electrical conductivity with higher and thermal coefficient, it was demonstrated that gained modified teflon material has excellent mechanicalnessCan, electric conductivity and thermal conductivity.
By the test result of comparative example 1~2 it is found that when lacking aviation kerosine or graphene micro mist in raw material, productIntensity, electric conductivity and thermal conductivity are greatly reduced, it was demonstrated that, in raw material of the invention, aviation kerosine cooperates with work with graphene micro mistWith the mechanical performance and electrical and thermal conductivity of product could be improved.
By the test result of comparative example 3 it is found that in the raw material polyflon, aviation kerosine, graphene micro mistWhen proportion breaks restriction ratio of the present invention, intensity, electric conductivity and the thermal conductivity of product are greatly reduced, it was demonstrated that, original of the inventionIn material, each component could improve the mechanical performance and electrical and thermal conductivity of product under restriction ratio.
The above description of the embodiment is only used to help understand the method for the present invention and its core ideas.To these embodimentsA variety of modifications will be readily apparent to those skilled in the art, the general principles defined herein can be withWithout departing from the spirit or scope of the present invention, it realizes in other embodiments.Therefore, the present invention will not be limitedIn the embodiments shown herein, and it is to fit to widest model consistent with the principles and novel features disclosed in this articleIt encloses.