CN102558586B - Preparation method of polyethylene-vinyl acetate composite film - Google Patents
Preparation method of polyethylene-vinyl acetate composite film Download PDFInfo
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- CN102558586B CN102558586B CN201110417749.2A CN201110417749A CN102558586B CN 102558586 B CN102558586 B CN 102558586B CN 201110417749 A CN201110417749 A CN 201110417749A CN 102558586 B CN102558586 B CN 102558586B
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Abstract
The invention relates to a preparation method of a polyethylene-vinyl acetate composite film, belonging to the field of modification and preparation of high-conductivity materials. Conducting polymers and graphene are utilized to modify polyethylene-vinyl acetate (EVA), and an in-situ polymerization method is utilized to obtain the high-conductivity composite material. Compared with the existing modified high molecular material (including doping carbon nanotubes, carbon fibers and the like), the graphene-polyaniline codoped EVA material has the advantages of much higher conductivity and lower manufacturing cost.
Description
Technical field
The present invention relates to a kind of preparation method of polyethylene-vinyl acetate composite film, utilize conductive polymers and Graphene modified poly ethylene vinyl acetate (EVA), employing situ aggregation method obtains the matrix material of high conductivity, belongs to the modification preparation field of high conducting material.
Background technology
Compare with intrinsically conducting macromolecular material, the conductive polymeric composite being composited by conducting medium and macromolecular material because of polymer kind extensively, be easy to suitability for industrialized production, be easy to the advantages such as machine-shaping, be widely used in conduction, antistatic, planar heat producing body, anti-electromagnetic interference, the field such as explosion-proof.Current alternative conducting medium mainly contains metal system and charcoal system; At traditional charcoal, be in conducting medium, carbon black (CCB) and carbon fiber (CF) are most widely used, but these carbon element media generally need larger addition just can make macromolecular material reach desirable conductivity, therefore, when conducting mediums such as using carbon black and graphite carries out property modification to macromolecular material, tend to produce degradation problem under material mechanical performance, heat-resistant stability energy and processing characteristics.Since self-discovery carbon nanotube, carbon nanotube is also developed conductive polymers as main doping agent; The plastic of poly vinyl acetate (EVA) of doping 30% carbon black of reporting on CARBON for 2011, the EVA of 15% carbon fiber that adulterates, the EVA of 5% carbon nanotube that adulterates, its specific conductivity is respectively 2.5 * 10
-6s/cm, 5.0 * 10
-5s/cm, 2.5 * 10
-4s/cm.
After Graphene in 2004 is successfully prepared by " micromechanics is peeled off " method by geim seminar of Univ Manchester UK, become the most attracting study hotspot of material circle, region of chemistry and Condensed Matter Physics circle; Graphene relies on its excellent electroconductibility and extremely low add-on, become a kind of conductive modified agent that has potentiality, as Anjanapura etc. is undertaken compound by solution combined and situ aggregation method by the Graphene of thermal treatment gained and aqueous polyurethane, when the Graphene content adding is 3 wt%, the specific conductivity of aqueous polyurethane/graphene complex is 2.24 * 10
-4s/cm[A. V. Raghu, Y. R. Lee, H. M. Jeong, C. M. Shin, et al. Preparation and Physical Properties of Waterborne Polyurethane/Functionalized Graphene Sheet Nanocomposites. Macromol. Chem. Phys. 2008,209,2487-2493].
Electron propagation ducts pattern different from the past, as line-line connecting passage pattern: conductive doped polymkeric substance (as polyacetylene, polypyrrole, Polythiophene); Post--post connecting passage pattern: doped carbon nanometer pipe; Face--face connecting passage pattern: doped graphene; The object of the present invention is to provide a kind of mentality of designing of brand-new composite conductive polymer material, designed a kind of brand-new heterogeneous composite conducting material with line-face skeleton pattern expansion structure conductive network; Utilize Graphene and conducting polymer as doping agent, prepare composite conducting material.Such mixture, the microchannel form of its transmission electronic has: line-line, line-face, face-face, thus conductive channel quantity increases greatly, causes conductivity greatly to promote.And utilize this mentality of designing, and prepared the EVA material of Graphene and Polyaniline Doped, its specific conductivity has reached 0.1S/cm.
Summary of the invention
The present invention designs the novel conductive model that a kind of line-face-toe-in closes, with Graphene (GNS), polyaniline (PANI) is the matrix material that main doping agent increase conductive channel the method for utilizing in-situ polymerization successfully synthesize GNS/ PANI/ EVA high conductivity, can be widely used in cable shield material, antistatic material, area of solar cell etc., have huge application prospect.
The invention has the beneficial effects as follows:
With respect to existing modified polymer material (comprising doping vario-properties such as utilizing carbon nanotube, carbon fiber), the electroconductibility of the EVA material that Graphene and polyaniline are composite mixed improves a lot, and low cost of manufacture.
The present invention specifically implements by the following step:
The first step: prepare graphene oxide by chemical oxidation;
Second step: at high temperature thermal reduction of the graphene oxide of preparing is become to Graphene;
The 3rd step: select suitable solvent to adopt at low temperatures situ aggregation method to prepare the composite solution of Graphene and polyaniline, in the composite solution of Graphene and polyaniline, the mass ratio of Graphene and polyaniline is 1:2 ~ 1:4, and in the composite solution of Graphene and polyaniline, the mass percentage concentration of Graphene is controlled at 5% ~ 30%;
The 4th step: plastic of poly vinyl acetate is mixed with to solution, mixes with the composite solution of Graphene and polyaniline, stir, ultrasonic;
The 5th step: pour above-mentioned mixing solutions into mould, vacuum-drying, film forming.
The described method the first step, prepares graphite oxide by graphite oxidation intercalation, and these methods include but not limited to: hummer method, staudenmair method.
Described method second step, notes under protection of inert gas 700 ℃ ~ 1100 ℃ of characteristic temperature scopes.
Described method the 3rd step, employing be situ aggregation method, keep pH value to be not more than 3, polymerization temperature is less than 20 ℃; Described suitable solvent is N methyl-2-pyrrolidone.
The concrete preparation method of described method the 3rd step is: at 0 ~ 10 ℃, to three-necked bottle, adding mass percentage concentration is 1 ~ 2% Sodium dodecylbenzene sulfonate solution, drips aniline monomer, adds defoamer propyl carbinol, adds 2mg/ml
Graphene solution, add hydrochloric acid and regulate pH value to 1 ~ 3, stir, dripping mass percentage concentration is the ammonium persulphate of 5 ~ 15 %, reaction 4 ~ 8 h, filter, and use respectively acetone, distilled water wash is neutral to PH, vacuum-drying 24 ~ 48 h at 50 ~ 80 ℃, and dissolve with N-Methyl pyrrolidone; The add-on of defoamer and aniline monomer volume ratio are 300:1 ~ 500:1, Sodium dodecylbenzene sulfonate and aniline monomer mol ratio are 1.5:1 ~ 1.8:1, Graphene add-on and aniline monomer mass ratio are 1:2 ~ 1:4, and the add-on of ammonium persulphate and aniline monomer mol ratio are 2.5:1 ~ 3:1.
Described method the 4th step, plastic of poly vinyl acetate is dissolved with the mixed solvent of dimethylbenzene and N-Methyl pyrrolidone, the dimethylbenzene of every 60 ~ 90 ml and the mixed solvent of N-Methyl pyrrolidone dissolve 1.88 ~ 2.2 grams of plastic of poly vinyl acetate, in dimethylbenzene and N-Methyl pyrrolidone mixed solvent, the volume ratio of dimethylbenzene and N-Methyl pyrrolidone is 1:1 ~ 3:1, stir ultrasonic 2 ~ 5h with the composite solution of Graphene and polyaniline.
Described method the 5th step, temperature is controlled at 50 ~ 80 ℃, vacuum-drying 24 ~ 48 h.
Accompanying drawing explanation
Fig. 1 is the AFM figure of Graphene used in example one, example three, example four, and AFM figure display piece layer thickness is in 0.6 nm left and right, and interpret sample is single-layer graphene;
Fig. 2 is the optical photograph of composite conductive film in example four, has as can be seen from the figure prepared complete laminated film, its smooth surface, even;
Fig. 3 is the SEM figure of composite conductive film in example four, can find out that Graphene, polyaniline disperse at EVA relatively good from SEM figure, does not significantly reunite;
A in Fig. 4, b and c curve are respectively comparative examples 1, the AC conductivity of example three and example four composite membranes is with the change curve of frequency, sample in comparative example 2 sample test curves and example one is similar, as can be seen from the figure the laminated film specific conductivity in example one increases along with the increase of frequency, explanation does not form conductive network in laminated film, and laminated film specific conductivity in example three and example four is along with frequency is substantially constant, illustrate and in laminated film, formed conductive network, thereby illustrate that being mixed with altogether of Graphene and PANI is beneficial to formation conductive network, thereby also can build the conductive network with line-face skeleton pattern by side light Graphene/PANI/EVA matrix material.
Embodiment
Below in conjunction with example, further illustrate content of the present invention:
In the EVA adopting, vinyl acetate content is 14 %, and specific conductivity is 5 * 10
-15s/cm.
comparative example 1:
Graphene/EVA(mass ratio 2:98) preparation of laminated film
1, the preparation of graphite oxide: utilize improved staudenmair method, add natural flake graphite, HNO in 98% the vitriol oil
3and KClO
3, control 10 ℃ of reacting liquid temperatures, after stirring reaction 5 h, with deionized water, reaction solution dilution is refiltered, ionized water fully washs until neutral, then dry.
2, by graphene oxide under the condition of nitrogen protection, rise to 1000 ℃ of thermal reduction 30 s.
3,40 mg Graphenes are made into the solution of 2 mg/ml with 20 ml N-Methyl pyrrolidone; 1.98g EVA is joined to wiring solution-forming in 60 ml dimethylbenzene; Above-mentioned two kinds of solution are mixed, stir 2 h, ultrasonic 4 h.
4, pour ultrasonic uniform solution into mould at 50 ℃, vacuum-drying 48 h, the demoulding, recording specific conductivity is 3.26 * 10
-5s/cm.
comparative example 2:
PANI/EVA(mass ratio 5:95) preparation of laminated film
1, the preparation of polyaniline: 5
ounder C, to the three-necked bottle of 250ml, adding mass concentration is 1.25% Sodium dodecylbenzene sulfonate (DBSA), 60 ml, drip 0.002mol aniline monomer, add defoamer propyl carbinol 40ml, add hydrochloric acid and regulate pH value to 2, stir, dripping mass concentration is 15% ammonium persulphate (APS) 70ml reaction 9h, filter, use respectively acetone, distilled water wash is neutral to PH, 60
ovacuum-drying 24h under C.
2, take 0.1g PANI and with 10mlN-methyl-2-pyrrolidone, be made into the solution of 10mg/ml; 1.98g EVA is joined to wiring solution-forming in 60ml dimethylbenzene; These two kinds of solution are mixed, stir 2h, ultrasonic 4h.
3, pour ultrasonic uniform solution into mould at 75 ℃, vacuum-drying 30h, the demoulding, recording specific conductivity is 7.52 * 10
-5s/cm.
example three: Graphene/PANI/EVA laminated film (mass ratio is 2:5:93)
1, with the step 1 in example one.
2, with the step 2 in example one.
3, the preparation of the composite solution of Graphene and polyaniline:
5
ounder C, to the three-necked bottle of 250 ml, adding mass concentration is 1.25 % Sodium dodecylbenzene sulfonate (DBSA) 30 ml, drip 0.1 ml aniline monomer, add defoamer propyl carbinol 40ml, add 2 mg/ml graphene solution 20 ml, add hydrochloric acid and regulate pH value to 2, stir, dripping mass concentration is that 15% ammonium persulphate (APS), 40 ml react 9 h, filters, and uses respectively acetone, distilled water wash is neutral to PH, 60
ovacuum-drying 24 h under C, and dissolve with 100 ml N-Methyl pyrrolidone.
4, by dimethylbenzene and N-Methyl pyrrolidone mixed solvent wiring solution-forming for 1.88g EVA, the volume of dimethylbenzene and N-Methyl pyrrolidone mixed solvent is 60 ml, in dimethylbenzene and N-Methyl pyrrolidone mixed solvent, the volume ratio of dimethylbenzene and N-Methyl pyrrolidone is 2:1, mix with the Graphene of upper step and the composite solution of polyaniline, mechanical stirring 3 h, and ultrasonic 4 h.
5, pour ultrasonic uniform solution into mould at 75 ℃, vacuum-drying 30 h, the demoulding, recording specific conductivity is 7.52 * 10
-3s/cm.
example four: the preparation of Graphene/PANI/EVA laminated film (mass ratio is 4:8:88)
1, with the step 1 in example one
2, with the step 2 in example one
3, the preparation of the composite solution of Graphene and polyaniline: 0
ounder C, to the three-necked bottle of 250 ml, adding mass concentration is 1.25 % Sodium dodecylbenzene sulfonate (DBSA) 60 ml, drip 0.002 mol aniline monomer, add defoamer propyl carbinol 40 ml, add 2 mg/ml graphene solution 50 ml, add hydrochloric acid and regulate pH value to 2, stir, dripping mass concentration is that 15 % ammonium persulphate (APS) 70 ml react 9 h, filters, and uses respectively acetone, distilled water wash is neutral to PH, 60
ovacuum-drying 24 h under C, and dissolve with 75 ml N-Methyl pyrrolidone.
4, by dimethylbenzene and N-Methyl pyrrolidone mixed solvent wiring solution-forming for 2.2g EVA, the volume of dimethylbenzene and N-Methyl pyrrolidone mixed solvent is 90 ml, in dimethylbenzene and N-Methyl pyrrolidone mixed solvent, the volume ratio of dimethylbenzene and N-Methyl pyrrolidone is 3:1, mix with the 3rd Graphene of step and the composite solution of polyaniline, mechanical stirring 3h, and ultrasonic 2 h, the content of Graphene in the matrix material of preparation: polyaniline: EVA is respectively 4wt%:8wt%: 88wt%.
5, pour the composite solution mixing into mould at 50 ℃, vacuum-drying 48 h, the demoulding, prepared composite conducting membrane conductivity is 1.07 * 10
-1s/cm.
Claims (5)
1. a preparation method for polyethylene-vinyl acetate composite film, comprises the steps:
(1) by chemical oxidation, prepare graphene oxide;
(2) at high temperature thermal reduction of the graphene oxide of preparing is become to Graphene;
(3) select suitable solvent to adopt at low temperatures situ aggregation method to prepare the composite solution of Graphene and polyaniline, in the composite solution of Graphene and polyaniline, the mass ratio of Graphene and polyaniline is 1:2 ~ 1:4, and in the composite solution of Graphene and polyaniline, the mass percentage concentration of Graphene is controlled at 5% ~ 30%;
(4) plastic of poly vinyl acetate is mixed with to solution, mixes with the composite solution of Graphene and polyaniline, stir, ultrasonic;
(5) pour above-mentioned mixing solutions into mould, vacuum-drying, film forming;
The concrete preparation method of described step 3 is: at 0 ~ 10 ℃, to three-necked bottle, adding mass percentage concentration is 1 ~ 2% Sodium dodecylbenzene sulfonate solution, drip aniline monomer, add defoamer propyl carbinol, the graphene solution that adds 2mg/ml, add salt acid for adjusting pH value to 1 ~ 3, stir, dripping mass percentage concentration is the ammonium persulphate of 5 ~ 15 %, reaction 4 ~ 8 h, suction filtration, uses respectively acetone, and distilled water wash is neutral to pH, vacuum-drying 24 ~ 48 h at 50 ~ 80 ℃, and dissolve with N-Methyl pyrrolidone; The add-on of defoamer and aniline monomer volume ratio are 300:1 ~ 500:1, Sodium dodecylbenzene sulfonate and aniline monomer mol ratio are 1.5:1 ~ 1.8:1, Graphene add-on and aniline monomer mass ratio are 1:2 ~ 1:4, and the add-on of ammonium persulphate and aniline monomer mol ratio are 2.5:1 ~ 3:1;
The concrete preparation method of described step 4 is: plastic of poly vinyl acetate is dissolved with the mixed solvent of dimethylbenzene and N-Methyl pyrrolidone, the dimethylbenzene of every 60 ~ 90 ml and the mixed solvent of N-Methyl pyrrolidone dissolve 1.88 ~ 2.2 grams of plastic of poly vinyl acetate, in dimethylbenzene and N-Methyl pyrrolidone mixed solvent, the volume ratio of dimethylbenzene and N-Methyl pyrrolidone is 1:1 ~ 3:1, stir ultrasonic 2 ~ 5h with the composite solution of Graphene and polyaniline.
2. the preparation method of a kind of polyethylene-vinyl acetate composite film as claimed in claim 1, is characterized in that: in described step 1, the method for graphite oxidation intercalation being prepared to graphite oxide includes but not limited to: hummer method, staudenmair method.
3. the preparation method of a kind of polyethylene-vinyl acetate composite film as claimed in claim 1, is characterized in that: described step 2 should be carried out under protection of inert gas, 700 ℃ ~ 1100 ℃ of temperature ranges.
4. the preparation method of a kind of polyethylene-vinyl acetate composite film as claimed in claim 1, is characterized in that: what described step 3 adopted is situ aggregation method, keeps pH value to be not more than 3, and polymerization temperature is less than 20 ℃; Described suitable solvent is N-Methyl pyrrolidone.
5. the preparation method of a kind of polyethylene-vinyl acetate composite film as claimed in claim 1, is characterized in that: described step 5 temperature is controlled at 50 ~ 80 ℃ vacuum-drying 24 ~ 48 h.
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| CN104448303B (en) * | 2014-11-20 | 2016-09-21 | 河南城建学院 | A kind of ethylene-vinyl acetate copolymer/polyaniline composite conducting material and preparation method thereof |
| CN105131408A (en) * | 2015-06-26 | 2015-12-09 | 中国航空工业集团公司北京航空材料研究院 | Graphene semiconductor shield material |
| CN105461948A (en) * | 2015-11-23 | 2016-04-06 | 南京航空航天大学 | Preparation method of conductive macromolecule non-covalent functionalized graphene modified electrokinetic energy conversion polymer material |
| CN107011568B (en) * | 2017-04-19 | 2019-12-20 | 上海电气集团股份有限公司 | Semiconductor polymer with composite graphene/carbon black as conductive medium and preparation method thereof |
| CN108878796A (en) * | 2017-05-16 | 2018-11-23 | 天津大学 | Graphene modified conductive polymer gel and its preparation method and application |
| CN109370226A (en) * | 2018-10-24 | 2019-02-22 | 嘉兴市海德姆智能电气有限公司 | A kind of preparation method of electromagnetic shielding material |
| CN109627562B (en) * | 2018-12-20 | 2020-05-26 | 中山大学 | Preparation method and application of conductive composite material |
| CN113265090A (en) * | 2021-05-14 | 2021-08-17 | 东北大学 | Preparation method for coating polyaniline-doped graphene surface |
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| EP2036941A1 (en) * | 2007-09-13 | 2009-03-18 | Stichting Dutch Polymer Institute | Process for the preparation of a conductive polymer composition |
| CN101798462A (en) * | 2010-03-26 | 2010-08-11 | 武汉工程大学 | Graphene/conductive polymer composite film and preparation method thereof |
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| EP2036941A1 (en) * | 2007-09-13 | 2009-03-18 | Stichting Dutch Polymer Institute | Process for the preparation of a conductive polymer composition |
| CN101798462A (en) * | 2010-03-26 | 2010-08-11 | 武汉工程大学 | Graphene/conductive polymer composite film and preparation method thereof |
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