CN103613722A - Method for preparing magnetic halloysite molecularly imprinted polymer with specific adsorption to 2,4-dichlorophenoxyacetic acid - Google Patents

Method for preparing magnetic halloysite molecularly imprinted polymer with specific adsorption to 2,4-dichlorophenoxyacetic acid Download PDF

Info

Publication number
CN103613722A
CN103613722A CN201310624108.3A CN201310624108A CN103613722A CN 103613722 A CN103613722 A CN 103613722A CN 201310624108 A CN201310624108 A CN 201310624108A CN 103613722 A CN103613722 A CN 103613722A
Authority
CN
China
Prior art keywords
magnetic
halloysite nanotubes
halloysite
acid
polymerization
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN201310624108.3A
Other languages
Chinese (zh)
Other versions
CN103613722B (en
Inventor
钟世安
周成赟
张小娜
孔艳月
周玲
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Central South University
Original Assignee
Central South University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Central South University filed Critical Central South University
Priority to CN201310624108.3A priority Critical patent/CN103613722B/en
Publication of CN103613722A publication Critical patent/CN103613722A/en
Application granted granted Critical
Publication of CN103613722B publication Critical patent/CN103613722B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Landscapes

  • Solid-Sorbent Or Filter-Aiding Compositions (AREA)

Abstract

The invention discloses a method for preparing a magnetic halloysite molecularly imprinted polymer with specific adsorption to 2,4-dichlorophenoxyacetic acid. The preparation method comprises the following steps: preparing magnetic halloysite nano-tubes by using corroded halloysite nano-tubes by a coprecipitation method; reacting the magnetic halloysite nano-tubes and methacrylate in methylbenzene to obtain magnetic halloysite nano-tubes with double-bond-modified surfaces; after polymerizing the magnetic halloysite nano-tubes with double-bond-modified surfaces, the polymerized monomers and a crosslinker by taking the 2,4-dichlorophenoxyacetic acid as a template, then removing the 2,4-dichlorophenoxyacetic acid to obtain the magnetic halloysite molecularly imprinted polymer with specific adsorption to the 2,4-dichlorophenoxyacetic acid. The raw materials used in the preparation method are low in cost; the preparation method is easy to operate and easy to implement; the prepared magnetic halloysite molecularly imprinted polymer is stable in structure, has specific adsorption to the 2,4-dichlorophenoxyacetic acid, and can effectively separate and remove the 2,4-dichlorophenoxyacetic acid from a complex system.

Description

Preparation has the method for the magnetic halloysite molecularly imprinted polymer of specific adsorption to 2,4 dichlorophenoxyacetic acid
Technical field
The present invention relates to a kind of method 2,4 dichlorophenoxyacetic acid to the magnetic halloysite molecularly imprinted polymer of specific adsorption, function of dominant technical field of material prepared.
Background technology
Halloysite, a kind of aluminium silicon compound, chemical structure is similar to kaolin, i.e. Al 2si 2o 5(OH) 4nH 2o, but have again a little difference on pattern, halloysite has the tubular structure of hollow, and its structural unit is that water by unimolecular layer separates.The water of internal layer can cause physicochemical character to comprise organic interlayer and ion-exchange capacity.In addition, halloysite has two kinds of sizes, 10A and 7A, and wherein that moisture is 10A, water electrode is transformed into 7A after easily losing.Because the tubular structure that it is special, excellent performance, rich in natural resources and extremely low cost, halloysite all has very large potentiality and in recent years, has also won very large concern in a lot of fields.It is different from other unique tubular structure of aluminium silicon compound and good biocompatibility and very low toxicity makes it become a kind of very promising medicine supporting body.Halloysite is compared with carbon nanotube, and it is a kind of very economic starting material, can directly from clay raw ore, extract.The structure of halloysite is different from carbon nanotube and is, the latter is bar-shaped, and the former is the netted bar structure intermeshing, and this can be dissolved in solution or in polymeric web halloysite.Exactly because halloysite has so many excellent performance, for example, there are larger specific surface area, large aperture and abundant hydroxyl.
Molecular imprinting (MIT) is first template molecule and selected function monomer to be interacted and form mixture in suitable solvent, under linking agent effect, form again high cross-linked polymer, finally by specific means, remove after template molecule, in the molecularly imprinted polymer of acquisition (MIPs), leave binding site template molecule to specific recognition.MIPs, owing to having precordainment, identity and the large feature of practicality three, is widely used in many research fields such as chromatographic separation, Solid-Phase Extraction, mimetic enzyme catalysis, natural antibody simulation and membrane separation technique.The combination of magnetic-particle and molecularly imprinted polymer can be provided to the instrument of simple, quick a, high efficiency separation, like this can be so that original complicated filtering separation or centrifugation become simply, also actual being applied in separation.
At present, the preparation method of molecular imprinting is quite ripe, but it is rare to take the method that magnetic halloysite nanotubes prepares molecular imprinted polymer on surface as carrier.Although existing, utilize simple solvent thermal reaction to prepare halloysite Magnetic nano-pipe, it is only to load on halloysite surface, and the Z 250 particle unstable ferric oxide that easily changes into very makes part particle lose magnetism or occur leakage field.Conventional is surperficial at halloysite nanotubes by Fe 3 O 4 magnetic particle load, can be by the silicon-dioxide (SiO on halloysite nanotubes surface 2) cover, so direct modification that affects methacrylic acid, and affect synthesizing and adsorption selectivity energy of molecularly imprinted polymer.
2,4 dichlorophenoxyacetic acid (2,4-D) as plant growth inhibitor or agricultural chemicals, in world's agricultural planting technique, have a wide range of applications.2,4-D has been used a lot of years, although it is very poisonous for a lot of biologies.2,4 dichlorophenoxyacetic acid has non-volatile and solubility, and is difficult to biological degradation and directly photodissociation.Due to 2,4 dichlorophenoxyacetic acid can be in stratum infiltration migration, existing detection in underground water and surface water.2,4 dichlorophenoxyacetic acid is proved to be environment incretion interferent, and its chloride metabolic intermediate is accumulation in vivo easily, is typical three to cause pollutent.So specificity is selected very important of 2,4 dichlorophenoxyacetic acid.
Summary of the invention
The present invention is directed in prior art in traditional environment system 2,4-dichlorphenoxyacetic acid (2, the defect such as removal method 4-D) is time-consuming, effort, and removal efficiency is low, object is to be to provide a kind of Stability Analysis of Structures, 2,4-D is had to specific adsorption, and effectively 2 in complex system removed in separation, the preparation method of the magnetic halloysite molecularly imprinted polymer of 4-D, this preparation method's raw material is cheap, simple to operate, easy to implement.
The invention provides preparation to 2,4-D has the method for the magnetic halloysite molecularly imprinted polymer of specific adsorption, this preparation method obtains corroding halloysite nanotubes with sulfuric acid by halloysite nanotubes corrosion, described corrosion halloysite nanotubes and trivalent iron salt and divalent iron salt make magnetic halloysite nanotubes by coprecipitation method, described magnetic halloysite nanotubes and methacrylic acid react in toluene, obtain the magnetic halloysite nanotubes of the two keys of finishing; The magnetic halloysite nanotubes of the two keys of described finishing and polymerization single polymerization monomer and linking agent be take 2,4 dichlorophenoxyacetic acid after template is carried out polymerization, remove 2,4 dichlorophenoxyacetic acid, obtain;
Described 2,4-dichlorphenoxyacetic acid, polymerization single polymerization monomer, linking agent three's mol ratio is 1:2~6:16~24, wherein, polymerization single polymerization monomer is one or more in 4-vinylpridine, 2-vinyl pyridine, vinyl benzyl chloride, and linking agent is Vinylstyrene or ethylene glycol dimethacrylate;
The two magnetic halloysite nanotubes of key of described finishing and the mass ratio of polymerization single polymerization monomer are 1:1~2;
The proportionlity of described magnetic halloysite nanotubes, toluene, methacrylic acid three usage quantity is 1g:25~35mL:3~8mL.
The sulphuric acid soln that described corrosion halloysite nanotubes is is 0.5~2mol/L by concentration, under 55~65 ℃ of conditions, by halloysite nanotubes corrosion 12~15h, prepares.
Described polymerization is first by polymerization single polymerization monomer and 2,4-dichlorphenoxyacetic acid carries out self-assembly 6~12h at 0~5 ℃, obtain assembling liquid, in described assembling liquid, add magnetic halloysite nanotubes and the linking agent of the two keys of finishing first at 45~52 ℃ of pre-polymerization 3~7h, again at 53~65 ℃ of polymerization 18~22h, then at 75~85 ℃ of further polyase 13~7h.
Described polymerization adds a small amount of azo-bis-isobutyl cyanide or azo two cyanogen in different heptan as initiator.
Described reaction is to stir 18~24h at 65~70 ℃.
The described 2,4 dichlorophenoxyacetic acid that removes is to adopt methyl alcohol and the acetic acid mixed solvent that volume ratio is 8~9:1~2 to extract 1~2d.
Described method, corrosion halloysite nanotubes, trivalent iron salt and divalent iron salt three's reaction mass ratio is 0.2~0.5:0.6~0.9:0.50; Described trivalent iron salt is a kind of in Anhydrous Ferric Chloride, Iron(III) chloride hexahydrate, ferric sulfate; Described divalent iron salt is a kind of in four ferrous sulfate hydrates, Iron dichloride tetrahydrate, ferrous sulfate.
Described coprecipitation method reaction conditions: first, at 50~60 ℃, react after 0.5~1h, regulating pH is 9~11, then at 80~90 ℃, aging 4~5h.
The preparation method that 2,4-D is had to the magnetic halloysite molecularly imprinted polymer of specific adsorption of the present invention, comprises following concrete steps:
(1) coprecipitation method is prepared magnetic halloysite nanotubes (HNTS-Fe 3o 4):
Halloysite nanotubes is dispersed in the dilution heat of sulfuric acid that concentration is 0.5~2mol/L, after ultrasonic dispersion, in 55~65 ℃ of water-baths, stirring reaction 12~15h, filters, extremely neutral to pH with a large amount of distilled water washs, 40~60 ℃ of vacuum-dryings, obtain corroding halloysite nanotubes (HNTS);
Gained is corroded to halloysite nanotubes, trivalent iron salt and divalent iron salt iron to be dissolved in deionized water according to mass ratio 0.2~0.5:0.6~0.9:0.5, add a small amount of (take mixture total mass suitably add for benchmark) dispersion agent, ultrasonic dispersion, after under nitrogen protection, magnetic agitation 0.5~1h in 50~60 ℃ of water-baths; 6~12mL strong aqua is added dropwise to said mixture, control time for adding is 20~30min, the pH value of rear regulator solution is 9~11, rising temperature to 80~90 ℃, keep the aging 4~5h of temperature, finish reaction, thing to be mixed carries out after magnetic separation separation with magnet after being chilled to room temperature, with deionized water and dehydrated alcohol, respectively wash 3 times, vacuum-drying at 50~70 ℃, obtains HNTS-Fe 3o 4nanotube;
(2) prepare the magnetic halloysite nanotubes (MH-C=C) of the two keys of finishing:
Ratio in magnetic halloysite nanotubes, toluene, methacrylic acid three raw material usage quantity is that 1g:25~35mL:3~8mL adds, first be scattered in toluene magnetic halloysite nanotubes is ultrasonic, slowly drip methacrylic acid again, dropwise, 18~24h refluxes at 65~70 ℃; Reaction finishes with magnet, to carry out magnetic separation separation afterwards, uses successively toluene and absolute ethanol washing, and dry, obtains the magnetic halloysite nanotubes of the two keys of finishing;
(3) prepare magnetic halloysite molecularly imprinted polymer (MH-MIP):
By template molecule 2,4-D and polymerization single polymerization monomer in molar ratio 1:2~6 join in acetonitrile solution, pre-assembled 3~5h at 0~5 ℃; By the ratio of mol ratio 1:16~24 of 2,4-D:DVB, add DVB and a small amount of AIBN,
The magnetic halloysite nanotubes (mass ratio of its quality and polymerization single polymerization monomer is 1:1~2) that adds subsequently the two keys of finishing that make in step (2), ultrasonic dispersion, logical nitrogen half an hour, first at 45~52 ℃ of pre-polymerization 3~7h, again at 53~65 ℃ of polymerization 18~22h, then at 75~85 ℃ of further polyase 13~7h; After reaction finishes, products therefrom is carried out under externally-applied magnetic field to separation, after use acetone, alcohol and water repetitive scrubbing product, the final mixed solution with methyl alcohol/acetic acid (8~9:1~2, V:V) Soxhlet is extracted 1~2d, removes template molecule, vacuum-drying under room temperature, obtains magnetic halloysite molecularly imprinted polymer material.
Beneficial effect of the present invention: the present invention carrys out supported magnetic ferroferric oxide particle by the corrosion halloysite nanotubes making through sulfuric acid corrosion halloysite nanotubes first, and further at the two keys of finishing and adopt surface imprinted technology with 2,4-D is that template is synthetic to 2,4-D has specific adsorption, and effectively separation is removed 2 in complex system, the magnetic halloysite molecularly imprinted polymer of 4-D.The present invention adopts dilute sulphuric acid by halloysite nanotubes inner wall corrosion to a certain extent, enriched the aperture of halloysite nanotubes inwall, then utilizing coprecipitation method is that magnetic ferroferric oxide between 20~30nm is embedded in halloysite inwall by the yardstick of generation, greatly increased the stability of magnetic halloysite nanotubes material structure, in the life-span of reusing that is conducive to magnetic halloysite molecularly imprinted polymer, also reduced because Fe 3 O 4 magnetic particle load is at the surperficial modification rate that affects methacrylic acid of halloysite nanotubes simultaneously; Secondly, the present invention has selected suitable polymerization single polymerization monomer and linking agent, with the magnetic halloysite nanotubes with certain two key amount modification of surfaces, with 2,4-D for template molecule, the magnetic halloysite molecularly imprinted polymer that polymerization obtains is to 2,4-D has special structure matching and stronger Intermolecular Forces, fast specific recognition and in conjunction with 2,4-D, improved the selective adsorption efficiency to 2,4-D.The magnetic halloysite molecularly imprinted polymer structure making by the inventive method is stable especially, and reusability is good, good to the specific recognition of 2,4-D, can well use magnetic and carry out efficient selective separation; And its preparation method is simple, raw material is cheap and easy to get, technique is simple, easy to implement.
Accompanying drawing explanation
[Fig. 1] is corrosion halloysite nanotubes and the two magnetic halloysite nanotubes of key of finishing and the infrared spectra comparison diagram of magnetic halloysite molecularly imprinted polymer of embodiment 1 preparation.
[Fig. 2] is that the corrosion magnetic halloysite nanotubes of embodiment 1 preparation contrasts figure with the transmission electron microscope of magnetic halloysite molecularly imprinted polymer: left figure is corrosion magnetic halloysite nanotubes; Right figure is magnetic halloysite molecularly imprinted polymer.
[Fig. 3] is the X-ray diffraction comparison diagram of the corrosion magnetic halloysite nanotubes of pure magnetic ferroferric oxide nano-particles and embodiment 1 preparation: a is magnetic ferroferric oxide; B is corrosion magnetic halloysite nanotubes.
The non-molecularly imprinted polymer of magnetic halloysite that [Fig. 4] makes for embodiment 1 and the dynamic adsorption curve comparison figure of magnetic halloysite molecularly imprinted polymer.
The non-molecularly imprinted polymer of magnetic halloysite that [Fig. 5] makes for embodiment 1 and the adsorption isothermal line comparison diagram of magnetic halloysite molecularly imprinted polymer.
The non-molecularly imprinted polymer of magnetic halloysite that [Fig. 6] makes for embodiment 1 and the specific selectivity comparison diagram of magnetic halloysite molecularly imprinted polymer.
Embodiment
Following examples are to further illustrate of the present invention, rather than restriction protection domain of the present invention.
(1) kinetics absorption is investigated: by 2,4-D molecularly imprinted polymer joins 2 of concentration known, in 4-D sample solution, then be transferred on vibrator, and be oscillatory reaction 70min under 200rmp~300rmp at vibration rotating speed, interval sampling, the rear magnet that utilizes carries out magnetic resolution, get solution testing absorbancy and calculate the concentration after adsorption equilibrium, according to the concentration difference of front and back, obtain adsorptive capacity Q.
(2) equilibrium adsorption is investigated: magnetic halloysite molecularly imprinted polymer material (MH-MIP) and the non-molecularly imprinted polymer of magnetic halloysite (MH-NIP) (are made according to the preparation method of MH-MIP, just do not add 2,4-D template molecule) join respectively the series 2 of concentration known, in 4-D sample solution, in constant temperature oscillator, shake 24h, after utilize magnet to carry out magnetic separation separation, get supernatant liquid, test absorbancy calculates the concentration after adsorption equilibrium, according to the concentration difference of front and back, obtains adsorptive capacity Q.
(3) specific selectivity is investigated: the MH-MIP of equivalent is joined respectively to 2 of same concentrations, in 4-D and analog phenoxy acetic acid thereof and 4-methyl-2-chlorophenoxyacetic acid, in constant temperature oscillator, shake 24h, after utilize magnet to carry out magnetic resolution, get supernatant liquid, test respectively absorbancy and calculate the concentration after adsorption equilibrium, according to the concentration difference of front and back, obtain adsorptive capacity Q; The specific selectivity experiment of MH-NIP is identical with above-mentioned steps.
Embodiment 1
(1) coprecipitation method preparation corrosion magnetic halloysite nanotubes (HNTS-Fe 3o 4)
2g halloysite nanotubes particle is dispersed in the dilution heat of sulfuric acid of 100mL2mol/L, after ultrasonic, in 60 ℃ of water-bath magnetic agitation 12h, filter, with a large amount of distilled water washs to PH=7,50 ℃, vacuum is dry, obtains the corrosion halloysite nanotubes (HNTS) of the rear dilatation of inner wall section corrosion.
Corrosion halloysite nanotubes, FERRIC CHLORIDE ANHYDROUS, Iron dichloride tetrahydrate are dissolved in 200mL deionized water according to mass ratio 0.2:0.69:0.51, add after the ultrasonic dispersion of polyvinyl alcohol (PVA) of 5wt% (take mixture total mass as benchmark), under nitrogen protection, magnetic agitation 1h in 60 ℃ of water-baths; 12mL strong aqua is added dropwise to said mixture, control time for adding is 30min, the pH value of rear regulator solution is 11, rising temperature to 80 ℃, keeps aging 4h, finishes reaction, thing to be mixed carries out magnetic resolution with magnet after being chilled to room temperature, with deionized water and dehydrated alcohol, respectively wash 3 times afterwards, vacuum-drying at 60 ℃, obtains HNTS-Fe 3o 4nanotube.
(2) preparation of the magnetic halloysite nanotubes (MH-C=C) of the two keys of finishing
Get corrosion halloysite Magnetic nano-pipe 1g and add 30mL dry toluene; ultrasonic 30min; add again 3mL to remove the methacrylic acid (MMA) of stopper; under nitrogen protection; in 70 ℃ of backflow 24h; reaction finishes with magnet, to carry out separation afterwards, respectively washs 3 times successively, and be dried in 60 ℃, vacuum with toluene, dehydrated alcohol.The magnetic halloysite nanotubes (MH-C=C) of the two keys of finishing that obtain can well be dissolved in the organic solvents such as ethanol, chloroform, acetonitrile.
(3) preparation of magnetic halloysite molecularly imprinted polymer (MH-MIP)
First, get template molecule 2,4 dichlorophenoxyacetic acid 0.11g (0.5mmol) and add 10mL acetonitrile and 0.17mL (2mmol) monomer 4-vinylpridine (4-VP) self-assembly 12h at 4 ℃, obtain pre-assembled solution.
Then, by magnetic halloysite nanotubes (MH-C=C), the 1.9mL(20mmol of the two keys of the 0.2g finishing of preparation in step (2)) linking agent Vinylstyrene (DVB) joins pre-assembled solution, letting nitrogen in and deoxidizing, stir the mixed solution that the polyvinylpyrrolidone adding after 30min by 0.1g is dissolved in the acetonitrile of 30mL and form small molecular weight polymer at 0.02g initiator azo-bis-isobutyl cyanide (AIBN) prepolymerization reaction 5h at 50 ℃, being warmed up to 60 ℃ continues, after reaction 20h, to continue to be warmed up at 80 ℃ and react 3h.After reaction finishes, be cooled to room temperature, with magnet, carry out separation, with methyl alcohol, wash away the complete monomer of unreacted and linking agent, 60 ℃, vacuum is dry.
Finally use methyl alcohol: mixed solution Soxhlet acetic acid=9:1(V/V) is extracted template molecule 2,4 dichlorophenoxyacetic acid is removed, until detect without template molecule and wash out and stop wash-out by high performance liquid phase.Elution time is 48h.Make the molecularly imprinted polymer on magnetic halloysite nanotubes surface leave hole.60 ℃, last vacuum is dry.
MH-NIP preparation method is consistent with preparation MH-MIP method and consumption, but does not add template molecule.
Above-mentioned synthetic magnetic halloysite nanotubes marking Molecularly Imprinted Polymer is carried out to Infrared Characterization, as in the infared spectrum of Fig. 1 3693 and 3622cm -1absorption peak belong to the hydroxyl peak of halloysite nanotubes inside, 560 and 480cm -1absorption peak belong to iron oxygen absorption peak, 1600cm -1absorption peak proved that the magnetic halloysite nanotubes that two keys are modified successfully makes, 2900cm -1the absorption peak explanation polymkeric substance of left and right is successfully wrapped in magnetic halloysite nanotubes surface: Fig. 2 is known, left side halloysite internal diameter is 20~25nm, external diameter is 40~45nm, the Z 250 ball particle 15~20nm on surface, thickness after the coated polymer of the right is 35~40nm: in Fig. 3, a curve is pure ferriferrous oxide particles, and b curve is halloysite ferriferrous oxide nano pipe.Between 20 °~70 °, can know six characteristic peak (2 θ=30.15 seeing Z 250 2 θ
Figure BDA0000424601240000075
, 35.54
Figure BDA0000424601240000076
, 43.21
Figure BDA0000424601240000071
, 53.41
Figure BDA0000424601240000072
, 57.13
Figure BDA0000424601240000073
, and 62.34
Figure BDA0000424601240000074
) in magnetic ferroferric oxide and magnetic ferroferric oxide halloysite nanotubes mixture peak position in (220), (311), (400), (422), (511), and (440) occur, yet, magnetic ferroferric oxide halloysite nanotubes is in 2 θ=12 °, and 21 °, the Shang You peak, position of 25 ° is because halloysite starting material cause.Illustrate that magnetic particle is successfully embedded in halloysite inside.
Embodiment 2
(1) coprecipitation method preparation corrosion magnetic halloysite nanotubes (HNTS-Fe 3o 4)
2g halloysite nanotubes particle is dispersed in the dilution heat of sulfuric acid of 100mL 2mol/L, after ultrasonic, in 60 ℃ of water-bath magnetic agitation 12h, filter, with a large amount of distilled water washs to PH=7,50 ℃, vacuum is dry, obtains the corrosion halloysite nanotubes (HNTS) of the rear dilatation of inner wall section corrosion.
Corrosion halloysite nanotubes, Iron(III) chloride hexahydrate, ferrous sulfate are dissolved in 200mL deionized water according to mass ratio 0.25:0.466:0.3, the ultrasonic dispersion of Macrogol 2000 (PEG-2000) that adds 5wt% (take mixture total mass as benchmark), after under nitrogen protection, magnetic agitation 1h in 50 ℃ of water-baths; The strong aqua that is 28% by 12mL volume fraction is added dropwise to said mixture, controlling time for adding is 30 min, the pH value of rear regulator solution is 11, rising temperature to 80 ℃, keeps aging 4 h, finishes reaction, thing to be mixed carries out magnetic resolution with magnet after being chilled to room temperature, with deionized water and dehydrated alcohol, respectively wash 3 times afterwards, vacuum-drying at 60 ℃, obtains HNTS-Fe 3o 4nanotube.
(2) preparation of the magnetic halloysite nanotubes (MH-C=C) of the two keys of finishing
Get corrosion halloysite Magnetic nano-pipe 1g and add 30mL dry toluene; ultrasonic 30min; add again 3mL to remove the methacrylic acid (MMA) of stopper; under nitrogen protection; in 70 ℃ of backflow 24h; reaction finishes with magnet, to carry out separation afterwards, respectively washs 3 times successively, and be dried in 60 ℃, vacuum with toluene, dehydrated alcohol.The magnetic halloysite nanotubes (MH-C=C) of the two keys of finishing that obtain can well be dissolved in the organic solvents such as ethanol, chloroform, acetonitrile.
(3) preparation of magnetic halloysite molecularly imprinted polymer (MH-MIP)
First, get template molecule 2,4 dichlorophenoxyacetic acid 0.11g (0.5mmol) and add 10mL acetonitrile and 0.17mL (2mmol) to locate monomer 4-vinylpridine (4-VP) self-assembly 12h at 4 ℃ of stopper, obtain pre-assembled solution.
Then, by magnetic halloysite nanotubes (MH-C=C), the 1.9mL(20mmol of the two keys of the 0.2g finishing of preparation in step (2)) join pre-assembled solution except stopper linking agent Vinylstyrene (DVB), letting nitrogen in and deoxidizing, stir the mixed solution that the polyvinylpyrrolidone adding after 30min by 0.1g is dissolved in the acetonitrile of 30mL and form small molecular weight polymer at 0.02g initiator azo-bis-isobutyl cyanide (AIBN) prepolymerization reaction 5h at 50 ℃, being warmed up to 60 ℃ continues, after reaction 20h, to continue to be warmed up at 80 ℃ and react 3h.After reaction finishes, be cooled to room temperature, with magnet, carry out separation, with methyl alcohol, wash away the complete monomer of unreacted and linking agent, 60 ℃, vacuum is dry.
Finally use methyl alcohol: mixed solution Soxhlet acetic acid=9:1(V/V) is extracted template molecule 2,4 dichlorophenoxyacetic acid is removed, until detect without template molecule and wash out and stop wash-out by high performance liquid phase.Elution time is 48h, makes the molecularly imprinted polymer on magnetic halloysite nanotubes surface leave hole.60 ℃, last vacuum is dry.MH-NIP preparation method is consistent with preparation MH-MIP method and consumption, but does not add template molecule.
Embodiment 3
Magnetic halloysite nanometer molecular imprinting polymer to embodiment 1 carries out adsorptive capacity detection: process is as follows: by the magnetic halloysite structure nano molecularly imprinted polymer of the embodiment of 5mg 1, to put into the concentration of substrate of 5mL be 80mg/L 2, in 4-D solution, being placed on vibration on Clothoid type vibrator mixes, in oscillatory process respectively at 5min, 10min, 15min, 20min, 30min, 40min, 50min, 60min, during 80min different time interval, with magnet, carry out separation, get supernatant liquid, test absorbancy calculates the concentration after adsorption equilibrium, according to the concentration difference of front and back according to formula Q e=(C o-C e) * V/m, wherein C oand C ebe the starting point concentration of 2,4-D and the concentration after absorption, V is liquor capacity, and m is Polymer adsorption quality of materials.As shown in Figure 4, adsorption time comparatively fast just can reach adsorption equilibrium at 40min, can be calculated and obtains adsorptive capacity Q max=34.9mg/g.
Magnetic halloysite nanometer molecular imprinting polymer to embodiment 1 carries out equilibrium adsorption detection: process is as follows: get each 5mg of MH-MIP and MH-NIP in ground flask, add 2 of different concns (25-400mg/L), 4-D solution 5mL, in constant temperature oscillator, shake 24h, with magnet, carry out separation, get supernatant liquid, test absorbancy calculate the concentration after adsorption equilibrium, according to the concentration difference of front and back according to the concentration difference of front and back according to formula Q e=(C o-C e) * V/m, wherein C oand C ebe the starting point concentration of 2,4-D and the concentration after absorption, V is liquor capacity, and m is Polymer adsorption quality of materials.As shown in Figure 5, imprinted polymer Yu Fei imprinted polymer army is along with concentration rising adsorptive capacity increases.But can reach adsorption equilibrium under 400mg/L condition.Can be calculated and obtain adsorptive capacity Q.
The magnetic halloysite nanometer molecular imprinting polymer specificity of embodiment 1 is selected: get with phenoxy acetic acid and 4 – methyl-2-chlorophenoxyacetic acid of 2,4-D similar and test its specificity, compound concentration is the solution of 0.36mol/L.Accurately take MH-MIP and, each 5mg of MH-NIP is in ground flask, add respectively the above-mentioned solution of 2mL, in thermostat container at 25 ℃, after Static Adsorption 24h, with magnet, carry out separation, get supernatant liquid, test absorbancy calculates the concentration after adsorption equilibrium, obtains adsorptive capacity Q by following formula, obtain Qi, Qj in selection factor-alpha=Qi/Qj formula and represent that respectively molecularly imprinted polymer is to template molecule and substrate molecule adsorptive capacity separately according to the concentration difference of front and back.α is larger, and expression molecularly imprinted polymer is better to the selectivity of substrate molecule, and when α > 1.35, it has been generally acknowledged that imprinted polymer can be separated from blending ingredients by template molecule.Result shows to corrode magnetic halloysite molecularly imprinted polymer (MH-MIP) 2,4 dichlorophenoxyacetic acid is had to good selectivity.

Claims (7)

1. preparation is to 2,4-dichlorphenoxyacetic acid has the method for the magnetic halloysite molecularly imprinted polymer of specific adsorption, it is characterized in that, with sulfuric acid, halloysite nanotubes corrosion is obtained corroding halloysite nanotubes, described corrosion halloysite nanotubes and trivalent iron salt and divalent iron salt make magnetic halloysite nanotubes by coprecipitation method, described magnetic halloysite nanotubes and methacrylic acid react in toluene, obtain the magnetic halloysite nanotubes of the two keys of finishing; The magnetic halloysite nanotubes of the two keys of described finishing and polymerization single polymerization monomer and linking agent be take 2,4 dichlorophenoxyacetic acid after template is carried out polymerization, then remove 2,4 dichlorophenoxyacetic acid, obtain;
Described 2,4-dichlorphenoxyacetic acid, polymerization single polymerization monomer, linking agent three's mol ratio is 1:2~6:16~24, wherein, polymerization single polymerization monomer is one or more of 4-vinylpridine, 2-vinyl pyridine, vinyl benzyl chloride, and linking agent is Vinylstyrene or ethylene glycol dimethacrylate;
The two magnetic halloysite nanotubes of key of described finishing and the mass ratio of polymerization single polymerization monomer are 1:1~2;
The proportionlity of described magnetic halloysite nanotubes, toluene, methacrylic acid three usage quantity is 1g:25~35mL:3~8mL.
2. the method for claim 1, is characterized in that, the sulphuric acid soln that described corrosion halloysite nanotubes is is 0.5~2mol/L by concentration, under 55~65 ℃ of conditions, by halloysite nanotubes corrosion 12~15h, prepares.
3. the method for claim 1, it is characterized in that, described polymerization is first by polymerization single polymerization monomer and 2,4-dichlorphenoxyacetic acid carries out self-assembly 6~12h at 0~5 ℃, obtain assembling liquid, in described assembling liquid, add magnetic halloysite nanotubes and the linking agent of the two keys of finishing first at 45~52 ℃ of pre-polymerization 3~7h, then at 53~65 ℃ of polymerization 18~22h, then at 75~85 ℃ of further polyase 13~7h.
4. the method for claim 1, is characterized in that, described reaction is to stir 18~24h at 65~70 ℃.
5. the method for claim 1, is characterized in that, the described 2,4 dichlorophenoxyacetic acid that removes is to adopt methyl alcohol and the acetic acid mixed solvent that volume ratio is 8~9:1~2 to extract 1~2d.
6. the method for claim 1, is characterized in that, corrosion halloysite nanotubes, trivalent iron salt and divalent iron salt three's reaction mass ratio is 0.2~0.5:0.6~0.9:0.50.
7. the method for claim 1, is characterized in that, described coprecipitation method reaction conditions: first, at 50~60 ℃, react after 0.5~1h, regulating pH is 9~11, then at 80~90 ℃, aging 4~5h.
CN201310624108.3A 2013-11-28 2013-11-28 Preparation has the method for the magnetic halloysite molecularly imprinted polymer of specific adsorption to 2,4 dichlorophenoxyacetic acid Expired - Fee Related CN103613722B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201310624108.3A CN103613722B (en) 2013-11-28 2013-11-28 Preparation has the method for the magnetic halloysite molecularly imprinted polymer of specific adsorption to 2,4 dichlorophenoxyacetic acid

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201310624108.3A CN103613722B (en) 2013-11-28 2013-11-28 Preparation has the method for the magnetic halloysite molecularly imprinted polymer of specific adsorption to 2,4 dichlorophenoxyacetic acid

Publications (2)

Publication Number Publication Date
CN103613722A true CN103613722A (en) 2014-03-05
CN103613722B CN103613722B (en) 2015-09-30

Family

ID=50164449

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201310624108.3A Expired - Fee Related CN103613722B (en) 2013-11-28 2013-11-28 Preparation has the method for the magnetic halloysite molecularly imprinted polymer of specific adsorption to 2,4 dichlorophenoxyacetic acid

Country Status (1)

Country Link
CN (1) CN103613722B (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104844768A (en) * 2015-04-22 2015-08-19 中南大学 Preparation method and application of core-shell structure temperature sensitive magnetic protein imprinted microspheres
CN105038331A (en) * 2015-06-18 2015-11-11 成都石大力盾科技有限公司 Method for preparing Fe2O3-HNTs nano-hybrid material
CN106525948A (en) * 2016-10-31 2017-03-22 扬州大学 Preparation method and application of sensor for molecular imprinting detection of 2,4-d
CN108435147A (en) * 2018-05-16 2018-08-24 武汉霖泉环保科技有限公司 A kind of preparation method of magnetic material
CN111978469A (en) * 2019-05-21 2020-11-24 中国药科大学 Preparation and application of mycotoxin and concealed toxin magnetic halloysite nanotube/molecularly imprinted polymer

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102527349A (en) * 2011-11-28 2012-07-04 江苏大学 Magnetic composite material surface imprinting thermosensitive adsorbent, and preparation method and application thereof
CN102580696A (en) * 2012-02-20 2012-07-18 江苏大学 Preparation method of temperature sensitive adsorbent of halloysite magnetic composite material surface blotting

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102527349A (en) * 2011-11-28 2012-07-04 江苏大学 Magnetic composite material surface imprinting thermosensitive adsorbent, and preparation method and application thereof
CN102580696A (en) * 2012-02-20 2012-07-18 江苏大学 Preparation method of temperature sensitive adsorbent of halloysite magnetic composite material surface blotting

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
KIZHAKEKUTHIATHOTTIL MATHEW ANNAMMA,ET AL.: "Design of 2,4-dichlorophenoxyacetic acid imprinted polymer with high specificity and selectivity", 《MATERIALS SCIENCES AND APPLICATIONS》 *

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104844768A (en) * 2015-04-22 2015-08-19 中南大学 Preparation method and application of core-shell structure temperature sensitive magnetic protein imprinted microspheres
CN104844768B (en) * 2015-04-22 2017-09-29 中南大学 A kind of preparation method and applications of the Thermo-sensitive magnetic Western blotting microballoon of core shell structure
CN105038331A (en) * 2015-06-18 2015-11-11 成都石大力盾科技有限公司 Method for preparing Fe2O3-HNTs nano-hybrid material
CN106525948A (en) * 2016-10-31 2017-03-22 扬州大学 Preparation method and application of sensor for molecular imprinting detection of 2,4-d
CN106525948B (en) * 2016-10-31 2019-04-19 扬州大学 A kind of preparation method and application of molecular engram detection 2,4-d sensor
CN108435147A (en) * 2018-05-16 2018-08-24 武汉霖泉环保科技有限公司 A kind of preparation method of magnetic material
CN111978469A (en) * 2019-05-21 2020-11-24 中国药科大学 Preparation and application of mycotoxin and concealed toxin magnetic halloysite nanotube/molecularly imprinted polymer

Also Published As

Publication number Publication date
CN103613722B (en) 2015-09-30

Similar Documents

Publication Publication Date Title
CN103613722B (en) Preparation has the method for the magnetic halloysite molecularly imprinted polymer of specific adsorption to 2,4 dichlorophenoxyacetic acid
CN104231166B (en) A kind of preparation method of bionical artemisinin molecularly imprinted composite membrane
Lu et al. Flow injection chemiluminescence sensor based on core–shell magnetic molecularly imprinted nanoparticles for determination of chrysoidine in food samples
CN102977247B (en) Preparation method of magnetic functionalized graphene oxide based molecularly imprinted hybrid material
CN108620048A (en) The amine-modified magnetic microsphere preparation method and application of polyethyleneimine
Kan et al. Molecularly imprinted polymers microsphere prepared by precipitation polymerization for hydroquinone recognition
CN103965419B (en) A kind of separation, the magnetic blotting method for producing polymer of purification Ractopamine
CN103601847B (en) A kind of preparation method of Core-shell type magnetic surface trace nano composite material
CN103100377A (en) Green preparation method of magnetic molecular imprinting sorbent
CN105107482A (en) Preparation method for molecular imprinting material and molecular imprinting material prepared through preparation method
CN106699952B (en) A kind of preparation method of the magnetic imprinted polymer of phenyl boric acid fundamental mode
Chen et al. Microwave-assisted RAFT polymerization of well-constructed magnetic surface molecularly imprinted polymers for specific recognition of benzimidazole residues
CN102964542A (en) RAFT (Reversible addition-fragmentation chain transfer) polymerization preparation method of magnetic mesoporous molecular imprinted hybrid silicon spheres
CN103992450A (en) Method for preparing Cyhalothrin magnetic fluorescent molecularly imprinted material
Tan et al. Development of surface imprinted core–shell nanoparticles and their application in a solid-phase dispersion extraction matrix for methyl parathion
CN107200812A (en) A kind of preparation method of magnetic molecularly imprinted material
CN106040204B (en) A kind of magnetism micropore organic nanotube hybrid material and its preparation and application
CN105080512A (en) Preparation method and application of oxidized graphene based cadmium ion imprinted polymer
CN102489273B (en) Preparation method of magnetic beads of dendritic molecular imprinting polymer on surface of estrogenic nano silica gel
CN103232572B (en) Molecular imprinting polymer for roxarsone detection, and preparation method thereof
CN107090059A (en) A kind of preparation method of the molecular imprinted polymer on surface of aqueous phase application
Gong et al. Hydrazone-linked luminescent covalent organic frameworks based on AIE-active unit for acid vapour sensing
CN103980122A (en) Amphiphilic pillar [5] arene self-assembled vesicle and depolymerization reversibility and controllability control method thereof
Dolak Ion imprinted affinity Cryogels for the selective adsorption uranium in real samples
CN103599757B (en) The preparation method of a kind of magnetic temp-sensitive type surface strontium ion trace adsorbent

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20150930