CN101181791A - Method for preparing magnetic timber - Google Patents
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- CN101181791A CN101181791A CNA2007100663372A CN200710066337A CN101181791A CN 101181791 A CN101181791 A CN 101181791A CN A2007100663372 A CNA2007100663372 A CN A2007100663372A CN 200710066337 A CN200710066337 A CN 200710066337A CN 101181791 A CN101181791 A CN 101181791A
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Abstract
The invention provides a preparation method of a magnetic wood, which is characterized in that magnetic material Fe3O4 is synthesized to holes of the wood by using an in-situ chemical synthesize method of pretreatment, dipping with ferric salt solution, hydrolysis and drying to prepare the synthesized magnetic wood with better magnetic performance. The preparation method of the invention has simple operation and low cost and the magnetic wood prepared by the method show good physical and chemical performance, thereby having wider application scope, for example, being used for absorption and screening of electromagnetic wave, etc.
Description
Technical field:
The present invention relates to the preparation method of a kind of structure uniqueness, well behaved magnetic timber, this composite magnetic can be used to inhale fields such as ripple, electromagnetic shielding, extraordinary finishing, electronic packaging.
Background technology:
Along with the continuous development of science and technology, compoundization of timber become the focus of materialogy research field.The inanimate matter composite modification technology of timber also has bigger development at aspects such as improving strength of wood, humidity sensitive, hear resistance.Expansion timber functional modification field gives timber new functional, is the effective way that further improves the added value of timber.
Magnetic timber is by adding magnetic material in timber, making timber and magnetic functional characteristic reach a kind of composite of good combination.Material also demonstrates characteristics such as low-density, humidity control, acoustic absorption and electro-magnetic wave absorption except that having magnetic characteristic, be with a wide range of applications in fields such as inhaling ripple, electromagnetic shielding, electronic packaging, extraordinary finishing.At present, the preparation method of magnetic timber only limits to physical method the magnetic material and the wood composite that prepare, demonstrates than excellent characteristic.For example, Japanese patent laid-open 2001-118711 and Chinese patent prospectus CN 1906989A all disclose a kind of preparation method of magnetic timber, its preparation method is exactly that ferrite powder and environmental-protection type adhesive are mixed, and makes sandwich with timber again, thereby makes magnetic timber.J.Magn.Magn.Mater. in addition, 2007,310 (2), 1028-1029 (2007 310 volumes of magnet magnetic material journal the 2nd phase 1028-1029 page or leaf), paper " Experimental study on electromagnetic wave absorbing control ofcoating magnetic wood using agrooving process " has been reported another kind of magnetic timber, its preparation method is by punching on timber, in the hole, put into manganese-zinc ferrite, thus preparation magnetic composite wood.These preparation method's costs of now having reported are higher, technology is complicated, and the magnetic uniformity of magnetic timber is not good enough.
Summary of the invention:
The objective of the invention is, overcome the deficiency that prior art exists, a kind of method for preparing magnetic timber new, simple to operate, with low cost is provided.
Technical solution of the present invention is: use chemical cheaply in-situ synthesis to prepare magnetic timber.
Particular content of the present invention is: comprise composite magnetic ferrite in timber, it is characterized in that: the present invention generates magnetic ferrites by the in-situ chemical synthesis technique in timber pore, and its concrete operation is:
A, will through cleaning, wooden unit or wood chip after the oven dry be impregnated in the iron salt solutions, obtains prepreg, said iron salt solutions is Fe
3+And Fe
2+Mixed solution, promptly in ferric sulfate, ferrous sulfate, iron chloride, frerrous chloride, ferric nitrate, the ferrous nitrate any trivalent iron salt and any ferrous ion salt the combination mixed solution, the iron ion total concentration is 0.1～3mol/L, Fe
3+: Fe
2+Mol ratio be 1.0: 1～2.0: 1, the temperature of timber pickling is normal temperature～70 ℃, impregnation pressure 0.001～2MPa, dip time when raw material be 1～24 hour during for wood chip, dip time is 5～72 hours when raw material is wooden unit.
B, the prepreg that the A operation is obtained are transferred to hydrolysis in ammoniacal liquor or the sodium hydroxide solution, obtain the presoma of composite wood, when with the ammoniacal liquor hydrolysis, ammonia concn is 0.5～5mol/L, and when with the sodium hydroxide solution hydrolysis, concentration of sodium hydroxide solution is 0.01～2mol/L, hydrolysis temperature is normal temperature～50 ℃, pressure is 0.07～2MPa, hydrolysis time when raw material be 1～24 hour during for wood chip, when raw material is 5～72 hours during for wooden unit.
C, the composite wood precursor body that process B is obtained place drying device dry, thereby have obtained Fe compound
3O
4The magnetic composite wood, baking temperature is 50～200 ℃, pressure is 0.001～0.11MPa, be 10 minutes～12 hours drying time when for wood chip, is 10～48 hours when for wooden unit.
Compare with prior art, the present invention has advantages such as simple to operate, with low cost, and the magnetic timber of preparing demonstrates good physical and chemical performance, and magnetic has good uniformity, and has wider range of application.
Description of drawings
Fig. 1 is the x-ray diffraction pattern of the sample that obtains by this technology
Fig. 2 is the infrared spectrogram of dry pure timber
Fig. 3 is the infrared spectrogram of the sample that obtains by this technology
Fig. 4 is the hysteresis curve figure of the sample that obtains by this technology
The specific embodiment:
The present invention is with chemical synthesis process compound Fe in timber
3O
4Magnetic material makes timber have magnetic, prepares the material that has timber and magnetic material double grading simultaneously.
Weighing FeCl in proportion
3And FeCl
2Be mixed with Fe
3+And Fe
2+Mixed molysite solution, the iron ion total concentration is 0.12mol/L, Fe
3+: Fe
2+Mol ratio be 1.2: 1.0, after the dissolving in the fragrant cedar sawdust immersion solution after will cleaning, drying, dipping temperature is 30 ℃ fully, impregnation pressure is 0.1MPa, dip time is 3 hours.After taking out the preimpregnation wood chip, be impregnated in the ammonia spirit of 0.6mol/L hydrolysis again 3 hours, 25 ℃ of hydrolysis temperatures, hydrolysis pressure is 0.1MPa, takes out the back wood chip is put into the drying device drying, and baking temperature is 60 ℃, pressure is 0.01MPa, and the time is 12 hours, has promptly obtained Fe compound
3O
4Compound wood chip.
Weighing Fe2 (SO in proportion
4)
3And FeSO
4Be mixed with Fe
3+And Fe
2+Mixed molysite solution, the iron ion total concentration is 1.0mol/L, Fe
3+: Fe
2+Mol ratio be 1.5: 1.0, after the dissolving in the fragrant China fir piece immersion solution after will cleaning, drying, dipping temperature is 50 ℃ fully, impregnation pressure is 1.0MPa, dip time is 24 hours.After taking out the preimpregnation wooden unit, be impregnated in the ammonia spirit of 2.0mol/L hydrolysis again 24 hours, 35 ℃ of hydrolysis temperatures, hydrolysis pressure is 0.5MPa, takes out the back wooden unit is put into the drying device drying, and baking temperature is 100 ℃, pressure is 0.1MPa, and the time is 10 hours, has promptly obtained Fe compound
3O
4Compound block timber.
Embodiment 3
Weighing Fe (NO in proportion
3)
3And Fe (NO
3)
2Be mixed with Fe
3+And Fe
2+Mixed molysite solution, the iron ion total concentration is 2.0mol/L, Fe
3+: Fe
2+Mol ratio be 1.8: 1.0, after the dissolving in the immersion of the yellow jacket wood chip after will cleaning, the drying solution, dipping temperature is 60 ℃ fully, impregnation pressure is 1.5MPa, dip time is 5 hours.After taking out the preimpregnation wooden unit, be impregnated in the ammonia spirit of 4.0mol/L hydrolysis again 5 hours, 30 ℃ of hydrolysis temperatures, hydrolysis pressure is 1.0MPa, takes out the back wooden unit is put into the drying device drying, and baking temperature is 120 ℃, pressure is 0.05MPa, and the time is 1 hour, has promptly obtained Fe compound
3O
4Compound wood chip.
Embodiment 4
Weighing FeCl in proportion
3And FeSO
4Be mixed with Fe
3+And Fe
2+Mixed molysite solution, the iron ion total concentration is 2.5mol/L, Fe
3+: Fe
2+Mol ratio be 1.1: 1.0, after the dissolving in the immersion of the yellow jacket wooden unit after will cleaning, the drying solution, dipping temperature is 40 ℃ fully, impregnation pressure is 0.005MPa, dip time is 48 hours.After taking out the preimpregnation wooden unit, be impregnated in the sodium hydroxide solution of 0.02mol/L hydrolysis again 48 hours, 25 ℃ of hydrolysis temperatures, hydrolysis pressure is 1.5MPa, takes out the back wooden unit is put into the drying device drying, and baking temperature is 150 ℃, pressure is 0.1MPa, and the time is 40 hours, has promptly obtained Fe compound
3O
4Compound block timber.
Embodiment 5
Weighing Fe in proportion
2(SO
4)
3And FeCl
2Be mixed with Fe
3+And Fe
2+Mixed molysite solution, the iron ion total concentration is 2.8mol/L, Fe
3+: Fe
2+Mol ratio be 1.9: 1.0, after the dissolving in the immersion of the pine sawdust after will cleaning, the drying solution, dipping temperature is 65 ℃ fully, impregnation pressure is 0.002MPa, dip time is 10 hours.After taking out the preimpregnation wood chip, be impregnated in the sodium hydroxide solution of 0.1mol/L hydrolysis again 8 hours, 35 ℃ of hydrolysis temperatures, hydrolysis pressure is 0.08MPa, takes out the back wood chip is put into the drying device drying, and baking temperature is 180 ℃, pressure is 0.08MPa, and the time is 20 minutes, has promptly obtained Fe compound
3O
4Compound wood chip.
Embodiment 6
Weighing Fe in proportion
2(SO
4)
3And Fe (NO
3)
2Be mixed with Fe
3+And Fe
2+Mixed molysite solution, the iron ion total concentration is 0.5mol/L, Fe
3+: Fe
2+Mol ratio be 1.3: 1.0, after the dissolving in the immersion of the pine piece after will cleaning, the drying solution, dipping temperature is 70 ℃ fully, impregnation pressure is 1.8MPa, dip time is 24 hours.After taking out the preimpregnation wooden unit, be impregnated in the sodium hydroxide solution of 1.0mol/L hydrolysis again 12 hours, 45 ℃ of hydrolysis temperatures, hydrolysis pressure is 1.8MPa, takes out the back wooden unit is put into the drying device drying, and baking temperature is 120 ℃, pressure is 0.1MPa, and the time is 30 hours, has promptly obtained Fe compound
3O
4Compound block timber.
Embodiment 7
Weighing Fe (NO in proportion
3)
3And FeSO
4Be mixed with Fe
3+And Fe
2+Mixed molysite solution, the iron ion total concentration is 1.0mol/L, Fe
3+: Fe
2+Mol ratio be 1.7: 1.0, after the dissolving in the immersion of the Chinese hemlock spruce wood chip after will cleaning, the drying solution, dipping temperature is 30 ℃ fully, impregnation pressure is 0.9MPa, dip time is 20 hours.After taking out the preimpregnation wooden unit, be impregnated in the ammonia spirit of 3.0mol/L hydrolysis again 20 hours, 25 ℃ of hydrolysis temperatures, hydrolysis pressure is 0.8MPa, takes out the back wooden unit is put into the drying device drying, and baking temperature is 100 ℃, pressure is 0.09MPa, and the time is 10 hours, has promptly obtained Fe compound
3O
4Compound wood chip.
Weighing FeCl in proportion
3And Fe (NO
3)
2Be mixed with Fe
3+And Fe
2+Mixed molysite solution, the iron ion total concentration is 1.5mol/L, Fe
3+: Fe
2+Mol ratio be 1.4: 1.0, after the dissolving in the immersion of the pine piece after will cleaning, the drying solution, dipping temperature is 30 ℃ fully, impregnation pressure is 0.09MPa, dip time is 70 hours.After taking out the preimpregnation wooden unit, be impregnated in the sodium hydroxide solution of 0.8mol/L hydrolysis again 60 hours, 35 ℃ of hydrolysis temperatures, hydrolysis pressure is 0.1MPa, takes out the back wooden unit is put into the drying device drying, and baking temperature is 80 ℃, pressure is 0.1MPa, and the time is 46 hours, has promptly obtained Fe compound
3O
4Compound block timber.
Embodiment 9
Weighing Fe (NO in proportion
3)
3And FeCl
2Be mixed with Fe
3+And Fe
2+Mixed molysite solution, the iron ion total concentration is 0.5mol/L, Fe
3+: Fe
2+Mol ratio be 1.6: 1.0, after the dissolving in the immersion of the pine sawdust after will cleaning, the drying solution, dipping temperature is 40 ℃ fully, impregnation pressure is 0.15MPa, dip time is 22 hours.After taking out the preimpregnation wooden unit, be impregnated in the ammonia spirit of 1.2mol/L hydrolysis again 18 hours, 25 ℃ of hydrolysis temperatures, hydrolysis pressure is 0.12MPa, takes out the back wooden unit is put into the drying device drying, and baking temperature is 80 ℃, pressure is 0.005MPa, and the time is 10 hours, has promptly obtained Fe compound
3O
4Compound wood chip.
In laboratory research of the present invention, measured the x-ray diffraction pattern and the infrared spectrum of sample segment, accompanying drawing 1 is the x-ray diffraction pattern of the sample that obtains by this technology, as seen from the figure, and by this technology, compound Fe in timber
3O
4Magnetic material.Fig. 2 and Fig. 3 are respectively the infrared spectrograms of dry pure timber and the sample that obtains by this technology, from figure as can be known, sample by the preparation of in-situ chemical synthetic method has stronger physics chemical action between timber and the ferrite, illustrate that timber and ferrite are in conjunction with more firm.In the laboratory research, also measured the magnetic characteristic of sample, all samples all has certain magnetic, and Fig. 4 is the hysteresis curve figure of a sample obtaining by this technology, and from figure as can be known, sample has magnetic characteristic preferably.
Claims (1)
1. the preparation method of a magnetic timber comprises composite magnetic ferrite in timber, it is characterized in that: the present invention generates magnetic ferrites by the in-situ chemical synthesis technique in timber pore, and its concrete operation is:
A, will through cleaning, wooden unit or wood chip after the oven dry be impregnated in the iron salt solutions, obtains prepreg, said iron salt solutions is Fe
3+And Fe
2+Mixed solution, promptly in ferric sulfate, ferrous sulfate, iron chloride, frerrous chloride, ferric nitrate, the ferrous nitrate any trivalent iron salt and any ferrous ion salt the combination mixed solution, the iron ion total concentration is 0.1～3mol/L, Fe
3+: Fe
2+Mol ratio be 1.0: 1～2.0: 1, the temperature of timber pickling is normal temperature～70 ℃, impregnation pressure 0.001～2MPa, dip time when raw material be 1～24 hour during for wood chip, dip time is 5～72 hours when raw material is wooden unit.
B, the prepreg that the A operation is obtained are transferred to hydrolysis in ammoniacal liquor or the sodium hydroxide solution, obtain the presoma of composite wood, when with the ammoniacal liquor hydrolysis, ammonia concn is 0.5～5 mol/L, and when with the sodium hydroxide solution hydrolysis, concentration of sodium hydroxide solution is 0.01～2mol/L, hydrolysis temperature is normal temperature～50 ℃, pressure is 0.07～2MPa, hydrolysis time when raw material be 1～24 hour during for wood chip, when raw material is 5～72 hours during for wooden unit.
C, the composite wood precursor body that process B is obtained place drying device dry, thereby have obtained Fe compound
3O
4The magnetic composite wood, baking temperature is 50～200 ℃, pressure is 0.001～0.11MPa, be 10 minutes～12 hours drying time when for wood chip, is 5～48 hours when for wooden unit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNA2007100663372A CN101181791A (en) | 2007-10-31 | 2007-10-31 | Method for preparing magnetic timber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNA2007100663372A CN101181791A (en) | 2007-10-31 | 2007-10-31 | Method for preparing magnetic timber |
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| Publication Number | Publication Date |
|---|---|
| CN101181791A true CN101181791A (en) | 2008-05-21 |
Family
ID=39447288
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNA2007100663372A Pending CN101181791A (en) | 2007-10-31 | 2007-10-31 | Method for preparing magnetic timber |
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103692519A (en) * | 2013-12-19 | 2014-04-02 | 东北林业大学 | Method for in-situ growth of magnetic nanoparticles Fe3O4 on surface of wood |
| CN104400846A (en) * | 2014-10-22 | 2015-03-11 | 东北林业大学 | Preparation method of magnetic-response wood/Fe3O4 composite material |
| CN104842420A (en) * | 2015-05-15 | 2015-08-19 | 浙江农林大学 | Method for growing magnetic nanometer gamma-Fe2O3 on surface of bamboo wood at room temperature |
| CN105780584A (en) * | 2014-12-13 | 2016-07-20 | 广东轻工职业技术学院 | Magnetic paper and preparation method thereof |
| CN106553249A (en) * | 2016-12-07 | 2017-04-05 | 浙江农林大学 | Prepare the method and its timber of super-hydrophobic magnetotaxis wood surface |
| CN106625930A (en) * | 2016-12-28 | 2017-05-10 | 中南林业科技大学 | Phase-change energy storage heat-insulation solid wood and manufacturing method thereof |
| CN106827134A (en) * | 2017-02-10 | 2017-06-13 | 南京林业大学 | A kind of preparation method of the controllable magnetic timber of magnetic |
| CN108048034A (en) * | 2017-12-07 | 2018-05-18 | 南京林业大学 | A kind of preparation method of electromagnetic shielding material |
| CN109225343A (en) * | 2018-10-17 | 2019-01-18 | 华南理工大学 | A kind of delignification wood chip/Fe3O4Composite material and preparation method and application |
| CN111319108A (en) * | 2020-02-24 | 2020-06-23 | 北京林业大学 | Preparation method of magnetic light-transmitting wood energy storage material |
| CN113453524A (en) * | 2021-04-23 | 2021-09-28 | 中南林业科技大学 | Magnetic metal composite material based on bamboo-wood three-dimensional hole frame and preparation method and application thereof |
-
2007
- 2007-10-31 CN CNA2007100663372A patent/CN101181791A/en active Pending
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103692519A (en) * | 2013-12-19 | 2014-04-02 | 东北林业大学 | Method for in-situ growth of magnetic nanoparticles Fe3O4 on surface of wood |
| CN104400846A (en) * | 2014-10-22 | 2015-03-11 | 东北林业大学 | Preparation method of magnetic-response wood/Fe3O4 composite material |
| CN105780584A (en) * | 2014-12-13 | 2016-07-20 | 广东轻工职业技术学院 | Magnetic paper and preparation method thereof |
| CN104842420A (en) * | 2015-05-15 | 2015-08-19 | 浙江农林大学 | Method for growing magnetic nanometer gamma-Fe2O3 on surface of bamboo wood at room temperature |
| CN106553249A (en) * | 2016-12-07 | 2017-04-05 | 浙江农林大学 | Prepare the method and its timber of super-hydrophobic magnetotaxis wood surface |
| CN106625930B (en) * | 2016-12-28 | 2019-02-01 | 中南林业科技大学 | A kind of the heat preservation solid wood and its manufacturing method of phase-change accumulation energy |
| CN106625930A (en) * | 2016-12-28 | 2017-05-10 | 中南林业科技大学 | Phase-change energy storage heat-insulation solid wood and manufacturing method thereof |
| CN106827134A (en) * | 2017-02-10 | 2017-06-13 | 南京林业大学 | A kind of preparation method of the controllable magnetic timber of magnetic |
| CN108048034A (en) * | 2017-12-07 | 2018-05-18 | 南京林业大学 | A kind of preparation method of electromagnetic shielding material |
| CN108048034B (en) * | 2017-12-07 | 2021-02-26 | 南京林业大学 | Preparation method of electromagnetic shielding material |
| CN109225343A (en) * | 2018-10-17 | 2019-01-18 | 华南理工大学 | A kind of delignification wood chip/Fe3O4Composite material and preparation method and application |
| CN111319108A (en) * | 2020-02-24 | 2020-06-23 | 北京林业大学 | Preparation method of magnetic light-transmitting wood energy storage material |
| CN113453524A (en) * | 2021-04-23 | 2021-09-28 | 中南林业科技大学 | Magnetic metal composite material based on bamboo-wood three-dimensional hole frame and preparation method and application thereof |
| CN113453524B (en) * | 2021-04-23 | 2022-11-18 | 中南林业科技大学 | Magnetic metal composite material based on bamboo-wood three-dimensional hole frame and preparation method and application thereof |
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