CN104497362B - A kind of preparation method of cellulose/nanometer silicon nitride composite membrane - Google Patents
A kind of preparation method of cellulose/nanometer silicon nitride composite membrane Download PDFInfo
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- CN104497362B CN104497362B CN201410771765.5A CN201410771765A CN104497362B CN 104497362 B CN104497362 B CN 104497362B CN 201410771765 A CN201410771765 A CN 201410771765A CN 104497362 B CN104497362 B CN 104497362B
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Abstract
The present invention relates to a kind of preparation method of cellulose/nanometer silicon nitride composite membrane, it is characterised in that prepare the uniform water slurry system of modified nano silicon nitride first, control its mass fraction for 0.16% 0.8%；In above-mentioned system, then add alkali and urea by a certain percentage, prepare alkali/urea dicyandiamide solution；Mass fraction is under the conditions of 20 DEG C 4.5% cellulose dissolution in alkali/urea dicyandiamide solution, under room temperature, defrosting, high-speed stirred, evacuation and centrifugal degassing obtain silicon nitride and cellulose mixed solution；Cellulose/nanometer silicon nitride composite membrane is prepared using sol-gal process.This preparation method simple possible, it is easy to operate.In composite membrane, inorganic nano-particle is well dispersed, and two alternate have stronger interaction.Compound film dynamic performance and excellent transparency, and with thermal conductivity and ultraviolet reflection performance.Can extensively apply in fields such as product packaging, feature degradation materials.
Description
Technical field
The present invention relates to a kind of preparation method of cellulose/nanometer silicon nitride composite membrane, belongs to polymer matrix composite
Technical field.
Background technology
In recent years, with the development of cellulose dissolution technology, fibrination Porous materials such as aeroge, perforated membrane and porous are fine
Dimension etc. causes the great interest of people.Based on the loose structure characteristic of material, intersect with reference to nano science, materialogy, biology
The subjects such as, physics and bionics, using blending method, sol-gel process, graft process, template assemblies method and biomimetic mineralization etc.
Method, the excellent properties of cellulose itself is carried out advantage with the feature of inorganic nano material and is combined, and construction structure is stable, work(
Energy property is clear and definite, the cellulose/inorganic particle composite material of environment-friendly degradable, is becoming study hotspot both domestic and external.As fiber
Plain porous material and the Nanocomposites such as silica, calcium carbonate, montmorillonite, metal, metal oxide, rare earth, give which
The functions such as bionical, conductive, magnetic conduction, chemical catalysis, antibacterial, bio-sensing, higher barrier, optics, very big improve fiber
The added value of plain porous material, has expanded the range of application of cellulosic material.At present, to cellulose/inorganic particle composite material
Research on the one hand be devoted to studying new compound system, develop new functional material；On the other hand then focus primarily upon to fibre
Dimension element or the surface modification of inorganic nano-particle, increase the load capacity of fibrination Porous materials with this, reduce inorganic particulate and exist
The compatibility of reunion, raising inorganic particulate and cellulosic matrix in fibrination pore structure, realizes preferably playing material work(
The purpose of energy property.
Nano Si3N4Used as a kind of important ceramic material, itself has excellent mechanical performance, chemical stability, heat conduction
Property, wearability, dielectric properties and ultraviolet reflection performance, have been widely used in many fields.Currently to silicon nitride
Research major part is related to preparation, shaping and the sintering process optimization of nano-silicon nitride and silicon nitride film material, and silicon nitride and
Other inorganic material are mixed with composite ceramics；And the report of the research in terms of nano-silicon nitride to be applied to polymer and application
Less.
But nano-silicon nitride, the nano-silicon nitride of especially surface-modified and modification is compound with porous cellulose to prepare work(
The research of energy composite membrane and application have no report.
Content of the invention
It is an object of the invention to provide a kind of preparation method of cellulose/nanometer silicon nitride composite membrane.The film is removed with excellent
In the mechanical property of general regenerated cellulose film, also higher thermal conductivity and the reflectivity to ultraviolet.This method simply may be used
OK, it is easy to operate.The composite membrane of preparation can be extensively applied in fields such as product packaging, feature degradation materials.
For achieving the above object, the present invention is adopted the following technical scheme that：
A kind of preparation method of cellulose/nanometer silicon nitride composite membrane, methods described comprise the steps：
(1) moditied processing is carried out to nano silicon nitride silicon face, in the polyvinyl acetate chain of its surface grafting partial alcoholysis；
(2) the modified nano silicon nitride particle by mass fraction for 0.16%-0.8% is added in deionized water, through machinery
Stirring, the ultrasonically treated water slurry for being allowed to form homogeneous transparent；
(3) certain alkali and urea are added in the water slurry system of modified nano silicon nitride, according to alkali/urea/water
Extra fine quality is than preparing cellulose solvent；
(4) cellulose is added in the alkali containing modified nano silicon nitride/urea/water solution system, control its quality to divide
Number is 4.5%, then is placed in freeze overnight in -20 DEG C of refrigerator.Take out and thaw, strong mechanical agitation obtains being dispersed with silicon nitride
Cellulose solution；
One kind wherein in cellulose chemistry slurry, people's fibre slurry, cotton, microcrystalline cellulose or alpha-cellulose.Modified Nano nitrogen
The mass ratio of SiClx and cellulose is 1: 49-1: 9.
(5) by after the alkali containing modified nano silicon nitride and cellulose/urea/water solution centrifugation removing bubble, adopt
Sol-gel process film forming in coagulating bath by cellulose solution, washing remove residual solvent, and drying at room temperature obtains cellulose/receive
Rice silicon nitride composite membrane.
It is an advantage of the current invention that：
(1) nano-silicon nitride of the polyvinyl acetate chain through surface grafting partial alcoholysis that the present invention is provided can be in water
The middle dispersion for forming clear homogeneous, the interaction of modified nano silicon nitride and cellulose are stronger, and inorganic nano-particle contains
When amount is higher, remain in composite membrane relatively evenly disperse；
(2) good mechanical performance of the composite membrane that the present invention is provided, stress-strain analysis show, when silicon nitride quality is divided
When number is for 8%, the tensile strength of composite membrane reaches 116.7MPa, and Young's modulus is 6.5GPa, and elongation at break is 7.4%；When
When silicon nitride mass fraction is 10%, the tensile strength of composite membrane reaches 112.9MPa, and Young's modulus is 6.9GPa, extension at break
Rate is 4.3%；The comprehensive mechanical property of composite membrane is superior to RCF regenerated cellulose film；
(3) transparency of composite membrane prepared by the present invention is good, when silicon nitride mass fraction is 10%, it is seen that photaesthesia ripple
At long 550nm, transmitance still reaches 60.6% (thickness is 0.06mm)；
(4) composite membrane that the present invention is obtained has certain feature, and when silicon nitride mass fraction is 10%, composite membrane is led
It is 40.2% (thickness is 0.06mm) that hot coefficient is the ultraviolet reflectivity at 0.1203W/m k, 380nm；
(5) the preparation simple possible that the present invention is provided, it is easy to operate, widened the application of nano-silicon nitride, gives
The new feature of regenerated cellulose film, the composite membrane of preparation can be wide in fields such as product packaging, feature degradation materials
General application.
Description of the drawings
Fig. 1：Impact of the nano silicon nitride silicone content to composite membrane light transmission rate,
Fig. 2：Impact of the nano silicon nitride silicone content to composite membrane ultraviolet reflection rate.
Specific embodiment
Embodiment 1
(1) chemical grafting treated of nano-silicon nitride is processed
Take the nano Si of 1g drying3N4The burning equipped with 100ml ethanol is added sequentially to 10ml VTES
In bottle, under 400W power, ultrasound 20min, makes Si3N4Fully dispersed, then in flask, 10ml ammoniacal liquor is added, machinery at 40 DEG C
Stirring reaction 40h.Under conditions of rotating speed is 7000r/min, centrifugal treating obtains the vinylated Si in surface for 3 times3N4Product,
48h is washed in apparatus,Soxhlet's, is vacuum dried 24h at 40 DEG C afterwards, that is, is obtained the vinylated Si in pure surface3N4.Take matter
Amount is than the vinylated Si for 1: 53N4It is scattered in methyl alcohol with vinyl acetate, initiator B PO is added, at 65 DEG C, 4h is reacted,
Reaction obtains Si3N4- PVAc product.The fully dispersed products therefrom of a certain amount of methyl alcohol is added in system, is simultaneously heated to 70 DEG C,
Add appropriate NaOH again in system, accelerate stirring and promote alcoholysis.Exchange of solvent is carried out with water to methyl alcohol, centrifuge washing 3 times, i.e.,
The Si of vinyl acetate of the prepared surface grafting through partial alcoholysis3N4, quantitatively it is diluted to the specific nano-silicon nitride moisture for containing admittedly and dissipates
Liquid.
(2) preparation of cellulose/nanometer silicon nitride composite membrane
Lithium hydroxide and urea are added in the aqueous dispersions of above-mentioned silicon nitride, according to LiOH/urea/H2The mass ratio of O
Solvent is prepared for 7: 12: 80.4；9g cotton linter is added after fully dissolving, after glass bar stirs, be placed in -20 DEG C of refrigerator
Freeze overnight.Take out normal temperature unfreezing, consumingly mechanical agitation obtain transparent and homogeneous the cellulose for being dispersed with nano-silicon nitride molten
Liquid, the mass fraction of cellulose is 4.5%；Rotating speed is centrifuged degassing process 10min for 8000r/min；Then, solution is fallen in glass
In glass plate, control thickness pushes away film, is placed in Na together with glass plate2SO4/H2SO4Coagulating bath in, at 20 DEG C keep 5min, composite membrane
Separate out；After deionized water washes away solvent, composite membrane is fixed on polyfluortetraethylene plate, air drying, finally gives to dry and put down
Whole cellulose/nanometer silicon nitride composite membrane.
Embodiment 2
(1) chemical grafting treated of nano-silicon nitride is processed
Take the nano Si of 2g drying3N4The burning equipped with 300ml ethanol is added sequentially to 20ml VTES
In bottle, under 400W power, ultrasound 20min, makes Si3N4Fully dispersed, then in flask, 30ml ammoniacal liquor is added, machinery at 40 DEG C
Stirring reaction 40h.Under conditions of rotating speed is 7000r/min, centrifugal treating obtains the vinylated Si in surface for 3 times3N4Product,
48h is washed in apparatus,Soxhlet's, is vacuum dried 24h at 40 DEG C afterwards, that is, is obtained the vinylated Si in pure surface3N4.Take matter
Amount is than the vinylated Si for 1: 53N4It is scattered in methyl alcohol with vinyl acetate, initiator A BVN is added, reacts at 60 DEG C
4h, reaction obtain Si3N4- PVAc product.The fully dispersed products therefrom of a certain amount of methyl alcohol is added in system, is simultaneously heated to 70
DEG C, then appropriate KOH is added in system, accelerate stirring and promote alcoholysis.Exchange of solvent is carried out with water to methyl alcohol, centrifuge washing 3 times,
The Si of surface grafting vinyl acetate through partial alcoholysis is obtained3N4, quantitatively it is diluted to the specific nano-silicon nitride moisture for containing admittedly
Dispersion liquid.
(2) preparation of cellulose/nanometer silicon nitride composite membrane
NaOH and urea are added in the aqueous dispersions of above-mentioned silicon nitride, according to NaOH/urea/H2The mass ratio of O
Solvent is prepared for 7: 12: 81, after fully dissolving, add the artificial paper pulp of 23g, after glass bar stirs, the mass fraction of cellulose
For 4.5%；It is placed in freeze overnight in -20 DEG C of refrigerator.Normal temperature unfreezing is taken out, consumingly mechanical agitation obtains dividing for transparent and homogeneous
Dissipating has the cellulose solution of nano-silicon nitride, and rotating speed is centrifuged degassing process 10min for 8000r/min；Then, solution is fallen in glass
In glass plate, control thickness pushes away film, is placed in the coagulating bath of absolute ethyl alcohol together with glass plate, keeps 10min at 20 DEG C, and composite membrane is analysed
Go out；After deionized water washes away solvent, composite membrane is fixed on polyfluortetraethylene plate, air drying, finally gives dried flat
Cellulose/nanometer silicon nitride composite membrane.
Embodiment 3
(1) chemical grafting treated of nano-silicon nitride is processed
Take the nano Si of 0.5g drying3N4It is added sequentially to equipped with 100ml ethanol with 5ml VTES
In flask, under 400W power, ultrasound 20min, makes Si3N4Fully dispersed, in flask, then add 10ml ammoniacal liquor, machine at 40 DEG C
Tool stirring reaction 40h.Under conditions of rotating speed is 6000r/min, centrifugal treating obtains the vinylated Si in surface for 3 times3N4Product,
48h is washed in apparatus,Soxhlet's, is vacuum dried 24h at 40 DEG C afterwards, that is, is obtained the vinylated Si in pure surface3N4.Take
Mass ratio is 1: 5 vinylated Si3N4It is scattered in methyl alcohol with vinyl acetate, initiator DCP is added, reacts at 165 DEG C
4h, reaction obtain Si3N4- PVAc product.The fully dispersed products therefrom of a certain amount of methyl alcohol is added in system, is simultaneously heated to 70
DEG C, then the KOH/ methanol solution for adding dissolving good in system, accelerate stirring and promote alcoholysis.Solvent friendship is carried out to methyl alcohol with water
Change, centrifuge washing 3 times, that is, the Si of vinyl acetate of the surface grafting through partial alcoholysis is obtained3N4, quantitatively it is diluted to and specific contains admittedly
Nano-silicon nitride aqueous dispersions.
(2) preparation of cellulose/nanometer silicon nitride composite membrane
NaOH, urea and thiocarbamide are added in the aqueous dispersions of above-mentioned silicon nitride, according to NaOH/urea/sulphur
The mass ratio of urea/water is 7: 7: 10: 76 preparation solvents, adds 9.5g chemical pulp, after glass bar stirs, put after fully dissolving
Freeze overnight in -20 DEG C of the refrigerator.Normal temperature unfreezing is taken out, what consumingly mechanical agitation obtained transparent and homogeneous is dispersed with a nanometer nitrogen
The cellulose solution of SiClx, the mass fraction of cellulose is 4.5%；Rotating speed is centrifuged degassing process 10min for 8500r/min；So
Afterwards, solution is fallen on glass plate, control thickness pushes away film, is placed in Na together with glass plate2SO4/H2SO4Coagulating bath in, at 20 DEG C
5min is kept, composite membrane is separated out；After deionized water washes away solvent, composite membrane is fixed on polyfluortetraethylene plate, air drying,
Finally give the cellulose/nanometer silicon nitride composite membrane of dried flat.
Embodiment 4
(1) chemical grafting treated of nano-silicon nitride is processed
Take the nano Si of 0.2g drying3N4The burning equipped with 50ml ethanol is added sequentially to 2ml VTES
In bottle, under 400W power, ultrasound 20min, makes Si3N4Fully dispersed, then in flask, 3ml ammoniacal liquor is added, machinery at 40 DEG C
Stirring reaction 40h.Under conditions of rotating speed is 7000r/min, centrifugal treating obtains the vinylated Si in surface for 3 times3N4Product,
48h is washed in apparatus,Soxhlet's, is vacuum dried 24h at 40 DEG C afterwards, that is, is obtained the vinylated Si in pure surface3N4.Take matter
Amount is than the vinylated Si for 1: 53N4It is scattered in methyl alcohol with vinyl acetate, initiator B PO is added, at 65 DEG C, 4h is reacted,
Reaction obtains Si3N4- PVAc product.The fully dispersed products therefrom of a certain amount of methyl alcohol is added in system, is simultaneously heated to 70 DEG C,
Add appropriate LiOH again in system, accelerate stirring and promote alcoholysis.Exchange of solvent is carried out with water to methyl alcohol, centrifuge washing 3 times, i.e.,
The Si of vinyl acetate of the prepared surface grafting through partial alcoholysis3N4, quantitatively it is diluted to the specific nano-silicon nitride moisture for containing admittedly and dissipates
Liquid.
(2) preparation of cellulose/nanometer silicon nitride composite membrane
NaOH and thiocarbamide are added in the aqueous dispersions of above-mentioned silicon nitride, according to the quality of NaOH/thiocarbamide/water
Than solvent being prepared for 9.5: 4.5: 86, add 9.8g absorbent cotton after fully dissolving, after glass bar stirs, be placed in -20 DEG C
Freeze overnight in refrigerator.Normal temperature unfreezing is taken out, consumingly mechanical agitation obtains the fibre for being dispersed with nano-silicon nitride of transparent and homogeneous
The plain solution of dimension, the mass fraction of cellulose is 4.5%；Rotating speed is centrifuged degassing process 10min for 9000r/min；Then, by solution
On glass plate, control thickness pushes away film, is placed in 5%H together with glass plate2SO4In solution coagulating bath, at 20 DEG C, 5min is kept, multiple
Close film to separate out；After deionized water washes away solvent, composite membrane is fixed on polyfluortetraethylene plate, air drying, finally gives dry
Dry smooth cellulose/nanometer silicon nitride composite membrane.
Claims (2)
1. a kind of preparation method of cellulose/nanometer silicon nitride composite membrane, it is characterised in that first nano silicon nitride silicon face is entered
Row moditied processing, prepares modified nano silicon nitride；Modified nano silicon nitride is well dispersed in deionized water, is configured to alkali urea
Dicyandiamide solution；Again cellulose is dissolved wherein at -20 DEG C, the cellulose that defrosting, high-speed stirred obtain being dispersed with silicon nitride is molten
Liquid；Cellulose/nanometer silicon nitride composite membrane is prepared using sol-gel process；Described modified nano silicon nitride is surface grafting
The nano-silicon nitride of the polyvinyl acetate chain of partial alcoholysis.
2. the preparation method of a kind of cellulose/nanometer silicon nitride composite membrane according to claim 1, it is characterised in that described
Cellulose be chemical pulp, people's fibre slurry, cotton, the one kind in microcrystalline cellulose or alpha-cellulose.
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| CN108610512B (en) * | 2018-04-28 | 2020-04-21 | 武汉理工大学 | Cellulose/layered boron nitride high-dielectric nano composite film and preparation method thereof |
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Effective date of registration: 20191225 Address after: 215000 No.68, Yuanjin Road, Zhangpu Town, Kunshan City, Suzhou City, Jiangsu Province Patentee after: SUZHOU HUAERDI ADHESIVE & HARDWARE PRODUCTS CO., LTD. Address before: College of chemistry and material engineering Jiangnan University No. 1800 214122 Jiangsu city of Wuxi Province Li Lake Avenue Patentee before: Jiangnan University |
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Address after: 215000 No.68 Yuanlu Road, Zhangpu Town, Kunshan City, Suzhou City, Jiangsu Province Patentee after: Suzhou Dingjia Precision Technology Co.,Ltd. Address before: 215000 No.68 Yuanlu Road, Zhangpu Town, Kunshan City, Suzhou City, Jiangsu Province Patentee before: SUZHOU HUAERDI ADHESIVE HARDWARE PRODUCT Co.,Ltd. |
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