CN101760959A - Compound modified biomass fibrilia and preparation method thereof - Google Patents
Compound modified biomass fibrilia and preparation method thereof Download PDFInfo
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- CN101760959A CN101760959A CN200910226703A CN200910226703A CN101760959A CN 101760959 A CN101760959 A CN 101760959A CN 200910226703 A CN200910226703 A CN 200910226703A CN 200910226703 A CN200910226703 A CN 200910226703A CN 101760959 A CN101760959 A CN 101760959A
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- fibrilia
- rare earth
- maleic anhydride
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Abstract
The invention relates to a compound modified biomass fibrilia and a preparation method thereof and develops a rare earth compound modified fibrilia, which is characterized in that maleic anhydride grafted polypropylene is grafted and coated on the outer surface of natural fibrilia modified by rare earth. The preparation method comprises the following steps of: impregnating the natural fibrilia in a certain rare earth solution at normal temperature or low temperature for 1-2 hours, filtering and drying; and then coating the maleic anhydride grafted polypropylene on the fibrilia treated by the rare earth by adopting an extruding method to obtain the compound modified biomass fibrilia. The compound modified method can effectively eliminate the problems of surface structural defects and impurities, change the surface polarity and the hydrophily, greatly improve the interface bonding force of the fibrilia and a polymer matrix material, can be expected to be made into a fibrilia/polymer composite material with strong interface bonding capability and excellent mechanical property and ensures that the modified natural fibrilia and a composite material thereof can be more widely applied to the field of buildings, vehicle trimmers, office furniture and the like. The modified method has the advantages of simple operation, scale, no pollution and environment friendlessness.
Description
Technical field
The invention belongs to the natural flax fibre of living beings and the preparation thereof of material and technical field of surface thereof, particularly a kind of surface recombination modified processing.The composite modified flax fibre material of invention, can effectively solve flax fibre surface texture defective, impurity, structural integrity and stability problem, and make the good interface that flax fibre can be further forms with polymeric matrix, thereby obtain widely, the flax fibre/polymer composites of mechanical property excellence, enlarge natural flax fibre Application Areas.
Background technology
Along with the constantly soaring and environmental protection pressures in short supply day by day, energy prices of international energy are increasing, national governments more and more pay attention to the energy-saving and environmental protection Study on Technology.Wherein one of most important measure is exactly the application of promoting lightweight, environmental friendliness, recyclable material.
Natural biological flax fibre/polymer composites is a kind of satisfy energy-saving and environmental protection, new material that requires such as recyclable.It can be widely used in fields such as vehicle, building, aircraft and routine office work articles for use.The natural biological flax fibre comprises low-cost bio materials such as hemp, ramie, flax, sisal hemp.Biomass fibrilia E-glass fibre, artificial carbon's fiber and thermoplas tic resin composite not only have advantage aspect environmental friendliness and recyclable the utilization, and wide material sources, in light weight, high-strength, Gao Mo and resistance to impact are strong.Be expected part and replace E-glass fibre, artificial carbon's fiber in the engineering field and the application of above-mentioned industry (vehicle, building etc.).Yet because there is the defect and impurity problem in natural biological flax fibre surface texture, and has stronger polarity, thereby flax fibre/polymer matrix composite interface compatibility is poor.For this reason, though researched and developed multiple natural fabric modification technology and method already, as: physical modification and chemical modification method.Wherein, physical modification is the chemical composition that does not change fiber, has mainly changed the certain physical characteristics of fiber, as laser high-energy ray radiation method, heat treating process and discharge process method etc.Method of chemical treatment comprises alkanisation facture, Graft Copolymerization of Cellulose method, acetylation facture and methods such as nitric acid and acetate mixed processing.Although the surface modifying method of flax fibre is a lot, yet still for fundamentally solving, the modification treatment effect has much room for improvement for itself and problems such as the polymeric matrix interface binding power is low, material property instability.Simple, cost is low, but the method for modifying of scale remains to be researched and developed.For this reason, under the Department of Science and Technology " 863 " high-new plan key project problem " research of alloy composite materials in the fiber reinforced polypropylene still " was supported, we had successfully developed a kind of biomass fibrilia rare earth composite modification material and method.This method is simple, and cost is low, but scale, and pollution-free, environmental friendliness.
Summary of the invention:
Flax fibre fault of construction and the impurity that the objective of the invention is to exist at existing natural biological flax fibre/polymer composites, flax fibre polarity is incompatible with the polymer polarity interface, interface binding power is low, finally cause problems such as natural biological flax fibre/polymer composites poor performance and unstable properties, first through scientific design and develop composite modified flax fibre and this modification flax fibre is simple, the preparation method of strong operability.Flax fibre surface hydroxyl quantity reduces after the modification, and the biomass fibrilia surface polarity lowers, and helps to improve the interface binding power of fiber and polymer-matrix; On the other hand, fibre structure is reformed, and not only the fiber surface defective greatly lowers, and has increased the combination interface of fiber and polymer, thereby can effectively improve flax fibre, polymer composites mechanical property.
The objective of the invention is to realize by following manner:
A kind of compound modified biomass fibrilia is that rare earth modified natural flax fibre outer surface is coated with maleic anhydride inoculated polypropylene.
Described rare earth modified natural flax fibre is meant natural flax fibre after the ultrasonic immersion of rare earth compound modifier solution, and filtering drying obtains.
Described coating is the coating that there is the skill of connecing reaction on the surface.
Preparation method of the present invention is: in the rare earth compound solution that natural flax fibre is immersed in, and after the ultrasonic immersion, filtering drying; Maleic anhydride inoculated polypropylene is melt into the fluid thing of thickness, the mode that adopts extrusion molding further is coated on natural flax fibre surface after rare earth is handled with maleic anhydride inoculated polypropylene, obtains rare earth/maleic anhydride inoculated polypropylene compound modified biomass fibrilia after the curing.
Rare earth compound solution adopts magnesium hydroxide to regulate the pH value to the 8-9 interval.
The mode of described extrusion molding coats maleic anhydride inoculated polypropylene and is meant maleic anhydride inoculated polypropylene is entered from single screw extrusion molding machine termination charging aperture, at extrusion temperature 175-185 ℃, maleic anhydride inoculated polypropylene fusion and become the fluid thing of thickness in single screw extrusion molding machine under the extrusion pressure 38-45bar condition; Simultaneously, the natural flax fibre after the rare earth surface treatment is relied on the traction of screw rod commentaries on classics power enter from another port, extrusion shaping machine side and carry out grafting and coat with the fluid thing of thickness is bonding.
With the above-mentioned material roll extrusion that coats through grafting, cooling, normal temperature cure, pelletizing obtain the composite modified biomass fibrilia of rare earth/maleic anhydride inoculated polypropylene.
The particularly preferred maleic anhydride inoculated polypropylene of the present invention, melt index 12-20g/10min, percent grafting: 2-3%.
The present invention has been owing to selected the low rare earth compound of electronegativity value for use, and is mixed with solution.Biomass fibrilia is handled in ultrasonic immersing in earth solution, and the fibrilia grafting that rare earth is handled coats maleic anhydride inoculated polypropylene again, obtains the composite modified natural flax fibre of rare earth/maleic anhydride inoculated polypropylene.Preferred rare earth compound weight content in solution is: 0.1%-0.5%.
Preferred ultrasonic immersion process is: compound concentration is the rare earth compound solution of 0.1%-0.5%, contains in the vessel, and biological flax fibre be impregnated in rare earth compound solution, and the impregnation process flax fibre is 1-2 hour under the ultrasonic vibration condition, filtration, air-dry.
Rare earth compound comprises rare earth oxide.Preferred lanthanum nitrate of the present invention or lanthana.Rare earth modified back flax fibre traction condition is: screw speed 70-80 rev/min.
The concrete preparation process of the present invention is:
With La (NO
3)
36H
2O dissolves in the hot water of 50-60 ℃ of degree, and be configured to the earth solution of certain mass concentration (scope is at 0.1%-0.5%), clean and dried ramee are put into the earth solution that configures, take out after sonic oscillation 1-2 hour, stand-by after 80 ℃ of-90 ℃ of vacuumizes.With maleic anhydride inoculated polypropylene from single screw extrusion molding machine termination throat-fed, at extrusion temperature 175-185 ℃, under the extrusion pressure 38-45bar condition, extrude the maleic anhydride inoculated polypropylene of viscosity flow state, and make it in extrusion to combine and to be coated on rare earth modified natural flax fibre surface, roll extrusion, cooling with natural flax fibre after the rare earth surface treatment, normal temperature cure, pelletizing obtain the composite modified natural flax fibre of rare earth/maleic anhydride inoculated polypropylene.
Among the present invention, combine for satisfying the good interface of flax fibre and polymer, inventor's design has also successfully been developed biomass fibrilia rare earth composite modification material and preparation method thereof.Biological flax fibre after the inventive method modification has following several big characteristics: the flax fibre surface impurity is removed, and the flax fibre surface polarity lowers, fibre structure reformation beam splitting, the fiber surface defective greatly lowers, fibre structure, stable performance, and processing method is nontoxic, harmless, environmental friendliness.
The present invention a kind of biomass fibrilia rare earth/maleic anhydride inoculated polypropylene composite modification material and method of simple, strong operability also be provided.The method of modifying technical process of invention is simple, and technological parameter is controlled, has ensured the uniformity of modification flax fibre material property.
Advantageous effect of the present invention is embodied in:
1, scientific design, effect is good.
In rare earth modified solution, the low rare earth element of electronegativity value will with the hydroxyl bonding on natural biological flax fibre surface, the hydroxyl quantity that this will reduce biological flax fibre surface has reduced the polarity of biological flax fibre, can improve the interface binding power between flax fibre and the non-polar polymer matrix; Simultaneously, because of rare earth element absorption be bonded in the flax fibre surface, thereby can fill up or improve the microstructure defective (micro-cracks that size is different) on flax fibre surface, improve the mechanical property (as: TENSILE STRENGTH etc.) of fiber itself.Thereby the enhancing effect when realizing flax fibre as the composite wild phase.On the other hand, because the rare earth atom electronegativity is extremely low, extremely strong chemical affinity is arranged, can be used as negative electricity central suction atom on every side, become the activated centre, therefore, absorption and the rare earth element that is bonded in the flax fibre surface occur with the form of active rare earth atom, combine with the maleic anhydride inoculated polypropylene that grafting coats better, form function admirable, constitutionally stable modification flax fibre.Thereby be expected greatly to improve the mechanical property that flax fibre strengthens polymer composites, enlarge the range of application of biomass fibrilia at automobile, building, space industry.The binding mechanism of interface science design is seen accompanying drawing 1.
2, structure is reformed, and modification flax fibre material property is stable.
Comprise that with existing method of chemical treatment alkanisation facture, Graft Copolymerization of Cellulose method, acetylation facture and nitric acid compares with methods such as acetate mixed processing; the present invention has not only improved the interface bond strength of fiber and polymer-matrix; and the fibre structure of having reformed effectively; make the fault of construction of natural flax fibre reduce greatly; and, the improvement of fibre structure and uniformity, the stability of fibre property structure have been realized better by the maleic anhydride inoculated polypropylene that coats.Thereby can solve flax fibre reinforced composite unstable properties problem effectively.It is a kind of surface recombination modified new method of biomass fibrilia with novelty.
3, composite modified, improve the reinforced composite mechanical property.
Flax fibre after rare earth modified, structure is reformed with the activated centre of rare earth atom formation, but is induced maleic anhydride inoculated polypropylene to coat, thereby is obtained composite modified flax fibre.Composite modified flax fibre can be used as the polymer composites that wild phase prepares its enhancing.Because composite modified flax fibre surface coats maleic anhydride inoculated polypropylene, thereby can constitute good compatible interface, and possess good adhesion characteristic with the macromolecular chain of polymer.Make that simultaneously wild phase is uniformly dispersed, thereby improve the stretching and the impact strength of reinforced composite.
4, cost is low, the technology simple controllable.
With more existing flax fibre surface treatment methods, to compare with the discharge process method as laser high-energy ray radiation method, the inventive method is simpler, and technological parameter is easy to control, and the technical process energy consumption is little, energy-conserving and environment-protective, cost is lower.
Description of drawings
The composite modified bonding mechanism schematic diagram of Fig. 1 biomass fibrilia rare earth
Fig. 2 a, Fig. 2 b are the rare earth modified front and back of flax fibre microstructure comparative analysis figure, before Fig. 2 a is rare earth modified, after Fig. 2 b is rare earth modified.
By Fig. 2 a, 2b contrast as seen, rare earth modified after, the flax fibre surface impurity is able to effective removal, fibre structure defective reduction, fibre structure reformation beam splitting.Improving fiber self intensity simultaneously, can greatly increase the faying face area and the interface bond strength of fiber and polymer.Thereby can effectively improve the whole mechanical property that flax fibre strengthens polymer matrix composite.
The rare earth modified front and back of Fig. 3 flax fibre infrared spectrum is formed comparative analysis figure.Among the figure: 1-is rare earth modified; The 2-acetylation is handled; The 3-hot alkali treatment; The 4-flax fibre that is untreated.As seen from the figure, rare earth modified, acetylation processing, hot alkali treatment all can lower surface impurity, but rare earth modified method effect is better.From 3420cm
-1The sharpening at peak, place, 1735cm
-1The disappearance at peak, 1320cm
-1And 1160cm
-1Peak value weakens, and all can find out rare earth modified structure and the composition that has improved former flax fibre biglyyer, and the hemicellulose in the fiber, pectin impurity disappear mutually.Therefore, the composite modified method of flax fibre rare earth of the present invention is than existing acetylation processing, hot alkali treatment better effects if.
The specific embodiment
Following examples are intended to illustrate the present invention rather than limitation of the invention further.
Embodiment 1:
1. take by weighing 2.667g lanthanum nitrate hexahydrate (La (NO
3)
36H
2O), the lanthanum nitrate hexahydrate that weighs up is dissolved in (50-60 ℃) in the 2Kg hot water under the middling speed magnetic agitation, continue to stir till lanthanum nitrate hexahydrate dissolves fully;
2. take by weighing 0.5Kg with the clear water rinsing and the ramee after drying, put into that the earth solution immersion treatment that configures was pulled out after 1-2 hour, drying;
3. take by weighing 1Kg maleic anhydride inoculated polypropylene (KRD series maleic anhydride inoculated polypropylene, Qinhuangdao Ke Ruida macromolecular material Co., Ltd, following examples together), fusion and bonding in single screw extrusion molding machine with the ramie after the rare earth processing, at extrusion temperature 175-185 ℃, under the extrusion pressure 38-45bar condition, rare earth modified ramee draws under 80 rev/mins of conditions of screw speed and enters extruder and coated by maleic anhydride inoculated polypropylene.
4. the rare earth grafting is coated flax fibre after composite modified through the roll extrusion uniform outer surface, cooling, normal temperature cure, drying obtains the composite modified natural flax fibre of rare earth/maleic anhydride inoculated polypropylene.
Embodiment 2:
1. take by weighing 6g lanthanum nitrate hexahydrate (La (NO
3)
36H
2O), the lanthanum nitrate hexahydrate that weighs up is dissolved in (50-60 ℃) in the 1.5Kg hot water under the middling speed magnetic agitation, continue to stir till lanthanum nitrate hexahydrate dissolves fully;
2. take by weighing 500g with the clear water rinsing and the ramee after drying, put into that the earth solution immersion treatment that configures was pulled out after 1-2 hour, drying;
3. take by weighing the 1Kg maleic anhydride inoculated polypropylene, fusion and bonding in single screw extrusion molding machine with the ramie after the rare earth processing, at extrusion temperature 175-185 ℃, under the extrusion pressure 38-45bar condition, rare earth modified ramee draws under 75 rev/mins of conditions of screw speed and enters extruder and coated by maleic anhydride inoculated polypropylene.
4. the rare earth grafting is coated flax fibre after composite modified through the roll extrusion uniform outer surface, cooling, normal temperature cure, drying obtains the composite modified natural flax fibre of rare earth/maleic anhydride inoculated polypropylene.
Embodiment 3:
1. take by weighing 13.33g lanthanum nitrate hexahydrate (La (NO
3)
36H
2O), the lanthanum nitrate hexahydrate that weighs up is dissolved in (50-60 ℃) in the 2Kg hot water under the middling speed magnetic agitation, continue to stir till lanthanum nitrate hexahydrate dissolves fully;
2. take by weighing 1Kg with the clear water rinsing and the ramee after drying, put into that the earth solution immersion treatment that configures was pulled out after 1-2 hour, drying;
3. take by weighing the 2Kg maleic anhydride inoculated polypropylene, fusion and bonding in single screw extrusion molding machine with the ramie after the rare earth processing, at extrusion temperature 175-185 ℃, under the extrusion pressure 38-45bar condition, rare earth modified ramee draws under 70 rev/mins of conditions of screw speed and enters extruder and coated by maleic anhydride inoculated polypropylene.
4. the rare earth grafting is coated flax fibre after composite modified through the roll extrusion uniform outer surface, cooling, normal temperature cure, drying obtains the composite modified natural flax fibre of rare earth/maleic anhydride inoculated polypropylene.
Claims (9)
1. a compound modified biomass fibrilia is characterized in that, rare earth modified natural flax fibre outer surface is coated with maleic anhydride inoculated polypropylene.
2. a kind of compound modified biomass fibrilia according to claim 1 is characterized in that, described rare earth modified natural flax fibre is meant natural flax fibre after the ultrasonic immersion of rare earth compound modifier solution, and filtering drying obtains.
3. a kind of compound modified biomass fibrilia according to claim 1 is characterized in that, described coating is the coating that there is the skill of connecing reaction on the surface.
4. preparation claim 1 described a kind of compound modified biomass fibrilia method is characterized in that, in the rare earth compound solution that natural flax fibre is immersed in, and after the ultrasonic immersion, filtering drying; Maleic anhydride inoculated polypropylene is melt into the fluid thing of thickness, the mode that adopts extrusion molding further is coated on natural flax fibre surface after rare earth is handled with maleic anhydride inoculated polypropylene, obtains rare earth/maleic anhydride inoculated polypropylene compound modified biomass fibrilia after the curing.
5. according to the described a kind of compound modified biomass fibrilia preparation method of claim 4, it is characterized in that rare earth compound comprises rare earth oxide.
6. according to the described a kind of compound modified biomass fibrilia preparation method of claim 4, it is characterized in that described rare earth compound weight content in solution is: 0.1%-0.5%.
7. according to the described a kind of compound modified biomass fibrilia preparation method of claim 4, it is characterized in that rare earth compound solution adopts magnesium hydroxide to regulate the pH value to the 8-9 interval.
8. according to the described a kind of compound modified biomass fibrilia preparation method of claim 4, it is characterized in that, the mode of described extrusion molding coats maleic anhydride inoculated polypropylene and is meant maleic anhydride inoculated polypropylene is entered from single screw extrusion molding machine termination charging aperture, at extrusion temperature 175-185 ℃, maleic anhydride inoculated polypropylene fusion and become the fluid thing of thickness in single screw extrusion molding machine under the extrusion pressure 38-45bar condition; Simultaneously, the natural flax fibre after the rare earth surface treatment is relied on the traction of screw rod commentaries on classics power enter from another port, extrusion shaping machine side and carry out grafting and coat with the fluid thing of thickness is bonding.
9. according to the described a kind of compound modified biomass fibrilia preparation method of claim 4, it is characterized in that the melt index 12-20g/10min of maleic anhydride inoculated polypropylene, percent grafting: 2-3%.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102251386A (en) * | 2011-03-31 | 2011-11-23 | 陈明思 | Environmentally friendly modified bast fiber containing functional structure, and preparation method thereof |
| WO2012087173A1 (en) * | 2010-12-20 | 2012-06-28 | Universidade Do Minho | Hybrid nanocomposite for aquatic media remediation and respective production method |
| CN108120670A (en) * | 2016-11-29 | 2018-06-05 | 上海大学 | The test of fiber resin composite material interface shearing performance and ameliorative way under high temperature |
-
2009
- 2009-12-23 CN CN2009102267035A patent/CN101760959B/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2012087173A1 (en) * | 2010-12-20 | 2012-06-28 | Universidade Do Minho | Hybrid nanocomposite for aquatic media remediation and respective production method |
| CN103492430A (en) * | 2010-12-20 | 2014-01-01 | 米尼翁大学 | Hybrid nanocomposite for aquatic media remediation and respective production method |
| CN102251386A (en) * | 2011-03-31 | 2011-11-23 | 陈明思 | Environmentally friendly modified bast fiber containing functional structure, and preparation method thereof |
| CN102251386B (en) * | 2011-03-31 | 2012-10-03 | 陈明思 | Environmentally friendly modified bast fiber containing functional structure, and preparation method thereof |
| CN108120670A (en) * | 2016-11-29 | 2018-06-05 | 上海大学 | The test of fiber resin composite material interface shearing performance and ameliorative way under high temperature |
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