CN104532663A - Composite-fiber flame-retardant paper and preparation method thereof - Google Patents
Composite-fiber flame-retardant paper and preparation method thereof Download PDFInfo
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- CN104532663A CN104532663A CN201410716512.8A CN201410716512A CN104532663A CN 104532663 A CN104532663 A CN 104532663A CN 201410716512 A CN201410716512 A CN 201410716512A CN 104532663 A CN104532663 A CN 104532663A
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Abstract
The invention discloses a composite-fiber flame-retardant paper and a preparation method thereof and relates to the technical field of papermaking. The composite-fiber flame-retardant paper comprises 30 to 50% of mineral fiber, 30 to 45% of dry plant fiber pulp, 5 to 10% of flame-retardant filler, 10 to 20% of filler and a small amount of starch. The preparation method comprises the following steps: blending the surface-treated mineral fiber, flame-retardant filler, plant fiber, starch, etc., and carrying out papermaking, pressing and drying so as to obtain the composite-fiber flame-retardant paper, wherein the flame-retardant filler is prepared from phosphoric acid, urea and magnesium aluminum hydrotalcite; and the mineral fiber is processed with cationic starch. The flame-retardant paper provided by the invention uses the mineral fiber to substitute part of plant fiber, has excellent flame retardant performance and has the following technical indicators: the continuous burning time of a paper sample is 0 second, the average ignition time is no more than 30s and the average carbonization length is no more than 45mm.
Description
Technical field
The present invention relates to pulp technology for making paper, particularly relate to a kind of composite fibre fire retardant papers and preparation method thereof.
Background technology
Paper is interweaved by string and forms, and its main component is cellulose, hemicellulose and a small amount of lignin, and these compositions are all inflammable constituents, and the burning-point of usual paper is at about 130 ~ 230 DEG C, and oxygen index (OI) is between 15 ~ 20.Paper base material often becomes the material of igniting of fire, and the economic loss caused because of its slight susceptibility to combustion is every year quite huge, and the anti-flammability of paper base material has become the performance indications of necessity of some Application Areass.
At present, existing paper and paper products fiber used are based on wood pulp fibre and straw pulp fiber, and China's timber resources is more in short supply, and traditional papermaking consumes a large amount of forest reserves and grass resource.And string is manufactured paper with pulp inflammable, the easy moisture absorption of the easy burn into of paper.In addition, the string paper grade (stock) water yield is large, produces a large amount of black liquor and waste water, and environmental pollution is serious, and wastewater treatment causes product cost to increase.
Publication number is CN101649575A, invention and created name for " ceramic fiber furnish composite paper " although patent document disclosed in ceramic fiber furnish composite paper there is certain flame retardant effect, but also do not reach the performance requirement of fire retardant papers, if improve the fire resistance of ceramic fibre composite sheet, then must add more ceramic fibre, now, the mechanical property of composite sheet has larger decline.
The paper that infusion process is produced need adsorb a large amount of fire retardants, large to the performance impact of paper own, so narrow application range.The fire retardant of rubbing method mainly concentrates on the surface of paper, and its surface flame-retardant effect is relatively better, but can not give paper internal ignition resistant, and uses a large amount of organic binders, so flame retardant effect is not ideal enough due to rubbing method.The method of adding fire retardant in slurry adds various water-insoluble fire retardant in slurry, and string mixing is copied into fire retardant papers, and this method is simple, but retardant load level is large, large on the physical property impact of paper.In slurry, additive process prepares fire retardant papers, has fire retardant and is evenly distributed, and affects the advantages such as little to the physical property of paper, after adding the agent of a small amount of retention principal curvature, significantly it can improve retention, reach flame retardant effect.Paper after flame treatment, can make it reach difficult combustion requirement, thus meet the requirement of industrial production and people's daily life.
Summary of the invention
The object of the invention is the technological deficiency for existing in prior art, and provide a kind of composite fibre fire retardant papers, it can meet fire resistance requirement, has again good mechanical property.
Another object of the present invention is to provide a kind of preparation method of composite fibre fire retardant papers.
The technical scheme adopted for realizing object of the present invention is:
A kind of composite fibre fire retardant papers, comprises mineral fibres 30 ~ 50% by weight percentage, string dry pulp 30 ~ 45%, fire-retardant filler 5 ~ 10%, filler 10 ~ 20%, a small amount of starch; Described fire-retardant filler is prepared by phosphoric acid, urea and magnalium hydrotalcite.
Further, the preparation method of described fire-retardant filler comprises the steps: phosphoric acid solution to pour in reactor to add thermal agitation, temperature is raised to 60 ~ 70 DEG C and adds urea, equitemperature adds magnalium hydrotalcite when being raised to 130 DEG C, insulation 10 ~ 15min, product is poured out, after solidification, pulverizing, obtains described fire-retardant filler.
Preferably, described phosphoric acid: urea: the ratio of quality and the number of copies of magnalium hydrotalcite is 1:0.85 ~ 0.95:0.15 ~ 0.35.
Preferably, described mineral fibres is wollastonite fibre, and fibre length is 1.0 ~ 5.0mm, and diameter is 3.0 ~ 6.0 μm.
A preparation method for described composite fibre fire retardant papers, comprises following operating procedure:
(1) pull an oar: string is put into beater and beat to beating degree between 30 ~ 50 ° of SR;
(2) add: in the paper pulp of pulling an oar through step (1), add mineral fibres successively, fire-retardant filler, starch solution, filler mix; Described starch solution adds in papermaking green end system blending chest and is mixed to get paper making pulp;
(3) shaping: will through step (2) mixed paper pulp on a papermaking machine according to 50 ~ 200g/m
2quantitatively manufacture paper with pulp, obtain described composite fibre fire retardant papers after pressing and drying; Described mineral fibres adopts cationic starch to process.
Further, the preparation method of described starch solution is:
The first starch solution that pre-treatment obtains concentration 15 ~ 29% is carried out to starch material;
By immersion method, described first starch solution is diluted and heated up, contain the described starch solution of different-grain diameter starch ball after obtaining swollen, described starch ball is that particle diameter is greater than 10 microns of mellow and full and uncracked starch spheroids.
Further, described step (2) also comprises:
Sticking agent is added and mixing and stirring with the amount of 0.1 ~ 1kg/ ton oven dry stock in the paper making pulp in described blending chest exit; Described sticking agent is cationic polyacrylamide, at least one in anionic polyacrylamide, acrylamide copolymer, polyamideepichlorohydrin and polyacrylamide-glyoxal polymer.
Further, described mineral fibres uses cationic starch to carry out surface-treated method to be: be added to the water by cationic starch, be mixed with the solution of 2 ~ 4g/L concentration; Be warming up to 60 DEG C, in solution, add mineral fibres, stir and mineral fiber surfaces is wrapped up by starch.
Preferably, described starch material is at least one in the derivative compound of ative starch, cationic starch, amphoteric starch and modified starch.
Preferably, described cationic starch is tertiary amine-type or quaternary amine type starch.
Compared with prior art, the invention has the beneficial effects as follows:
In composite fibre fire retardant papers of the present invention, with mineral fibres Substitute For Partial string, by the rational proportion of each component, when meeting fire resistance and requiring, there is good mechanical property.It is 0s that technical indicator reaches pattern after flame time, on average burn time≤32s, average char length≤57mm, there is excellent fire resistance.
Magnalium hydrotalcite is added in the process of phosphoric acid and urea synthesizing APP, reaction is carried out at the hole of magnalium hydrotalcite and surface, thus preparation APP/magnalium hydrotalcite composite flame-proof filler, make full use of the anti-flammability of APP and the anti-flammability of magnalium hydrotalcite, make fire-retardant filler have very high fire resistance.
The chemical agent that the present invention adds can be configured to stable solution with certain proportion, without the need to repeatedly adding separately, thus simplifying production procedure, reducing production cost.
Preparation method of the present invention adopts common paper technology directly to manufacture paper with pulp, and preparation method is simple, is easy to realize suitability for industrialized production.
Preparation method of the present invention, carry out surface treatment by cationic starch to mineral fibres, mineral fibres wraps up by starch, improve the adhesion between mineral fibres and string, meanwhile, cationic starch is paper grade (stock) reinforcing agent and retention agent, improves the quality of paper.
Detailed description of the invention
Below in conjunction with specific embodiment, the present invention is described in further detail.
Embodiment 1
1) fire-retardant filler is prepared by following method:
1. by 40kg concentration be 85% phosphoric acid pour in reactor, add thermal agitation, when temperature is raised to 60 DEG C, add 34kg urea, control heating rate 3 DEG C of min
-1.
2. when equitemperature is raised to 130 DEG C, add the magnalium hydrotalcite of 6kg, when keeping 130 DEG C, insulation 10min, pours out product.
3. product is solidified 2h in high-temperature cabinet at 210 DEG C, namely material pulverizing, excessively 320 mesh sieves after solidification are obtained fire-retardant filler.
2) preparation method of starch solution is:
The first starch solution that pre-treatment obtains concentration 15% is carried out to ative starch;
By immersion method, described first starch solution is diluted and heated up, contain the described starch solution of different-grain diameter starch ball after obtaining swollen, described starch ball is that particle diameter is greater than 10 microns of mellow and full and uncracked starch spheroids.
3) surface treatment of mineral fibres: tertiary amine-type cationic starch 64g is joined in 32L water, is mixed with the solution of 2g/L concentration.Be warming up to 60 DEG C, in solution, add mineral fibres 16kg, stir 0.5 hour, mineral fiber surfaces is wrapped up by starch.
4) pull an oar: paper pulp is put into the making beating of mill beater to certain beating degree; Described certain beating degree is 40 ° of SR;
5) add: in the paper pulp through making beating, add mineral fibres successively, fire-retardant filler, starch solution, filler mix; Described starch solution adds in papermaking green end system blending chest and is mixed to get paper making pulp; Sticking agent is added and mixing and stirring with the amount of 0.1kg/ ton oven dry stock in the paper making pulp in described blending chest exit; Described sticking agent is cationic polyacrylamide;
6) shaping: by mixed slurry on a papermaking machine according to necessarily quantitatively manufacturing paper with pulp, after pressing and drying, to obtain composite fibre fire retardant papers; Described is quantitatively 50g/m
2.
Embodiment 2
1) fire-retardant filler is prepared by following method:
1. by 20kg concentration be 85% phosphoric acid pour in reactor, add thermal agitation, when temperature is raised to 65 DEG C, add 13kg urea, control heating rate 3 DEG C of min-1.
2. when equitemperature is raised to 130 DEG C, add the magnalium hydrotalcite of 3kg, when keeping 130 DEG C, insulation 10min, pours out product.
3. product is solidified 2h in high-temperature cabinet at 210 DEG C, namely material pulverizing, excessively 320 mesh sieves after solidification are obtained fire-retardant filler.
2) preparation method of starch solution is:
The first starch solution that pre-treatment obtains concentration 20% is carried out to ative starch;
By immersion method, described first starch solution is diluted and heated up, contain the described starch solution of different-grain diameter starch ball after obtaining swollen, described starch ball is that particle diameter is greater than 12 microns of mellow and full and uncracked starch spheroids.
3) surface treatment of mineral fibres: tertiary amine-type cationic starch 50g is joined in 25L water, is mixed with the solution of 2g/L concentration.Be warming up to 60 DEG C, in solution, add mineral fibres 11kg, stir 0.5 hour, mineral fiber surfaces is wrapped up by starch.
4) pull an oar: paper pulp is put into the making beating of mill beater to certain beating degree; Described certain beating degree is 45 ° of SR;
5) add: in the paper pulp through making beating, add mineral fibres successively, fire-retardant filler, starch solution, filler mix; Described starch solution adds in papermaking green end system blending chest and is mixed to get paper making pulp; Sticking agent is added and mixing and stirring with the amount of 0.1kg/ ton oven dry stock in the paper making pulp in described blending chest exit; Described sticking agent is cationic polyacrylamide;
6) shaping: by mixed slurry on a papermaking machine according to necessarily quantitatively manufacturing paper with pulp, after pressing and drying, to obtain composite fibre fire retardant papers; Described is quantitatively 80g/m
2.
Embodiment 3
1) fire-retardant filler is prepared by following method:
1. by 50kg concentration be 85% phosphoric acid pour in reactor, add thermal agitation, when temperature is raised to 60 DEG C, add 42kg urea, control heating rate 3 DEG C of min-1.
2. when equitemperature is raised to 130 DEG C, add the magnalium hydrotalcite of 8kg, when keeping 130 DEG C, insulation 10min, pours out product.
3. product is solidified 2h in high-temperature cabinet at 210 DEG C, namely material pulverizing, excessively 320 mesh sieves after solidification are obtained fire-retardant filler.
2) preparation method of starch solution is:
The first starch solution that pre-treatment obtains concentration 29% is carried out to ative starch;
By immersion method, described first starch solution is diluted and heated up, contain the described starch solution of different-grain diameter starch ball after obtaining swollen, described starch ball is that particle diameter is greater than 10 microns of mellow and full and uncracked starch spheroids.
3) surface treatment of mineral fibres: tertiary amine-type cationic starch 100g is joined in 40L water, is mixed with the solution of 2.5g/L concentration.Be warming up to 60 DEG C, in solution, add mineral fibres 20kg, stir 0.5 hour, mineral fiber surfaces is wrapped up by starch.
4) pull an oar: paper pulp is put into the making beating of mill beater to certain beating degree; Described certain beating degree is 50 ° of SR;
5) add: in the paper pulp through making beating, add mineral fibres successively, fire-retardant filler, starch solution, filler mix; Described starch solution adds in papermaking green end system blending chest and is mixed to get paper making pulp; Sticking agent is added and mixing and stirring with the amount of 0.1kg/ ton oven dry stock in the paper making pulp in described blending chest exit; Described sticking agent is cationic polyacrylamide;
6) shaping: by mixed slurry on a papermaking machine according to necessarily quantitatively manufacturing paper with pulp, after pressing and drying, to obtain composite fibre fire retardant papers; Described is quantitatively 160g/m2.
Composite fibre fire retardant papers embodiment 1 ~ 3 obtained detects, and detects data as shown in table 1.
Table 1
Performance indications | Unit | Standard | Embodiment 1 | Embodiment 2 | Embodiment 3 |
After flame time | Second | ≤5 | 0 | 1 | 0 |
Burn the time | Second | ≤60 | 24 | 28 | 27 |
Char length | Millimeter | ≤115 | 39 | 43 | 37 |
Tensile index | N·m/g | 85 | 83 | 89 |
As can be seen from Table 1, composite fibre fire retardant papers of the present invention is with mineral fibres Substitute For Partial string, add fire-retardant filler simultaneously, have fire-retardant filler consumption few, flame retardant effect is obvious, and it is 0s that technical indicator reaches pattern after flame time, on average burn time≤30s, average char length≤45mm, has excellent fire resistance, and has good mechanical property.
The above is only the preferred embodiment of the present invention; it should be pointed out that for those skilled in the art, under the premise without departing from the principles of the invention; can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.
Claims (10)
1. a composite fibre fire retardant papers, is characterized in that, comprises mineral fibres 30 ~ 50% by weight percentage, string dry pulp 30 ~ 45%, fire-retardant filler 5 ~ 10%, filler 10 ~ 20%, a small amount of starch; Described fire-retardant filler is prepared by phosphoric acid, urea and magnalium hydrotalcite.
2. composite fibre fire retardant papers according to claim 1, it is characterized in that, the preparation method of described fire-retardant filler comprises the steps: phosphoric acid solution to pour in reactor to add thermal agitation, temperature is raised to 60 ~ 70 DEG C and adds urea, equitemperature adds magnalium hydrotalcite when being raised to 130 DEG C, insulation 10 ~ 15min, pours out product, obtains described fire-retardant filler after solidification, pulverizing.
3. composite fibre fire retardant papers according to claim 2, is characterized in that, described phosphoric acid: urea: the ratio of quality and the number of copies of magnalium hydrotalcite is 1:0.85 ~ 0.95:0.15 ~ 0.35.
4. composite fibre fire retardant papers according to claim 1, it is characterized in that, described mineral fibres is wollastonite fibre, and fibre length is 1.0 ~ 5.0mm, and diameter is 3.0 ~ 6.0 μm.
5. a preparation method for composite fibre fire retardant papers described in Claims 1 to 4 any one, is characterized in that, comprises following operating procedure:
(1) pull an oar: string is put into beater and beat to beating degree between 30 ~ 50 ° of SR;
(2) add: in the paper pulp of pulling an oar through step (1), add mineral fibres successively, fire-retardant filler, starch solution, filler mix; Described starch solution adds in papermaking green end system blending chest and is mixed to get paper making pulp;
(3) shaping: will through step (2) mixed paper pulp on a papermaking machine according to 50 ~ 200g/m
2quantitatively manufacture paper with pulp, obtain described composite fibre fire retardant papers after pressing and drying; Described mineral fibres adopts cationic starch to process.
6. the preparation method of composite fibre fire retardant papers according to claim 5, it is characterized in that, the preparation method of described starch solution is:
The first starch solution that pre-treatment obtains concentration 15 ~ 29% is carried out to starch material;
By immersion method, described first starch solution is diluted and heated up, contain the described starch solution of different-grain diameter starch ball after obtaining swollen, described starch ball is that particle diameter is greater than 10 microns of mellow and full and uncracked starch spheroids.
7. the preparation method of composite fibre fire retardant papers according to claim 5, it is characterized in that, described step (2) also comprises:
Sticking agent is added and mixing and stirring with the amount of 0.1 ~ 1kg/ ton oven dry stock in the paper making pulp in described blending chest exit; Described sticking agent is cationic polyacrylamide, at least one in anionic polyacrylamide, acrylamide copolymer, polyamideepichlorohydrin and polyacrylamide-glyoxal polymer.
8. the preparation method of composite fibre fire retardant papers according to claim 5, is characterized in that, described mineral fibres uses cationic starch to carry out surface-treated method to be: be added to the water by cationic starch, be mixed with the solution of 2 ~ 4g/L concentration; Be warming up to 60 DEG C, in solution, add mineral fibres, stir and mineral fiber surfaces is wrapped up by starch.
9. the preparation method of composite fibre fire retardant papers according to claim 6, it is characterized in that, described starch material is at least one in the derivative compound of ative starch, cationic starch, amphoteric starch and modified starch.
10. the preparation method of composite fibre fire retardant papers according to claim 8, it is characterized in that, described cationic starch is tertiary amine-type or quaternary amine type starch.
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CN106368069A (en) * | 2016-10-19 | 2017-02-01 | 中烟摩迪(江门)纸业有限公司 | Heating non-combustible cigarette paper and preparation method thereof |
CN106480773A (en) * | 2016-10-19 | 2017-03-08 | 中烟摩迪(江门)纸业有限公司 | A kind of high temperature resistant non-burning cigarette paper and preparation method thereof |
CN107142779A (en) * | 2017-06-29 | 2017-09-08 | 苏州安特实业有限公司 | A kind of fire retardant papers based on nano-cellulose whisker and microcapsules and preparation method thereof |
CN111005256A (en) * | 2019-12-06 | 2020-04-14 | 江苏悦达印刷有限公司 | Novel paper pulp for automatic printing and preparation method thereof |
CN112900157A (en) * | 2019-12-04 | 2021-06-04 | 山东鲁阳节能材料股份有限公司 | Ceramic fiber paper |
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Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
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CN106368069A (en) * | 2016-10-19 | 2017-02-01 | 中烟摩迪(江门)纸业有限公司 | Heating non-combustible cigarette paper and preparation method thereof |
CN106480773A (en) * | 2016-10-19 | 2017-03-08 | 中烟摩迪(江门)纸业有限公司 | A kind of high temperature resistant non-burning cigarette paper and preparation method thereof |
CN107142779A (en) * | 2017-06-29 | 2017-09-08 | 苏州安特实业有限公司 | A kind of fire retardant papers based on nano-cellulose whisker and microcapsules and preparation method thereof |
CN107142779B (en) * | 2017-06-29 | 2018-08-17 | 苏州安特实业有限公司 | A kind of fire retardant papers and preparation method thereof based on nano-cellulose whisker and microcapsules |
CN112900157A (en) * | 2019-12-04 | 2021-06-04 | 山东鲁阳节能材料股份有限公司 | Ceramic fiber paper |
CN111005256A (en) * | 2019-12-06 | 2020-04-14 | 江苏悦达印刷有限公司 | Novel paper pulp for automatic printing and preparation method thereof |
EP4400648A1 (en) * | 2023-01-16 | 2024-07-17 | JT International SA | Cigarette paper and a method of manufacture thereof |
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