CN103408701A - Method for preparing dry strength agent by ultraviolet-initiated polymerization - Google Patents
Method for preparing dry strength agent by ultraviolet-initiated polymerization Download PDFInfo
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Abstract
The invention provides a method for preparing an ultraviolet-initiated dry strength agent, which is characterized by comprising the following steps: mixing cationic starch and water, gelatinizing by heating, sequentially adding water, acrylamide, anionic monomer, crosslinkable monomer, chain transfer agent, other functional monomers and photoinitiator, heating to 70-95 DEG C in an oxygen-free environment, irradiating ultraviolet light on the reaction system to react for 1.5-2 hours, taking samples and carrying out viscosity testing at set intervals, stopping irradiating the ultraviolet light when the viscosity reaches 4000-9000 mP*s, adding a pH regulator to regulate the pH value to 4-6, and adding a free radical trapper to obtain the dry strength agent. The dry strength agent synthesized by the method has the characteristics of low consumption, favorable effect and low cost. The dry strength agent can be used in producing box making paper, corrugated base paper, enamelled paper, cone paper, special-type paper and many other types of paper, has the function of increasing the dry strength of paper, and especially has more obvious effect when using recovered wastepaper pulp as a paper making raw material.
Description
Technical field
The present invention relates to a kind of method that uv-light polymerization prepares Dry Strength Resin.
Background technology
Dry Strength Resin is in paper industry, to increase a class important chemical of paper strength, is generally used for the decline that filler or the caused paper intensity of low-grade fiber (as regenerated fibre) are added in compensation.Many water miscible, the superpolymer that can form hydrogen bonded with fiber can become Dry Strength Resin.
In recent years, China's waste paper resource utilization rises year by year, and development potentiality is huge.But the raising of the utilization ratio of waste paper means waste paper and recycles the increase of number of times, can cause declining to a great extent of paper strength index, so need, add Dry Strength Resin and strengthen paper strength.Along with constantly rising to the paper and Board demand in consumption market, pulled the rapid growth of Dry Strength Resin demand.Study of Paper-Strengthening Agent Based has been widely used in the production process of all kinds of paper and cardboard, in order to the dry strength of remarkable increase paper and cardboard, reduces high-quality raw material consumption, reduces production costs; Perhaps improve product specification, the more and more higher specification of quality constantly proposed to meet the user.
Dry Strength Resin commonly used has natural polymer such as starch and modifier (cationic starch, anionic starch, cross-linking starch etc.), synthetic polymer such as polyacrylamide, polyvinyl alcohol etc. and other water-soluble natural product type Dry Strength Resin (as guar gum and derivative thereof etc.).In most of the cases, only add such material of massfraction 0.1%-0.75% just can reach effectively dry potent fruit.
Current effect Dry Strength Resin preferably is polyacrylamide and multipolymer thereof, comprises anion-polyacrylamide, cationic-type polyacrylamide and amphiprotic polyacrylamide.Wherein amphiprotic polyacrylamide shows best effect.Polyacrylamide is from also dividing direct linkage type and branched chain type in view of structure.The polyacrylamide that the degree of branching is high has better effect.According to the literature, molecular weight is in the application performance preferably that has of 500,000 left and right.
The main flow of current synthesized high-performance Dry Strength Resin and the branched chain type amphiphilic polymers that trend is synthetic molecular weight and modest viscosity.This Dry Strength Resin can play the dry enhancement of good paper in the situation that do not add Tai-Ace S 150.The normal employing adds the method for linking agent to obtain the branched chain type Dry Strength Resin, but often has a common problem, is exactly reaction process control problem, and the viscosity of resulting polymers often there will be excessive or too small problem, controls the improper gelation that also often there will be.Because various monomer prices used are higher, the cost of synthesis type Dry Strength Resin is relatively high at present.Starch is carried out to graft modification and both can reduce the cost of product, can also obtain close with modified starch series Dry Strength Resin performance with existing polyacrylamide or better Dry Strength Resin by suitable composition and engineering.
Summary of the invention
The preparation method who the purpose of this invention is to provide a kind of Dry Strength Resin, the above-mentioned defect existed to overcome prior art.
The objective of the invention is to be achieved through the following technical solutions:
In reactor, add cationic starch and water to mix, be heated to 75-95 ℃ of gelatinization, form uniform liquid, add successively again water, acrylamide, cross-linkable monomer, chain-transfer agent, other functional monomers and photoinitiator, under oxygen-free environment, temperature is risen to 70-95 ℃, to reaction system irradiating ultraviolet light reaction 1.5-2 hour, start afterwards to take a sample at times and carry out viscosity test, viscosity stops irradiating ultraviolet light after reaching 4000-9000mP*s, add pH adjusting agent to regulate pH to 4-6, finally add free radical scavenger, obtain described Dry Strength Resin.
The weight ratio of above each component following (calculating with effective content 100%):
Wherein:
Described cationic starch, can select according to practical situation the product of different cationic degrees, to adapt to the demand of actual use;
Described acrylamide can add with solid form, and also used water solution form adds, and if with aqueous solution form, added, need carry out effective content calculating and guarantee its effective content, and should be according to the add-on of water in practical situation adjustment system.
Described cross-linkable monomer is one or more in di-vinyl monomers (as methylene-bisacrylamide etc.), trivinyl monomer (as N, N-diallyl acrylamide etc.) or the activated monomer of other tools (as N,N-DMAA etc.).The participation of cross-linkable monomer, can make polymkeric substance produce side chain at an easy rate.
Described other functional monomers can be one or more in some soft monomers (as Hydroxyethyl acrylate, Propylene glycol monoacrylate), hard monomer (as vinylbenzene, methyl methacrylate), hydrophobic monomer (as alkyl acrylate, alkyl methacrylate etc.).Various functional monomers are in order to adjust the performance of Dry Strength Resin in some special aspects.Soft monomer can improve the performance of Dry Strength Resin aspect the paper folding endurance, and hard monomer can be strengthened Dry Strength Resin in the performance of improving on the paper ring crush index, and hydrophobic monomer can improve the dispersiveness of Dry Strength Resin in water.
Described photoinitiator is benzophenone, benzophenone soluble derivative, st-yrax analog derivative, fluorescein and eosin etc.
Described chain-transfer agent can be for inorganic chain-transfer agent (as sodium bisulfite, Sodium Pyrosulfite and Sulfothiorine etc.), organic chain transfer agent (as positive Dodecyl Mercaptan, tert-dodecyl mercaptan, Thiovanic acid, mercaptoethanol, with other materials of sulfydryl, Virahol etc.) with one or more in allylic monomer.
Described free radical scavenger is the material (as sodium bisulfite, xitix etc.) that various water-soluble stoppers (as Resorcinol, benzoquinones, iron(ic) chloride, neutralized verdigris etc.) maybe can consume free radical.
Described pH adjusting agent determines as the case may be, when before the system pH regulator higher than 6 the time, pH adjusting agent is acids (example hydrochloric acid, sulfuric acid, acetic acid, phosphoric acid etc.); When before the system pH regulator lower than 4 the time, pH adjusting agent is bases (as NaOH, ammoniacal liquor etc.).
Described ultraviolet source is high voltage mercury lamp, and its wavelength is 100-1000nm, and its power is according to the size adjustment of reaction vessel.
The present invention adopts UV-irradiation photoinitiator initiated polymerization to prepare Dry Strength Resin: the cationic starch aqueous solution of take is basis, take acrylamide, cross-linkable monomer, chain-transfer agent and other functional monomers is the grafting raw material, under the existence of photoinitiator, in nitrogen atmosphere with the UV-irradiation Inducing Graft Polymerization, viscosity stops irradiating ultraviolet light after reaching target zone, finishes polyreaction.Due to light-initiated characteristics, free radical can produce in a short period of time, also can disappear in a short period of time, therefore the method is compared conventional synthetic method and is had simple to operate, viscosity is easy to control, the advantages such as gelation can be effectively prevented, all moderate Dry Strength Resins of molecular weight, the degree of branching and viscosity can be obtained.
By grafted polyacrylamide chain in cationic starch, make gained graftomer type Dry Strength Resin have the advantage of starch based Dry Strength Resin and polyacrylamide Dry Strength Resin concurrently, both also show synergy.In synthetic, introduce cross-linkable monomer, make grafted chain itself also have branched structure, this gives its unique performance.Moreover, by adjusting the ratio of soft or hard monomer, make Dry Strength Resin have suitable hard and soft property and adhesive property.The performances such as the above ring pressure that these make such Dry Strength Resin add after paper pulp can to improve into well paper, folding, anti-broken, anti-tensile, paper internal bond strength.In addition, the branched structure that this Dry Strength Resin has and suitable hydrophilic and hydrophobic matter, make it have less viscosity, in water, has good dispersiveness, can dilute at an easy rate, the convenient use.
The Dry Strength Resin synthetic by present method has the advantages that consumption is few, effective, cost is low.Can in the production of the multiple paper kinds such as boxboard, Corrugating Base Paper, enamelled paper, cop tube paper, speciality paper, use, play the effect that increases the paper dry strength, especially when with reclaimed waste paper, starching as paper making raw material, effect is more remarkable.Such Dry Strength Resin can have the dry reinforced effects of outstanding paper in the situation that do not add Tai-Ace S 150.
Embodiment
In embodiment, the consumption of component is weight part.
Embodiment 1
In reactor, add water 350g, under stirring, add the 35g cationic starch, be heated to 75 ℃ and carried out gelatinization 2 hours, then add successively acrylamide 101g, DMAA 1g, ethyl thioglycolate 0.6g, Propylene glycol monoacrylate 3g, ethyl propenoate 1.5g and benzophenone 0.6g stir, add 55g water and rinse charging opening, reactor is vacuumized to logical nitrogen 2-3 time repeatedly, then maintain logical nitrogen, temperature of reaction kettle is risen to 85 ℃, to the reaction system irradiating ultraviolet light, in the situation of basic maintenance constant temperature, reaction is 1.5 hours, start afterwards to carry out viscosity test every sampling in 20 minutes, viscosity stops irradiating ultraviolet light after reaching 7000mP*s, add sulfuric acid (15%) 0.5g to regulate pH to 4-6, finally add Resorcinol 0.01g, add water and regulate solid content to 20 ± 1%, be the finished product.
Embodiment 2
In reactor, add water 350g, under stirring, add the 58g cationic starch, be heated to 85 ℃ and carried out gelatinization 1 hour, then add successively acrylamide 60g, methylene-bisacrylamide 0.08g, mercaptoethanol 0.8g, Propylene glycol monoacrylate 15g, vinylbenzene 5g and benzophenone 0.5g stir, with 50g water, rinse charging opening, reactor is vacuumized to logical nitrogen 2-3 time repeatedly, then maintain logical nitrogen, temperature of reaction kettle is risen to 75 ℃, to the reaction system irradiating ultraviolet light, in the situation of basic maintenance constant temperature, reaction is 2 hours, start afterwards to carry out viscosity test every sampling in 20 minutes, viscosity stops irradiating ultraviolet light after reaching 5000mP*s, add sulfuric acid (15%) 0.5g to regulate pH to 4-6, finally add sodium bisulfite 2g, add water and regulate solid content to 20 ± 1%, be the finished product.
Embodiment 3
In reactor, add water 450g, under stirring, add the 40g cationic starch, be heated to 95 ℃ and carried out gelatinization 0.5 hour, then add successively acrylamide 52g, methylene-bisacrylamide 0.03g, sodium allyl sulfonate 0.2g, methyl methacrylate 4g, Propylene glycol monoacrylate 1g, ethyl propenoate 1g and benzophenone 0.5g stir, with 70g water, rinse charging opening, reactor is vacuumized to logical nitrogen 2-3 time repeatedly, then maintain logical nitrogen, temperature of reaction kettle is risen to 85 ℃, to the reaction system irradiating ultraviolet light, in the situation of basic maintenance constant temperature, reaction is 1.5 hours, start afterwards to carry out viscosity test every sampling in 20 minutes, viscosity stops irradiating ultraviolet light after reaching 6500mP*s, regulate pH to 4-6, finally add para benzoquinone 0.01g, add water and regulate solid content to 15 ± 1%, be the finished product.
Embodiment 4
In reactor, add water 400g, under stirring, add the 110g cationic starch, be heated to 95 ℃ and carried out gelatinization 1 hour, then add successively acrylamide 55g, DMAA 1g, sodium allyl sulfonate 0.6g, Dodecyl Mercaptan 0.002g, Propylene glycol monoacrylate 4g, vinylbenzene 2g and benzoin methyl ether 0.5g stir, add 20g water and rinse charging opening, reactor is vacuumized to logical nitrogen 2-3 time repeatedly, then maintain logical nitrogen, temperature of reaction kettle is risen to 82 ℃, to the reaction system irradiating ultraviolet light, in the situation of basic maintenance constant temperature, reaction is 2 hours, start afterwards to carry out viscosity test every sampling in 20 minutes, viscosity stops irradiating ultraviolet light after reaching 8500mP*s, regulate pH to 4-6, finally add Dichlorodiphenyl Acetate copper 0.01g, add water and regulate solid content to 30 ± 1%, be the finished product.
Comparative example 1
In reactor, add successively water 405g, acrylamide 120g, MethacryloyloxyethylTrimethyl Trimethyl Ammonium Chloride 16g, methylene-bisacrylamide 0.08g, mercaptoethanol 1g, Propylene glycol monoacrylate 4g, ethyl propenoate 2g and benzophenone 1g stir, reactor is vacuumized to logical nitrogen 2-3 time repeatedly, then maintain logical nitrogen, temperature of reaction kettle is risen to 85 ℃, to the reaction system irradiating ultraviolet light, in the situation of basic maintenance constant temperature, reaction is 1.5 hours, start afterwards to carry out viscosity test every sampling in 20 minutes, viscosity stops irradiating ultraviolet light after reaching 4500mP*s, add liquid caustic soda (32%) 1.5g to regulate pH to 4-6, finally add Resorcinol 0.02g, add water and regulate solid content to 20 ± 1%.
Comparative example 2
In reactor, add successively water 550g, acrylamide 83g, MethacryloyloxyethylTrimethyl Trimethyl Ammonium Chloride 9g, DMAA 0.8g, sodium allyl sulfonate 0.2g stirs, logical nitrogen drove oxygen 60 minutes, be warmed up to 60 ℃, add ammonium persulphate 0.5g(to be dissolved in 20g water), temperature of reaction kettle is risen to 82 ℃, react after 1 hour and start sampling detection viscosity.Viscosity adds the stopper stopped reaction after reaching 3500mPa*s.Regulate pH to 4-6, adding water move to solid content is 15 ± 1%.
Application Example
Adopt the reclaimed waste paper case to pull an oar as raw material, beating degree adds Dry Strength Resin to stir 5 minutes after reaching 35 ° of SR, after being shaped, adopts by semi-automatic sheet-former the squeezing of standard page squeezing machine, natural air drying, then detect the index such as tensile strength, ring crush intensity, bursting strength, folding endurance, internal bond strength of paper.The Dry Strength Resin add-on is 4.5-7.5 ‰ (dry/oven dry stock).Table 2 has provided the application data of the prepared Dry Strength Resin of aforesaid method.
Table 1. adds the handsheet intensity index (dry/oven dry stock) of Dry Strength Resin
As can be known by above-described embodiment, Comparative Examples and application examples, the synthetic Dry Strength Resin of method therefor of the present invention has good application performance, on effect, compares and approaches or certain advantage arranged with the cationic Dry Strength Resin of polyacrylamide.And wherein part material is cheap cationic starch, can be significantly reduced to this.
Claims (9)
1. a uv-light polymerization prepares the method for Dry Strength Resin, it is characterized in that, comprise the steps: cationic starch and water are mixed, the heating gelatinization, add successively again water, acrylamide, cross-linkable monomer, chain-transfer agent, other functional monomers and photoinitiator, under oxygen-free environment, temperature is risen to 70-95 ℃, to reaction system irradiating ultraviolet light reaction 1.5-2 hour, viscosity test is carried out in sampling at set intervals afterwards, viscosity stops irradiating ultraviolet light after reaching 4000-9000mP*s, add pH adjusting agent to regulate pH to 4-6, and add free radical scavenger, obtain described Dry Strength Resin.
2. method according to claim 1, is characterized in that, the parts by weight of each component are as follows:
3. method according to claim 2, is characterized in that, described cross-linkable monomer is selected from more than one in di-vinyl monomers, trivinyl monomer.
4. method according to claim 3, is characterized in that, described cross-linkable monomer is methylene-bisacrylamide, N, more than one in N-diallyl acrylamide, N,N-DMAA.
5. method according to claim 2, is characterized in that, described other functional monomers are selected from more than one in soft monomer, hard monomer, hydrophobic monomer.
6. method according to claim 5, is characterized in that, described other functional monomers are more than one in Hydroxyethyl acrylate, Propylene glycol monoacrylate, vinylbenzene, methyl methacrylate, alkyl acrylate, alkyl methacrylate.
7. method according to claim 2, is characterized in that, described photoinitiator is more than one of benzophenone, benzophenone soluble derivative, st-yrax analog derivative, fluorescein and eosin.
8. method according to claim 2, is characterized in that, described chain-transfer agent is more than one of sodium bisulfite, Sodium Pyrosulfite and Sulfothiorine etc., positive Dodecyl Mercaptan, tert-dodecyl mercaptan, Thiovanic acid, mercaptoethanol, Virahol.
9. method according to claim 2, is characterized in that, described free radical scavenger is Resorcinol, benzoquinones, iron(ic) chloride, neutralized verdigris, sodium bisulfite, xitix.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN107287976A (en) * | 2017-06-27 | 2017-10-24 | 安徽比伦生活用纸有限公司 | A kind of preparation method of high-quality napkin paper |
| CN109535319A (en) * | 2018-11-07 | 2019-03-29 | 济宁明升新材料有限公司 | A kind of environmentally friendly drying strengthening agent and preparation method thereof |
| CN109535320A (en) * | 2018-11-07 | 2019-03-29 | 济宁明升新材料有限公司 | A kind of preparation method of the modified drying strengthening agent of the polysaccharose substance that performance is controllable |
| CN109736134A (en) * | 2019-03-05 | 2019-05-10 | 山东天阳纸业有限公司 | A kind of machine glazing thermosensitive body paper manufacturing method |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107287976A (en) * | 2017-06-27 | 2017-10-24 | 安徽比伦生活用纸有限公司 | A kind of preparation method of high-quality napkin paper |
| CN109535319A (en) * | 2018-11-07 | 2019-03-29 | 济宁明升新材料有限公司 | A kind of environmentally friendly drying strengthening agent and preparation method thereof |
| CN109535320A (en) * | 2018-11-07 | 2019-03-29 | 济宁明升新材料有限公司 | A kind of preparation method of the modified drying strengthening agent of the polysaccharose substance that performance is controllable |
| CN109736134A (en) * | 2019-03-05 | 2019-05-10 | 山东天阳纸业有限公司 | A kind of machine glazing thermosensitive body paper manufacturing method |
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Address after: 200233 Shanghai, Tianlin Road, No. 388, building 701, room 1, Applicant after: Shanghai Dongsheng new material Co., Ltd. Applicant after: Dssun New Material (Shandong) Co., Ltd. Address before: 200233 Shanghai, Tianlin Road, No. 388, building 701, room 1, Applicant before: Shanghai Dongsheng new material Co., Ltd. Applicant before: Yanzhou Dongsheng Fine Chemical Co., Ltd. |
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