CN116791398A - CS-PL-FEC/taro starch phosphate multifunctional protective solution for paper protection - Google Patents
CS-PL-FEC/taro starch phosphate multifunctional protective solution for paper protection Download PDFInfo
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- CN116791398A CN116791398A CN202310977377.1A CN202310977377A CN116791398A CN 116791398 A CN116791398 A CN 116791398A CN 202310977377 A CN202310977377 A CN 202310977377A CN 116791398 A CN116791398 A CN 116791398A
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- 244000205754 Colocasia esculenta Species 0.000 title claims abstract description 47
- 235000006481 Colocasia esculenta Nutrition 0.000 title claims abstract description 47
- 229920002472 Starch Polymers 0.000 title claims abstract description 47
- 235000019698 starch Nutrition 0.000 title claims abstract description 47
- 239000008107 starch Substances 0.000 title claims abstract description 47
- 229910019142 PO4 Inorganic materials 0.000 title claims abstract description 46
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 title claims abstract description 46
- 239000010452 phosphate Substances 0.000 title claims abstract description 46
- 230000001681 protective effect Effects 0.000 title claims abstract description 44
- 108010039918 Polylysine Proteins 0.000 claims abstract description 73
- 229920001661 Chitosan Polymers 0.000 claims abstract description 64
- 239000007788 liquid Substances 0.000 claims abstract description 38
- KXDHJXZQYSOELW-UHFFFAOYSA-M Carbamate Chemical compound NC([O-])=O KXDHJXZQYSOELW-UHFFFAOYSA-M 0.000 claims abstract description 28
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 claims description 66
- ZMANZCXQSJIPKH-UHFFFAOYSA-N Triethylamine Chemical compound CCN(CC)CC ZMANZCXQSJIPKH-UHFFFAOYSA-N 0.000 claims description 60
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 38
- SBLRHMKNNHXPHG-UHFFFAOYSA-N 4-fluoro-1,3-dioxolan-2-one Chemical compound FC1COC(=O)O1 SBLRHMKNNHXPHG-UHFFFAOYSA-N 0.000 claims description 32
- NQTADLQHYWFPDB-UHFFFAOYSA-N N-Hydroxysuccinimide Chemical compound ON1C(=O)CCC1=O NQTADLQHYWFPDB-UHFFFAOYSA-N 0.000 claims description 30
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 30
- 230000001105 regulatory effect Effects 0.000 claims description 25
- 239000003292 glue Substances 0.000 claims description 24
- 238000003756 stirring Methods 0.000 claims description 23
- 239000000047 product Substances 0.000 claims description 19
- 238000006243 chemical reaction Methods 0.000 claims description 18
- 239000003054 catalyst Substances 0.000 claims description 16
- 238000000502 dialysis Methods 0.000 claims description 16
- 238000001704 evaporation Methods 0.000 claims description 16
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 16
- FPQQSJJWHUJYPU-UHFFFAOYSA-N 3-(dimethylamino)propyliminomethylidene-ethylazanium;chloride Chemical compound Cl.CCN=C=NCCCN(C)C FPQQSJJWHUJYPU-UHFFFAOYSA-N 0.000 claims description 12
- 239000003795 chemical substances by application Substances 0.000 claims description 10
- 239000007822 coupling agent Substances 0.000 claims description 10
- 239000012153 distilled water Substances 0.000 claims description 10
- 238000001035 drying Methods 0.000 claims description 9
- 239000007787 solid Substances 0.000 claims description 9
- 239000006227 byproduct Substances 0.000 claims description 8
- 238000010438 heat treatment Methods 0.000 claims description 8
- 238000011068 loading method Methods 0.000 claims description 8
- 238000003760 magnetic stirring Methods 0.000 claims description 8
- 238000002156 mixing Methods 0.000 claims description 8
- 230000001376 precipitating effect Effects 0.000 claims description 8
- 239000002904 solvent Substances 0.000 claims description 8
- 238000005303 weighing Methods 0.000 claims description 8
- 239000002253 acid Substances 0.000 claims description 4
- 239000003513 alkali Substances 0.000 claims description 2
- 230000006196 deacetylation Effects 0.000 claims description 2
- 238000003381 deacetylation reaction Methods 0.000 claims description 2
- 239000000203 mixture Substances 0.000 claims description 2
- 230000000844 anti-bacterial effect Effects 0.000 abstract description 7
- 230000015556 catabolic process Effects 0.000 abstract description 4
- 238000006731 degradation reaction Methods 0.000 abstract description 4
- 230000002209 hydrophobic effect Effects 0.000 abstract description 4
- 230000004048 modification Effects 0.000 abstract description 4
- 238000012986 modification Methods 0.000 abstract description 4
- 230000003014 reinforcing effect Effects 0.000 abstract description 3
- 229920002521 macromolecule Polymers 0.000 abstract description 2
- 239000002994 raw material Substances 0.000 abstract description 2
- 230000008929 regeneration Effects 0.000 abstract description 2
- 238000011069 regeneration method Methods 0.000 abstract description 2
- 230000002787 reinforcement Effects 0.000 abstract description 2
- 241000209094 Oryza Species 0.000 description 4
- 235000007164 Oryza sativa Nutrition 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 235000009566 rice Nutrition 0.000 description 4
- 230000002378 acidificating effect Effects 0.000 description 3
- 125000003277 amino group Chemical group 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 241000894006 Bacteria Species 0.000 description 2
- KXDHJXZQYSOELW-UHFFFAOYSA-N Carbamic acid Chemical group NC(O)=O KXDHJXZQYSOELW-UHFFFAOYSA-N 0.000 description 2
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 2
- 239000013543 active substance Substances 0.000 description 2
- 230000010933 acylation Effects 0.000 description 2
- 238000005917 acylation reaction Methods 0.000 description 2
- 230000029936 alkylation Effects 0.000 description 2
- 238000005804 alkylation reaction Methods 0.000 description 2
- 230000009435 amidation Effects 0.000 description 2
- 238000007112 amidation reaction Methods 0.000 description 2
- VILAVOFMIJHSJA-UHFFFAOYSA-N dicarbon monoxide Chemical group [C]=C=O VILAVOFMIJHSJA-UHFFFAOYSA-N 0.000 description 2
- 239000000835 fiber Substances 0.000 description 2
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 244000005700 microbiome Species 0.000 description 2
- 238000000967 suction filtration Methods 0.000 description 2
- 230000032683 aging Effects 0.000 description 1
- 238000007605 air drying Methods 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 229910021386 carbon form Inorganic materials 0.000 description 1
- 239000000969 carrier Substances 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000008367 deionised water Substances 0.000 description 1
- 229910021641 deionized water Inorganic materials 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- BNIILDVGGAEEIG-UHFFFAOYSA-L disodium hydrogen phosphate Chemical compound [Na+].[Na+].OP([O-])([O-])=O BNIILDVGGAEEIG-UHFFFAOYSA-L 0.000 description 1
- 125000001153 fluoro group Chemical group F* 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 230000002427 irreversible effect Effects 0.000 description 1
- 239000012263 liquid product Substances 0.000 description 1
- 125000003588 lysine group Chemical group [H]N([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])(N([H])[H])C(*)=O 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 230000000813 microbial effect Effects 0.000 description 1
- 239000000178 monomer Substances 0.000 description 1
- 229910000403 monosodium phosphate Inorganic materials 0.000 description 1
- 235000019799 monosodium phosphate Nutrition 0.000 description 1
- 230000000269 nucleophilic effect Effects 0.000 description 1
- 238000010525 oxidative degradation reaction Methods 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 125000002924 primary amino group Chemical group [H]N([H])* 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 230000008439 repair process Effects 0.000 description 1
- 238000007142 ring opening reaction Methods 0.000 description 1
- AJPJDKMHJJGVTQ-UHFFFAOYSA-M sodium dihydrogen phosphate Chemical compound [Na+].OP(O)([O-])=O AJPJDKMHJJGVTQ-UHFFFAOYSA-M 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- JOYRKODLDBILNP-UHFFFAOYSA-N urethane group Chemical group NC(=O)OCC JOYRKODLDBILNP-UHFFFAOYSA-N 0.000 description 1
- 238000004383 yellowing Methods 0.000 description 1
Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H19/00—Coated paper; Coating material
- D21H19/36—Coatings with pigments
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H19/00—Coated paper; Coating material
- D21H19/36—Coatings with pigments
- D21H19/44—Coatings with pigments characterised by the other ingredients, e.g. the binder or dispersing agent
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
- D21H21/14—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties characterised by function or properties in or on the paper
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H25/00—After-treatment of paper not provided for in groups D21H17/00 - D21H23/00
- D21H25/18—After-treatment of paper not provided for in groups D21H17/00 - D21H23/00 of old paper as in books, documents, e.g. restoring
Landscapes
- Polysaccharides And Polysaccharide Derivatives (AREA)
Abstract
The invention relates to a macromolecule, in particular to CS-PL-FEC/taro starch phosphate multifunctional protective solution for paper protection, which comprises the following components in parts by weight: 48-67 parts of epsilon-polylysine modified chitosan carbamate (CS-PL-FEC) and 27-34 parts of taro starch phosphate; the invention is scientific and reasonable, has rich raw materials, is green and environment-friendly, has no pollution, is easy to produce and prepare, has the advantages of biocompatibility, easy degradation, regeneration, easy modification and the like, integrates reinforcement, deacidification, hydrophobicity, mildew resistance and bacteriostasis, and has better biocompatibility with paper, so that the prepared multifunctional protective liquid has excellent physical and mechanical properties, and plays a role in reinforcing the paper; the paper is reinforced, and meanwhile, certain hydrophobic performance is also endowed to the paper; the antibacterial effect on paper is achieved, and the aim of slow-release deacidification is achieved for paper protection; the protective liquid is coated on paper, so that not only is the mechanical property of the paper greatly improved, but also the glossiness and whiteness are basically unchanged, and the principle of ' repairing old as old ' and keeping original appearance ' is met.
Description
Technical Field
The invention relates to a macromolecule, in particular to CS-PL-FEC/taro starch phosphate multifunctional protective solution for paper protection.
Background
The paper cultural relics are used as important carriers for cultural relic propagation, and have extremely high value. Due to the influence of internal and external factors, acid-base degradation, oxidative degradation and microbial degradation of the paper fiber can occur to different degrees, so that the internal structure of the paper is damaged, and irreversible damage is caused to paper cultural relics. Paper cultural relics are facing a variety of problems, particularly: ageing, yellowing, mildew, adhesion, wrinkling, breakage and the like, so that cultural relics workers face the difficult task of repairing damaged papery cultural relics, and at present, although protective liquid for repairing papery cultural relics is available, most of the protective liquid has unsatisfactory use effects, poor reinforcing, hydrophobic, deacidifying and antibacterial effects, is not easy to degrade and is not friendly to the environment, and the novel environment-friendly green protective liquid has the technical problems that the novel environment-friendly green protective liquid has good use effects and is necessary to solve.
Disclosure of Invention
Aiming at the situation, in order to overcome the defects of the prior art, the invention aims to provide the CS-PL-FEC/taro starch phosphate multifunctional protective solution for paper protection, which can effectively solve the problem that the existing protective solution can not be used for collecting paper to drain water, oleophobic, deacidify, strengthen, inhibit bacteria and degrade at the same time.
The technical scheme is that CS-PL-FEC/taro starch phosphate multifunctional protective solution for paper protection comprises the following components in parts by weight: 48-67 parts of epsilon-polylysine modified chitosan carbamate (CS-PL-FEC) and 27-34 parts of taro starch phosphate;
the epsilon-polylysine modified chitosan-based carbamate (CS-PL-FEC) is prepared by the following steps:
sequentially adding distilled water and epsilon-polylysine (epsilon-PL) into a three-neck flask, sequentially adding N-hydroxysuccinimide coupling agent (NHS) and 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride condensing agent (EDC. HCl) after 30min, regulating the pH to 4-6 by using 0.6mol/L hydrochloric acid solution to dissolve solute, regulating the temperature to 30 ℃, reacting for 24 h, regulating the pH to 7-9 by using 0.5mol/L NaOH solution after the reaction is finished, precipitating the product, loading the product into a dialysis bag with the molecular weight cutoff of 8000, dialyzing for one week, removing unreacted epsilon-PL, NHS, EDC. HCl and byproducts, rotationally evaporating the cutoff liquid, and transferring the solid into a freeze dryer for drying to obtain epsilon-polylysine modified chitosan (CS-PL);
weighing CS-PL, placing in 1wt% dilute acetic acid, magnetically stirring at 30deg.C and 1600r/min for 3h to dissolve CS-PL, heating to 60deg.C, dropwise adding triethylamine as catalyst, mixing well, dropwise adding fluoroethylene carbonate (FEC), stirring for 8h, stopping reaction to obtain transparent liquid, placing transparent liquid into dialysis bag with molecular weight cut-off of 3000-5000, removing unreacted FEC, solvent acetic acid and triethylamine as catalyst, rotary evaporating the cut-off components, concentrating to obtain epsilon-polylysine modified chitosan-based carbamate (CS-PL-FEC) glue solution with solute mass fraction of 1-10wt%;
adding CS-PL-FEC glue solution into a three-neck flask, adding taro starch phosphate into the glue solution CS-PL-FEC under the conditions of magnetic stirring at room temperature and 800r/min, and uniformly stirring to obtain CS-PL-FEC/taro starch phosphate multifunctional protective solution;
the weight volume ratio of the Chitosan (CS), distilled water, epsilon-polylysine (epsilon-PL), N-hydroxysuccinimide coupling agent (NHS), 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride condensing agent (EDC & HCl), epsilon-polylysine modified chitosan (CS-PL), dilute acetic acid, triethylamine, fluoroethylene carbonate (FEC), epsilon-polylysine modified chitosan carbamate (CS-PL-FEC) and taro starch phosphate is as follows:
1:100:0.6587-0.9867:0.11895:0.1975-0.5923:1:100:0.02-0.08：0.7857：63-78:18-28。
the invention is scientific and reasonable, has rich raw materials, is green and environment-friendly, has no pollution, is easy to produce and prepare, has the advantages of biocompatibility, easy degradation, regeneration, easy modification and the like, integrates reinforcement, deacidification, hydrophobicity, mildew resistance and bacteriostasis, and the prepared multifunctional protective liquid has better biocompatibility with paper, and can form a stable seven-membered ring structure in molecules due to the urethane group in the formed product, thereby endowing the protective liquid with excellent physical and mechanical properties and playing a role in reinforcing the paper; the multifunctional protective liquid contains C-F bonds, and certain hydrophobic property is given to the paper while the paper is reinforced; epsilon-polylysine is a homotype monomer polymer containing 25-30 lysine residues, natural antibacterial active substances play a role in inhibiting bacteria on paper, and C-2 and C-6 positions on chitosan molecules respectively contain a large number of active amino groups and hydroxyl groups, so that chemical reactions such as alkylation, acylation and the like can be carried out under certain conditions, and the epsilon-polylysine carries out amidation modification on CS, contains a large number of alkaline amino groups in the molecules, can neutralize acidic substances in the paper, and plays a role in slow-release deacidification on paper protection; the protective liquid with the mass concentration of 0.5 percent is coated on paper, so that the mechanical property of the paper is greatly improved, the glossiness and whiteness are basically unchanged, and the principle of 'repairing old and keeping original appearance' is met.
Drawings
FIGS. 1 and 2 are diagrams showing the synthesis mechanism of epsilon-polylysine modified chitosan-based carbamate (CS-PL-FEC) of the present invention.
Detailed Description
The following describes the embodiments of the present invention in detail with reference to examples and specific cases. It should be understood that these examples are illustrative of the present invention and are not intended to limit the scope of the present invention.
Example 1
The CS-PL-FEC/taro starch phosphate multifunctional protective solution for paper protection comprises the following components in parts by weight: 67 parts of epsilon-polylysine modified chitosan carbamate (CS-PL-FEC) and 34 parts of taro starch phosphate;
the epsilon-polylysine modified chitosan-based carbamate (CS-PL-FEC) is prepared by the following steps:
taking 1g (CS) of chitosan into a three-neck flask, sequentially adding 100g of distilled water and 0.9867g of epsilon-polylysine (epsilon-PL), after 30min, sequentially adding 0.11895g of N-hydroxysuccinimide coupling agent (NHS) and 0.5923g of 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride condensing agent (EDC. HCl), regulating the pH to 4-6 by using 0.6mol/L hydrochloric acid solution to fully dissolve the solute, regulating the temperature to 30 ℃, reacting for 24 hours, regulating the pH to 7-9 by using 0.5mol/L NaOH solution after the reaction is finished, precipitating the product, loading the product into a dialysis bag with a cut-off molecular weight of 8000, dialyzing for one week, removing unreacted epsilon-PL, NHS, EDC. HCl and byproducts, rotationally evaporating the cut-off solution, transferring the solid into a freeze dryer, and drying to obtain epsilon-polylysine modified chitosan (CS-PL);
weighing 1gCS-PL, placing in 100ml of 1wt% dilute acetic acid, magnetically stirring at 30deg.C and 1600r/min for 3h to dissolve CS-PL, heating to 60deg.C, dropwise adding 0.04g of catalyst triethylamine, mixing, slowly dropwise adding 0.7857g of fluoroethylene carbonate (FEC), stirring for 8h, stopping reaction to obtain transparent liquid, placing the transparent liquid into dialysis bag with molecular weight cut-off of 3000-5000, removing unreacted FEC, solvent acetic acid and catalyst triethylamine, rotationally evaporating the cut-off components, and concentrating to obtain epsilon-polylysine modified chitosan-based carbamate (CS-PL-FEC) glue solution with solute mass fraction of 1wt% -10wt%;
71g of CS-PL-FEC glue solution is weighed and added into a three-neck flask, 28g of taro starch phosphate is added into the glue solution CS-PL-FEC under the condition of magnetic stirring at room temperature and 800r/min, and the stirring is uniform, so that the CS-PL-FEC/taro starch phosphate multifunctional protective solution is obtained.
Example 2
The CS-PL-FEC/taro starch phosphate multifunctional protective solution for paper protection comprises the following components in parts by weight: 67 parts of epsilon-polylysine modified chitosan carbamate (CS-PL-FEC) and 27 parts of taro starch phosphate;
the epsilon-polylysine modified chitosan-based carbamate (CS-PL-FEC) is prepared by the following steps:
taking 1g (CS) of chitosan into a three-neck flask, sequentially adding 100g of distilled water and 0.6587g of epsilon-polylysine (epsilon-PL), after 30min, sequentially adding 0.11895g of N-hydroxysuccinimide coupling agent (NHS) and 0.1975g of 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride condensing agent (EDC. HCl), regulating the pH to 4-6 by using 0.6mol/L hydrochloric acid solution to fully dissolve the solute, regulating the temperature to 30 ℃, reacting for 24 h, regulating the pH to 7-9 by using 0.5mol/L NaOH solution after the reaction is finished, precipitating the product, loading the product into a dialysis bag with a cut-off molecular weight of 8000, dialyzing for one week, removing unreacted epsilon-PL, NHS, EDC. HCl and byproducts, rotationally evaporating the cut-off solution, transferring the solid into a freeze dryer, and drying to obtain epsilon-polylysine modified chitosan (CS-PL);
weighing 1gCS-PL, placing in 100ml of 1wt% dilute acetic acid, magnetically stirring at 30deg.C and 1600r/min for 3h to dissolve CS-PL, heating to 60deg.C, dropwise adding 0.06g of catalyst triethylamine, mixing, slowly dropwise adding 0.7857g of fluoroethylene carbonate (FEC), stirring for 8h, stopping reaction to obtain transparent liquid, placing the transparent liquid into dialysis bag with molecular weight cut-off of 3000-5000, removing unreacted FEC, solvent acetic acid and catalyst triethylamine, rotationally evaporating the cut-off components, and concentrating to obtain epsilon-polylysine modified chitosan-based carbamate (CS-PL-FEC) glue solution with solute mass fraction of 1wt% -10wt%;
63g of CS-PL-FEC glue solution is weighed and added into a three-neck flask, 22g of taro starch phosphate is added into the glue solution CS-PL-FEC under the condition of magnetic stirring at room temperature and 800r/min, and the mixture is stirred uniformly to obtain the CS-PL-FEC/taro starch phosphate multifunctional protective solution.
Example 3
The CS-PL-FEC/taro starch phosphate multifunctional protective solution for paper protection comprises the following components in parts by weight: 58 parts of epsilon-polylysine modified chitosan carbamate (CS-PL-FEC) and 31 parts of taro starch phosphate;
the epsilon-polylysine modified chitosan-based carbamate (CS-PL-FEC) is prepared by the following steps:
taking 1g (CS) of chitosan into a three-neck flask, sequentially adding 100g of distilled water and 0.6587g of epsilon-polylysine (epsilon-PL), after 30min, sequentially adding 0.11895g of N-hydroxysuccinimide coupling agent (NHS) and 0.5923g of 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride condensing agent (EDC. HCl), regulating the pH to 4-6 by using 0.6mol/L hydrochloric acid solution to fully dissolve the solute, regulating the temperature to 30 ℃, reacting for 24 hours, regulating the pH to 7-9 by using 0.5mol/L NaOH solution after the reaction is finished, precipitating the product, loading the product into a dialysis bag with a cut-off molecular weight of 8000, dialyzing for one week, removing unreacted epsilon-PL, NHS, EDC. HCl and byproducts, rotationally evaporating the cut-off solution, transferring the solid into a freeze dryer, and drying to obtain epsilon-polylysine modified chitosan (CS-PL);
weighing 1gCS-PL, placing in 100ml of 1wt% dilute acetic acid, magnetically stirring at 30deg.C and 1600r/min for 3h to dissolve CS-PL, heating to 60deg.C, dropwise adding 0.08g of catalyst triethylamine, mixing, slowly dropwise adding 0.7857g of fluoroethylene carbonate (FEC), stirring for 8h, stopping reaction to obtain transparent liquid, placing the transparent liquid into dialysis bag with molecular weight cut-off of 3000-5000, removing unreacted FEC, solvent acetic acid and catalyst triethylamine, rotationally evaporating the cut-off components, and concentrating to obtain epsilon-polylysine modified chitosan-based carbamate (CS-PL-FEC) glue solution with solute mass fraction of 1wt% -10wt%;
78g of CS-PL-FEC glue solution is weighed and added into a three-neck flask, 20g of taro starch phosphate is added into the glue solution CS-PL-FEC under the condition of magnetic stirring at room temperature and 800r/min, and the stirring is uniform, so that the CS-PL-FEC/taro starch phosphate multifunctional protective solution is obtained.
The deacetylation degree of the chitosan is more than or equal to 95 percent, and the viscosity is 100-200 mPa.s;
the epsilon-polylysine has a purity of 50%;
the purity of the fluoroethylene carbonate is 98%;
the purity of the triethylamine is 99.7%;
the taro starch phosphate was prepared in laboratory (ds=0.03);
the alkali solution is sodium hydroxide solution with the concentration of 0.5 mol/L;
the acid solution is hydrochloric acid solution with the concentration of 0.6 mol/L;
the purity of the 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride is 98.5 percent;
the purity of the N-hydroxysuccinimide is 98%;
the dilute acetic acid is 1wt% acetic acid solution.
The taro starch phosphate is prepared by the following steps:
3g of sodium dihydrogen phosphate and 6g of disodium hydrogen phosphate are dissolved in 100ML of water, the pH value is regulated to be in the range of 5-7, 45g of taro starch is added, stirring is carried out for 30 minutes, standing and suction filtration are carried out, drying is carried out at 40 ℃ until the water content is lower than 10%, then the solution is placed in a constant temperature box at 150 ℃ for 4 hours, the reaction time is 4 hours, the sample is washed for 4-5 times by ethanol solution with the mass fraction of 50%, suction filtration and air drying are carried out, and the taro starch phosphate is obtained.
The weight percentages refer to solids in g and liquids in ml.
The CS-PL-FEC/taro starch phosphate multifunctional protective solution for paper protection prepared by the invention not only can enhance the physical and mechanical properties of paper such as tensile strength, folding times, tearing degree and the like, but also can keep the glossiness and whiteness of the paper unchanged basically, and accords with the principle of 'repairing and old' paper cultural relics.
The C-2 and C-6 positions of chitosan molecule contain a large amount of active amino and hydroxyl, respectively, and can generate chemical reactions such as alkylation, acylation and the like under certain conditions. The active-NH 2 in CS molecule carries out nucleophilic attack on carbonyl carbon atom of FEC, which leads to ring opening of the carbonyl carbon atom and forms chitosan derivative containing carbamate structure. The carbamate groups can form hydrogen bonds in molecules, so that the bonding force among paper fibers is improved, the mechanical properties of paper are further improved, and the paper is reinforced; FEC contains C-F bond, F atom has lower surface free energy, can migrate on the surface of the protective liquid, and can reduce specific surface energy of the protective liquid, thereby improving the hydrophobicity of the surface of the coated paper; the chitosan and epsilon-polylysine contain-NH 2 in the molecules, so that acidic substances in the paper can be neutralized, the alkalinity of the paper can be further improved, and the deacidification effect on the paper can be realized; epsilon-polylysine is a natural antibacterial active substance, the hydrophobicity of the surface of the coated paper is enhanced, the water source on which microorganisms depend to survive is cut off, the growth and propagation of the microorganisms are not facilitated, the antibacterial effect on the paper is achieved, and the multifunctional protective liquid for protecting the paper is provided.
When the invention is specifically used, modern calligraphy rice paper is used as a simulated paper pattern, the multifunctional protective liquid is sprayed on the surface of paper (210 mm multiplied by 297 mm) cut according to the standard for 5-10min, and the paper is naturally dried at room temperature. In order to verify the use effect of the invention, the product of the embodiment of the invention is used for treating the rice paper by the method, and the tensile strength, the folding endurance, the tearing strength, the glossiness and the whiteness of the rice paper before and after the treatment are tested. Deionized water is used as reference liquid, an OCA25 type contact angle measuring instrument is used for measuring the contact angle of water drops on the surface of paper, and the hydrophobicity of the paper sample is analyzed. Meanwhile, the product of the embodiment of the invention is used for carrying out antibacterial and mildew-proof measurement on rice paper, and the result is shown in table 1. Wherein, the tensile strength test of the paper is measured according to national standard GB/T12914-2008; the paper folding endurance is measured according to national standard GB/T457-2008; the paper tear degree is measured according to national standard GB/455-2002; the glossiness of the paper is measured according to national standard GB/T8941-2013; the whiteness of the paper is measured according to national standard GB/T7974-2002 in China.
The comparison of the performance index results of the paper treated by the multifunctional protective liquid prepared by the methods of examples 1, 2 and 3 is shown in Table 1:
table 1:
the invention adopts the chitosan with abundant resources as the matrix, and has the advantages of wide sources, simple preparation, scientific and reasonable formula, low production cost and no pollution. The prepared multifunctional protective liquid can strengthen paper and simultaneously endow the paper with certain mildew-proof and antibacterial properties; the multifunctional protective liquid product contains C-F bonds, so that the paper has certain hydrophobic property; the epsilon-polylysine carries out amidation modification on CS, increases the number of amino groups in molecules, can combine acid molecules when existing in weak acid solution, can neutralize acidic substances in paper, further improves the alkalinity of the paper, and plays a role in deacidifying the paper. The multifunctional protective liquid prepared by the invention has better biocompatibility with paper, can effectively enhance the mechanical strength of the paper, has insignificant change of whiteness and glossiness, can remove the protective film under the condition of no damage or little damage, accords with the principle of 'old repair and original appearance maintenance', and is innovation on paper object protective liquid.
Claims (5)
1. A CS-PL-FEC/taro starch phosphate multifunctional protective solution for paper protection is characterized in that: the weight portions are as follows: 48-67 parts of epsilon-polylysine modified chitosan carbamate (CS-PL-FEC) and 27-34 parts of taro starch phosphate;
the epsilon-polylysine modified chitosan-based carbamate (CS-PL-FEC) is prepared by the following steps:
sequentially adding distilled water and epsilon-polylysine (epsilon-PL) into a three-neck flask, sequentially adding N-hydroxysuccinimide coupling agent (NHS) and 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride condensing agent (EDC. HCl) after 30min, regulating the pH to 4-6 by using 0.6mol/L hydrochloric acid solution to dissolve solute, regulating the temperature to 30 ℃, reacting for 24 h, regulating the pH to 7-9 by using 0.5mol/L NaOH solution after the reaction is finished, precipitating the product, loading the product into a dialysis bag with the molecular weight cutoff of 8000, dialyzing for one week, removing unreacted epsilon-PL, NHS, EDC. HCl and byproducts, rotationally evaporating the cutoff liquid, and transferring the solid into a freeze dryer for drying to obtain epsilon-polylysine modified chitosan (CS-PL);
weighing CS-PL, placing in 1wt% dilute acetic acid, magnetically stirring at 30deg.C and 1600r/min for 3h to dissolve CS-PL, heating to 60deg.C, dropwise adding triethylamine as catalyst, mixing well, dropwise adding fluoroethylene carbonate (FEC), stirring for 8h, stopping reaction to obtain transparent liquid, placing transparent liquid into dialysis bag with molecular weight cut-off of 3000-5000, removing unreacted FEC, solvent acetic acid and triethylamine as catalyst, rotary evaporating the cut-off components, concentrating to obtain epsilon-polylysine modified chitosan-based carbamate (CS-PL-FEC) glue solution with solute mass fraction of 1-10wt%;
adding CS-PL-FEC glue solution into a three-neck flask, adding taro starch phosphate into the glue solution CS-PL-FEC under the conditions of magnetic stirring at room temperature and 800r/min, and uniformly stirring to obtain CS-PL-FEC/taro starch phosphate multifunctional protective solution;
the weight volume ratio of the Chitosan (CS), distilled water, epsilon-polylysine (epsilon-PL), N-hydroxysuccinimide coupling agent (NHS), 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride condensing agent (EDC & HCl), epsilon-polylysine modified chitosan (CS-PL), dilute acetic acid, triethylamine, fluoroethylene carbonate (FEC), epsilon-polylysine modified chitosan carbamate (CS-PL-FEC) and taro starch phosphate is as follows: 1:100:0.6587-0.9867:0.11895:0.1975-0.5923:1:100:0.02-0.08:0.7857:63-78:18-28.
2. The CS-PL-FEC/taro starch phosphate multifunctional protective solution for paper protection according to claim 1, wherein: the weight portions are as follows: 67 parts of epsilon-polylysine modified chitosan carbamate (CS-PL-FEC) and 34 parts of taro starch phosphate;
the epsilon-polylysine modified chitosan-based carbamate (CS-PL-FEC) is prepared by the following steps:
taking 1g (CS) of chitosan into a three-neck flask, sequentially adding 100g of distilled water and 0.9867g of epsilon-polylysine (epsilon-PL), after 30min, sequentially adding 0.11895g of N-hydroxysuccinimide coupling agent (NHS) and 0.5923g of 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride condensing agent (EDC. HCl), regulating the pH to 4-6 by using 0.6mol/L hydrochloric acid solution to fully dissolve the solute, regulating the temperature to 30 ℃, reacting for 24 hours, regulating the pH to 7-9 by using 0.5mol/L NaOH solution after the reaction is finished, precipitating the product, loading the product into a dialysis bag with a cut-off molecular weight of 8000, dialyzing for one week, removing unreacted epsilon-PL, NHS, EDC. HCl and byproducts, rotationally evaporating the cut-off solution, transferring the solid into a freeze dryer, and drying to obtain epsilon-polylysine modified chitosan (CS-PL);
weighing 1gCS-PL, placing in 100ml of 1wt% dilute acetic acid, magnetically stirring at 30deg.C and 1600r/min for 3h to dissolve CS-PL, heating to 60deg.C, dropwise adding 0.04g of catalyst triethylamine, mixing, slowly dropwise adding 0.7857g of fluoroethylene carbonate (FEC), stirring for 8h, stopping reaction to obtain transparent liquid, placing the transparent liquid into dialysis bag with molecular weight cut-off of 3000-5000, removing unreacted FEC, solvent acetic acid and catalyst triethylamine, rotationally evaporating the cut-off components, and concentrating to obtain epsilon-polylysine modified chitosan-based carbamate (CS-PL-FEC) glue solution with solute mass fraction of 1wt% -10wt%;
71g of CS-PL-FEC glue solution is weighed and added into a three-neck flask, 28g of taro starch phosphate is added into the glue solution CS-PL-FEC under the condition of magnetic stirring at room temperature and 800r/min, and the stirring is uniform, so that the CS-PL-FEC/taro starch phosphate multifunctional protective solution is obtained.
3. The CS-PL-FEC/taro starch phosphate multifunctional protective solution for paper protection according to claim 1, wherein: the weight portions are as follows: 67 parts of epsilon-polylysine modified chitosan carbamate (CS-PL-FEC) and 27 parts of taro starch phosphate;
the epsilon-polylysine modified chitosan-based carbamate (CS-PL-FEC) is prepared by the following steps:
taking 1g (CS) of chitosan into a three-neck flask, sequentially adding 100g of distilled water and 0.6587g of epsilon-polylysine (epsilon-PL), after 30min, sequentially adding 0.11895g of N-hydroxysuccinimide coupling agent (NHS) and 0.1975g of 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride condensing agent (EDC. HCl), regulating the pH to 4-6 by using 0.6mol/L hydrochloric acid solution to fully dissolve the solute, regulating the temperature to 30 ℃, reacting for 24 h, regulating the pH to 7-9 by using 0.5mol/L NaOH solution after the reaction is finished, precipitating the product, loading the product into a dialysis bag with a cut-off molecular weight of 8000, dialyzing for one week, removing unreacted epsilon-PL, NHS, EDC. HCl and byproducts, rotationally evaporating the cut-off solution, transferring the solid into a freeze dryer, and drying to obtain epsilon-polylysine modified chitosan (CS-PL);
weighing 1gCS-PL, placing in 100ml of 1wt% dilute acetic acid, magnetically stirring at 30deg.C and 1600r/min for 3h to dissolve CS-PL, heating to 60deg.C, dropwise adding 0.06g of catalyst triethylamine, mixing, slowly dropwise adding 0.7857g of fluoroethylene carbonate (FEC), stirring for 8h, stopping reaction to obtain transparent liquid, placing the transparent liquid into dialysis bag with molecular weight cut-off of 3000-5000, removing unreacted FEC, solvent acetic acid and catalyst triethylamine, rotationally evaporating the cut-off components, and concentrating to obtain epsilon-polylysine modified chitosan-based carbamate (CS-PL-FEC) glue solution with solute mass fraction of 1wt% -10wt%;
63g of CS-PL-FEC glue solution is weighed and added into a three-neck flask, 22g of taro starch phosphate is added into the glue solution CS-PL-FEC under the condition of magnetic stirring at room temperature and 800r/min, and the mixture is stirred uniformly to obtain the CS-PL-FEC/taro starch phosphate multifunctional protective solution.
4. The CS-PL-FEC/taro starch phosphate multifunctional protective solution for paper protection according to claim 1, wherein: the weight portions are as follows: 58 parts of epsilon-polylysine modified chitosan carbamate (CS-PL-FEC) and 31 parts of taro starch phosphate;
the epsilon-polylysine modified chitosan-based carbamate (CS-PL-FEC) is prepared by the following steps:
taking 1g (CS) of chitosan into a three-neck flask, sequentially adding 100g of distilled water and 0.6587g of epsilon-polylysine (epsilon-PL), after 30min, sequentially adding 0.11895g of N-hydroxysuccinimide coupling agent (NHS) and 0.5923g of 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride condensing agent (EDC. HCl), regulating the pH to 4-6 by using 0.6mol/L hydrochloric acid solution to fully dissolve the solute, regulating the temperature to 30 ℃, reacting for 24 hours, regulating the pH to 7-9 by using 0.5mol/L NaOH solution after the reaction is finished, precipitating the product, loading the product into a dialysis bag with a cut-off molecular weight of 8000, dialyzing for one week, removing unreacted epsilon-PL, NHS, EDC. HCl and byproducts, rotationally evaporating the cut-off solution, transferring the solid into a freeze dryer, and drying to obtain epsilon-polylysine modified chitosan (CS-PL);
weighing 1gCS-PL, placing in 100ml of 1wt% dilute acetic acid, magnetically stirring at 30deg.C and 1600r/min for 3h to dissolve CS-PL, heating to 60deg.C, dropwise adding 0.08g of catalyst triethylamine, mixing, slowly dropwise adding 0.7857g of fluoroethylene carbonate (FEC), stirring for 8h, stopping reaction to obtain transparent liquid, placing the transparent liquid into dialysis bag with molecular weight cut-off of 3000-5000, removing unreacted FEC, solvent acetic acid and catalyst triethylamine, rotationally evaporating the cut-off components, and concentrating to obtain epsilon-polylysine modified chitosan-based carbamate (CS-PL-FEC) glue solution with solute mass fraction of 1wt% -10wt%;
78g of CS-PL-FEC glue solution is weighed and added into a three-neck flask, 20g of taro starch phosphate is added into the glue solution CS-PL-FEC under the condition of magnetic stirring at room temperature and 800r/min, and the stirring is uniform, so that the CS-PL-FEC/taro starch phosphate multifunctional protective solution is obtained.
5. The CS-PL-FEC/taro starch phosphate multifunctional protective solution for paper protection according to claim 1, wherein: the deacetylation degree of the chitosan is more than or equal to 95 percent, and the viscosity is 100-200 mPa.s; the epsilon-polylysine has a purity of 50%; the purity of the fluoroethylene carbonate is 98%; the purity of the triethylamine is 99.7%; the taro starch phosphate, ds=0.03; the alkali solution is sodium hydroxide solution with the concentration of 0.5 mol/L; the acid solution is hydrochloric acid solution with the concentration of 0.6 mol/L; the purity of the 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride is 98.5 percent; the purity of the N-hydroxysuccinimide is 98%; the dilute acetic acid is 1wt% acetic acid solution.
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| WO2003042250A1 (en) * | 2001-11-15 | 2003-05-22 | Biosyntech Canada Inc. | Composition and method to homogeneously modify or cross-link chitosan under neutral conditions |
| CA2630608A1 (en) * | 2005-12-08 | 2007-06-14 | Ciba Holding Inc. | A process for the preparation of hydroxy polymer esters and their use |
| CN111270554A (en) * | 2020-03-19 | 2020-06-12 | 郑州大学 | Amphipathic cationic chitosan-phosphate starch composite strengthening liquid for paper protection |
| CN111424464A (en) * | 2020-03-19 | 2020-07-17 | 郑州大学 | Preparation method and application of modified chitosan/silicon composite reinforcement liquid for paper protection |
| CN115110340A (en) * | 2022-04-24 | 2022-09-27 | 郑州大学 | Multifunctional protective liquid for paper |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| WO2003042250A1 (en) * | 2001-11-15 | 2003-05-22 | Biosyntech Canada Inc. | Composition and method to homogeneously modify or cross-link chitosan under neutral conditions |
| CA2630608A1 (en) * | 2005-12-08 | 2007-06-14 | Ciba Holding Inc. | A process for the preparation of hydroxy polymer esters and their use |
| CN111270554A (en) * | 2020-03-19 | 2020-06-12 | 郑州大学 | Amphipathic cationic chitosan-phosphate starch composite strengthening liquid for paper protection |
| CN111424464A (en) * | 2020-03-19 | 2020-07-17 | 郑州大学 | Preparation method and application of modified chitosan/silicon composite reinforcement liquid for paper protection |
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