Disclosure of Invention
In view of the above situation, in order to overcome the defects of the prior art, the invention aims to provide a paper cultural relic reinforcing liquid for paper cultural relic protection, which can effectively solve the problem that the strength and flexibility of paper cannot be simultaneously increased by the conventional reinforcing liquid for paper cultural relic protection.
The technical scheme of the invention is that a paper cultural relic reinforcing liquid for protecting the paper cultural relics is prepared from the following components in percentage by weight: 5-30% of nano silicon dioxide-based polyurethane, 5-30% of hydroxyl-terminated epoxy cyclohexane-epichlorohydrin-based polyurethane, 5-30% of organosilicon-based polyurethane and 10-85% of ethyl acetate are uniformly mixed to prepare the polyurethane;
the nano silicon dioxide-based polyurethane comprises the following components in parts by weight: 40g of hexamethylene diisocyanate trimer, 0.5g of nano silicon dioxide, 0.1g of dibutyltin dilaurate and 30g of ethyl acetate, wherein the nano silicon dioxide is placed in a vacuum drying oven and dried for 10-24h, and moisture is removed to obtain dried nano silicon dioxide; adding hexamethylene diisocyanate trimer into ethyl acetate to obtain mixed solution; adding dried nano silicon dioxide into the mixed solution, adding dibutyltin dilaurate, heating to 70 ℃, reacting, measuring the content of isocyanate group (-NCO) every other hour, stopping the reaction when the content of the isocyanate group (-NCO) is not changed any more, and removing ethyl acetate by reduced pressure distillation to obtain nano silicon dioxide-based polyurethane;
the hydroxyl-terminated epoxy cyclohexane-epichlorohydrin-based polyurethane is prepared from the following components in parts by weight: 5g of hydroxyl-terminated epoxy cyclohexane-epoxy chloropropane copolyether, 40g of hexamethylene diisocyanate tripolymer, 0.1g of dibutyltin dilaurate and 30g of ethyl acetate, wherein the hydroxyl-terminated epoxy cyclohexane-epoxy chloropropane copolyether, the hexamethylene diisocyanate tripolymer and the dibutyltin dilaurate are added into the ethyl acetate, the mixture is heated to 70 ℃ for reaction, the content of isocyanate group (-NCO) is measured every other hour, and when the weight content of the isocyanate group (-NCO) is not changed any more, the reaction is terminated, so that hydroxyl-terminated epoxy cyclohexane-epoxy chloropropane polyurethane is obtained;
the organic silicon-based polyurethane comprises the following components in parts by weight: 30g of hydroxyl-terminated polydimethylsiloxane, 40g of hexamethylene diisocyanate trimer, 0.2g of dibutyltin dilaurate and 30g of ethyl acetate, wherein the hydroxyl-terminated polydimethylsiloxane, the hexamethylene diisocyanate trimer and the dibutyltin dilaurate are added into the ethyl acetate, the mixture is heated to 70 ℃ for reaction, the content of isocyanate group (-NCO) is measured every other hour, when the content of the isocyanate group (-NCO) is not changed any more, the reaction is terminated, and the ethyl acetate is removed through reduced pressure distillation, so that the organosilicon-based polyurethane is obtained.
The paper cultural relic protection material prepared by the invention has reversibility, can remove the protection film under the condition of no damage or slight damage, is an innovation on the protection and solidification liquid of the paper cultural relic, and has great economic and social benefits.
Detailed Description
The following detailed description of specific embodiments of the invention is provided in connection with specific use cases and examples.
Example 1: a paper cultural relic reinforcing liquid comprises the following components in percentage by weight: 10% of nano silicon dioxide-based polyurethane, 10% of hydroxyl-terminated epoxy cyclohexane-epichlorohydrin-based polyurethane, 10% of organosilicon-based polyurethane and 70% of ethyl acetate are uniformly mixed to prepare the polyurethane adhesive;
the nano silicon dioxide-based polyurethane comprises the following components in parts by weight: 40g of hexamethylene diisocyanate trimer, 0.5g of nano silicon dioxide, 0.1g of dibutyltin dilaurate and 30g of ethyl acetate, wherein the nano silicon dioxide is placed in a vacuum drying oven and dried for 10-24h, and moisture is removed to obtain dried nano silicon dioxide; adding hexamethylene diisocyanate trimer into ethyl acetate to obtain mixed solution; adding dried nano silicon dioxide into the mixed solution, adding dibutyltin dilaurate, heating to 70 ℃, reacting, measuring the content of isocyanate group (-NCO) every other hour, stopping the reaction when the content of the isocyanate group (-NCO) is not changed any more, and removing ethyl acetate by reduced pressure distillation to obtain nano silicon dioxide-based polyurethane;
the hydroxyl-terminated epoxy cyclohexane-epichlorohydrin-based polyurethane is prepared from the following components in parts by weight: 5g of hydroxyl-terminated epoxy cyclohexane-epoxy chloropropane copolyether, 40g of hexamethylene diisocyanate tripolymer, 0.1g of dibutyltin dilaurate and 30g of ethyl acetate, wherein the hydroxyl-terminated epoxy cyclohexane-epoxy chloropropane copolyether, the hexamethylene diisocyanate tripolymer and the dibutyltin dilaurate are added into the ethyl acetate, the mixture is heated to 70 ℃ for reaction, the content of isocyanate group (-NCO) is measured every other hour, and when the weight content of the isocyanate group (-NCO) is not changed any more, the reaction is terminated, so that hydroxyl-terminated epoxy cyclohexane-epoxy chloropropane polyurethane is obtained;
the organic silicon-based polyurethane comprises the following components in parts by weight: 30g of hydroxyl-terminated polydimethylsiloxane, 40g of hexamethylene diisocyanate trimer, 0.2g of dibutyltin dilaurate and 30g of ethyl acetate, wherein the hydroxyl-terminated polydimethylsiloxane, the hexamethylene diisocyanate trimer and the dibutyltin dilaurate are added into the ethyl acetate, the mixture is heated to 70 ℃ for reaction, the content of isocyanate group (-NCO) is measured every other hour, when the content of the isocyanate group (-NCO) is not changed any more, the reaction is terminated, and the ethyl acetate is removed through reduced pressure distillation, so that the organosilicon-based polyurethane is obtained.
Example 2: a paper cultural relic reinforcing liquid comprises the following components in percentage by weight: 10% of nano silicon dioxide-based polyurethane, 15% of hydroxyl-terminated epoxy cyclohexane-epichlorohydrin-based polyurethane, 15% of organosilicon-based polyurethane and 60% of ethyl acetate are uniformly mixed to prepare the polyurethane; the preparation methods of the nano-silica-based polyurethane, the hydroxyl-terminated epoxycyclohexane-epichlorohydrin-based polyurethane and the organosilicon-based polyurethane are the same as in example 1.
Example 3: a paper cultural relic reinforcing liquid comprises the following components in percentage by weight: 10% of nano silicon dioxide-based polyurethane, 20% of hydroxyl-terminated epoxy cyclohexane-epichlorohydrin-based polyurethane, 20% of organosilicon-based polyurethane and 50% of ethyl acetate are uniformly mixed to prepare the polyurethane adhesive; the preparation methods of the nano-silica-based polyurethane, the hydroxyl-terminated epoxycyclohexane-epichlorohydrin-based polyurethane and the organosilicon-based polyurethane are the same as in example 1.
Example 4: a paper cultural relic reinforcing liquid comprises the following components in percentage by weight: 15% of nano silicon dioxide-based polyurethane, 10% of hydroxyl-terminated epoxy cyclohexane-epichlorohydrin-based polyurethane, 15% of organosilicon-based polyurethane and 60% of ethyl acetate are uniformly mixed to prepare the polyurethane; the preparation methods of the nano-silica-based polyurethane, the hydroxyl-terminated epoxycyclohexane-epichlorohydrin-based polyurethane and the organosilicon-based polyurethane are the same as in example 1.
Example 5: a paper cultural relic reinforcing liquid comprises the following components in percentage by weight: the nano silicon dioxide-based polyurethane is prepared by uniformly mixing 15% of nano silicon dioxide-based polyurethane, 15% of hydroxyl-terminated epoxy cyclohexane-epichlorohydrin-based polyurethane, 20% of organosilicon-based polyurethane and 50% of ethyl acetate; the preparation methods of the nano-silica-based polyurethane, the hydroxyl-terminated epoxycyclohexane-epichlorohydrin-based polyurethane and the organosilicon-based polyurethane are the same as in example 1.
Example 6: a paper cultural relic reinforcing liquid comprises the following components in percentage by weight: 15% of nano silicon dioxide-based polyurethane, 20% of hydroxyl-terminated epoxy cyclohexane-epichlorohydrin-based polyurethane, 10% of organosilicon-based polyurethane and 55% of ethyl acetate are uniformly mixed to prepare the polyurethane adhesive; the preparation methods of the nano-silica-based polyurethane, the hydroxyl-terminated epoxycyclohexane-epichlorohydrin-based polyurethane and the organosilicon-based polyurethane are the same as in example 1.
Example 7: a paper cultural relic reinforcing liquid comprises the following components in percentage by weight: 20% of nano silicon dioxide-based polyurethane, 10% of hydroxyl-terminated epoxy cyclohexane-epichlorohydrin-based polyurethane, 20% of organosilicon-based polyurethane and 50% of ethyl acetate are uniformly mixed to prepare the polyurethane adhesive; the preparation methods of the nano-silica-based polyurethane, the hydroxyl-terminated epoxycyclohexane-epichlorohydrin-based polyurethane and the organosilicon-based polyurethane are the same as in example 1.
When the paper is used specifically, the cut paper (210mm multiplied by 297mm) is soaked in the reinforcing liquid provided by the invention (or the reinforcing liquid provided by the invention is sprayed on the paper) for 2-15min, and then the paper is taken out and dried naturally.
The results of the performance indexes of the paper treated by the reinforcing liquid prepared by the methods of examples 1, 2, 3, 4, 5, 6 and 7 of the invention are shown in Table 1:
table 1:
the tensile strength test of the paper in the table is determined according to national standard GB/T12914-2008; the folding endurance of the paper is determined according to national standard GB/T457-2008; the tearing degree of the paper is measured according to the national standard GB/455-2002 of China; the glossiness of the paper is measured according to the national standard GB/T8941-2013; the whiteness of the paper is measured according to the national standard GB/T7974-2002 of China.
Aging test: the comparison of the performance indexes of the paper treated by the reinforcing liquid of the invention and the blank paper before and after aging is shown in Table 2:
table 2:
the aging experiments in the above table were determined according to national standard GB/T464-2008.
Compared with the prior art, the invention has the following beneficial technical effects:
1. the nano silicon dioxide-based polyurethane has the effects of absorbing and shielding ultraviolet rays of 200-400 nm and simultaneously has the effects of enhancing and toughening, so that the mechanical property can be enhanced and the ultraviolet resistance of the cultural relics can be improved by over 50% by adding the nano silicon dioxide-based polyurethane into a reinforcing liquid.
2. The polyurethane prepared by synthesizing the epoxy cyclohexane-epoxy chloropropane copolyether polyurethane has small molecular weight, good permeability and colorless and transparent appearance, and can improve the mechanical property of paper and keep good glossiness by more than 40 percent when being applied to the reinforcement protection of paper cultural relics;
3. the organosilicon-based polyurethane contains Si-O bonds with high bond energy (422.2kJ/m O l) on organosilicon, and the unimolecular volume of the organosiloxane is large, and the cohesive energy density is low, so that the organosiloxane is introduced to the main chain or the side chain of the polyurethane molecule, and the tolerance performance of the product can be improved. The invention combines the advantages of polysiloxane and polyurethane to obtain the paper reinforcing material with excellent performance, and particularly, the folding resistance of the paper is obviously improved, and the folding resistance times can be improved by more than 2 times.
4. The invention has scientific and reasonable formula, rich raw materials, easy production and preparation and good use effect. The paper has the advantages of enhancing the tensile strength of the paper, keeping the flexibility of the paper, having higher transparency, avoiding the defect that the traditional reinforcing material can only enhance the single performance of the paper, prolonging the preservation life of the paper cultural relics by more than 3 times, having strong ageing resistance and improving the ornamental and research values of the paper cultural relics. The paper cultural relic protection material prepared by the invention has reversibility, can remove the protection film under the condition of no damage or slight damage, is an innovation on paper cultural relic protection, and has great economic and social benefits.