A green, recyclable, high-toughness corrugated paperboard and its production process

Abstract

The present invention relates to a green, recyclable, high-toughness corrugated paperboard and a production process thereof, and belongs to the technical field of corrugated paperboard preparation. The corrugated paperboard comprises corrugated paper and face paper adhered to both sides of the corrugated paperboard, and the corrugated paperboard is composed of multiple layers of modified corrugated paperboard and an adhesive layer coated on the surface of the modified corrugated paperboard, and the adhesive layer is obtained by uniformly coating the modified corn starch glue on the surface of the modified corrugated paperboard through a glue roller. The present invention adds amino groups and hydroxyl groups rich in the surface of the modified corrugated paperboard, thereby improving the interface bonding degree between the corrugated paperboard and the modified corn starch glue, and the corrugated paperboard structure after the modified corn starch is cured is more compact, has a higher degree of cross-linking, and has stronger mechanical properties. At the same time, the amino groups and hydroxyl groups in the modified corrugated paperboard can both undergo a cross-linking reaction with the isocyanate groups in the modified corn starch glue, and they work together to improve the toughness, adhesion, and supporting strength of the corrugated paperboard.

Description

Technical Field

[0001] The invention belongs to the technical field of corrugated paperboard preparation, and in particular relates to a green, recyclable, high-toughness corrugated paperboard and a production process thereof. Background Art

[0002] Corrugated paperboard is generally made of boxboard and corrugated base paper, among which corrugated base paper plays a "skeleton role" in corrugated paperboard. The quality of corrugated base paper directly affects the compressive strength of corrugated paperboard. Corrugated base paper is generally made of a mixture of one or more of wood pulp, straw pulp and waste paper pulp. With the deepening of environmental protection and resource recycling awareness, and the penetration of green packaging concepts, waste paper has become one of the main raw materials for the production of corrugated base paper. However, the paper fibers in recycled waste paper have the disadvantages of increased fiber stiffness, decreased swelling ability, and poor wet toughness, which causes the toughness of the prepared corrugated base paper to decrease and cannot meet the needs of actual life. In order to improve the quality of corrugated base paper and make the prepared corrugated board have high toughness to meet the needs of daily life, people have improved the raw materials and processes of high-strength corrugated board by papermaking, summarized the characteristics of high-strength corrugated board made of straw and cotton as raw materials, conducted scientific research and testing, and discussed the strength and other properties of this kind of corrugated board theoretically.

[0003] However, in the prior art, the secondary fibers of corrugated paper have low toughness and poor compatibility between straw and cotton. It is difficult to process and manufacture them with better technology in a short period of time, and the secondary recycling time of the product is relatively long and cannot meet the needs of people's daily life. Summary of the invention

[0004] The purpose of the present invention is to provide a green, recyclable, high-toughness corrugated paperboard and a production process thereof to solve the following technical problems:

[0005] In the prior art, the fiber stiffness of paper fibers recycled from waste paper increases, the swelling ability decreases, and the wet toughness deteriorates, resulting in a decrease in the toughness of corrugated paper obtained after the waste paper is recycled and cannot meet the actual needs of life.

[0006] How to improve the toughness of corrugated cardboard and meet the requirements of green, recyclable and highly operational technology.

[0007] The purpose of the present invention can be achieved through the following technical solutions:

[0008] A green, recyclable, high-toughness corrugated paperboard comprises corrugated paper and face paper adhered to both sides of the corrugated paper. The corrugated paper is composed of multiple layers of modified corrugated paper and an adhesive layer coated on the surface of the modified corrugated paper. The adhesive layer is obtained by uniformly coating modified corn starch glue on the surface of the modified corrugated paper through a glue coating roller.

[0009] A production process of green, recyclable, high-toughness corrugated paperboard comprises the following steps:

[0010] (1) uniformly coating the surface of the modified corrugated paper with modified corn starch glue by a glue roller, and controlling the glue application amount to 10-15 g / m2;

[0011] (2) laminating the modified corrugated paper after sizing, heating the drying oven to 80-90° C. for drying, and sending the dried paper to a corrugator for corrugation to obtain corrugated paper;

[0012] (3) Coat both sides of the corrugated paper with styrene acrylic emulsion, control the amount of styrene acrylic emulsion used to 1-5g / m2, and press it with the surface paper. After curing and drying at 50°C for 1-2h, the corrugated board is obtained.

[0013] As a further solution of the present invention: the preparation method of modified corrugated paper comprises the following steps:

[0014] S1. Add isocyanic anhydride, tris(hydroxymethyl)aminomethane) and ethyl acetate into reaction kettle A, stir evenly, heat to 70-80°C, keep warm for 12h, filter, wash and dry to obtain intermediate 1.

[0015] S2, add intermediate 1, 3-mercapto-1,2-propylene glycol and deionized water into reactor B, stir evenly, add 1-(2-hydroxyethyl)-3-methylimidazole chloride, heat to 70-80°C, keep warm for 1-2h to obtain intermediate 2;

[0016] S3, adding pulp, dimethyl sulfoxide and 1,8-diazabicycloundec-7-ene to reactor C, stirring evenly, slowly introducing CO2 to 1-2MPa, slowly releasing, repeating 3 times, then slowly introducing CO2 to stabilize to 0.2MPa, heating to 50-60°C, keeping warm for 1-2h, adding intermediate 2 to reactor C, ultrasonically dispersing, heating to 40-50°C, stirring to react for 2-3h, filtering, washing and drying to obtain modified pulp;

[0017] S4. Add 1200-1800 parts by weight of modified pulp into a fiber separator, then add 4-6 parts by weight of a sizing agent and 4-6 parts by weight of a papermaking filler for dispersion, and then transfer to a sheet maker, add water to adjust the concentration on the screen to 0.1-0.5wt%, stir and disperse, let stand for 5-10s, filter and dehydrate, mechanically press, and dry to obtain modified corrugated paper.

[0018] As a further solution of the present invention: in S1, the mass ratio of isatoic anhydride: trishydroxymethylaminomethane: ethyl acetate is 15-20: 10-15: 150-200.

[0019] As a further solution of the present invention: the mass ratio of intermediate 1 in S2: 3-mercapto-1,2-propylene glycol: deionized water: 1-(2-hydroxyethyl)-3-methylimidazole chloride is 20-30: 20-30: 100-150: 20-25.

[0020] As a further solution of the present invention: in S3, the mass ratio of pulp: dimethyl sulfoxide: 1,8-diazabicycloundec-7-ene: intermediate II is 300-400: 300-500: 40-60: 40-60.

[0021] As a further scheme of the present invention: the preparation method of modified corn starch glue comprises the following steps: adding corn starch and deionized water into a reaction kettle D, heating to 30-40°C, mechanically stirring for 5-10 minutes, cooling to room temperature, adding a saturated sodium carbonate solution dropwise to adjust the pH to 9, adding 4-(maleimido)phenyl isocyanate and a 10wt% borax aqueous solution, continuing to stir the reaction for 1-2 hours, washing and drying to obtain the modified corn starch glue.

[0022] As a further solution of the present invention: the usage ratio of corn starch, deionized water, 4-(maleimido)phenyl isocyanate and 10wt% borax aqueous solution is 0.5-1mol:50-60mL:1-2mol:0.4-0.6mL.

[0023] As a further solution of the present invention: the sizing agent is a mixture of saponified rosin glue, cationic rosin glue and dispersed rosin glue in a mass ratio of 1:1:1.

[0024] As a further solution of the present invention: the surface paper is any one of kraft paper, imitation kraft paper and white board paper.

[0025] As a further solution of the present invention: the papermaking filler is a mixture of talcum powder and calcium carbonate in a mass ratio of 1:1.

[0026] As a further scheme of the present invention: the preparation method of the pulp is as follows: 90-100 parts by weight of waste corrugated paper and 200-300 parts by weight of deionized water are put into a pulping tank until the paper product is pulped, stirred for 1-2 hours, and then 0.5-1mL 0.2vt% PAM-LB-3 anionic polyacrylamide is added, and stirring is continued for 0.5-1h, impurities are removed by filtering and sieving, and pulp is obtained after washing.

[0027] Beneficial effects of the present invention:

[0028] The present application recycles waste corrugated paper, which is green and environmentally friendly. The present invention uses tris(hydroxymethyl)aminomethane and isatoic anhydride as raw materials, uses ethyl acetate as solvent, and undergoes nucleophilic substitution to obtain intermediate 1; uses intermediate 1 and 3-mercapto-1,2-propanediol as raw materials, and uses 1-(2-hydroxyethyl)-3-methylimidazole chloride as an ion catalyst to undergo an esterification reaction to obtain intermediate 2; and uses waste corrugated paper as raw material to prepare paper pulp. A mixed solution of dimethyl sulfoxide, 1,8-diazabicycloundec-7-ene and CO2 is further used as a solvent to dissolve the cellulose in the paper pulp, and 1,8-diazabicycloundec-7-ene is used as a catalyst to cause the hydroxyl groups of the fibers in the paper pulp to undergo a transesterification reaction with the ester groups in intermediate 2 to obtain modified paper pulp, and the modified paper pulp is treated to obtain modified corrugated paper. The present invention uses deionized water as solvent and saturated sodium carbonate as catalyst, and the hydroxyl groups in starch react with the isocyanate groups in 4-maleimidephenyl isocyanate to obtain modified corn starch glue. The modified corrugated paper prepared by the present invention has a surface rich in amine groups and hydroxyl groups, which improves the interface bonding degree between the corrugated base paper and the modified corn starch glue. The active amine groups and hydroxyl groups on the surface of the modified corrugated paper can react with the isocyanate groups in the modified corn starch glue to allow the modified corrugated paper to be anchored inside the corn starch through chemical bonds, acting as a stress concentration point, absorbing impact, and improving the toughness of the corrugated paperboard. Secondly, 4-maleimidephenyl isocyanate and borax are added to the corn starch curing system, and the hydroxyl groups in the corn starch can react with 4-maleimidephenyl isocyanate to form a cross-linked reaction. The isocyanate group of aminophenyl ester undergoes chemical crosslinking, so that the interaction between the chain and chain of corn starch and 4-maleimide phenyl isocyanate is stronger, so that the structure of the corrugated board after the modified corn starch is cured is tighter, the degree of crosslinking is higher, and the mechanical properties are stronger; borax is used as a crosslinking agent to enhance the crosslinking and thickening effect between the modified corn starch glue and the modified corrugated paper; thirdly, the amine group and the hydroxyl group in the modified corrugated paper can be chemically crosslinked with the isocyanate group in the modified corn starch glue, further improving the toughness, adhesion and support strength of the corrugated board. The present invention provides a production process for green and recyclable high-toughness corrugated board, which solves the technical problem that the corrugated base paper in the corrugated board in the prior art has low secondary fiber toughness, and the compatibility between straw and cotton is poor, which leads to the manufactured corrugated board cannot meet people's daily life needs. The green and recyclable high-toughness corrugated board prepared by the present invention has high bonding strength, high edge pressure strength and high bursting strength, and has more excellent toughness, more stable bonding performance and more solid support strength. DETAILED DESCRIPTION

[0029] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] Embodiment 1 A method for preparing modified corn starch glue comprises the following steps:

[0031] 0.5 mol corn starch and 50 mL deionized water were added to reactor D, the temperature was raised to 30 ° C, mechanically stirred for 5 min, cooled to room temperature, saturated sodium carbonate solution was added dropwise to adjust the pH to 9, 1 mol 4-(maleimido)phenyl isocyanate and 0.4 mL 10 wt% borax aqueous solution were added, the reaction was continued with stirring for 1 h, and the modified corn starch glue was obtained by washing and drying.

[0032] Example 2

[0033] A preparation method of modified corn starch glue comprises the following steps: adding 0.75 mol corn starch and 55 mL deionized water into a reaction kettle D, heating to 35° C., mechanically stirring for 7.5 min, cooling to room temperature, dripping saturated sodium carbonate solution to adjust the pH to 9, adding 1.5 mol 4-(maleimido)phenyl isocyanate and 0.5 mL 10 wt % borax aqueous solution, continuing stirring and reacting for 1.5 h, washing and drying to obtain the modified corn starch glue.

[0034] Example 3

[0035] A method for preparing modified corn starch glue comprises the following steps:

[0036] Add 1 mol corn starch and 60 mL deionized water into reactor D, heat to 40 ° C, stir mechanically for 10 min, cool to room temperature, add saturated sodium carbonate solution to adjust the pH to 9, add 2 mol 4-(maleimido)phenyl isocyanate and 0.6 mL 10 wt% borax aqueous solution, continue stirring and reacting for 2 h, wash and dry to obtain modified corn starch gum.

[0037] Example 4

[0038] A method for preparing modified corrugated paper comprises the following steps:

[0039] S1. Put 900g of waste corrugated paper into a pulping tank, add 2000mL of deionized water until the paper is pulped, stir for 1h, then add 5mL of 0.2vt% PAM-LB-3 anionic polyacrylamide, continue stirring for 0.5h, filter and sieve to remove impurities, and obtain pulp after washing;

[0040] S2, add 15g of isatoic anhydride, 10g of tris(hydroxymethyl)aminomethane and 170mL of ethyl acetate into reactor A, stir evenly, heat to 70-80°C, keep warm for 12h, filter, wash and dry to obtain intermediate 1;

[0041] S3, add 20g of intermediate 1, 20g of 3-mercapto-1,2-propylene glycol, and 100mL of deionized water into reactor B, stir evenly, add 20g of 1-(2-hydroxyethyl)-3-methylimidazole chloride, heat to 70°C, and keep the temperature for 1h to obtain intermediate 2;

[0042] S4, add 150g of pulp, 140mL of dimethyl sulfoxide and 20g of 1,8-diazabicycloundec-7-ene to reactor C, stir evenly, slowly introduce CO2 to 1MPa, slowly release, repeat 3 times, then slowly introduce CO2 to stabilize to 0.2MPa, heat to 50°C to obtain intermediate three mixed liquid, ultrasonically disperse the intermediate three mixed liquid and 20g of intermediate two, heat to 40°C, stir to react for 2h, filter, wash and dry to obtain modified pulp;

[0043] S5, adding 120g of modified pulp into a fiber separator, then adding 0.4g of sizing agent and 0.4g of papermaking filler for dispersion, and then transferring to a sheet making machine, adding water to adjust the screen concentration to 0.1wt%, stirring and dispersing, standing for 10s, filtering and dehydrating, mechanically pressing, and drying to obtain modified corrugated paper;

[0044] The papermaking filler is a mixture of talcum powder and calcium carbonate in a mass ratio of 1:1, and the sizing agent is a mixture of saponified rosin glue, cationic rosin glue and dispersed rosin glue in a mass ratio of 1:1:1.

[0045] Example 5

[0046] A method for preparing modified corrugated paper comprises the following steps:

[0047] S1. Put 950g of waste corrugated paper into a pulping tank, add 2500mL of deionized water until the paper is pulped, stir for 1h, then add 7mL of 0.2vt% PAM-LB-3 anionic polyacrylamide, continue stirring for 0.5h, filter and sieve to remove impurities, and obtain pulp after washing;

[0048] S2, add 17g of isatoic anhydride, 18g of tris(hydroxymethyl)aminomethane and 200mL of ethyl acetate into reactor A, stir evenly, heat to 70-80°C, keep warm for 12h, filter, wash and dry to obtain intermediate 1;

[0049] S3, add 25g of intermediate 1, 25g of 3-mercapto-1,2-propylene glycol, and 130mL of deionized water into reactor B, stir evenly, add 23g of 1-(2-hydroxyethyl)-3-methylimidazole chloride, heat to 75°C, and keep the reaction for 1.5h to obtain intermediate 2;

[0050] S4, add 180g of pulp, 200mL of dimethyl sulfoxide and 25g of 1,8-diazabicycloundec-7-ene to reactor C, stir evenly, slowly introduce CO2 to 1MPa, slowly release, repeat 3 times, then slowly introduce CO2 to stabilize to 0.2MPa, heat to 50°C to obtain intermediate III mixed liquid, ultrasonically disperse the intermediate III mixed liquid and 25g of intermediate II, heat to 40°C, stir to react for 2h, filter, wash and dry to obtain modified pulp;

[0051] S5, adding 150g of modified pulp into a fiber separator, then adding 0.5g of sizing agent and 0.5g of papermaking filler for dispersion, and then transferring to a sheet making machine, adding water to adjust the screen concentration to 0.1wt%, stirring and dispersing, standing for 10s, filtering and dehydrating, mechanically pressing, and drying to obtain modified corrugated paper;

[0052] The papermaking filler is a mixture of talcum powder and calcium carbonate in a mass ratio of 1:1, and the sizing agent is a mixture of saponified rosin glue, cationic rosin glue and dispersed rosin glue in a mass ratio of 1:1:1.

[0053] Example 6

[0054] A method for preparing modified corrugated paper comprises the following steps:

[0055] S1. Put 1000g of waste corrugated paper into a pulping tank, add 3000mL of deionized water until the paper is pulped, stir for 1h, then add 10mL of 0.2vt% PAM-LB-3 anionic polyacrylamide, continue stirring for 0.5h, filter and sieve to remove impurities, and obtain pulp after washing;

[0056] S2, add 20g of isatoic anhydride, 15g of tris(hydroxymethyl)aminomethane and 220mL of ethyl acetate into reactor A, stir evenly, heat to 70-80°C, keep warm for 12h, filter, wash and dry to obtain intermediate 1;

[0057] S3, add 30g of intermediate 1, 30g of 3-mercapto-1,2-propylene glycol, and 150mL of deionized water into reactor B, stir evenly, add 25g of 1-(2-hydroxyethyl)-3-methylimidazole chloride, heat to 80°C, and keep the temperature for 2h to obtain intermediate 2;

[0058] S4, add 200g of pulp, 220mL of dimethyl sulfoxide and 30g of 1,8-diazabicycloundec-7-ene to reactor C, stir evenly, slowly introduce CO2 to 1MPa, slowly release, repeat 3 times, then slowly introduce CO2 to stabilize to 0.2MPa, heat to 50°C to obtain intermediate three mixed liquid, ultrasonically disperse the intermediate three mixed liquid and 30g of intermediate two, heat to 40°C, stir to react for 2h, filter, wash and dry to obtain modified pulp;

[0059] S5, adding 180g of modified pulp into a fiber separator, then adding 0.6g of sizing agent and 0.6g of papermaking filler for dispersion, and then transferring to a sheet making machine, adding water to adjust the screen concentration to 0.1wt%, stirring and dispersing, standing for 10s, filtering and dehydrating, mechanically pressing, and drying to obtain modified corrugated paper;

[0060] The papermaking filler is a mixture of talcum powder and calcium carbonate in a mass ratio of 1:1, and the sizing agent is a mixture of saponified rosin glue, cationic rosin glue and dispersed rosin glue in a mass ratio of 1:1:1.

[0061] Example 7

[0062] A production process of green recyclable high-toughness corrugated paperboard comprises the following steps:

[0063] (1) The modified corn starch glue prepared in Example 1 is evenly coated on the surface of the modified corrugated paper prepared in Example 4 by a glue roller, and the glue application amount is controlled to be 10 g / m2;

[0064] (2) laminating the modified corrugated paper after sizing, drying it in a drying oven at 80° C., and sending it to a corrugator for corrugation to obtain corrugated paper;

[0065] (3) Both sides of the corrugated paper are coated with styrene acrylic emulsion, the amount of which is controlled to be 5 g / m2, and the corrugated paper is pressed with kraft paper. After curing and drying at 50°C for 2 hours, the corrugated paperboard is obtained.

[0066] Example 8

[0067] A production process of green recyclable high-toughness corrugated paperboard comprises the following steps:

[0068] (1) The modified corn starch glue prepared in Example 2 is evenly coated on the surface of the modified corrugated paper prepared in Example 5 by a glue roller, and the glue application amount is controlled to be 10 g / m2;

[0069] (2) laminating the modified corrugated paper after sizing, drying it in a drying oven at 80° C., and sending it to a corrugator for corrugation to obtain corrugated paper;

[0070] (3) Both sides of the corrugated paper are coated with styrene acrylic emulsion, the amount of which is controlled to be 5 g / m2, and the corrugated paper is pressed with kraft paper. After curing and drying at 50°C for 2 hours, the corrugated paperboard is obtained.

[0071] Example 9

[0072] A production process of green recyclable high-toughness corrugated paperboard comprises the following steps:

[0073] (1) The modified corn starch glue prepared in Example 3 is evenly coated on the surface of the modified corrugated paper prepared in Example 6 by a glue roller, and the glue application amount is controlled to be 10 g / m2;

[0074] (2) laminating the modified corrugated paper after sizing, drying it in a drying oven at 80° C., and sending it to a corrugator for corrugation to obtain corrugated paper;

[0075] (3) Both sides of the corrugated paper are coated with styrene acrylic emulsion, the amount of which is controlled to be 5 g / m2, and the corrugated paper is pressed with kraft paper. After curing and drying at 50°C for 2 hours, the corrugated paperboard is obtained.

[0076] Comparative Example 1

[0077] A method for preparing modified corn starch glue comprises the following steps:

[0078] 0.5 mol corn starch and 50 mL deionized water were added to reactor D, the temperature was raised to 30°C, mechanically stirred for 5 min, cooled to room temperature, saturated sodium carbonate solution was added dropwise to adjust the pH to 9, 0.4 mL 10 wt% borax aqueous solution was added, the reaction was continued with stirring for 1 h, washed and dried to obtain modified corn starch gum.

[0079] Comparative Example 2

[0080] A method for preparing modified corrugated paper comprises the following steps:

[0081] S1. Put 900g of waste corrugated paper into a pulping tank, add 2000mL of deionized water until the paper is pulped, stir for 1h, then add 5mL of 0.2vt% PAM-LB-3 anionic polyacrylamide, continue stirring for 0.5h, filter and sieve to remove impurities, and obtain pulp after washing;

[0082] S2, add 150g of pulp, 140mL of dimethyl sulfoxide and 20g of 1,8-diazabicycloundec-7-ene into reactor C, stir evenly, slowly introduce CO2 to 1MPa, slowly release, repeat 3 times, then slowly introduce CO2 to stabilize to 0.2MPa, heat to 50°C, stir to react for 2h, filter, wash and dry to obtain modified pulp;

[0083] S3, add 120g of modified pulp into a fiber separator, then add 0.4g of sizing agent and 0.4g of papermaking filler to disperse, then transfer to a sheet making machine, add water to adjust the screen concentration to 0.1wt%, stir and disperse, let stand for 10s, filter and dehydrate, mechanically press, and dry to obtain modified corrugated paper;

[0084] The papermaking filler is a mixture of talcum powder and calcium carbonate in a mass ratio of 1:1, and the sizing agent is a mixture of saponified rosin glue, cationic rosin glue and dispersed rosin glue in a mass ratio of 1:1:1.

[0085] Comparative Example 3

[0086] A method for preparing modified corrugated paper comprises the following steps:

[0087] S1. Put 900g of waste corrugated paper into a pulping tank, add 2000mL of deionized water until the paper is pulped, stir for 1h, then add 5mL of 0.2vt% PAM-LB-3 anionic polyacrylamide, continue stirring for 0.5h, filter and sieve to remove impurities, and obtain pulp after washing;

[0088] S2, add 15g of isatoic anhydride, 10g of tris(hydroxymethyl)aminomethane and 170mL of ethyl acetate into reactor A, stir evenly, heat to 70-80°C, keep warm for 12h, filter, wash and dry to obtain intermediate 1;

[0089] S3, add 150g of pulp, 140mL of dimethyl sulfoxide and 20g of 1,8-diazabicycloundec-7-ene to reactor C, stir evenly, slowly introduce CO2 to 1MPa, slowly release, repeat 3 times, then slowly introduce CO2 to stabilize to 0.2MPa, heat to 50°C to obtain intermediate three mixed liquid, ultrasonically disperse the intermediate three mixed liquid and 20g of intermediate one, heat to 40°C, stir to react for 2h, filter, wash and dry to obtain modified pulp;

[0090] S4, add 120g of modified pulp into a fiber separator, then add 0.4g of sizing agent and 0.4g of papermaking filler to disperse, then transfer to a sheet making machine, add water to adjust the screen concentration to 0.1wt%, stir and disperse, let stand for 10s, filter and dehydrate, mechanically press, and dry to obtain modified corrugated paper;

[0091] The papermaking filler is a mixture of talcum powder and calcium carbonate in a mass ratio of 1:1, and the sizing agent is a mixture of saponified rosin glue, cationic rosin glue and dispersed rosin glue in a mass ratio of 1:1:1.

[0092] Comparative Example 4

[0093] Compared with Example 7, the modified corn starch glue prepared in Example 1 used therein was replaced by an equal amount of the modified corn starch glue prepared in Comparative Example 1, and the remaining raw materials and preparation process were the same as in Example 7.

[0094] Comparative Example 5

[0095] Compared with Example 7, the modified corrugated paper prepared in Example 4 used therein is replaced by an equal amount of the modified corrugated paper prepared in Comparative Example 2, and the remaining raw materials and preparation process are the same as in Example 7.

[0096] Comparative Example 6

[0097] Compared with Example 7, the modified corrugated paper prepared in Example 4 used therein is replaced by an equal amount of the modified corrugated paper prepared in Comparative Example 3, and the remaining raw materials and preparation process are the same as in Example 7.

[0098] Comparative Example 7

[0099] Compared with Example 7, the modified corn starch glue prepared in Example 1 used therein is replaced by an equal amount of the modified corn starch glue prepared in Comparative Example 1, and the modified corrugated paper prepared in Example 4 used therein is replaced by an equal amount of the modified corrugated paper prepared in Comparative Example 2, and the remaining raw materials and preparation process are the same as in Example 7.

[0100] Comparative Example 8

[0101] Compared with Example 7, the modified corn starch glue prepared in Example 1 used therein is replaced by an equal amount of the modified corn starch glue prepared in Comparative Example 1, and the modified corrugated paper prepared in Example 4 used therein is replaced by an equal amount of the modified corrugated paper prepared in Comparative Example 3, and the remaining raw materials and preparation process are the same as in Example 7.

[0102] Performance Testing

[0103] (1) Adhesion strength

[0104] The test was conducted according to GB / T6548-2011 "Determination of Adhesion Strength of Corrugated Cardboard". Before the test, the corrugated cardboard was placed in a constant temperature and humidity test chamber for 12 hours. The constant temperature and humidity test chamber was set at 35°C, 40% RH and 80% RH. The test results are shown in Table 1.

[0105] (2) Edge compression strength

[0106] The side compression strength of the sample was tested with reference to GB / T1454-1988, and the sample was pressed at a speed of 10 mm / min. The test results are shown in Table 1. (3) Burst strength

[0107] The bursting strength of the samples was tested according to GB / T6545-1998. The test results are shown in Table 1.

[0108] Table 1: Performance test of corrugated paper of Examples 7-9 and Comparative Examples 4-8

[0109]

[0110]

[0111] As shown in Table 1, the corrugated paperboards prepared in Examples 7-9 have more excellent toughness, more stable bonding performance and stronger supporting strength.

[0112] The embodiments of the present invention are described in detail above, but the contents described are only preferred embodiments of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A production process for green, recyclable, high-toughness corrugated paperboard, characterized in that: The following steps are involved: (1) uniformly coating the surface of the modified corrugated paper with modified corn starch glue by a glue roller; (2) laminating the modified corrugated paper after sizing, drying it in a drying box, and sending it to a corrugator for corrugation to obtain corrugated paper; (3) The two sides of the corrugated paper are coated with styrene acrylic emulsion and pressed with the surface paper to obtain the corrugated paperboard; The preparation method of modified corrugated paper comprises the following steps: S1, add 15-20g of isatoic anhydride, 10-15g of tris(hydroxymethyl)aminomethane and 170-220mL of ethyl acetate into reactor A, stir evenly, heat to 70-80°C, keep warm for 12h, filter, wash and dry to obtain intermediate 1; S2, add intermediate 1, 3-mercapto-1,2-propylene glycol and deionized water into reactor B, stir evenly, add 1-(2-hydroxyethyl)-3-methylimidazole chloride, heat to 70-80°C, and keep the temperature for 1-2h to obtain intermediate 2; Intermediate 1: the mass ratio of 3-mercapto-1,2-propylene glycol: deionized water: 1-(2-hydroxyethyl)-3-methylimidazole chloride is 20-30: 20-30: 100-150: 20-25; S3, add 150-200g of pulp, 140-220mL of dimethyl sulfoxide and 20-30g of 1,8-diazabicycloundec-7-ene to reactor C, stir evenly, slowly introduce CO2 to 1MPa, slowly release, repeat 3 times, then slowly introduce CO2 to stabilize to 0.2MPa, heat to 50°C to obtain intermediate three mixed liquid, ultrasonically disperse the intermediate three mixed liquid and 20-30g of intermediate two, heat to 40°C, stir to react for 2h, filter, wash and dry to obtain modified pulp; S4, add 120-180g of modified pulp into a fiber separator, then add 0.4-0.6g of sizing agent and 0.4-0.6g of papermaking filler for dispersion, transfer to a sheet making machine, add water to adjust the screen concentration to 0.1%wt, let stand for 10s, filter and dehydrate, mechanically press, and dry to obtain modified corrugated paper; The preparation method of modified corn starch glue comprises the following steps: adding corn starch and deionized water into a reaction kettle D, heating to 30-40° C., mechanically stirring for 5-10 min, cooling to room temperature, dropping a saturated sodium carbonate solution to adjust the pH to 9, adding 4-(maleimido)phenyl isocyanate and a 10 wt % borax aqueous solution, continuing to stir and react for 1-2 h, washing and drying to obtain the modified corn starch glue; The usage ratio of corn starch, deionized water, 4-(maleimido)phenyl isocyanate and 10wt% borax aqueous solution is 0.5-1mol:50-60mL:1-2mol:0.4-0.6mL.

2. A green recyclable high-toughness corrugated paperboard produced by the production process of a green recyclable high-toughness corrugated paperboard according to claim 1, characterized in that: The invention comprises corrugated paper and face paper adhered to both sides of the corrugated paper. The corrugated paper is composed of multiple layers of modified corrugated paper and an adhesive layer coated on the surface of the modified corrugated paper. The adhesive layer is obtained by uniformly coating the surface of the modified corrugated paper with modified corn starch glue by a glue coating roller.

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