A tensile and wear-resistant washed kraft paper and its preparation process

Abstract

The present invention discloses a tensile and wear-resistant washed kraft paper and its preparation process, which relates to the technical field of kraft paper. The process includes the following steps: Step 1: Add color paste, waterborne acrylic resin, preservative, reinforcing agent, softening agent, curing agent, and waterproofing agent into a solvent in sequence and stir evenly to obtain a sizing slurry; Step 2: Coat the sizing slurry on the base paper, and successively perform extrusion, ultraviolet light irradiation, first drying, ironing, and second drying to obtain the tensile and wear-resistant washed kraft paper. In this application, by preparing specific reinforcing agent and waterproofing agent and introducing them into the sizing slurry for sizing, the interfacial action between the sizing slurry and the base paper is effectively improved, thereby improving the tensile and wear resistance of the washed kraft paper while enhancing the flame retardant performance; it can achieve the purpose of replacing plastic, leather, and cloth with paper.

Description

Technical Field

[0001] The invention relates to the technical field of kraft paper, in particular to a tensile and wear-resistant washed kraft paper and a preparation process thereof. Background Art

[0002] Washed kraft paper, also known as high-wet-strength imitation leather paper, is an environmentally friendly material made from natural fiber pulp. It has a texture close to leather and is widely used in packaging fields such as handbags, clothing tags, and notebook covers.

[0003] In general processes, in order to improve the tensile and wear resistance of washed kraft paper, a reinforcement layer is usually formed on the surface of the base paper through a sizing process, which effectively improves the comprehensive properties of washed kraft paper, such as toughness and strength. However, in the prior art, the sizing liquid is usually a substance with high viscosity such as polyvinyl alcohol, which has high viscosity and poor coating performance, and has limited improvement in the tensile properties of washed kraft paper; at the same time, functional additives such as flame retardants are usually introduced into the sizing liquid, but the introduction of various substances will cause compatibility and dispersion uniformity problems, resulting in the formation of a discontinuous film, which makes the wear resistance of washed kraft paper poor.

[0004] In summary, in order to solve the above problems, a tensile and wear-resistant washed kraft paper and its preparation process are prepared, which are of great significance. Summary of the invention

[0005] The object of the present invention is to provide a tensile and wear-resistant washed kraft paper and a preparation process thereof, so as to solve the problems raised in the above background technology.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] A preparation process of tensile wear-resistant washed kraft paper, comprising the following steps:

[0008] Step 1: Add color paste, water-based acrylic resin, preservative, enhancer, softener, curing agent and waterproofing agent to the solvent in sequence and stir evenly to obtain a sizing slurry;

[0009] Step 2: Apply the sizing slurry on the base paper, and sequentially perform extrusion, ultraviolet light irradiation, first drying, ironing, and second drying to obtain tensile and wear-resistant washed kraft paper.

[0010] Among them, the extrusion pressure is 8 kg; the first drying temperature is 60-160°C; the ironing temperature is 70-170°C, and the second drying temperature is 80-180°C.

[0011] More optimally, the raw materials of the base paper include the following components: by weight, 85-95 parts of coniferous wood pulp, 5-15 parts of cotton pulp, 1-5 parts of acid-modified cellulose, and 1-5 parts of mercapto chitosan.

[0012] Preferably, the preparation method of the acid-modified cellulose is as follows: Add bacterial cellulose, thiomalic acid, and stannous chloride to deionized water and stir evenly. Keep it at a constant temperature of 80 - 100 °C for 36 hours, wash and dry to obtain the acid-modified cellulose;

[0013] Among them, the raw materials of the acid-modified cellulose include the following components: by weight, 1 - 2 parts of bacterial cellulose, 3 - 6 parts of thiomalic acid, 0.001 - 0.002 parts of stannous chloride, and 100 - 110 parts of deionized water.

[0014] Preferably, the sizing slurry includes the following raw materials by mass parts: by weight, 0.5 - 10 parts of color paste, 20 - 50 parts of waterborne acrylic resin, 0.1 - 5 parts of preservative, 0.1 - 10 parts of reinforcing agent, 0.2 - 8 parts of softening agent, 0.1 - 5 parts of curing agent, 0.2 - 10 parts of waterproofing agent, and 2 - 30 parts of solvent.

[0015] Preferably, the sizing slurry includes the following raw materials by mass parts: by weight, 2 - 3 parts of color paste, 35 - 40 parts of waterborne acrylic resin, 1 - 2 parts of preservative, 10 - 15 parts of reinforcing agent, 3 - 4 parts of softening agent, 1 - 2 parts of curing agent, 4 - 6 parts of waterproofing agent, and 20 - 30 parts of solvent.

[0016] Preferably, the reinforcing agent is an allyl organic framework, and the specific preparation method is as follows:

[0017] (1) Add cyclodextrin and potassium hydroxide to deionized water in sequence and stir evenly to obtain a precursor solution; Use methanol vapor to perform vapor diffusion on the precursor solution at 50 - 52 °C for 10 - 12 hours; Then add polyethylene glycol and stir at room temperature for 10 - 12 hours, separate, wash, and dry to obtain the cyclodextrin organic framework;

[0018] (2) Add the cyclodextrin organic framework to deionized water, add sodium hydroxide to adjust the pH to 9.5 - 10; Dropwise add 2-chloroacetamide and stir at 40 - 45 °C for 4 - 5 hours; Raise the temperature to 90 - 95 °C and stir for 10 - 15 minutes, cool and wash to neutral to obtain the amino-functionalized organic framework;

[0019] (3) Add the amino-functionalized organic framework to deionized water, add 2-methylacrolein, and stir at a temperature of 50 - 55 °C for 1 - 2 hours, wash and dry to obtain the allyl organic framework.

[0020] Preferably, the raw materials of the cyclodextrin organic framework include the following components in parts by weight: 12-13 parts of cyclodextrin, 4-5 parts of potassium hydroxide, 180-200 parts of deionized water, and 0.5-0.8 parts of polyethylene glycol; in the raw materials of the aminated organic framework, the mass ratio of the cyclodextrin organic framework to 2-chloroacetamide is 1:0.8-1; in the raw materials of the allyl-modified organic framework, the mass ratio of the aminated organic framework to 2-methylacrolein is 1:0.4-0.5.

[0021] Preferably, the waterproofing agent is mercapto chitosan, and its preparation method is as follows: under a nitrogen atmosphere, chitosan is added to deionized water and stirred evenly, 1-ethyl-(3-dimethylaminopropyl)-3-carbodiimide hydrochloride, acetylcysteine, mercapto-triglycol-carboxylic acid, and n-decanoic acid are added, and under dark light, the mixture is stirred and reacted for 24 hours, purified and freeze-dried to obtain mercapto chitosan.

[0022] Preferably, the raw materials of the mercapto chitosan include the following components in parts by weight: 10 parts of chitosan, 7-8 parts of 1-ethyl-(3-dimethylaminopropyl)-3-carbodiimide hydrochloride, 4-5 parts of acetylcysteine, 3-5 parts of mercapto-triglycol-carboxylic acid, and 8-12 parts of n-decanoic acid.

[0023] Preferably, the curing agent includes organic peroxide curing agents and photoinitiators; the solvent includes 2,4,7,9-tetramethyl-5-decyne-4,7-diol and deionized water with a mass ratio of 1:4. The softener is amino polysiloxane.

[0024] Preferably, the tensile and wear-resistant washed kraft paper is prepared by a preparation process of a tensile and wear-resistant washed kraft paper, and the basis weight of the base paper is 20-500 g / m 2 ; after sizing with the sizing slurry, the basis weight of the tensile and wear-resistant washed kraft paper is 26-600 g / m 2 .

[0025] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0026] (1) The tensile and wear-resistant washed kraft paper prepared in this application can achieve the purpose of replacing plastics, leathers, and cloths with paper.

[0027] (2) In this application, acid-modified cellulose is introduced into the base paper, effectively improving the tensile strength of the base paper, and at the same time improving the sizing property of the subsequent sizing slurry, enhancing the interfacial interaction, and utilizing the dispersion crosslinking property of the reinforcing agent in the sizing slurry to comprehensively improve the tensile and wear resistance of the washed kraft paper.

[0028] Among them, the acid-modified cellulose is obtained by modifying bacterial cellulose with thiomalic acid; bacterial cellulose is a substance with high crystallinity, and its introduction can be evenly bridged between fibers to play a strengthening role; it can effectively improve the tensile strength and elastic modulus of the base paper. Moreover, it can increase the smoothness of the base paper and improve the coating and film-forming properties of the subsequent sizing slurry. The modification with thiomalic acid can, firstly, improve the softness of the paper; secondly, the modification of the acid generates ester groups, which can improve the water resistance; thirdly, it contains mercapto groups, which are beneficial to the cross-linking with the subsequent sizing slurry, promoting the sizing performance and improving the comprehensive performance of the water-washed kraft paper.

[0029] In the (3) solution, aqueous acrylic resin is used as the main sizing raw material, and a specifically prepared allyl organic framework is introduced as a reinforcing agent, and a specifically prepared mercapto chitosan is introduced as a waterproof agent. On the basis of effectively ensuring cross-linking and film-forming properties, the flame retardancy, tensile strength and wear resistance are enhanced.

[0030] Among them, the allyl organic framework is based on cyclodextrin. First, cyclodextrin organic framework is prepared by using methanol vapor method with it and potassium hydroxide, then successively subjected to amino modification with 2-chloroacetamide, and then grafted with allyl by reacting 2-methylacrolein with amino group to obtain the allyl organic framework. Firstly, the cyclodextrin framework is a framework material with a special structure, having excellent thermal stability and flame retardancy. Cyclodextrin is a friendly char-forming layer, isolating oxygen and heat, inhibiting combustion, and the contained potassium ions can promote the carbon layer and inhibit the flame; it can cooperate with a softener (hydroxy silicone oil) and a waterproof agent (mercapto chitosan) for flame retardancy. Secondly, due to the subsequent grafting, it contains allyl groups, which can effectively react with the aqueous acrylic resin to generate cross-linking properties and improve its uniform cross-linking; and the grafted chain segments generated by the subsequent two-step grafting effectively provide cross-linking toughness, inhibit the generation of stress cracks during drying, effectively improve the surface film-forming properties, and improve the tensile performance; thirdly, the allyl organic framework is an organic-inorganic hybrid material, and it has reactive groups that can promote the cross-linking degree, thus improving the wear resistance of the water-washed kraft paper.

[0031] Among them, mercapto chitosan is obtained by grafting acetylcysteine, mercapto-triethylene glycol-carboxylic acid, and n-decanoic acid as grafting segments based on chitosan by using the activation property of 1-ethyl-(3-dimethylaminopropyl)-carbodiimide hydrochloride; chitosan is a material with excellent film-forming properties, and the groups contained in its molecular chain can improve the binding force between paper fibers and enhance the tensile and abrasion resistance of the paper. The ammonia and sulfur elements it contains can produce synergistic flame retardancy; the triethylene glycol it contains improves the affinity with the paper and enhances the softness; while the higher grafting amount of n-decanoic acid, due to the presence of long-chain alkyl groups, effectively improves the waterproofness of kraft paper. It should be noted that in order to promote its dispersion uniformity, 2,4,7,9-tetramethyl-5-decyne-4,7-diol is introduced into the solvent to promote the dispersion and film-forming properties, improve the waterproofness, and ensure the tensile and abrasion resistance of kraft paper.

[0032] In summary, by preparing specific reinforcing agents and waterproof agents and introducing them into the sizing slurry for sizing, the interfacial interaction between the sizing slurry and the base paper is effectively improved, thereby improving the comprehensive performance of the washed kraft paper. Specific Embodiments

[0033] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0034] It should be noted that the following parts are by weight, and there are no special restrictions on the purchase manufacturers of all the raw materials involved in the present invention. Exemplarily, in the following embodiments, the model of the aqueous acrylic resin is Soluryl-90; the model of the hydroxy silicone oil is hydroxy silicone oil 209; the brand of the bacterial cellulose is Gardel; the degree of deacetylation of the chitosan is ≥85%; the brand of the cyclodextrin is Prolovo; and other raw materials are all commercially available.

[0035] Example 1: A preparation process for a tensile and abrasion-resistant washed kraft paper, comprising the following steps:

[0036] Pre-preparation: Add 1 part of bacterial cellulose, 3.2 parts of thiomalic acid, and 0.001 part of stannous chloride to 100 parts of deionized water, stir evenly, keep it at a constant temperature of 100 °C for 36 hours, wash and dry to obtain acid-modified cellulose;

[0037] The reinforcing agent is an allyl organic framework, and its preparation method is as follows: (1) Add 12 cyclodextrins and 4.3 parts of potassium hydroxide to 180 parts of deionized water in sequence and stir evenly to obtain a precursor solution; use methanol vapor to perform vapor diffusion on the precursor solution at 50 °C for 12 hours; then add 0.6 part of polyethylene glycol-20000 and stir at room temperature for 12 hours, separate, wash, and dry to obtain a cyclodextrin organic framework; (2) Add 10 parts of the cyclodextrin organic framework to 100 parts of deionized water, add sodium hydroxide to adjust the pH to 9.8; dropwise add 9 parts of 2-chloroacetamide and stir at 45 for 4 hours; raise the temperature to 90 °C and stir for 15 minutes, cool, wash until neutral to obtain an amino-functionalized organic framework; (3) Add 10 parts of the amino-functionalized organic framework to 50 parts of deionized water, add 4.5 parts of 2-methylacrolein, stir at a temperature of 55 °C for 1.5 hours, wash, and dry to obtain an allyl organic framework;

[0038] The waterproofing agent is mercaptochitosan, and its preparation method is as follows: Under a nitrogen atmosphere, add 10 parts of chitosan to 80 parts of deionized water and stir evenly, add 7.8 parts of 1-ethyl(3-dimethylaminopropyl)-3-carbodiimide hydrochloride, 5 parts of acetylcysteine, 4 parts of mercapto-triethylene glycol-carboxylic acid, and 10 parts of n-decanoic acid, and stir and react for 24 hours in the dark, purify, and freeze-dry to obtain mercaptochitosan;

[0039] Step 1: Add 2.5 parts of color paste (iron oxide color paste), 40 parts of waterborne acrylic resin, 1.5 parts of preservative (dimethyl dibenzoyl imide), 8 parts of reinforcing agent, 3.5 parts of softener (hydroxy silicone oil), 1.5 parts of curing agent (ammonium persulfate, tert-butyl hydroperoxide, azobisisobutyronitrile with a mass ratio of 0.5:0.8:0.2), and 5 parts of waterproofing agent to 25 parts of solvent (tetramethyl decynediol and deionized water with a mass ratio of 1:4) in sequence, and stir evenly at a speed of 1.5 S / turn for 20 minutes to obtain a sizing slurry;

[0040] Step 2: (1) Mix 92 parts of softwood pulp, 8 parts of cotton pulp, 4 parts of acid-modified cellulose, and 4 parts of mercaptochitosan for beating, and form a paper web on a paper machine to obtain a base paper with a basis weight of 300 g / m 2 ; (2) Coat the sizing slurry on the base paper, perform extrusion in sequence, with an extrusion pressure of 8 kg, ultraviolet light irradiation at 254 nm for 15 minutes, first drying at 120 °C, ironing at 150 °C, and second drying at 180 °C to obtain a tensile, wear-resistant, and washable kraft paper with a basis weight of 400 g / m 2

[0041] Example 2: A preparation process for a tensile, wear-resistant, and washable kraft paper, comprising the following steps:

[0042] ​Pre-preparation: Add 1 part of bacterial cellulose, 3.2 parts of thiomalic acid, and 0.001 part of stannous chloride to 100 parts of deionized water, stir evenly, place it at 100 °C for constant temperature preservation for 36 hours, wash and dry to obtain acid-modified cellulose;

[0043] The reinforcing agent is allyl organic framework, and the preparation method is as follows: (1) Add 12 cyclodextrins and 4.3 parts of potassium hydroxide to 180 parts of deionized water in sequence, stir evenly to obtain a precursor solution; use methanol vapor to carry out vapor diffusion on the precursor solution at 50 °C for 12 hours; then add 0.6 part of polyethylene glycol-20000 and stir at room temperature for 12 hours, separate, wash and dry to obtain cyclodextrin organic framework; (2) Add 10 parts of cyclodextrin organic framework to 100 parts of deionized water, add sodium hydroxide to adjust the pH to 9.8; dropwise add 9 parts of 2-chloroacetamide and stir at 45 °C for 4 hours; raise the temperature to 90 °C and stir for 15 minutes, cool and wash to neutral to obtain amino-functionalized organic framework; (3) Add 10 parts of amino-functionalized organic framework to 50 parts of deionized water, add 4.5 parts of 2-methylacrolein, stir at 55 °C for 1.5 hours, wash and dry to obtain allyl organic framework;

[0044] The waterproofing agent is mercaptochitosan, and the preparation method is as follows: Under a nitrogen atmosphere, add 10 parts of chitosan to 80 parts of deionized water, stir evenly, add 7.8 parts of 1-ethyl(3-dimethylaminopropyl)-3-carbodiimide hydrochloride, 5 parts of acetylcysteine, 4 parts of mercapto-triethylene glycol-carboxylic acid, and 10 parts of n-decanoic acid, and stir and react for 24 hours in the dark, purify and freeze-dry to obtain mercaptochitosan;

[0045] Step 1: Add 2 parts of color paste (iron oxide color paste), 35 parts of waterborne acrylic resin, 1 part of preservative (dimethyl dibenzoyl imide), 10 parts of reinforcing agent, 3 parts of softener (hydroxy silicone oil), 1.5 parts of curing agent (ammonium persulfate, tert-butyl hydroperoxide, azodiisobutyronitrile with a mass ratio of 0.5:0.8:0.2), and 4 parts of waterproofing agent to 20 parts of solvent (tetramethyl decynediol and deionized water with a mass ratio of 1:4) in sequence, and stir evenly at a speed of 1.5S / turn for 20 minutes to obtain sizing slurry;

[0046] Step 2: (1) Mix 95 parts of softwood pulp, 5 parts of cotton pulp, 5 parts of acid-modified cellulose, and 3 parts of mercaptochitosan, beat them into pulp, and form a paper web by papermaking to obtain a base paper with a basis weight of 300 g / m 2 ; (2) Coat the sizing slurry on the base paper, and carry out extrusion in sequence, the extrusion pressure is 8 kg, ultraviolet light irradiation at 254 nm for 15 minutes, first drying at 120 °C, ironing at 150 °C, and second drying at 180 °C to obtain a tensile, wear-resistant and washable kraft paper with a basis weight of 400 g / m 2 ​

[0047] Example 3: A preparation process of tensile and wear-resistant washed kraft paper, comprising the following steps:

[0048] Pre-preparation: Add 1 part of bacterial cellulose, 3.2 parts of thiomalic acid, and 0.001 part of stannous chloride to 100 parts of deionized water, stir evenly, keep it at a constant temperature of 100 °C for 36 hours, wash and dry to obtain acid-modified cellulose;

[0049] The reinforcing agent is allyl organic framework, and the preparation method is as follows: (1) Add 12 cyclodextrin and 4.3 parts of potassium hydroxide to 180 parts of deionized water in sequence, stir evenly to obtain a precursor solution; use methanol vapor to carry out vapor diffusion on the precursor solution at 50 °C for 12 hours; then add 0.6 part of polyethylene glycol-20000 and stir at room temperature for 12 hours, separate, wash and dry to obtain cyclodextrin organic framework; (2) Add 10 parts of cyclodextrin organic framework to 100 parts of deionized water, add sodium hydroxide to adjust the pH to 9.8; dropwise add 9 parts of 2-chloroacetamide, stir at 45 for 4 hours; raise the temperature to 90 °C and stir for 15 minutes, cool and wash to neutrality to obtain amino-functionalized organic framework; (3) Add 10 parts of amino-functionalized organic framework to 50 parts of deionized water, add 4.5 parts of 2-methylacrolein, stir at a temperature of 55 °C for 1.5 hours, wash and dry to obtain allyl organic framework;

[0050] The waterproof agent is mercapto chitosan, and the preparation method is as follows: Under a nitrogen atmosphere, add 10 parts of chitosan to 80 parts of deionized water, stir evenly, add 7.8 parts of 1-ethyl-(3-dimethylaminopropyl)-3-carbodiimide hydrochloride, 5 parts of acetylcysteine, 4 parts of mercapto-triglycol-carboxylic acid, and 10 parts of n-decanoic acid, stir and react for 24 hours in the dark, purify and freeze-dry to obtain mercapto chitosan;

[0051] Step 1: Add 3 parts of color paste (iron oxide color paste), 50 parts of waterborne acrylic resin, 2 parts of preservative (dimethyl dibenzoyl imide), 5 parts of reinforcing agent, 4 parts of softener (hydroxy silicone oil), 1.5 parts of curing agent (ammonium persulfate, tert-butyl hydroperoxide, azobisisobutyronitrile with a mass ratio of 0.5:0.8:0.2), and 6 parts of waterproof agent to 30 parts of solvent (tetramethyl decynediol and deionized water with a mass ratio of 1:4) in sequence, stir evenly at a speed of 1.5 S / turn for 20 minutes to obtain sizing slurry;

[0052] Step 2: (1) Mix 85 parts of softwood pulp, 15 parts of cotton pulp, 3 parts of acid-modified cellulose, and 5 parts of mercapto chitosan for beating, and form a paper web by papermaking to obtain a basis weight of 300 g / m 2Base paper; (2) Coating the sizing slurry on the base paper, followed by extrusion, with an extrusion pressure of 8 kg, ultraviolet irradiation for 15 minutes under a 254 nm ultraviolet lamp, first drying at 120 °C, ironing at 150 °C, and second drying at 180 °C, to obtain a basis weight of 400 g / m 2 Tensile and abrasion-resistant washable kraft paper.

[0053] Comparative Example 1: Acid-modified cellulose is not introduced into the base paper; the rest is the same as in Example 1; the specific differences are as follows:

[0054] Step 2: (1) Mixing 92 parts of softwood pulp, 8 parts of cotton pulp, and 4 parts of mercaptochitosan for beating, forming a paper web on a paper machine, to obtain a base paper with a basis weight of 300 g / m 2 Base paper; (2) Coating the sizing slurry on the base paper, followed by extrusion, with an extrusion pressure of 8 kg, ultraviolet irradiation for 15 minutes under a 254 nm ultraviolet lamp, first drying at 120 °C, ironing at 150 °C, and second drying at 180 °C, to obtain a basis weight of 400 g / m 2 Tensile and abrasion-resistant washable kraft paper.

[0055] Comparative Example 2: In the sizing slurry, the waterproofing agent is replaced with decyl chitosan; the rest is the same as in Example 1; the specific differences are as follows:

[0056] The waterproofing agent is decyl chitosan, and the preparation method is as follows: Under a nitrogen atmosphere, 10 parts of chitosan are added to 80 parts of deionized water and stirred evenly, then 7.8 parts of 1-ethyl(3-dimethylaminopropyl)-3-carbodiimide hydrochloride and 10 parts of n-decanoic acid are added, and the mixture is stirred and reacted for 24 hours in the dark, purified and freeze-dried to obtain decyl chitosan.

[0057] Comparative Example 3: In the sizing slurry, cyclodextrin organic framework is directly introduced as a reinforcing agent; the rest is the same as in Example 1; the specific differences are as follows:

[0058] Step 1: Adding 2.5 parts of color paste (iron oxide color paste), 40 parts of waterborne acrylic resin, 1.5 parts of preservative (dimethyl dibenzoyl imide), 8 parts of cyclodextrin organic framework, 3.5 parts of softening agent (hydroxy silicone oil), 1.5 parts of curing agent (ammonium persulfate, tert-butyl hydroperoxide, azobisisobutyronitrile with a mass ratio of 0.5:0.8:0.2), and 5 parts of waterproofing agent into 25 parts of solvent (tetramethyl decynediol and deionized water with a mass ratio of 1:4) in sequence, and stirring evenly for 20 minutes at a speed of 1.5 S / turn to obtain the sizing slurry.

[0059] Comparative Example 4: In the sizing slurry, the amount of the reinforcing agent is increased to 20 parts; the rest is the same as in Example 1; the specific differences are as follows:

[0060] Step 1: Add 2.5 parts of color paste (iron oxide color paste), 40 parts of waterborne acrylic resin, 1.5 parts of preservative (dimethyl dibenzoyl imide), 20 parts of reinforcing agent, 3.5 parts of softener (hydroxyl silicone oil), 1.5 parts of curing agent (ammonium persulfate, tert-butyl hydroperoxide, azodiisobutyronitrile with a mass ratio of 0.5:0.8:0.2), and 5 parts of waterproof agent into 25 parts of solvent (tetramethyl decynediol and deionized water with a mass ratio of 1:4) in sequence, and stir evenly for 20 minutes at a speed of 1.5S / turn to obtain the sizing slurry.

[0061] Performance Test 1: For the tensile and wear-resistant washed kraft paper prepared in the examples and comparative examples, in accordance with GB / T - 12914 "Determination of Tensile Strength of Paper and Board - Constant Rate Tensile Method (20mm / min)"; the sample width is 20mm and the length is 250mm, and the mechanical properties are detected at a tensile strength of 20mm / min; use a comprehensive surface property tester to test the wear rate of 4.5×4.5mm 2 samples.

[0062] Sample Transverse Tensile Force kg Longitudinal Tensile Force kg Wear Rate × 10-4mm3 / J Example 1 10.20 21.84 2.43 Example 2 9.80 21.03 2.54 Example 3 9.85 21.11 2.50 Comparative Example 1 9.38 20.57 2.56 Comparative Example 2 9.21 19.85 2.75 Comparative Example 3 8.96 19.38 2.82 Comparative Example 4 9.50 20.46 2.62

[0063] Conclusion: It can be seen from the data in the above table that the washed kraft paper with high tensile strength and wear resistance is prepared in this application. It can be seen from the data of Comparative Examples 1 - 4: the importance of the process and content of specifically prepared acid-modified fibers, mercapto chitosan, and allyl organic frameworks in kraft paper; in Comparative Example 1, due to the absence of acid-modified cellulose, the mechanical properties and others decreased; in Comparative Example 2, due to the replacement of the waterproof agent with decyl chitosan, the interfacial film-forming property decreased, resulting in a decrease in related properties; in Comparative Example 3, due to the cyclodextrin organic framework, the crosslinking property decreased, resulting in a decrease in performance; in Comparative Example 4, due to the increase in the content of the reinforcing agent, the strength decreased.

[0064] Performance Test 2: Cut the tensile and wear-resistant washed kraft paper of Example 1 into samples of 6.5×100mm 2 and use a digital display oxygen index meter to conduct a limiting oxygen index test on it.

[0065] Result: The LOI value of Example 1 is 26.8%, indicating that the prepared tensile and wear-resistant washed kraft paper has flame retardancy.

[0066] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A process for preparing tensile wear-resistant washed kraft paper, characterized in that: The following steps are involved: Step 1: Add color paste, water-based acrylic resin, preservative, enhancer, softener, curing agent and waterproofing agent to the solvent in sequence and stir evenly to obtain a sizing slurry; Step 2: coating the sizing slurry on the base paper, and sequentially performing extrusion, ultraviolet light, first drying, ironing, and second drying to obtain tensile and wear-resistant washed kraft paper; The reinforcing agent is a propylene-based organic framework, and the specific preparation method is: (1) Cyclodextrin and potassium hydroxide are sequentially added to deionized water and stirred evenly to obtain a precursor solution; the precursor solution is subjected to vapor diffusion at 50-52° C. for 10-12 hours using methanol vapor; polyethylene glycol is then added and stirred at room temperature for 10-12 hours, and the mixture is separated, washed, and dried to obtain a cyclodextrin organic framework; (2) Add the cyclodextrin organic framework to deionized water, add sodium hydroxide to adjust the pH to 9.5-10; add 2-chloroacetamide dropwise, stir at 40-45°C for 4-5 hours; heat to 90-95°C, stir for 10-15 minutes, cool, and wash to neutrality to obtain an amino organic framework; (3) adding the amino organic framework to deionized water, adding 2-methylacrolein, stirring at a temperature of 50-55° C. for 1-2 hours, washing, and drying to obtain an acryl organic framework; The raw materials of the base paper include the following components: by weight, 85-95 parts of conifer pulp, 5-15 parts of cotton pulp, 1-5 parts of acid-modified cellulose, and 1-5 parts of mercapto chitosan.

2. The process for preparing the tensile wear-resistant washed kraft paper according to claim 1, characterized in that: The preparation method of the acid-modified cellulose is as follows: bacterial cellulose, thiomalic acid and tin chloride are added to deionized water and stirred evenly, the deionized water is kept at a constant temperature of 80-100° C. for 36 hours, washed and dried to obtain the acid-modified cellulose; The raw materials of acid-modified cellulose include the following components: by weight, 1-2 parts of bacterial cellulose, 3-6 parts of thiomalic acid, 0.001-0.002 parts of tin chloride, and 100-110 parts of deionized water.

3. The process for preparing the tensile wear-resistant washed kraft paper according to claim 1, characterized in that: The sizing slurry comprises the following raw materials in parts by weight: by weight, 0.5 to 10 parts of color paste, 20 to 50 parts of water-based acrylic resin, 0.1 to 5 parts of preservative, 0.1 to 10 parts of reinforcing agent, 0.2 to 8 parts of softener, 0.1 to 5 parts of curing agent, 0.2 to 10 parts of waterproofing agent, and 2 to 30 parts of solvent.

4. The process for preparing the tensile wear-resistant washed kraft paper according to claim 1, characterized in that: The raw materials of the cyclodextrin organic framework include the following components, measured by weight: 12 to 13 parts of cyclodextrin, 4 to 5 parts of potassium hydroxide, 180 to 200 parts of deionized water, and 0.5 to 0.8 parts of polyethylene glycol; in the raw materials of the amino organic framework, the mass ratio of the cyclodextrin organic framework to 2-chloroacetamide is 1:0.8 to 1; in the raw materials of the acryl organic framework, the mass ratio of the amino organic framework to 2-methylacrolein is 1:0.4 to 0.

5.

5. The process for preparing the tensile wear-resistant washed kraft paper according to claim 1, characterized in that: The waterproofing agent is mercapto chitosan, and the preparation method thereof is as follows: under a nitrogen atmosphere, chitosan is added to deionized water and stirred evenly, 1-ethyl (3-dimethylaminopropyl) -3-carbodiimide hydrochloride, acetylcysteine, mercapto-triethylene glycol-carboxylic acid, and n-decanoic acid are added, stirred and reacted for 24 hours in a dark environment, purified, and freeze-dried to obtain mercapto chitosan.

6. The process for preparing the tensile wear-resistant washed kraft paper according to claim 5, characterized in that: The raw materials of the mercapto chitosan include the following components, by weight: 10 parts of chitosan, 7-8 parts of 1-ethyl (3-dimethylaminopropyl) -3-carbodiimide hydrochloride, 4-5 parts of acetylcysteine, 3-5 parts of mercapto-triethylene glycol-carboxylic acid, and 8-12 parts of n-decanoic acid.

7. The process for preparing the tensile wear-resistant washed kraft paper according to claim 1, characterized in that: The curing agent includes an organic peroxide curing agent and a photoinitiator; and the solvent includes tetramethyldecynediol and deionized water in a mass ratio of 1:

4.

8. The tensile-wear-resistant washed kraft paper prepared by the process for preparing the tensile-wear-resistant washed kraft paper according to any one of claims 1 to 7 is characterized in that: The base paper has a basis weight of 20-500 g / m 2 After the sizing slurry is sizing, the weight of the tensile wear-resistant washed kraft paper is 26~600g / m 2 .