Degradable pulp molded article and method for producing the same

Abstract

The application provides a degradable paper pulp molded product and a preparation method thereof, and comprises the following raw materials in mass fractions: waste paper pulp suspension 50-55 parts, cellulose 25-30 parts, liquor of enzyme hydrolysis of distiller's grains 10-15 parts, modified filler 6-10 parts, waterproof agent 5-7 parts, retention aid 0.03-0.07 parts, and bleaching agent 1-2 parts. The specific waste paper pulp suspension, cellulose, liquor of enzyme hydrolysis of distiller's grains and modified filler are used as raw materials, and the raw materials interact with each other and synergistically, so that the comprehensive performance of the degradable paper pulp molded product is improved.

Description

Technical Field

[0001] This invention belongs to the technical field of pulp molding products, specifically relating to a biodegradable pulp molding product and its preparation method. Background Technology

[0002] Pulp molding packaging material is an environmentally friendly packaging material. It is made primarily from natural fibers such as sugarcane pulp, bamboo pulp, paper scraps, and waste paper (such as newspapers and cardboard boxes) through a series of processes. The production process includes hydraulic pulping, vacuum adsorption molding on a metal mold, and direct curing. Due to its unique production process and material properties, pulp molding packaging material possesses the following characteristics: Environmental friendliness: Because the main raw material is renewable plant fiber, and recycled paper can be used in the production process, pulp molding packaging material is recyclable and biodegradable, with minimal environmental impact. Cushioning performance: Pulp molding packaging has excellent cushioning and shock absorption capabilities, determined by the elasticity and toughness of the fiber material itself. It can replace traditional foamed plastic packaging, performing excellently in protecting products from impact and vibration. Multifunctionality: Pulp molding packaging can be customized according to the shape and size of different products, suitable for packaging various types of items, such as electronic products, food, and cosmetics. Cost-effectiveness: Although initial investment may be higher, in the long run, pulp molded packaging reduces waste and lowers overall costs due to its recyclability. Printability: The surface of pulp molded packaging can be printed, including hot stamping, screen printing, and UV printing, allowing it to carry brand logos and marketing messages, enhancing product appeal. Antistatic properties: Compared to some traditional packaging materials, pulp molded packaging performs better in terms of antistatic properties, which is especially important for electronic product packaging. Stackability: Pulp molded packaging is typically designed for easy stacking, saving storage and transportation space. Applications of pulp molded packaging are wide-ranging, from industrial cushioning packaging to consumer product packaging, and even in the food service industry (such as tableware and lunch boxes). With the growing global demand for environmentally friendly packaging, pulp molded packaging is gradually becoming a popular green packaging solution. However, the overall performance of existing pulp molded packaging materials is not ideal. Summary of the Invention

[0003] The purpose of this invention is to provide a biodegradable pulp molded product and its preparation method.

[0004] To achieve the above objectives, the present invention provides the following technical solution:

[0005] A biodegradable pulp molded product comprises the following raw materials in parts by weight: 50-55 parts waste pulp suspension, 25-30 parts cellulose, 10-15 parts enzymatic hydrolysate of liquor lees, 6-10 parts modified filler, 5-7 parts waterproofing agent, 0.03-0.07 parts retention aid, and 1-2 parts bleaching agent.

[0006] Furthermore, the cellulose is selected from one or more of carboxymethyl cellulose, hydroxypropyl methyl cellulose, and cellulose ethers.

[0007] Furthermore, the cellulose is a mixture of carboxymethyl cellulose, hydroxypropyl methyl cellulose and cellulose ether in a mass ratio of 1:0.3-0.7:1.4-1.8.

[0008] Further, the preparation method of the enzymatic hydrolysate of baijiu lees is as follows: by mass, 1 part of baijiu lees is added to 8-10 parts of deionized water, followed by 0.2-0.4 parts of sodium hydroxide, and stirred at 55-60℃ for 4-5 hours; after the reaction is completed, dilute hydrochloric acid is added to adjust the pH to neutral, then 0.02 parts of neutral protease are added, and enzymatic hydrolysis is carried out at 27-30℃ for 1.5-2 hours. After the enzymatic hydrolysis is completed, sterilization is performed to obtain the enzymatic hydrolysate of baijiu lees.

[0009] Furthermore, the method for preparing the modified filler is as follows:

[0010] (1) Alumina, zinc oxide and carbon nanotubes are mixed to obtain a filler;

[0011] (2) Mix the filler with a mass ratio of 1:6-8:0.02-0.03, 60-65wt% ethanol aqueous solution, and silane coupling agent KH550, stir and react at 60-65℃ for 2-4h, filter to obtain solid, wash and dry to obtain modified filler.

[0012] Furthermore, the filler is a composite of alumina, zinc oxide and carbon nanotubes in a mass ratio of 1:1.3-1.5:0.4-0.8.

[0013] Furthermore, the alumina has a particle size of 1-10 μm and a specific surface area of ​​3-6 m². 2 / g.

[0014] Furthermore, the zinc oxide has a particle size of 30-50 nm and a specific surface area of ​​15-30 m². 2 / g.

[0015] Furthermore, the carbon nanotubes have a diameter of 2-4 nm, a length of 40-60 μm, and a specific surface area of ​​400-600 m². 2 / g.

[0016] This invention provides a method for preparing biodegradable pulp molded articles, comprising the following steps:

[0017] S1. The waste coated paper is crushed, soaked, pulped, filtered to obtain filter residue, and then washed to make a waste paper pulp suspension.

[0018] S2. After bleaching the waste paper pulp suspension, send it to the pulp conditioning tank, add cellulose and enzymatic hydrolysate of liquor lees, add retention aid, stir evenly, and then add modified filler. After stirring, the primary pulp is obtained.

[0019] S3. The primary pulp is used to uniformly adsorb fibers onto the lower mold of the molding die through negative pressure, and then immersed in a waterproofing agent solution for 22-25 minutes. After that, it is closed with the upper mold of the molding die, and the pulp molding wet blank is obtained after the mold is opened.

[0020] S4. Dry the wet pulp molding blank to a moisture content of 3-5%, place it in a mold and press it into shape to obtain biodegradable pulp molding products.

[0021] Compared with the prior art, the advantages and beneficial effects of the present invention are as follows: The present invention selects specific waste pulp suspension, cellulose, enzymatic hydrolysate of liquor lees and modified fillers as raw materials, which interact with each other and synergistically enhance the overall performance of biodegradable pulp molded products. Detailed Implementation

[0022] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] Example 1

[0024] This embodiment provides a biodegradable pulp molded product comprising the following raw materials in parts by weight: 52 parts waste paper pulp suspension, 27 parts cellulose, 13 parts enzymatic hydrolysate of liquor lees, 8 parts modified filler, 6 parts waterproofing agent, 0.04 parts retention aid, and 1.5 parts bleaching agent.

[0025] The cellulose is a mixture of carboxymethyl cellulose, hydroxypropyl methyl cellulose and cellulose ether in a mass ratio of 1:0.5:1.6.

[0026] The preparation method of the enzymatic hydrolysate of baijiu lees is as follows: by mass, 1 part of baijiu lees is added to 9 parts of deionized water, followed by 0.3 parts of sodium hydroxide, and the mixture is stirred at 57°C for 4-5 hours. After the reaction is completed, dilute hydrochloric acid is added to adjust the pH to neutral, and then 0.02 parts of neutral protease are added. The mixture is enzymatically hydrolyzed at 28°C for 1.7 hours. After the enzymatic hydrolysis is completed, the mixture is sterilized to obtain the enzymatic hydrolysate of baijiu lees.

[0027] The modified filler is prepared by:

[0028] (1) Alumina, zinc oxide and carbon nanotubes are mixed to obtain a filler;

[0029] (2) The filler with a mass ratio of 1:7:0.02, 63wt% ethanol aqueous solution and silane coupling agent KH550 were mixed and stirred at 62℃ for 3h. The solid was filtered, washed and dried to obtain the modified filler.

[0030] The filler is a composite of alumina, zinc oxide and carbon nanotubes in a mass ratio of 1:1.4:0.6.

[0031] The alumina particles have a particle size of 1-10 μm and a specific surface area of ​​3-6 m². 2 / g.

[0032] Zinc oxide has a particle size of 30-50 nm and a specific surface area of ​​15-30 m². 2 / g.

[0033] Carbon nanotubes have a diameter of 2-4 nm, a length of 40-60 μm, and a specific surface area of ​​400-600 m². 2 / g.

[0034] The method for preparing the biodegradable pulp molded article includes the following steps:

[0035] S1. The waste coated paper is crushed, soaked, pulped, filtered to obtain filter residue, and then washed to make a waste paper pulp suspension.

[0036] S2. After bleaching the waste paper pulp suspension, send it to the pulp conditioning tank, add cellulose and enzymatic hydrolysate of liquor lees, add retention aid, stir evenly, and then add modified filler. After stirring, the primary pulp is obtained.

[0037] S3. The primary pulp is used to uniformly adsorb fibers onto the lower mold of the molding die through negative pressure, and then immersed in a waterproofing agent solution for 23 minutes. After that, it is closed with the upper mold of the molding die, and the pulp molding wet blank is obtained after the mold is opened.

[0038] S4. Dry the wet pulp molded blank to a moisture content of 4%, place it in a mold and press it into shape to obtain a biodegradable pulp molded product.

[0039] Example 2

[0040] This embodiment provides a biodegradable pulp molded product comprising the following raw materials in parts by weight: 50 parts waste paper pulp suspension, 25 parts cellulose, 10 parts enzymatic hydrolysate of liquor lees, 6 parts modified filler, 5 parts waterproofing agent, 0.03 parts retention aid, and 1 part bleaching agent.

[0041] The cellulose is a mixture of carboxymethyl cellulose, hydroxypropyl methyl cellulose and cellulose ether in a mass ratio of 1:0.3:1.4.

[0042] The preparation method of the enzymatic hydrolysate of baijiu lees is as follows: by mass, 1 part of baijiu lees is added to 8 parts of deionized water, followed by 0.2 parts of sodium hydroxide, and the mixture is stirred at 55°C for 4 hours. After the reaction is completed, dilute hydrochloric acid is added to adjust the pH to neutral, and then 0.02 parts of neutral protease are added. The mixture is enzymatically hydrolyzed at 27°C for 1.5 hours. After the enzymatic hydrolysis is completed, the mixture is sterilized to obtain the enzymatic hydrolysate of baijiu lees.

[0043] The modified filler is prepared by:

[0044] (1) Alumina, zinc oxide and carbon nanotubes are mixed to obtain a filler;

[0045] (2) The filler with a mass ratio of 1:6:0.02, 60wt% ethanol aqueous solution and silane coupling agent KH550 are mixed and stirred at 60℃ for 2h. The solid is filtered, washed and dried to obtain the modified filler.

[0046] The filler is a composite of alumina, zinc oxide and carbon nanotubes in a mass ratio of 1:1.3:0.4.

[0047] The alumina particles have a particle size of 1-10 μm and a specific surface area of ​​3-6 m². 2 / g.

[0048] Zinc oxide has a particle size of 30-50 nm and a specific surface area of ​​15-30 m². 2 / g.

[0049] Carbon nanotubes have a diameter of 2-4 nm, a length of 40-60 μm, and a specific surface area of ​​400-600 m². 2 / g.

[0050] The method for preparing the biodegradable pulp molded article includes the following steps:

[0051] S1. The waste coated paper is crushed, soaked, pulped, filtered to obtain filter residue, and then washed to make a waste paper pulp suspension.

[0052] S2. After bleaching the waste paper pulp suspension, send it to the pulp conditioning tank, add cellulose and enzymatic hydrolysate of liquor lees, add retention aid, stir evenly, and then add modified filler. After stirring, the primary pulp is obtained.

[0053] S3. The primary pulp is used to uniformly adsorb fibers onto the lower mold of the molding die through negative pressure, and then immersed in a waterproofing agent solution for 22 minutes. After that, it is closed with the upper mold of the molding die, and the pulp molding wet blank is obtained after the mold is opened.

[0054] S4. Dry the wet pulp molded blank to a moisture content of 3%, place it in a mold and press it into shape to obtain a biodegradable pulp molded product.

[0055] Example 3

[0056] This embodiment provides a biodegradable pulp molded product, comprising the following raw materials in parts by weight: 55 parts waste paper pulp suspension, 30 parts cellulose, 15 parts enzymatic hydrolysate of liquor lees, 10 parts modified filler, 7 parts waterproofing agent, 0.07 parts retention aid, and 2 parts bleaching agent.

[0057] The cellulose is a mixture of carboxymethyl cellulose, hydroxypropyl methyl cellulose and cellulose ether in a mass ratio of 1:0.7:1.8.

[0058] The preparation method of the enzymatic hydrolysate of baijiu lees is as follows: by mass, 1 part of baijiu lees is added to 10 parts of deionized water, followed by 0.4 parts of sodium hydroxide, and the mixture is stirred at 60°C for 5 hours. After the reaction is completed, dilute hydrochloric acid is added to adjust the pH to neutral, and then 0.02 parts of neutral protease are added. The mixture is enzymatically hydrolyzed at 30°C for 2 hours. After the enzymatic hydrolysis is completed, the mixture is sterilized to obtain the enzymatic hydrolysate of baijiu lees.

[0059] The modified filler is prepared by:

[0060] (1) Alumina, zinc oxide and carbon nanotubes are mixed to obtain a filler;

[0061] (2) Mix the filler with a mass ratio of 1:8:0.03, 60-65wt% ethanol aqueous solution, and silane coupling agent KH550, stir and react at 65℃ for 4h, filter to obtain solid, wash and dry to obtain modified filler.

[0062] The filler is a composite of alumina, zinc oxide and carbon nanotubes in a mass ratio of 1:1.5:0.8.

[0063] The alumina particles have a particle size of 1-10 μm and a specific surface area of ​​3-6 m². 2 / g.

[0064] Zinc oxide has a particle size of 30-50 nm and a specific surface area of ​​15-30 m². 2 / g.

[0065] Carbon nanotubes have a diameter of 2-4 nm, a length of 40-60 μm, and a specific surface area of ​​400-600 m². 2 / g.

[0066] The method for preparing the biodegradable pulp molded article includes the following steps:

[0067] S1. The waste coated paper is crushed, soaked, pulped, filtered to obtain filter residue, and then washed to make a waste paper pulp suspension.

[0068] S2. After bleaching the waste paper pulp suspension, send it to the pulp conditioning tank, add cellulose and enzymatic hydrolysate of liquor lees, add retention aid, stir evenly, and then add modified filler. After stirring, the primary pulp is obtained.

[0069] S3. The primary pulp is used to uniformly adsorb fibers onto the lower mold of the molding die through negative pressure, and then immersed in a waterproofing agent solution for 25 minutes. After that, it is closed with the upper mold of the molding die, and the pulp molding wet blank is obtained after the mold is opened.

[0070] S4. Dry the wet pulp molded blank to a moisture content of 5%, place it in a mold and press it into shape to obtain a biodegradable pulp molded product.

[0071] Comparative Example 1

[0072] The difference between this comparative example and Example 1 is that the proportions of waste paper pulp suspension and cellulose are different.

[0073] A biodegradable pulp molded product comprises the following raw materials in parts by weight: 45 parts waste paper pulp suspension, 34 parts cellulose, 13 parts enzymatic hydrolysate of liquor lees, 8 parts modified filler, 6 parts waterproofing agent, 0.04 parts retention aid, and 1.5 parts bleaching agent.

[0074] The cellulose is a mixture of carboxymethyl cellulose, hydroxypropyl methyl cellulose and cellulose ether in a mass ratio of 1:0.5:1.6.

[0075] The preparation method of the enzymatic hydrolysate of baijiu lees is as follows: by mass, 1 part of baijiu lees is added to 9 parts of deionized water, followed by 0.3 parts of sodium hydroxide, and the mixture is stirred at 57°C for 4-5 hours. After the reaction is completed, dilute hydrochloric acid is added to adjust the pH to neutral, and then 0.02 parts of neutral protease are added. The mixture is enzymatically hydrolyzed at 28°C for 1.7 hours. After the enzymatic hydrolysis is completed, the mixture is sterilized to obtain the enzymatic hydrolysate of baijiu lees.

[0076] The modified filler is prepared by:

[0077] (1) Alumina, zinc oxide and carbon nanotubes are mixed to obtain a filler;

[0078] (2) The filler with a mass ratio of 1:7:0.02, 63wt% ethanol aqueous solution and silane coupling agent KH550 were mixed and stirred at 62℃ for 3h. The solid was filtered, washed and dried to obtain the modified filler.

[0079] The filler is a composite of alumina, zinc oxide and carbon nanotubes in a mass ratio of 1:1.4:0.6.

[0080] The alumina particles have a particle size of 1-10 μm and a specific surface area of ​​3-6 m². 2 / g.

[0081] Zinc oxide has a particle size of 30-50 nm and a specific surface area of ​​15-30 m². 2 / g.

[0082] Carbon nanotubes have a diameter of 2-4 nm, a length of 40-60 μm, and a specific surface area of ​​400-600 m².2 / g.

[0083] The method for preparing the biodegradable pulp molded article includes the following steps:

[0084] S1. The waste coated paper is crushed, soaked, pulped, filtered to obtain filter residue, and then washed to make a waste paper pulp suspension.

[0085] S2. After bleaching the waste paper pulp suspension, send it to the pulp conditioning tank, add cellulose and enzymatic hydrolysate of liquor lees, add retention aid, stir evenly, and then add modified filler. After stirring, the primary pulp is obtained.

[0086] S3. The primary pulp is used to uniformly adsorb fibers onto the lower mold of the molding die through negative pressure, and then immersed in a waterproofing agent solution for 23 minutes. After that, it is closed with the upper mold of the molding die, and the pulp molding wet blank is obtained after the mold is opened.

[0087] S4. Dry the wet pulp molded blank to a moisture content of 4%, place it in a mold and press it into shape to obtain a biodegradable pulp molded product.

[0088] Comparative Example 2

[0089] The difference between this comparative example and Example 1 is that the proportions of waste paper pulp suspension and enzymatic hydrolysate of liquor lees are different.

[0090] A biodegradable pulp molded product comprises the following raw materials in parts by weight: 45 parts waste paper pulp suspension, 27 parts cellulose, 20 parts enzymatic hydrolysate of liquor lees, 8 parts modified filler, 6 parts waterproofing agent, 0.04 parts retention aid, and 1.5 parts bleaching agent.

[0091] The cellulose is a mixture of carboxymethyl cellulose, hydroxypropyl methyl cellulose and cellulose ether in a mass ratio of 1:0.5:1.6.

[0092] The preparation method of the enzymatic hydrolysate of baijiu lees is as follows: by mass, 1 part of baijiu lees is added to 9 parts of deionized water, followed by 0.3 parts of sodium hydroxide, and the mixture is stirred at 57°C for 4-5 hours. After the reaction is completed, dilute hydrochloric acid is added to adjust the pH to neutral, and then 0.02 parts of neutral protease are added. The mixture is enzymatically hydrolyzed at 28°C for 1.7 hours. After the enzymatic hydrolysis is completed, the mixture is sterilized to obtain the enzymatic hydrolysate of baijiu lees.

[0093] The modified filler is prepared by:

[0094] (1) Alumina, zinc oxide and carbon nanotubes are mixed to obtain a filler;

[0095] (2) The filler with a mass ratio of 1:7:0.02, 63wt% ethanol aqueous solution and silane coupling agent KH550 were mixed and stirred at 62℃ for 3h. The solid was filtered, washed and dried to obtain the modified filler.

[0096] The filler is a composite of alumina, zinc oxide and carbon nanotubes in a mass ratio of 1:1.4:0.6.

[0097] The alumina particles have a particle size of 1-10 μm and a specific surface area of ​​3-6 m². 2 / g.

[0098] Zinc oxide has a particle size of 30-50 nm and a specific surface area of ​​15-30 m². 2 / g.

[0099] Carbon nanotubes have a diameter of 2-4 nm, a length of 40-60 μm, and a specific surface area of ​​400-600 m². 2 / g.

[0100] The method for preparing the biodegradable pulp molded article includes the following steps:

[0101] S1. The waste coated paper is crushed, soaked, pulped, filtered to obtain filter residue, and then washed to make a waste paper pulp suspension.

[0102] S2. After bleaching the waste paper pulp suspension, send it to the pulp conditioning tank, add cellulose and enzymatic hydrolysate of liquor lees, add retention aid, stir evenly, and then add modified filler. After stirring, the primary pulp is obtained.

[0103] S3. The primary pulp is used to uniformly adsorb fibers onto the lower mold of the molding die through negative pressure, and then immersed in a waterproofing agent solution for 23 minutes. After that, it is closed with the upper mold of the molding die, and the pulp molding wet blank is obtained after the mold is opened.

[0104] S4. Dry the wet pulp molded blank to a moisture content of 4%, place it in a mold and press it into shape to obtain a biodegradable pulp molded product.

[0105] Comparative Example 3

[0106] The difference between this comparative example and Example 1 is that the proportions of cellulose and the enzymatic hydrolysate of baijiu lees are different.

[0107] A biodegradable pulp molded product comprises the following raw materials in parts by weight: 52 parts waste paper pulp suspension, 20 parts cellulose, 20 parts enzymatic hydrolysate of liquor lees, 8 parts modified filler, 6 parts waterproofing agent, 0.04 parts retention aid, and 1.5 parts bleaching agent.

[0108] The cellulose is a mixture of carboxymethyl cellulose, hydroxypropyl methyl cellulose and cellulose ether in a mass ratio of 1:0.5:1.6.

[0109] The preparation method of the enzymatic hydrolysate of baijiu lees is as follows: by mass, 1 part of baijiu lees is added to 9 parts of deionized water, followed by 0.3 parts of sodium hydroxide, and the mixture is stirred at 57°C for 4-5 hours. After the reaction is completed, dilute hydrochloric acid is added to adjust the pH to neutral, and then 0.02 parts of neutral protease are added. The mixture is enzymatically hydrolyzed at 28°C for 1.7 hours. After the enzymatic hydrolysis is completed, the mixture is sterilized to obtain the enzymatic hydrolysate of baijiu lees.

[0110] The modified filler is prepared by:

[0111] (1) Alumina, zinc oxide and carbon nanotubes are mixed to obtain a filler;

[0112] (2) The filler with a mass ratio of 1:7:0.02, 63wt% ethanol aqueous solution and silane coupling agent KH550 were mixed and stirred at 62℃ for 3h. The solid was filtered, washed and dried to obtain the modified filler.

[0113] The filler is a composite of alumina, zinc oxide and carbon nanotubes in a mass ratio of 1:1.4:0.6.

[0114] The alumina particles have a particle size of 1-10 μm and a specific surface area of ​​3-6 m². 2 / g.

[0115] Zinc oxide has a particle size of 30-50 nm and a specific surface area of ​​15-30 m². 2 / g.

[0116] Carbon nanotubes have a diameter of 2-4 nm, a length of 40-60 μm, and a specific surface area of ​​400-600 m². 2 / g.

[0117] The method for preparing the biodegradable pulp molded article includes the following steps:

[0118] S1. The waste coated paper is crushed, soaked, pulped, filtered to obtain filter residue, and then washed to make a waste paper pulp suspension.

[0119] S2. After bleaching the waste paper pulp suspension, send it to the pulp conditioning tank, add cellulose and enzymatic hydrolysate of liquor lees, add retention aid, stir evenly, and then add modified filler. After stirring, the primary pulp is obtained.

[0120] S3. The primary pulp is used to uniformly adsorb fibers onto the lower mold of the molding die through negative pressure, and then immersed in a waterproofing agent solution for 23 minutes. After that, it is closed with the upper mold of the molding die, and the pulp molding wet blank is obtained after the mold is opened.

[0121] S4. Dry the wet pulp molded blank to a moisture content of 4%, place it in a mold and press it into shape to obtain a biodegradable pulp molded product.

[0122] Comparative Example 4

[0123] The difference between this comparative example and Example 1 is that the filler is a composite of alumina, zinc oxide, and carbon nanotubes in a mass ratio of 1:1:1.

[0124] A biodegradable pulp molded product comprises the following raw materials in parts by weight: 52 parts waste paper pulp suspension, 27 parts cellulose, 13 parts enzymatic hydrolysate of liquor lees, 8 parts modified filler, 6 parts waterproofing agent, 0.04 parts retention aid, and 1.5 parts bleaching agent.

[0125] The cellulose is a mixture of carboxymethyl cellulose, hydroxypropyl methyl cellulose and cellulose ether in a mass ratio of 1:0.5:1.6.

[0126] The preparation method of the enzymatic hydrolysate of baijiu lees is as follows: by mass, 1 part of baijiu lees is added to 9 parts of deionized water, followed by 0.3 parts of sodium hydroxide, and the mixture is stirred at 57°C for 4-5 hours. After the reaction is completed, dilute hydrochloric acid is added to adjust the pH to neutral, and then 0.02 parts of neutral protease are added. The mixture is enzymatically hydrolyzed at 28°C for 1.7 hours. After the enzymatic hydrolysis is completed, the mixture is sterilized to obtain the enzymatic hydrolysate of baijiu lees.

[0127] The modified filler is prepared by:

[0128] (1) Alumina, zinc oxide and carbon nanotubes are mixed to obtain a filler;

[0129] (2) The filler with a mass ratio of 1:7:0.02, 63wt% ethanol aqueous solution and silane coupling agent KH550 were mixed and stirred at 62℃ for 3h. The solid was filtered, washed and dried to obtain the modified filler.

[0130] The filler is a composite of alumina, zinc oxide and carbon nanotubes in a mass ratio of 1:1:1.

[0131] The alumina particles have a particle size of 1-10 μm and a specific surface area of ​​3-6 m². 2 / g.

[0132] Zinc oxide has a particle size of 30-50 nm and a specific surface area of ​​15-30 m². 2 / g.

[0133] Carbon nanotubes have a diameter of 2-4 nm, a length of 40-60 μm, and a specific surface area of ​​400-600 m². 2 / g.

[0134] The method for preparing the biodegradable pulp molded article includes the following steps:

[0135] S1. The waste coated paper is crushed, soaked, pulped, filtered to obtain filter residue, and then washed to make a waste paper pulp suspension.

[0136] S2. After bleaching the waste paper pulp suspension, send it to the pulp conditioning tank, add cellulose and enzymatic hydrolysate of liquor lees, add retention aid, stir evenly, and then add modified filler. After stirring, the primary pulp is obtained.

[0137] S3. The primary pulp is used to uniformly adsorb fibers onto the lower mold of the molding die through negative pressure, and then immersed in a waterproofing agent solution for 23 minutes. After that, it is closed with the upper mold of the molding die, and the pulp molding wet blank is obtained after the mold is opened.

[0138] S4. Dry the wet pulp molded blank to a moisture content of 4%, place it in a mold and press it into shape to obtain a biodegradable pulp molded product.

[0139] Comparative Example 5

[0140] The difference between this comparative example and Example 1 is that the cellulose is a mixture of carboxymethyl cellulose, hydroxypropyl methyl cellulose and cellulose ether in a mass ratio of 1:1:1.

[0141] A biodegradable pulp molded product comprises the following raw materials in parts by weight: 52 parts waste paper pulp suspension, 27 parts cellulose, 13 parts enzymatic hydrolysate of liquor lees, 8 parts modified filler, 6 parts waterproofing agent, 0.04 parts retention aid, and 1.5 parts bleaching agent.

[0142] The cellulose is a mixture of carboxymethyl cellulose, hydroxypropyl methyl cellulose and cellulose ether in a mass ratio of 1:1:1.

[0143] The preparation method of the enzymatic hydrolysate of baijiu lees is as follows: by mass, 1 part of baijiu lees is added to 9 parts of deionized water, followed by 0.3 parts of sodium hydroxide, and the mixture is stirred at 57°C for 4-5 hours. After the reaction is completed, dilute hydrochloric acid is added to adjust the pH to neutral, and then 0.02 parts of neutral protease are added. The mixture is enzymatically hydrolyzed at 28°C for 1.7 hours. After the enzymatic hydrolysis is completed, the mixture is sterilized to obtain the enzymatic hydrolysate of baijiu lees.

[0144] The modified filler is prepared by:

[0145] (1) Alumina, zinc oxide and carbon nanotubes are mixed to obtain a filler;

[0146] (2) The filler with a mass ratio of 1:7:0.02, 63wt% ethanol aqueous solution and silane coupling agent KH550 were mixed and stirred at 62℃ for 3h. The solid was filtered, washed and dried to obtain the modified filler.

[0147] The filler is a composite of alumina, zinc oxide and carbon nanotubes in a mass ratio of 1:1.4:0.6.

[0148] The alumina particles have a particle size of 1-10 μm and a specific surface area of ​​3-6 m². 2 / g.

[0149] Zinc oxide has a particle size of 30-50 nm and a specific surface area of ​​15-30 m². 2 / g.

[0150] Carbon nanotubes have a diameter of 2-4 nm, a length of 40-60 μm, and a specific surface area of ​​400-600 m². 2 / g.

[0151] The method for preparing the biodegradable pulp molded article includes the following steps:

[0152] S1. The waste coated paper is crushed, soaked, pulped, filtered to obtain filter residue, and then washed to make a waste paper pulp suspension.

[0153] S2. After bleaching the waste paper pulp suspension, send it to the pulp conditioning tank, add cellulose and enzymatic hydrolysate of liquor lees, add retention aid, stir evenly, and then add modified filler. After stirring, the primary pulp is obtained.

[0154] S3. The primary pulp is used to uniformly adsorb fibers onto the lower mold of the molding die through negative pressure, and then immersed in a waterproofing agent solution for 23 minutes. After that, it is closed with the upper mold of the molding die, and the pulp molding wet blank is obtained after the mold is opened.

[0155] S4. Dry the wet pulp molded blank to a moisture content of 4%, place it in a mold and press it into shape to obtain a biodegradable pulp molded product.

[0156] Performance testing

[0157] The pulp molded products obtained in Examples 1-3 and Comparative Examples 1-5 were subjected to performance tests. Dry tensile strength was tested according to GB / T12914-2018 "Determination of Tensile Strength of Paper and Paperboard - Constant Rate Tensile Test". The sampling direction was longitudinal, the sample size was 250mm × 15mm, and the tensile speed was 20mm / min. Before testing, the samples were placed in an environment with a temperature of 23℃ and a relative humidity of 50% for 24 hours. Tear resistance was tested according to national standard GB / T455-2002 "Determination of Tensile Strength of Paper and Paperboard - Constant Rate Tensile Test". The tear strength of paper and paperboard was determined using a paper tear tester. Water absorption was determined by placing a 50mm × 50mm sample in a 50℃ oven for 24 hours, weighing it (m1), and then immersing it in pre-prepared 30℃ tap water for 24 hours. After air drying, the sample was gently wiped dry with filter paper, weighed (m2), and the water absorption rate was calculated as (m2 - m1) / m1 × 100%. The test results are shown in Table 1 below.

[0158] Table 1 Performance Test Results

[0159]

[0160] The results show that the products of Examples 1-3 have excellent overall performance, especially the overall performance of Example 1, which is mainly due to the good synergistic effect between the components.

[0161] The comparative example, however, did not employ the necessary technical solutions, resulting in significantly inferior performance compared to the embodiment in the corresponding tests. The above experimental results further demonstrate the importance of the technical solutions defined in this invention for its technical effects.

[0162] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A biodegradable pulp molded product, characterized in that, The raw materials include the following parts by weight: 50-55 parts waste paper pulp suspension, 25-30 parts cellulose, 10-15 parts enzymatic hydrolysate of liquor lees, 6-10 parts modified filler, 5-7 parts waterproofing agent, 0.03-0.07 parts retention aid, and 1-2 parts bleaching agent. The cellulose is a mixture of carboxymethyl cellulose, hydroxypropyl methyl cellulose and cellulose ether in a mass ratio of 1:0.3-0.7:1.4-1.8; The preparation method of Baijiu lees enzymatic hydrolysate is as follows: by mass, add 1 part of Baijiu lees to 8-10 parts of deionized water, then add 0.2-0.4 parts of sodium hydroxide, stir and react at 55-60℃ for 4-5 hours; after the reaction is completed, add dilute hydrochloric acid to adjust the pH to neutral, then add 0.02 parts of neutral protease, and carry out enzymatic hydrolysis at 27-30℃ for 1.5-2 hours. After the enzymatic hydrolysis is completed, sterilize to obtain Baijiu lees enzymatic hydrolysate; The preparation method of the modified filler is as follows: (1) Alumina, zinc oxide and carbon nanotubes are mixed to obtain a filler; (2) Mix the filler with a mass ratio of 1:6-8:0.02-0.03, 60-65wt% ethanol aqueous solution, and silane coupling agent KH550, stir and react at 60-65℃ for 2-4h, filter to obtain solid, wash and dry to obtain modified filler; The filler is a composite of alumina, zinc oxide and carbon nanotubes in a mass ratio of 1:1.3-1.5:0.4-0.8; alumina particle size 1-10 μm, specific surface area 3-6 m 2 / g; Zinc oxide has a particle size of 30-50 nm and a specific surface area of ​​15-30 m². 2 / g; Carbon nanotubes have a diameter of 2-4 nm, a length of 40-60 μm, and a specific surface area of ​​400-600 m². 2 / g.

2. A method for preparing a biodegradable pulp molded article as described in claim 1, characterized in that, Includes the following steps: S1. The waste coated paper is crushed, soaked, pulped, filtered to obtain filter residue, and then washed to make a waste paper pulp suspension. S2. After bleaching the waste paper pulp suspension, send it to the pulp conditioning tank, add cellulose and enzymatic hydrolysate of liquor lees, add retention aid, stir evenly, and then add modified filler. After stirring, the primary pulp is obtained. S3. The primary pulp is used to uniformly adsorb fibers onto the lower mold of the molding die through negative pressure, and then immersed in a waterproofing agent solution for 22-25 minutes. After that, it is closed with the upper mold of the molding die, and the pulp molding wet blank is obtained after the mold is opened. S4. Dry the wet pulp molding blank to a moisture content of 3-5%, place it in a mold and press it into shape to obtain biodegradable pulp molding products.

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