Raw material composition of enhanced surface sizing agent for corrugated paper and preparation method of raw material composition

Abstract

The invention provides a raw material composition of an enhanced surface sizing agent for corrugated paper. The raw material composition comprises the following components in parts by weight: 2-10 parts of starch, 0.01-4 parts of amylase, 0.01-3 parts of carboxymethylcellulose and 5-30 parts of sodium sulfate. The invention also provides a preparation method of the enhanced surface sizing agent for corrugated paper, which adopts the raw material composition and specifically comprises the following steps: adding starch into a reactor, heating to a reaction temperature, and adding amylase for gelatinization reaction; after gelatinization is finished, reducing the temperature to room temperature, adding carboxymethyl cellulose, and stirring to fully mix the carboxymethyl cellulose and the carboxymethyl cellulose; adding sodium sulfate into the reactor, and fully stirring and reacting to obtain the enhanced surface sizing agent for the corrugated paper. The surface sizing agent is prepared by gelatinizing and modifying starch and adding carboxymethyl cellulose and sodium sulfate, and the surface strength of paper can be remarkably improved when the product is applied to corrugated paper. The preparation method is simple and obvious in effect.

Description

Technical Field

[0001] The invention relates to the technical field of papermaking sizing agent preparation, in particular to a reinforced surface sizing agent raw material composition for corrugated paper and a preparation method thereof. Background Art

[0002] Corrugated paper is a multi-layer adhesive body. During long-term use, it is prone to fiber aging and keratinization problems, which reduces the elasticity and softness of the recycled fibers, making it difficult to cross-link the fibers and reducing the bonding strength, resulting in low strength of corrugated paperboard made from recycled cardboard.

[0003] CN109577084A discloses a surface sizing agent for corrugated paper, comprising a first component and a second component, wherein the first component comprises surface sizing starch, aluminum silicate fiber and wollastonite, and the second component is selected from polyvinyl alcohol, AKD or styrene acrylic emulsion. The corrugated paper prepared by the surface sizing agent has strong transverse ring crush strength and longitudinal ring crush strength, and has good waterproof and moisture-proof properties.

[0004] CN106968130A discloses a method for preparing a corrugated paper surface sizing agent, wherein tetrabutyl titanate, an emulsifier, molten paraffin and rosin are uniformly mixed, and then emulsified, and the obtained inorganic-organic hybrid emulsion is mixed with a stearic acid hydrophobically modified oxidized starch suspension to obtain a corrugated paper surface sizing agent. The corrugated paper surface sizing agent prepared by the invention has not only high strength, but also high wear resistance and excellent water resistance, high bonding strength, good use performance, and is suitable for surface sizing of corrugated paper.

[0005] Developing new water-resistant surface sizing agents for corrugated paper and improving the surface strength of corrugated paper has important research and practical value. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a raw material composition of an enhanced surface sizing agent for corrugated paper and a preparation method thereof, so as to improve the surface strength of the corrugated paper, thereby solving the above technical problems existing in the prior art.

[0007] The present invention is achieved by adopting the following technical solutions:

[0008] The first aspect of the present invention is to provide a raw material composition of an enhanced surface sizing agent for corrugated paper, comprising the following components in parts by weight: 2 to 10 parts of starch, 0.01 to 4 parts of amylase, 0.01 to 3 parts of carboxymethyl cellulose, and 5 to 30 parts of sodium sulfate.

[0009] The amylase may be selected from the commonly used types in the art, such as α-amylase, β-amylase, isoamylase, etc. The role of adding amylase in the present invention is to denature the starch and reduce the viscosity of the starch after gelatinization.

[0010] Preferably, the starch is selected from at least one of potato starch, corn starch and tapioca starch.

[0011] The second aspect of the present invention is to provide a method for preparing an enhanced surface sizing agent for corrugated paper, using the above raw material composition, and specifically comprising the following steps:

[0012] S1, adding starch into a reactor, heating to the reaction temperature, and adding amylase to perform gelatinization reaction;

[0013] S2. After gelatinization is completed, cool to room temperature, add carboxymethyl cellulose, and stir to mix thoroughly;

[0014] S3, adding sodium sulfate into the reactor, stirring the reaction sufficiently to obtain the enhanced surface sizing agent for corrugated paper.

[0015] When preparing a starch-based sizing agent, the inventor accidentally added sodium sulfate while adding carboxymethyl cellulose after gelatinization and denaturation of starch. The resulting surface sizing agent unexpectedly significantly improved the surface strength of corrugated paper. Such inorganic salts usually contribute little to the surface strength of paper, and the specific mechanism is unclear. It is preliminarily speculated that the addition of sodium sulfate may synergistically enhance the hydrogen bonding force between carboxymethyl cellulose and starch, thereby enhancing its bonding strength with paper, thereby improving the surface strength of corrugated paper. Based on the above unexpected discovery, the inventor completed the present invention.

[0016] Preferably, in step S1, the gelatinization reaction temperature is 40-90° C., and the reaction time is 0.5-2 h.

[0017] Preferably, in step S2, the mixing time after adding carboxymethyl cellulose is 0.5 to 3 hours.

[0018] Preferably, in step S3, the reaction time is 0.5 to 3.5 h.

[0019] Preferably, after step S3, a filtering and impurity removal step is further included. More preferably, the filtering screen is a 325 mesh screen.

[0020] Compared with the prior art, the present invention has the following beneficial effects: the present invention prepares a surface sizing agent by gelatinizing and modifying starch, adding carboxymethyl cellulose and sodium sulfate, and the product can significantly improve the surface strength of corrugated paper when applied to the paper. The preparation method of the present invention is simple and has obvious effects. DETAILED DESCRIPTION

[0021] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only used as examples, but are not used to limit the scope of the present invention. Those skilled in the art can think of other obvious variations. The basic principles of the present invention defined in the following description can be applied to other embodiments, variations, improvements, equivalent solutions, and other technical solutions that do not deviate from the spirit and scope of the present invention.

[0022] The instruments or raw materials in the present invention without indicating the manufacturer are all conventional commercial instruments or raw materials.

[0023] Unless otherwise mentioned, the detection indicators involved in the embodiments of the present invention are detected by conventional detection methods in the art.

[0024] Example 1

[0025] A reinforced surface sizing agent for corrugated paper, the preparation method of which comprises the following steps:

[0026] (1) Add 2 parts of corn starch into a reactor, raise the temperature to 50°C, and add 0.1 parts of amylase to gelatinize the starch for 0.5 h.

[0027] (2) Then the temperature was lowered to room temperature, and 0.01 parts of carboxymethyl cellulose was added and stirred for 1 hour to mix the mixture with the starch.

[0028] (3) Next, 5 parts of sodium sulfate were added, and the mixture was stirred to allow the components to be fully mixed and react for 1 hour. Finally, impurities were removed by filtering with a 325-mesh filter to obtain a reinforced surface sizing agent for corrugated paper.

[0029] Example 2

[0030] A reinforced surface sizing agent for corrugated paper, the preparation method of which comprises the following steps:

[0031] (1) 6 parts of potato starch were added into a reactor and the temperature was raised to 60°C. 1 part of amylase was added to gelatinize the starch for 2 hours.

[0032] (2) Then the temperature was lowered to room temperature, 0.5 parts of carboxymethyl cellulose was added, and the mixture was stirred for 1.5 hours to mix with the starch.

[0033] (3) Then, 15 parts of sodium sulfate were added, and the mixture was stirred to allow the components to be fully mixed and react for 2 hours. Finally, impurities were removed by filtering with a 325-mesh filter to obtain a reinforced surface sizing agent for corrugated paper.

[0034] Example 3

[0035] A reinforced surface sizing agent for corrugated paper, the preparation method of which comprises the following steps:

[0036] (1) 6 parts of cassava starch were added into a reactor and the temperature was raised to 75°C. 2 parts of amylase were added to gelatinize the starch for 0.5 h.

[0037] (2) The temperature was then lowered to room temperature, and 1.5 parts of carboxymethyl cellulose was added and stirred for 1.5 hours to mix the mixture with the starch.

[0038] (3) Next, 20 parts of sodium sulfate were added, and the mixture was stirred to allow the components to be fully mixed and react for 2 hours. Finally, impurities were removed by filtering with a 325-mesh filter to obtain a reinforced surface sizing agent for corrugated paper.

[0039] Example 4

[0040] A reinforced surface sizing agent for corrugated paper, the preparation method of which comprises the following steps:

[0041] (1) 10 parts of cassava starch were added into a reactor and the temperature was raised to 90°C. 4 parts of amylase were added to gelatinize the starch for 0.5 h.

[0042] (2) Then cool to room temperature, add 3 parts of carboxymethyl cellulose, and stir for 2 hours to mix it with the starch.

[0043] (3) Then, 30 parts of sodium sulfate were added, and the mixture was stirred to allow the components to be fully mixed and react for 3 hours. Finally, impurities were removed by filtering with a 325-mesh filter to obtain an enhanced surface sizing agent for corrugated paper.

[0044] Comparative Example 1

[0045] Compared with Example 1, no sodium sulfate was added. The specific process is as follows:

[0046] (1) Add 2 parts of corn starch into a reactor, raise the temperature to 50°C, and add 0.1 parts of amylase to gelatinize the starch for 0.5 h.

[0047] (2) Then cool to room temperature, add 0.01 parts of carboxymethyl cellulose, and stir for 1 hour to mix it with the starch.

[0048] (3) Filter with a 325-mesh filter to remove impurities and obtain a surface sizing agent for corrugated paper.

[0049] Application Examples

[0050] Preparation of sizing solution: dilute the sizing agent prepared in the examples and comparative examples with deionized water to 15wt%; prepare 500g of 10wt% oxidized starch aqueous solution, heat to 90°C, gelatinize for 20 minutes, cool to 40°C, add the diluted sizing agent (oxidized starch (dry): sizing agent (wet) = 50:2), and then dilute with water to 8wt% to prepare a sizing solution.

[0051] Surface sizing of corrugated paper: sizing solutions prepared in the embodiment and comparative example were respectively applied on 120g corrugated base paper using a 10# coating rod, with a coating amount of 2g / m 2 After coating, the paper samples were dried in an oven at 110°C for 120 seconds, taken out, cooled to room temperature, and the surface strength of each paper sample was measured using a J-IGT350 IGT printing adaptor. The test results are shown in Table 1.

[0052] Table 1 Paper sample test data

[0053] sample Surface strength (m / s) Example 1 1.56 Example 2 1.49 Example 3 1.58 Example 4 1.52 Comparative Example 1 1.17

[0054] It can be seen from the above application results that the sizing agent prepared by using Examples 1 to 4 of the present invention can significantly improve the surface strength of corrugated paper compared with the comparative example, indicating that there is a significant synergistic effect between sodium sulfate and other raw materials.

[0055] It should be understood by those skilled in the art that the above embodiments are only examples and do not limit the present invention. The purpose of the present invention has been fully and effectively achieved. The functional and structural principles of the present invention have been demonstrated and explained in the embodiments, and the embodiments of the present invention may be deformed or modified in any way without departing from the principles.

Claims

1. A raw material composition of an enhanced surface sizing agent for corrugated paper, characterized in that: The invention comprises the following components in parts by weight: 2 to 10 parts of starch, 0.01 to 4 parts of amylase, 0.01 to 3 parts of carboxymethyl cellulose and 5 to 30 parts of sodium sulfate.

2. The raw material composition according to claim 1, characterized in that: The amylase is selected from at least one of α-amylase, β-amylase and isoamylase.

3. The raw material composition according to claim 1, characterized in that: The dosage of the amylase is 0.1 to 4 parts.

4. The raw material composition according to claim 1, characterized in that The starch is selected from at least one of potato starch, corn starch and tapioca starch.

5. A method for preparing an enhanced surface sizing agent for corrugated paper, characterized in that: The raw material composition according to any one of claims 1 to 4 is used, and specifically comprises the following steps: S1, adding starch into a reactor, heating to the reaction temperature, and adding amylase to perform gelatinization reaction; S2. After gelatinization is completed, cool to room temperature, add carboxymethyl cellulose, and stir to mix thoroughly; S3, adding sodium sulfate into the reactor, stirring the reaction sufficiently to obtain the enhanced surface sizing agent for corrugated paper.

6. The method according to claim 5, characterized in that In step S1, the gelatinization reaction temperature is 40-90° C., and the reaction time is 0.5-2 h.

7. The method according to claim 5, characterized in that In step S2, the mixing time after adding carboxymethyl cellulose is 0.5 to 3 hours.

8. The method according to claim 5, characterized in that In step S3, the reaction time is 0.5 to 3.5 hours.

9. The method according to claim 5, characterized in that After step S3, a filtering and impurity removal step is further included.

10. The method according to claim 9, characterized in that The filter screen used for filtration is a 325 mesh filter screen.