CN101314930A - Special surface sizing agent for corrugated paper and its preparation method and application - Google Patents

Abstract

The invention provides a special surface sizing agent for corrugated paper and its preparation method and application. The components and weight fractions of the special surface sizing agent for corrugated paper are as follows: 100 parts of surface sizing agent base material for corrugated paper, 5 parts of sodium bentonite dispersion ~10 parts, the components and weight fractions of the sodium-based bentonite dispersion are as follows: 100 parts of sodium-based bentonite, 0.2-1 part of acidic dispersant, 100 parts of zirconium beads, 150-240 parts of water, and the acidic dispersant is sodium polyacrylate aqueous solution . The special surface sizing agent for corrugated paper of the invention is a high-performance and environment-friendly product that can meet the surface sizing requirements of paper. This product can be used together with starch to sizing the surface of corrugated base paper, which can not only significantly improve the Cobb value, accelerate the curing speed, but also greatly increase the ring compressive strength of corrugated paper, reduce the amount of starch used, and can meet the needs of the development of high-strength corrugated paper.

Description

Special surface sizing agent for corrugated paper and its preparation method and application

technical field

The invention relates to a special surface sizing agent for corrugated paper.

Background technique

The development trend of paper, especially corrugated paper and cardboard is as follows:

1) It is developing from high grammage to low grammage.

2) Use waste paper instead of wood pulp, but the strength of the paper is poor and the water absorption value is high.

3) Due to the unstable quality of paper caused by many variable factors in internal sizing, and the difficulty of improving the grade, it has become a popular trend for manufacturers to use less or abandon internal sizing and use surface sizing to make up for it.

Requirements for the sizing agent used for the above-mentioned surface sizing: a) increase the ring compressive strength; b) greatly reduce the Cobb value (water absorption value); c) fast curing speed, and it is required to be cooked immediately after getting off the machine.

However, although the current surface sizing agent can improve the ring crush strength of corrugated paper, the amount of sizing agent is large and the cost is high.

A kind of sizing agent disclosed in Chinese patent CN 101148842A, although the curing speed is fast and does not return to moisture, it does not improve the ring compression strength of corrugated paper much.

Contents of the invention

The object of the present invention is to propose a special surface sizing agent for corrugated paper and its preparation method and application, so as to overcome the above-mentioned defects in the prior art.

The special surface sizing agent for corrugated paper of the present invention is characterized in that the components and weight fractions are as follows: 100 parts of surface sizing agent base material for corrugated paper, 5 to 10 parts of sodium bentonite dispersion liquid, and the weight solid content is 20wt%～ 40wt%, pH=2～6;

The preparation method comprises the following steps:

Mix the surface sizing agent base material for corrugated paper, sodium bentonite dispersion and deionized water to obtain a special surface sizing agent for corrugated paper;

The surface sizing agent base material for corrugated paper, its preparation method, comprises the following steps:

The cationic monomer, cross-linking monomer, (meth)acrylate monomer, (methyl) styrene, dispersant, emulsifier and initiator are subjected to free radical emulsion polymerization at 40°C to 95°C ,, the reaction time is 2-8 hours, and the surface sizing agent base material for corrugated paper is obtained, the pH=2-6, and the weight solid content is 20wt%-40wt%.

In the reaction system, the components and weight fractions are as follows:

Cationic monomer 3～8 parts

Cross-linking monomer 1～5 parts

(meth)acrylate monomer 20-40 parts

(Methyl)styrene 100 parts

Dispersant 20～50 parts

Emulsifier 0.5～2 parts

Initiator 0.3～2 parts

Water 210～830 parts

Said cationic monomer is selected from at least one of dimethylaminoethyl acrylate monochloromethane quaternary ammonium, methacrylic acid acyloxyethyl trimethyl ammonium chloride or diallyl dimethyl ammonium chloride ;

Said crosslinking monomer is selected from hydroxypropyl acrylate, methacrylamide, acrylamide, N-methylolacrylamide, ethylene glycol diacrylate, divinylbenzene, glycidyl acrylate, methacrylic acid Glycidyl esters, N-butoxymethacrylate, aminoethyl acrylate, aminopropyl acrylate, dimethyl-isopropenylphenylisocyanate or propyl-methyl-diethoxysiloxane methacrylate at least one of

Said (meth)acrylate monomer is selected from methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, tert-butyl acrylate, isooctyl acrylate, methyl methacrylate At least one of ester, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate or isooctyl methacrylate;

Said dispersant is gelatin, the weight average molecular weight is 10000～100000g/mol;

Said emulsifier is a cationic surfactant, and the cationic surfactant is selected from at least one of C _12～18 alkyl polyoxyethylene (n=5～20) trimethyl ammonium chloride;

Said initiator is selected from at least one of potassium persulfate, ammonium persulfate or sodium persulfate;

The preparation method of said sodium bentonite dispersion comprises the following steps: putting an acidic dispersant, water, sodium bentonite and zirconium beads into a grinding jar, grinding and dispersing, and filtering to obtain a sodium bentonite dispersion;

The grinding and dispersing time is 4 to 6 hours, and the grinding speed is 600 to 800 rpm;

Said sodium bentonite dispersion liquid, in dispersion system, component and weight fraction are as follows:

Sodium bentonite 100 parts

Acidic dispersant 0.2～1 parts

Zirconium beads 100 parts

Water 150～240 parts

Said sodium bentonite can adopt commercially available products, such as the product of Xintiandi Mining Co., Ltd. in Henan Province;

The acidic dispersant is an aqueous sodium polyacrylate solution with a solid content of 40-60 wt%, a pH of 4-6, and a molecular weight of 3000-4000;

Said zirconia beads are a kind of zirconia beads (such as Japanese TOSOH zirconia beads, Shanghai Maocang Trading Co., Ltd.), which are used as grinding media;

The special surface sizing agent for corrugated paper can be used for surface treatment of corrugated base paper.

In the preparation method of the special surface sizing agent for corrugated paper of the present invention, the inventors found that adding sodium-based bentonite dispersion liquid to the base material of the surface sizing agent for corrugated paper can greatly improve the effect of surface sizing and enhance the ring compressive strength of corrugated paper. At the same time, it can reduce the Cobb value of corrugated paper. It is well known that adding inorganic substances to paper will reduce the strength of paper. However, adding sodium-based bentonite dispersion in the present invention can enhance the ring crush strength of corrugated paper, which may be due to the presence of a large amount of aluminum and magnesium ions in sodium-based bentonite, which can be combined with the hydroxyl groups of the surface fibers of corrugated paper, and can also be combined with starch in the corrugated paper. The combination of a large number of hydroxyl and carboxyl groups can strengthen the interaction between the corrugated paper surface sizing agent base material, fiber and starch, and can enhance the ring pressure strength of corrugated paper. Sodium bentonite itself has a certain degree of hydrophobicity, and the prepared sodium bentonite dispersion also inherits this property. Adding it to the sizing agent base material on the surface of corrugated paper can improve the hydrophobicity of the paper after sizing with the sizing agent and reduce the Cobb value of the paper.

The special surface sizing agent for corrugated paper of the invention is a high-performance and environment-friendly product that can meet the surface sizing requirements of paper. This product can be used together with starch to sizing the surface of corrugated base paper, which can not only significantly improve the Cobb value, accelerate the curing speed, but also greatly increase the ring compressive strength of corrugated paper, reduce the amount of starch used, and can meet the needs of the development of high-strength corrugated paper.

Detailed ways

Example 1

(1) Preparation of surface sizing agent base material for corrugated paper:

In a 1000ml four-necked flask equipped with a condenser, a dropping device, a stirrer and a thermometer, add 20 grams of gelatin with a molecular weight of 10000 g/mol and 214.5 grams of deionized water, heat up to 85°C to dissolve, then cool down to 45°C. Add 2 grams of 25wt% octadecyl polyoxyethylene (15) trimethylammonium chloride aqueous solution, heat to 95°C, add 1.5 grams of 20wt% ammonium persulfate aqueous solution, and add the following mixed monomers dropwise:

100 grams of styrene, 3 grams of dimethylaminoethyl acrylate monochloromethane quaternary ammonium, 1 gram of N-butoxymethacrylic acid, and 20 grams of n-butyl acrylate were added in 1 hour. The reaction was maintained at 95°C for 1 hour, cooled to 35°C, pH = 2.0. Filter through a 100-mesh filter to obtain a surface sizing agent base material for corrugated paper, with a solid content of 39.9 wt%.

(2) Preparation of sodium bentonite dispersion:

Add 100g of zirconium beads (Japanese TOSOH zirconia beads, Shanghai Maocang Trading Co., Ltd.), 0.2g of sodium polyacrylate aqueous solution (solid content is 40wt%, molecular weight is 3000, pH=4) and 150.3g of deionized water into a 1L grinding jar , put the grinding jar, start the grinder, and turn the grinding speed at 600 rpm, then add 100g of sodium bentonite to the grinding jar, and grind and disperse for 4 hours. Filter through a 200-mesh stainless steel screen to obtain a sodium-based bentonite dispersion with a solid content of 40.2 wt%.

(3) Preparation of special surface sizing agent for corrugated paper:

Add 200 g of the surface sizing agent base material for corrugated paper prepared in step 1 and 10 g of the sodium-based bentonite dispersion prepared in step 2 into a 1000 ml four-neck flask for mixing, and stir for 10 minutes. A special surface sizing agent for corrugated paper was prepared, with a solid content of 39.8 wt % and a pH of 2.1.

Example 2

(1) Preparation of surface sizing agent base material for corrugated paper:

Add 50 grams of gelatin with a molecular weight of 100,000 g/mol and 808 grams of deionized water into a 2000ml four-neck flask equipped with a condenser, a dropping device, a stirrer, and a thermometer, heat up to 85°C to dissolve, and cool down to 45°C. Add 20 grams of 10wt% lauryl polyoxyethylene (20) trimethylammonium chloride aqueous solution, add 4 grams of 50wt% potassium persulfate aqueous solution, and drop the following mixed monomers: 100 grams of methyl styrene, methacrylic acid 8 grams of acyloxyethyltrimethylammonium chloride, 5 grams of divinylbenzene, and 40 grams of isooctyl methacrylate were added in 6 hours. The reaction was maintained at 40°C for 2 hours, cooled to 25°C, pH=5.85. Filter through a 100-mesh filter to obtain a surface sizing agent base material for corrugated paper, with a solid content of 20.1 wt%.

(2) Preparation of sodium bentonite dispersion:

圣戈班集团西普公司)、1g聚丙烯酸钠水溶液(固含量为45wt％，分子量为4000，pH＝6)和235.7g去离子水加入1L研磨罐中，将研磨罐装好，开动研磨机，转磨转速800转/分钟，再向研磨罐中加入100g钠基膨润土，研磨分散6小时。采用200目不锈钢筛网过滤，得到钠基膨润土分散液，固含量：30.1wt％。100g zirconium beads (zirconia beads

Saint-Gobain Group Xipu Company), 1g sodium polyacrylate aqueous solution (solid content is 45wt%, molecular weight is 4000, pH=6) and 235.7g deionized water are added in the 1L grinding pot, the grinding pot is packed, start the grinder, turn The milling speed was 800 rpm, and then 100 g of sodium bentonite was added to the grinding tank, and ground and dispersed for 6 hours. Filter through a 200-mesh stainless steel screen to obtain a sodium-based bentonite dispersion, with a solid content of 30.1 wt%.

(3) Preparation of special surface sizing agent for corrugated paper:

Add 200 g of the surface sizing agent base material for corrugated paper prepared in step 1, 20 g of the sodium bentonite dispersion prepared in step 2, and 10 g of deionized water into a 1000 ml four-neck flask for mixing, and stir for 10 minutes. A special surface sizing agent for corrugated paper was prepared with a solid content of 20.15 wt % and a pH of 5.89.

Example 3

(1) Preparation of surface sizing agent base material for corrugated paper:

In a 1000ml four-neck flask equipped with a condenser, a dropping device, a stirrer and a thermometer, add 35 grams of gelatin with a molecular weight of 80000g/mol and 395.3 grams of distilled water, and heat up to 85°C to dissolve. Cool down to 45°C. Add 10 grams of 10 wt% tetradecyl polyoxyethylene (8) trimethylammonium chloride aqueous solution, heat to 60 ° C, add 5 grams of 20 wt % sodium persulfate aqueous solution, and drop the following mixed monomers: 100 grams of styrene, 5 grams of diallyl dimethyl ammonium chloride, 3 grams of aminoethyl acrylate, and 30 grams of methyl methacrylate were added in 4 hours. The reaction was maintained at 60°C for 2 hours, cooled to 35°C, pH = 3.5. Filter through a 100-mesh filter to obtain a surface sizing agent base material for corrugated paper, with a solid content of 30.2 wt%.

(2) Preparation of sodium bentonite dispersion:

圣戈班集团西普公司)、0.5g聚丙烯酸钠水溶液(固含量为52wt％。分子量：3500，pH＝5)和186.64g去离子水加入1L研磨罐中，将研磨罐装好，开动研磨机，转磨转速700转/分钟，再向研磨罐中加入100g钠基膨润土，研磨分散5小时。采用200目不锈钢筛网过滤，得到钠基膨润土分散液，固含量：34.9wt％。100g zirconium beads (zirconia beads

Saint-Gobain Group Xipu Company), 0.5g sodium polyacrylate aqueous solution (solid content is 52wt%. Molecular weight: 3500, pH=5) and 186.64g deionized water add in the 1L grinding tank, the grinding tank is packed, start the grinder, The rotation speed of the mill was 700 rpm, and then 100 g of sodium bentonite was added to the grinding jar, and the mixture was ground and dispersed for 5 hours. Filter through a 200-mesh stainless steel screen to obtain a sodium-based bentonite dispersion with a solid content of 34.9 wt%.

(3) Preparation of special surface sizing agent for corrugated paper:

Add 200 g of surface sizing agent base material for corrugated paper prepared in step 1, 15 g of sodium bentonite dispersion prepared in step 2, and 2.5 g of deionized water into a 1000 ml four-neck flask and mix for 10 minutes. A special surface sizing agent for corrugated paper was prepared, with a solid content of 30.1 wt % and a pH of 3.80.

Example 4

(1) Preparation of surface sizing agent base material for corrugated paper:

In a 1000ml four-necked flask equipped with a condenser, a dropping device, a stirrer and a thermometer, add 30 grams of gelatin with a molecular weight of 50000 and 495.6 grams of deionized water, and heat up to 85°C to dissolve. Cool down to 35°C. Add 6 grams of 25wt% octadecyl polyoxyethylene (5) trimethylammonium chloride aqueous solution, heat to 70°C, add 1.4 grams of 50wt% ammonium persulfate aqueous solution, and drop the following mixed monomers: Methylstyrene 100 gram, 3 grams of dimethylaminoethyl acrylate monochloromethane quaternary ammonium, 3 grams of acyloxyethyl trimethyl ammonium chloride, 2 grams of N-methylol acrylamide, 25 grams of ethyl methacrylate , 3 hours added. The reaction was maintained at 70°C for 1 hour, cooled to 35°C, pH = 4.5. Filter through a 100-mesh filter to obtain a surface sizing agent base material for corrugated paper, with a solid content of 25.2 wt%.

(2) Preparation of sodium bentonite dispersion:

Add 100g of zirconium beads (Japanese TOSOH zirconia beads, Shanghai Maocang Trading Co., Ltd.), 0.8g of sodium polyacrylate aqueous solution (solid content: 58wt%, molecular weight: 3800, pH=5) and 164.46g of deionized water into a 1L grinding jar , put the grinding tank, start the grinder, and turn the grinding speed to 750 rpm, then add 100g of sodium bentonite to the grinding tank, and grind and disperse for 5.5 hours. Filter through a 200-mesh stainless steel screen to obtain a sodium-based bentonite dispersion, with a solid content of 37.85 wt%.

(3) Preparation of special surface sizing agent for corrugated paper:

Add 200 g of surface sizing agent base material for corrugated paper prepared in step 1, 18 g of sodium bentonite dispersion prepared in step 2 and 9.36 g of deionized water into a 1000 ml four-neck flask and mix for 10 minutes. A special surface sizing agent for corrugated paper was prepared, with a solid content of 24.8wt% and a pH of 4.3.

Example 5

(1) Preparation of surface sizing agent base material for corrugated paper:

In a 1000ml four-neck flask equipped with a condenser, a dropping device, a stirrer and a thermometer, add 40 grams of gelatin with a molecular weight of 20000 and 397.8 grams of distilled water, and heat up to 85°C to dissolve. Cool down to 35°C. Add 3.2 grams of 25wt% cetyl polyoxyethylene (10) trimethyl ammonium chloride aqueous solution, heat to 80°C, add 3 grams of 50wt% potassium persulfate aqueous solution, add dropwise the following mixed monomers: 100 grams of styrene, 4 grams of diallyl dimethyl ammonium chloride, 4 grams of ethylene glycol diacrylate, and 35 grams of methyl acrylate were added in 2 hours. The reaction was maintained at 80°C for 1 hour, cooled to 35°C, pH=4.1. Filter through a 100-mesh filter screen to obtain a surface sizing agent base material for corrugated paper, with a solid content of 35.4 wt%.

(2) Preparation of sodium bentonite dispersion:

Add 100g of zirconium beads (Japanese TOSOH zirconia beads, Shanghai Mocang Trading Co., Ltd.), 0.4g of sodium polyacrylate aqueous solution (solid content: 55wt%, molecular weight: 3300, pH=5) and 186.4g of deionized water into a 1L grinding jar , put the grinding tank, start the grinder, and turn the grinding speed at 650 rpm, then add 100g of sodium bentonite to the grinding tank, and grind and disperse for 4.5 hours. Filter through a 200-mesh stainless steel screen to obtain a sodium-based bentonite dispersion, with a solid content of 34.95 wt%.

(3) Preparation of special surface sizing agent for corrugated paper:

Add 200 g of the surface sizing agent base material for corrugated paper prepared in step 1 and 12 g of the sodium bentonite dispersion prepared in step 2 into a 1000 ml four-neck flask for mixing, and stir for 10 minutes. A special surface sizing agent for corrugated paper was prepared, with a solid content of 34.87wt% and a pH of 3.8.

Example 6

Surface sizing on corrugated paper:

Comparative example: the sizing agent prepared according to the method of Chinese patent CN101148842A has a solid content of 20 wt%.

The sizing agent prepared by the formula of Examples 1-5 is diluted to 20wt% with deionized water

The preparation of sizing solution: prepare 500 grams of 10wt% oxidized starch aqueous solution, be warming up to 90 ℃, gelatinize 20 minutes, cool down to 40 ℃, add the sizing agent (oxidized starch (oxidized starch ( dry): sizing agent (wet) = 50:4), and diluted with water to 8wt%.

Cobb value determination:

The paper sample to be tested was detected by the XSH type Kebo absorbency tester of Hangzhou Qingtong Boke Automation Technology Co., Ltd. according to the method of GB/T1540-1989.

Determination of ring compressive strength:

The paper sample to be tested was detected by the CT300A compressive strength tester of Hangzhou Qingtong Boke Automation Technology Co., Ltd.

Surface sizing on corrugated paper:

Use the sizing solution formulated in the comparative example and Examples 1 to 5 to coat 120 grams of corrugated base paper with a 10# coating rod, and the coating amount is 2 g/m ² , and bake in an oven at 110 ° C after coating 30 seconds or 120 seconds, take it out, cool to room temperature for measurement.

It can be seen from the above application results that the sizing agents prepared in Examples 1 to 5 of the present invention can greatly increase the ring crush strength of paper and significantly improve the Cobb value compared with the comparative examples.

Claims (6)

1. surface sizing agent special for corrugated paper is characterized in that, each component and weight fraction are as follows: 100 parts of Cypres base-materials of corrugated paper, and 5～10 parts of sodium bentonite dispersion liquids, the component and the weight fraction of said sodium bentonite dispersion liquid are as follows:

100 parts of sodium bentonites

0.2～1 part of acid dispersant

100 parts on zirconium pearl

150～240 parts in water

Said acid dispersant is the polyacrylic acid sodium water solution.

2. surface sizing agent special for corrugated paper according to claim 1 is characterized in that, polyacrylic acid sodium water solution solid content is 40～60wt%, pH=4～6, and molecular weight is 3000～4000.

3. surface sizing agent special for corrugated paper according to claim 1, it is characterized in that, described corrugated paper Cypres base-material, its preparation method, may further comprise the steps: with cationic monomer, cross-linking monomer, (methyl) acrylic ester monomer, (methyl) styrene, dispersant, emulsifying agent and initator, under 40 ℃～95 ℃ conditions, carry out free-radical emulsion polymerization, reaction time is 2～8 hours, obtain corrugated paper Cypres base-material, pH=2～6, weight solid content 20wt%～40wt%.

4. surface sizing agent special for corrugated paper according to claim 3 is characterized in that,

3～8 parts of cationic monomers

1～5 part of cross-linking monomer

20～40 parts of (methyl) acrylic ester monomers

100 parts of (methyl) styrene

20～50 parts of dispersants

0.5～2 part of emulsifying agent

0.3～2 part of initator

210～830 parts in water

Said cationic monomer is selected from least a in acrylic acid dimethylamino ethyl ester monochloro methane quaternary ammonium, methacrylic acid acyl-oxygen ethyl-trimethyl salmiac or the diallyldimethylammonium chloride;

Said cross-linking monomer is selected from least a in isopropenyl phenyl isocyanate between hydroxypropyl acrylate, Methacrylamide, acrylamide, N hydroxymethyl acrylamide, two acrylic acid glycol ester, divinylbenzene, glycidyl acrylate, glycidyl methacrylate, N-fourth oxygen methacrylic acid, acrylic-amino ethyl ester, acrylic-amino propyl ester, dimethyl or the methacrylic acid propyl group-methyl-diethoxy siloxanes;

Said (methyl) acrylic ester monomer is selected from least a in methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, tert-butyl acrylate, Isooctyl acrylate monomer, methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-BMA, isobutyl methacrylate, metering system tert-butyl acrylate or the EHMA;

Said dispersant is a gelatin, and weight average molecular weight is 10000～100000g/mol;

Said emulsifying agent is a cationic surfactant, and cationic surfactant is selected from C _12～18At least a in alkyl polyoxyethylene (n=5～20) trimethyl ammonium chloride;

Said initator is selected from least a in potassium peroxydisulfate, ammonium persulfate or the sodium peroxydisulfate.

5. the method for preparing each described surface sizing agent special for corrugated paper of claim 1～4, it is characterized in that, comprise the steps: corrugated paper is mixed with Cypres base-material, sodium bentonite dispersion liquid and deionized water, promptly obtain surface sizing agent special for corrugated paper.

6. according to the application of each described surface sizing agent special for corrugated paper of claim 1～4, it is characterized in that, be used for the surface treatment of fluting medium.