阅读说明：本技术 一种造纸用表面施胶剂制备方法 (Preparation method of surface sizing agent for papermaking ) 是由 胡新仿 于 2020-05-23 设计创作，主要内容包括：本发明公开了一种造纸用表面施胶剂制备方法,包括以下步骤:在高剪切釜内加入温度为70-75℃的热水,搅拌状态下加入稳定剂、分散剂、聚酰胺树脂和高聚物复合乳化剂,搅拌均匀后升温至80℃；将AKD蜡粉跟精炼石蜡混合后加入熔化釜,加热至75-78℃,熔化成蜡油加入高剪切釜内,经混合后的乳液由高剪切釜输送至循环釜后再返回高剪切釜,将循环后的乳液连续通过高压均质机均质两次,将均质后的乳液经换热器冷却后加入超声波反应釜中,搅拌均匀后静置25-35分钟后得到成品。本发明采用复合乳化剂取代原有的淀粉乳化剂,改进乳化工艺,以此制得的乳液稳定性好,不易水解。该工艺不仅极大地提高了施胶剂施胶效率和抗水性能,同时还可以防止纸张返潮。(The invention discloses a preparation method of a surface sizing agent for papermaking, which comprises the following steps of adding hot water with the temperature of 70-75 ℃ into a high-shear kettle, adding a stabilizer, a dispersant, polyamide resin and a high polymer composite emulsifier under the stirring state, uniformly stirring, and heating to 80 ℃; mixing AKD wax powder and refined paraffin, adding the mixture into a melting kettle, heating the mixture to 75-78 ℃, melting the mixture into wax oil, adding the wax oil into a high-shear kettle, conveying the mixed emulsion from the high-shear kettle to a circulating kettle, returning the mixed emulsion to the high-shear kettle, continuously homogenizing the circulating emulsion twice through a high-pressure homogenizer, cooling the homogenized emulsion through a heat exchanger, adding the cooled emulsion into an ultrasonic reaction kettle, uniformly stirring, and standing for 25-35 minutes to obtain a finished product. The invention adopts the compound emulsifier to replace the original starch emulsifier, improves the emulsification process, and ensures that the prepared emulsion has good stability and is not easy to hydrolyze. The process not only greatly improves the sizing efficiency and the water resistance of the sizing agent, but also can prevent the paper from getting damp.)

1. The preparation method of the surface sizing agent for papermaking is characterized by comprising the following steps:

a. mixing 350Kg of AKD wax powder and refined paraffin wax, adding the mixture into a melting kettle, heating to 75-78 ℃, and melting into wax oil for later use;

b. adding 450-550Kg of hot water at the temperature of 70-75 ℃ into a high-shear kettle, adding 10-12Kg of stabilizer, 5-8Kg of dispersant, 50-80Kg of polyamide resin and 100-150Kg of high polymer composite emulsifier under the stirring state, uniformly stirring, and then heating to 80 ℃;

c. adding the melted wax oil for standby use into a high-shear kettle under the stirring state, conveying the mixed emulsion from the high-shear kettle to a circulating kettle, returning to the high-shear kettle, and circulating for multiple times until the liquid level has no oil stains;

d. continuously homogenizing the circulated emulsion twice by a high-pressure homogenizer at the homogenizing pressure of 20-25 Mpa;

e. cooling the homogenized emulsion by a heat exchanger, adding the cooled homogenized emulsion into an ultrasonic reaction kettle, starting ultrasonic and magnetic stirring, adding 50ml of 6-hydroxy-2- [ [ [ (1-hydroxy-6-oxo-2-cyclohexenyl) carbonyl ] oxy ] methyl ] phenyl-beta-D glucoside and 1-3Kg of defoaming agent, adding water to adjust the solid content, uniformly stirring, and standing for 25-35 minutes to obtain a finished product.

2. The method as claimed in claim 1, wherein the AKD wax powder content in step a is 260Kg and the refined paraffin wax content is 70-120 Kg.

3. The method of claim 1, wherein the stabilizer in step b is zirconium oxychloride.

4. The method for preparing a surface sizing agent for papermaking according to claim 1, wherein the high polymer composite emulsifier in the step b is a composition of polydimethyl diallyl ammonium chloride and modified polysaccharide.

5. The method for preparing a surface sizing agent for papermaking according to claim 1, wherein the high polymer composite emulsifier in the step b is a combination of polydimethydiallylammonium chloride and styrene copolymer.

6. The method of claim 1, wherein the first homogenizing pressure is 25Mpa, and the second homogenizing pressure is 20 Mpa.

7. The method of claim 4, wherein the weight ratio of the polydimethyidiallylammonium chloride: the mass ratio of the modified polysaccharide is 3: 1.

8. The method of claim 5, wherein the mass ratio of the poly (dimethyldiallylammonium chloride) to the styrene copolymer is 2: 1.

9. The method for preparing a surface sizing agent for papermaking according to claim 1, characterized in that the operating frequency of the ultrasonic reaction kettle is 20KHz, and the power is 1200W.

Technical Field

The invention relates to the field of papermaking, in particular to a preparation method of a surface sizing agent for papermaking.

Background

Surface sizing is to coat a layer of sizing agent on the surface of paper and paperboard, which is generally coated by taking starch as a carrier, and the surface properties of the paper subjected to surface sizing treatment can be changed, so that various application properties of the paper are obviously improved. With the development of the papermaking technology, and based on comprehensive consideration of various aspects such as energy, environment and the like, the papermaking conditions of the modern papermaking industry are obviously changed, and the papermaking environment is more severe and harsh; in addition, with the improvement of living standard, the quality requirement of people on paper is continuously improved, so that higher requirements are put forward on the development and application of related papermaking chemicals. In particular, for the production of various papers and paperboards, the performance requirements of surface sizing agents for papermaking are increasing in order to obtain higher performance products. The surface of paper and paperboard is coated with a layer of sizing agent, which is generally coated by taking starch as a carrier, and the surface properties of the paper subjected to surface sizing treatment can be changed, so that various application performances of the paper are obviously improved. With the development of the papermaking technology, and based on comprehensive consideration of various aspects such as energy, environment and the like, the papermaking conditions of the modern papermaking industry are obviously changed, and the papermaking environment is more severe and harsh; in addition, with the improvement of living standard, the quality requirement of people on paper is continuously improved, so that higher requirements are put forward on the development and application of related papermaking chemicals. In particular, for the production of various papers and paperboards, the performance requirements of surface sizing agents for papermaking are increasing in order to obtain higher performance products.

The excellent sizing agent can reduce sizing cost, improve paper performance and ensure paper quality, but the use of the existing surface sizing agent is not satisfactory due to the problems of components and preparation methods, so the improvement and innovation are technical problems which need to be solved.

Disclosure of Invention

In view of the above situation, the present invention aims to overcome the defects of the prior art, and the present invention provides a method for preparing a surface sizing agent for papermaking, which can effectively improve the sizing efficiency and the water resistance of the sizing agent, and can prevent paper from getting damp.

The technical scheme of the invention is as follows: a preparation method of a surface sizing agent for papermaking comprises the following steps:

a. mixing 350Kg of AKD wax powder and refined paraffin wax, adding the mixture into a melting kettle, heating to 75-78 ℃, and melting into wax oil for later use;

b. adding 450-550Kg of hot water at the temperature of 70-75 ℃ into a high-shear kettle, adding 10-12Kg of stabilizer, 5-8Kg of dispersant, 50-80Kg of polyamide resin and 100-150Kg of high polymer composite emulsifier under the stirring state, uniformly stirring, and then heating to 80 ℃;

c. adding the melted wax oil for standby use into a high-shear kettle under the stirring state, conveying the mixed emulsion from the high-shear kettle to a circulating kettle, returning to the high-shear kettle, and circulating for multiple times until the liquid level has no oil stains;

d. continuously homogenizing the circulated emulsion twice by a high-pressure homogenizer at the homogenizing pressure of 20-25 Mpa;

e. cooling the homogenized emulsion by a heat exchanger, adding the cooled homogenized emulsion into an ultrasonic reaction kettle, starting ultrasonic and magnetic stirring, adding 50ml of 6-hydroxy-2- [ [ [ (1-hydroxy-6-oxo-2-cyclohexenyl) carbonyl ] oxy ] methyl ] phenyl-beta-D glucoside and 1-3Kg of defoaming agent, adding water to adjust the solid content, uniformly stirring, and standing for 25-35 minutes to obtain a finished product.

Furthermore, the content of AKD wax powder in the step a is 230-260Kg, and the content of refined paraffin is 70-120 Kg.

Further, the stabilizer in the step b is zirconium oxychloride.

Further, the polymer composite emulsifier in the step b is a composition of polydimethyl diallyl ammonium chloride and modified polysaccharide.

Further, the polymer composite emulsifier in the step b is a composition of polydimethyl diallyl ammonium chloride and a styrene copolymer.

Further, the first homogenizing pressure is 25Mpa, and the second homogenizing pressure is 20 Mpa.

Further, the polydimethyldiallylammonium chloride in step b: the mass ratio of the modified polysaccharide is 3: 1.

Further, the mass ratio of the polydimethyl diallyl ammonium chloride to the styrene copolymer in the step b is 2: 1.

Furthermore, the working frequency of the ultrasonic reaction kettle is 20KHz, and the power is 1200W.

The invention has the following advantages: the preparation method of the surface sizing agent provided by the invention has the advantages that the composite emulsifier is adopted to replace the original starch emulsifier in the preparation method, the emulsification process is improved, and the prepared emulsion has good stability and is not easy to hydrolyze. The process not only greatly improves the sizing efficiency and the water resistance of the sizing agent, but also can prevent the paper from getting damp.

Detailed Description

The present invention will be described in detail with reference to the following embodiments in order to make the aforementioned objects, features and advantages of the invention more comprehensible.