CN108949022A - A kind of biology latex, biological latex paint and its preparation method and application - Google Patents

Abstract

The present invention provides a kind of biological latex, biological latex paint and its preparation method and application.Biology latex of the present invention, prepares the component that raw material includes following parts by weight: 100 parts of starch, 10~50 parts of water, 5~50 parts of glycerine, 1~20 part of sodium hydroxide, 1~30 part of methoxypolyethylene glycol-carboxylic acid.Coating of the present invention includes following components: biological latex, pigment, auxiliary agent.Coating of the present invention is applied to field of papermaking, surface strength can be produced and increased, the excellent paper of gloss；The usage amount of petroleum base latex can be reduced, to reduce the cost of coating in papermaking coating process, while harmful substance contents in coating paper is reduced, expands the range of package paper, meet the requirement of environmental protection.

Description

A kind of biological latex, biological latex coating and its preparation method and application

technical field

The invention belongs to the field of latex paint, and in particular relates to biological latex, biological latex paint, a preparation method and application thereof.

Background technique

With the development of social economy, the market has higher and higher requirements for coated paper and related paper products. Among them, the styrene-butadiene latex and styrene-acrylic latex synthesized from petroleum cracking products are gradually replaced because they contain benzene residues that are harmful to the human body and the environment. At the same time, due to the depletion of petroleum resources, the cost of such latex is gradually increasing. The cost of products is also increased accordingly, which limits the development of papermaking and coating industries.

Starch is a natural polysaccharide that exists widely in nature. Its low cost and environmental protection characteristics have made many paper companies turn to the research on bio-latex. The starch is modified by physical, chemical and biological methods, and the obtained bio-latex has the advantages of high solid content, low viscosity, good stability and uniform particle size. At the same time, the reaction extrusion method is adopted, which is easy to operate, high in efficiency and short in cycle, and can obtain starch-based bio-latex more conveniently. It can be used in conjunction with other pigment additives, etc., to obtain an environmentally friendly bio-latex paint for papermaking that is cheap and has a good coating effect.

Chinese patent CN102300908 A and U.S. patent US2010143738 disclose a preparation method of biological latex, and obtain a biological latex with a core-shell structure. Water binds better, which affects paper quality. Therefore, it is of great significance to provide a biological latex coating with a small number of surface hydroxyl groups, low water absorption, and no influence on paper quality during coating.

Contents of the invention

In order to solve the shortcomings and deficiencies of the prior art, the primary purpose of the present invention is to provide a biological latex and a preparation method thereof.

Another object of the present invention is to provide a coating prepared from the above biological latex and a preparation method thereof.

Another object of the present invention is to provide the application of the above coating.

In order to reduce the number of hydroxyl groups on the surface of the starch-based biological latex, the present invention uses methoxyl-polyethylene glycol-carboxylic acid modified starches with different molecular weights. Under alkaline conditions, the carboxyl group reacts with the hydroxyl group in the starch to reduce the number of hydroxyl groups. At the same time, the presence of long-chain PEG (polyethylene glycol) can reduce the interaction of hydrogen bonds in the starch molecule, making it more efficient during extrusion. In the process, a smaller and more uniform size bio-latex is obtained, and then combined with other pigments and additives to obtain an environmentally friendly paper-making coating.

The object of the present invention is achieved through the following technical solutions:

A biological latex, characterized in that the preparation raw materials include the following components in parts by weight: 100 parts of starch, 10 to 50 parts of water, 5 to 50 parts of glycerol, 1 to 20 parts of sodium hydroxide, methoxy- 1-30 parts of polyethylene glycol-carboxylic acid.

Preferably, the molecular weight of the methoxy-polyethylene glycol-carboxylic acid is 550-20000, more preferably, the molecular weight of the methoxy-polyethylene glycol-carboxylic acid is 550, 1000, 2000, 5000, One or more of 10000 and 20000, the starch is one or more of corn starch, waxy corn starch, potato starch, wheat starch and tapioca starch.

The preparation method of the above-mentioned biological latex comprises the following steps: uniformly mixing starch with methoxy-polyethylene glycol-carboxylic acid, sodium hydroxide, water, and glycerin, then putting it into a twin-screw extruder, and reacting The biological latex is obtained by extrusion, wherein the temperature of the feeding section of the extruder is 30-100° C., the screw speed is 40-500 rpm, and the temperature of the material heating extrusion section is 50-300° C.

A biological latex paint, comprising the following components in parts by mass: 10-30 parts of the above-mentioned biological latex, 50-80 parts of pigments, and 1-20 parts of auxiliary agents.

Preferably, the pigment is one or more of kaolin, calcium carbonate, barium carbonate, talcum powder, aluminum hydroxide, zinc oxide, and wrought white powder.

Preferably, the auxiliary agent is one or two or more of defoamers, lubricants, dispersants, thickeners, and water-resistant agents.

Preferably, the lubricant is one or more of sodium stearate, potassium stearate, ammonium stearate, paraffin, calcium oleate, polyethylene glycol, soybean lecithin, and the The dispersant is one or more of sodium hexametaphosphate, sodium pyrophosphate, sodium tetrapolyphosphate, sodium polymethacrylate and polyvinyl alcohol.

Preferably, the thickener is one or more of methyl cellulose, sodium carboxymethyl cellulose, and polyacrylic acid, and the water-resistant agent is melamine formaldehyde resin, ammonium zirconium carbonate, polyamide One or more of polyurea resins, and the defoamer is one or more of polydimethylsiloxane, octanol, tripropyl phosphate, and tributyl phosphate.

The preparation method of the above-mentioned bio-latex paint is characterized in that it comprises the following steps: uniformly mixing the bio-latex, pigments and auxiliary agents in parts by mass to obtain the bio-latex paint. The application of the above-mentioned bio-latex coating in the primer and intermediate coating process of the papermaking industry.

Compared with the prior art, the present invention has the following advantages and beneficial effects:

(1) Replacing some petroleum derivatives with starch and its derivatives can reduce the amount of petroleum derivatives, reduce the production cost of latex, and help protect the environment.

(2) Compared with existing starch-based bio-latex, the present invention adopts the long-chain PEG containing terminal carboxyl groups to carry out esterification with the hydroxyl in starch, reduces the number of hydroxyl in the starch molecule, and avoids the bio-latex coating of many hydroxyl groups When the paper is subsequently coated, the water absorption is enhanced, which adversely affects the paper gloss, folding resistance, water resistance, etc., and achieves the purpose of improving the water resistance of starch-based bio-latex.

Detailed ways

Example 1

Starch-based biological latex preparation method: 100g starch (Aladdin), 30g water, 5g glycerol (Aladdin), 10g methoxy-polyethylene glycol-carboxylic acid (molecular weight is 550, Xi'an Kaixin Biotechnology Co., Ltd. company) and 8g sodium hydroxide (Aladdin), put them into a mixer (Shanghai Shihe Electromechanical Equipment Co., Ltd., SGB-S450 mixer), stir and mix for 2 hours, and put the obtained uniform material into a twin-screw extruder (Dongguan Shihe Yan Precision Instrument Co., Ltd., SY-6217-B), the set speed is 80rpm, the temperature of the feeding section is 50°C, the temperature of the material heating section is 120°C, and the temperature of the conveying section is 100°C.

Get 10g above-mentioned biological latex that makes, add 80g calcium carbonate (Aladdin), 3g octanol (Aladdin), 0.5g soybean lecithin (Aladdin), 7g sodium pyrophosphate (Aladdin), 2g polyacrylic acid (Aladdin) Latin), 5g polyamide polyurea resin (Qingzhou Dehai Fine Chemical Factory), mix uniformly to get coating.

Example 2

Starch-based biological latex preparation method: 100g starch (Aladdin), 25g water, 10g glycerol (Aladdin), 10g methoxy-polyethylene glycol-carboxylic acid (molecular weight is 1000, Xi'an Kaixin Biotechnology Co., Ltd. company) and 8g sodium hydroxide (Aladdin), put into high-speed mixer (same as embodiment 1), mix the homogeneous material that 2h obtains, put into twin-screw extruder (Dongguan Shiyan Precision Instrument Co., Ltd., SY Extrusion in -6217-B), the set speed is 90rpm, the temperature of the feeding section is 50°C, the temperature of the material heating section is 120°C, and the temperature of the conveying section is 100°C.

Take 10g of the above biological latex, add 80g kaolin (Aladdin), 3g silicone oil, 0.5g sodium stearate (Aladdin), 5g sodium hexametaphosphate (Aladdin), 2g methylcellulose (Aladdin), 3g melamine Formaldehyde resin (Jinan Dahui Chemical Technology Co., Ltd.), mix evenly to get the coating.

Example 3

Starch-based biological latex preparation method: 100g starch (Aladdin), 30g water, 10g glycerol (Aladdin), 10g methoxy-polyethylene glycol-carboxylic acid (molecular weight is 2000, Xi'an Kaixin Biotechnology Co., Ltd. company) and 10g sodium hydroxide (Aladdin), put into high-speed mixer (same as embodiment 1), mix the homogeneous material that 2h obtains, put into twin-screw extruder (Dongguan Shiyan Precision Instrument Co., Ltd., SY Extrusion in -6217-B), the set speed is 90rpm, the temperature of the feeding section is 50°C, the temperature of the material heating section is 120°C, and the temperature of the conveying section is 110°C.

Take 15g of the above biological latex, add 60g barium carbonate (Aladdin), 4g tributyl phosphate (Aladdin), 0.5g ammonium stearate (Aladdin), 4g polyvinyl alcohol (Aladdin), 3g carboxymethyl fiber Prime (Aladdin), 4g melamine formaldehyde resin (Jinan Dahui Chemical Technology Co., Ltd.), mix evenly and get coating.

Example 4

Starch-based biological latex preparation method: 100g starch (Aladdin), 35g water, 5g glycerol (Aladdin), 10g methoxy-polyethylene glycol-carboxylic acid (molecular weight is 10000, Xi'an Kaixin Biotechnology Co., Ltd. company) and 10g sodium hydroxide (Aladdin), put into high-speed mixer (same as embodiment 1), mix the homogeneous material that 2h obtains, put into twin-screw extruder (Dongguan Shiyan Precision Instrument Co., Ltd., SY -6217-B), where the set speed is 80rpm, the temperature of the feeding section is 50°C, the temperature of the material heating section is 130°C, and the temperature of the conveying section is 110°C.

Take 15g of the above biological latex, add 60g talcum powder (Aladdin), 5g tripropyl phosphate (Aladdin), 0.5g calcium oleate (Beijing Jingzewang Chemical Co., Ltd.), 5g sodium polymethacrylate (Aladdin) , 2g polyacrylic acid (Aladdin), 5g ammonium zirconium carbonate (Shanghai Titan Technology Co., Ltd.), mix evenly to get the coating.

The properties of the bio-latex prepared in Examples 1-4 are shown in Table 1. Among them, the average particle size of the latex was measured with a Dynapro dynamic light scattering instrument, the viscosity of the latex was measured with an NDJ-5S digital display rotary liquid viscometer, and the mechanical stability of the latex was measured with a GZ120 cantilever type powerful electric mixer.

Table 1 embodiment 1～4 makes the biological latex performance list

It can be seen from Table 1 that the particle size of the obtained bio-latex is relatively uniform by adding the long-chain PEG-modified starch with different molecular weights of carboxyl-terminated starches by means of extrusion. However, as the molecular weight of PEG increases, the latex viscosity increases, which is related to the increase in the chain length of PEG and the increase in viscosity. At the same time, the existence of long chains with high molecular weight, the steric hindrance is relatively large, and it is difficult to contact with starch molecules, which cannot well weaken the effect of hydrogen bonds in starch, and the particle size of latex increases accordingly. However, relatively uniform and stable nano-latex can be obtained through modification, and then added with pigments and additives to obtain bio-latex paint.

The above descriptions are only preferred implementation examples of the present invention, and are not intended to limit the technical solutions of the present invention in any form. All simple modifications, equivalent changes and modifications made to the above implementation examples according to the technical essence of the present invention fall within the protection scope of the present invention.

Claims (10)

1. a kind of biology latex, which is characterized in that prepare the component that raw material includes following parts by weight: 100 parts of starch, water 10~ 50 parts, 5~50 parts of glycerine, 1~20 part of sodium hydroxide, 1~30 part of methoxypolyethylene glycol-carboxylic acid.

2. biology latex according to claim 1, which is characterized in that the methoxypolyethylene glycol-carboxylic acid molecules amount It is 550~20000, the starch is cornstarch, in waxy corn starch, potato starch, wheaten starch, tapioca One or more.

3. the preparation method of biology latex of any of claims 1 or 2, which comprises the steps of: by starch and first Oxygroup-polyethylene glycol-carboxylic acid, sodium hydroxide, water, glycerine are uniformly mixed, and are placed into double screw extruder, reacted extrusion Biological latex is obtained, wherein the feeding section temperature of extruder is 30~100 DEG C, and screw speed is 40~500rpm, material heating Extruding zone temperature is 50~300 DEG C.

4. a kind of biology latex paint, which is characterized in that according to the mass fraction, including following components: it is as claimed in claim 1 or 2 10~30 parts of biological latex, 50~80 parts of pigment, 1~20 part of auxiliary agent.

5. biology latex paint according to claim 4, which is characterized in that the pigment is kaolin, calcium carbonate, carbon One or more of sour barium, talcum powder, aluminium hydroxide, zinc oxide, forging white powder.

6. biology latex paint according to claim 4, which is characterized in that the auxiliary agent is defoaming agent, lubricant, divides One or more of powder, thickener, water repellent agent.

7. biology latex paint according to claim 6, which is characterized in that the lubricant is odium stearate, tristearin One or more of sour potassium, ammonium stearate, paraffin, calcium oleate, polyethylene glycol, soybean lecithin, the dispersing agent For one or more of calgon, sodium pyrophosphate, sodium tetrapolyphosphate, sodium polymethacrylate, polyvinyl alcohol.

8. the preparation method of coating according to claim 6, which is characterized in that the thickener be methylcellulose, One or more of sodium carboxymethylcellulose, polyacrylic acid, the water repellent agent are melamine resin, carbonic acid One or more of zirconium ammonium, polyamide carbamide resin, the defoaming agent are dimethyl silicone polymer, octanol, phosphoric acid One or more of three propyl ester, tributyl phosphate.

9. the preparation method of the described in any item biological latex paints of claim 4~8, which comprises the following steps: According to the mass fraction, biological latex, pigment, auxiliary agent are uniformly mixed and obtain biogum cream coating.

10. application of the described in any item biological latex paints of claim 4~8 during the primary coat of paper industry, middle painting.