CN112574367A - Multifunctional coating lubricant, and preparation method and application thereof - Google Patents

Abstract

The invention discloses a multifunctional paint lubricant, a preparation method and application thereof, wherein the multifunctional paint lubricant comprises the following raw materials in parts by weight: 100 parts of oxidized polyethylene wax, 5-30 parts of active monomer, 0.1-2 parts of initiator, 2-20 parts of alkali, 0-15 parts of composite emulsifier and 150 parts of water, wherein the active monomer comprises a first monomer and a second monomer, the first monomer is at least one of polyethylene glycol methacrylate, polyethylene glycol itaconate and polyethylene glycol acrylate, and the second monomer is at least one of itaconic acid, citraconic acid, acrylic acid, methacrylic acid, maleic anhydride, acrylamide and styrene. Also disclosed are methods for making the multifunctional coating lubricant and its use in papermaking. By grafting functional monomers such as polyethylene glycol methacrylate, polyethylene glycol itaconate, polyethylene glycol acrylate and the like, polyether side chains are introduced, the water solubility is increased, the emulsion is easier to emulsify, few or no emulsifier is used, the emulsion with high stability can be prepared, and the particle size of the prepared finished product is small and is about 50-500 nm.

Description

Multifunctional coating lubricant, and preparation method and application thereof

Technical Field

The invention relates to the field of papermaking, in particular to a multifunctional coating lubricant for papermaking industry and a preparation method and application thereof.

Background

Paper making, an ancient technology, has a long history in China, and since the east Han Chuan Lun improved paper making technology, paper is widely used, and is known as four major inventions in China. The development of the technology has been advanced to the present, the demand of paper is increasing, and the demand of paper is also increasing, and therefore, many special chemicals including various types of paper making coating lubricants, such as calcium stearate and oxidized polyethylene wax series products, are developed.

However, the oxidized polyethylene wax products on the market lack good wettability, so that the smoothness and the glossiness of the paper are not enough, and the requirements of people on the paper cannot be met. The anionic or nonionic modified oxidized polyethylene wax emulsion described in domestic literature and patents is obtained by improving water solubility for polymerization of oxidized polyethylene wax and acrylic monomers, and then saponifying and emulsifying. The Caochlore patent 'a preparation method of self-emulsifying wax' is that wax and acrylic acid monomer are polymerized, and then the self-emulsifying wax is obtained through saponification and vacuum dehydration, and the solid form is convenient for transportation, and when the self-emulsifying wax is used, the wax is directly melted and then heated and stirred without adding an emulsifier. However, the obtained emulsion has large particle size of 500-4000nm and poor stability, and the large particle size generally causes streaks on the surface of paper.

Therefore, the present inventors, aiming at the above technical problems, aim to invent a multifunctional lubricant, and a preparation method and application thereof.

Disclosure of Invention

In order to overcome the defects, the invention aims to provide a multifunctional paint lubricant and a preparation method and application thereof.

In order to achieve the above purposes, the invention adopts the technical scheme that: the multifunctional paint lubricant comprises the following raw materials in parts by weight: 100 parts of oxidized polyethylene wax, 5-30 parts of active monomer, 0.1-2 parts of initiator, 2-20 parts of alkali, 0-15 parts of composite emulsifier and 400 parts of water, wherein the active monomer comprises a first monomer and a second monomer, the first monomer is at least one of polyethylene glycol methacrylate, polyethylene glycol itaconate and polyethylene glycol acrylate, and the second monomer is at least one of itaconic acid, citraconic acid, acrylic acid, methacrylic acid, maleic anhydride, acrylamide and styrene.

Preferably, the average molecular weight of the first monomer is 200-3000 g/mol.

Preferably, the acid value of the oxidized polyethylene wax is 10-40mg KOH/g, and the molecular weight is 1000-4000 g/mol.

Preferably, the initiator is dibenzoyl peroxide. Dibenzoyl peroxide, also known as benzoyl peroxide, is commonly known as initiator BPO, a commonly used initiator.

Preferably, the base is at least one of an inorganic base and an organic base. The inorganic base is generally sodium hydroxide, potassium hydroxide, etc., and the organic base is generally diethylenetriamine, triethylenetetramine, tetraethylenepentamine, hydroxyethylethylenediamine, ethylenediamine, ethanolamine, diethanolamine, triethanolamine, methylethanolamine, dimethylethanolamine, etc., and when used, one kind may be selected, or two kinds may be mixed.

Preferably, the complex emulsifier is at least one of a nonionic surfactant and an anionic surfactant. The nonionic surfactant includes isotridecanol polyoxyethylene ether, AEO series, SPAN, TWEEN, fatty amine polyoxyethylene ether, etc., and the anionic surfactant is generally K12.

A preparation method of a multifunctional paint lubricant comprises the following steps:

firstly, graft polymerization, introducing nitrogen into a reaction kettle, then adding oxidized polyethylene wax, a first monomer and a solid second monomer, simultaneously uniformly mixing a liquid second monomer and an initiator, then adding the mixture into a dropwise adding tank, starting a stirrer in the reaction kettle, simultaneously heating the oxidized polyethylene wax to a molten state, starting the dropwise adding tank to dropwise add the liquid second monomer and the initiator into the reaction kettle, and preserving heat at the temperature of 100 ℃ and 130 ℃ after dropwise adding;

secondly, neutralizing and emulsifying, namely mixing alkali and water according to the proportion, or mixing alkali, water and a composite emulsifier, uniformly stirring, heating to 80-100 ℃, adding the heat-preserved substances in the first step into the alkali water mixed solution under the stirring condition of 500 plus materials at 1000rpm, and uniformly stirring;

thirdly, discharging, and cooling the substances in the second step to 45 ℃ to obtain the multifunctional lubricant.

In general operation, nitrogen is introduced into a reaction kettle with a stirrer, a dropping tank, a condenser, a thermometer and a nitrogen interface for nitrogen protection, oxidized polyethylene wax, a first monomer and a solid second monomer are added, and simultaneously, a liquid second monomer and an initiator are uniformly mixed and added into the dropping tank for later use. Heating oxidized polyethylene wax to 90-130 ℃ for melting under the stirring condition, dropwise adding into a dropwise adding tank for 1-4h, and then preserving heat at 100-130 ℃ for 1-4 h. Preparing mixed solution of alkali and water, or mixed solution of alkali, water and composite emulsifier, stirring, and keeping the temperature at 80-100 deg.C for use. And (3) under stirring at 1000rpm for 500-. And obtaining the coating lubricant. Cooling to below 45 deg.C, and discharging.

Since the dropping tank is used for dropping, when more than two kinds of second monomers are selected, the solid second monomers in different solid-liquid states need to be added respectively, namely the solid second monomers are placed in the reaction kettle, and the liquid second monomers are placed in the dropping tank.

The invention also discloses the application of the multifunctional coating lubricant in papermaking.

Compared with the similar products, the multifunctional paint lubricant has the advantages that the product prepared by the invention introduces polyether side chains by grafting functional monomers containing methacrylic acid polyethylene glycol ester, polyethylene glycol itaconate, polyethylene glycol acrylate and the like, increases water solubility, is easier to emulsify, and can prepare emulsion with high stability by using little or no emulsifier. Meanwhile, the prepared finished product has small grain diameter of about 50-500 nm. Meanwhile, the dispersibility of the oil-based oil-. Meanwhile, the particle size is small, the specific surface area is large, paper scratches caused by overlarge particle size in the coating can be avoided, and a better effect can be exerted.

The preparation method of the multifunctional coating lubricant has the beneficial effects that the commercially available oxidized polyethylene wax and the active monomer are subjected to graft polymerization under the action of the initiator, so that the hydrophilic structure is increased; then adding the mixture into a mixed solution of alkali and water or a mixed solution of alkali, water and a compound emulsifier, and preparing a finished product by one step. The emulsifying dispersivity, the stability and the wettability are improved, and the high-efficiency and high-stability coating lubricant is obtained.

The multifunctional coating lubricant has the beneficial effects that the multifunctional coating lubricant has excellent external lubricity and strong internal dispersion lubrication effect, so that the smoothness, the glossiness and the like of paper are improved.

Detailed Description

The following detailed description of the preferred embodiments of the present invention is provided to enable those skilled in the art to more readily understand the advantages and features of the present invention, and to clearly and unequivocally define the scope of the present invention.

Example 1

Introducing nitrogen into a 250ml flask with a stirrer, a dropping tank, a condenser, a thermometer and a nitrogen interface, and adding 100g of oxidized polyethylene wax, 20g of polyethylene glycol itaconate, 2.5g of citraconic acid and 2.5g of maleic anhydride for later use. BPO 0.6g was charged. Stirring and heating to 120 ℃ for melting, and keeping the temperature for 4 h.

And (3) preparing an alkaline water mixed solution, mixing 189g of water and 3g of sodium hydroxide, uniformly stirring, heating to 90 ℃, and keeping the temperature for later use. And (3) under stirring at 1000rpm for 500-. Cooling to below 45 deg.C, and discharging. The coating lubricant is obtained, and is a light yellow semitransparent liquid with the content of about 40 percent and the particle size of about 200-400 nm.

Example 2

Introducing nitrogen into a 250ml flask with a stirrer, a dropping tank, a condenser, a thermometer and a nitrogen interface, and adding 100g of oxidized polyethylene wax, 30g of water and 5g of itaconic acid for later use. 15g of polyethylene glycol methacrylate, 5g of acrylic acid, 2.5g of styrene and 0.5g of BPO are uniformly mixed and added into a dropwise adding tank for later use. Heating the oxidized polyethylene wax material to 110 ℃ for melting under stirring, dropwise adding the monomer, finishing dropwise adding for 2h, and then preserving heat at 110 ℃ for 2 h.

Preparing alkaline water mixed solution, mixing 210g of water and 13g of diethanolamine, uniformly stirring, heating to 85 ℃, and keeping the temperature for later use. And (3) under stirring at 1000rpm for 500-. Cooling to below 45 deg.C, and discharging. The coating lubricant is obtained, and is a light yellow semitransparent liquid with the content of about 35 percent and the particle size of about 200-400 nm.

Example 3

A250 ml flask equipped with a stirrer, a dropping tank, a condenser, a thermometer, and a nitrogen port was purged with nitrogen, and 100g of oxidized polyethylene wax and 2.5g of citraconic acid were added thereto for further use. 2.5g of methacrylic acid, 5g of styrene, 13g of polyethylene glycol acrylate and 1.2g of BPO are uniformly mixed and added into a dropwise adding tank for later use. Heating the oxidized polyethylene wax material to 110 ℃ for melting under stirring, dropwise adding the monomer, finishing dropwise adding for 2h, and then preserving heat at 110 ℃ for 2 h.

Preparing an emulsifier liquid, mixing and stirring uniformly 198g of water, 4g and 2g of isomeric tridecanol polyoxyethylene ether, 4g and 2g of AEO-9 and 8g of triethanolamine, and heating to 95 ℃ for heat preservation for later use. And (3) under stirring at 1000rpm for 500-. Cooling to below 45 deg.C, and discharging. The coating lubricant is obtained, and is a light yellow semitransparent liquid with the content of about 40 percent and the particle size of about 100-200 nm.

Example 4

Introducing nitrogen into a 250ml flask with a stirrer, a dropping tank, a condenser, a thermometer and a nitrogen interface, and adding 100g of oxidized polyethylene wax, 30g of water, 2.5g of itaconic acid and 12.5g of polyethylene glycol itaconate for later use. 10g of acrylic acid and 1.0g of BPO are uniformly mixed and added into a dropwise adding tank for later use. Heating the oxidized polyethylene wax material to 100 ℃ for melting, dropwise adding the monomer, completing dropwise adding for 1.5h, and then preserving the temperature for 2h at 110 ℃.

Preparing emulsifier liquid, uniformly stirring 301g of water, 2g and 5g of isomeric tridecanol polyoxyethylene ether and fatty amine polyoxyethylene ether respectively and 17g of dimethylethanolamine, and heating to 90 ℃ for heat preservation for later use. And (3) under stirring at 1000rpm for 500-. Cooling to below 45 deg.C, and discharging. The coating lubricant is obtained as a yellowish translucent liquid with a content of about 30% and a particle size of about 50-150 nm.

The finished products prepared in examples 1-4 were tested. The properties of the resulting coated papers were measured by coating with the same coating formulation as a commercial control. The coating formulation is shown in table 1 and the coated paper properties are shown in table 2.

TABLE 1 coating formulations

GCC is ground calcium carbonate. Coating the coating on the copper plate base paper by using a No. 1 coating rod, wherein the coating weight is 15g/m²And then standby.

Calendering conditions are as follows: the coated paper samples were each calendered twice (4.5MPa,80 ℃) using a small calender. And (5) standby. And (5) adopting a national standard method to carry out performance test on the paper.

And (3) judging standard: the larger the smoothness and gloss, the better the effect.

TABLE 2 paper surface Properties

	Blank space	Comparative example	Example 1	Example 2	Example 3	Example 4
							Smoothness s	80	90	104	102	99	101
Coating gloss%	55	63	68	71	69	70
							Print gloss%	80	84	87	89	87	88

From the above application results, it can be seen that: compared with a comparative example, the coating lubricant prepared by the coating lubricants of the embodiments 1 to 4 of the invention is applied to a coating formula, and can obviously improve the smoothness and the glossiness of coated paper.

In conclusion, compared with the coating lubricant prepared by the prior art, the coating lubricant prepared by the invention has the following characteristics and advantages: by grafting functional monomers such as polyethylene glycol methacrylate, polyethylene glycol itaconate, polyethylene glycol acrylate and the like, polyether side chains are introduced, so that the emulsion is easy to emulsify due to increased water solubility, and the emulsion with high stability can be prepared by using little or no emulsifier. Meanwhile, the prepared finished product has small grain diameter of about 50-500 nm. Meanwhile, the dispersibility of the oil-based oil-. Meanwhile, the particle size is small, the specific surface area is large, paper scratches caused by overlarge particle size in the coating can be avoided, and a better effect can be exerted.

The above embodiments are merely illustrative of the technical concept and features of the present invention, and the present invention is not limited thereto, and any equivalent changes or modifications made according to the spirit of the present invention should be included in the scope of the present invention.

Claims (8)

1. A multifunctional paint lubricant is characterized in that: the material comprises the following components by weight: 100 parts of oxidized polyethylene wax, 5-30 parts of active monomer, 0.1-2 parts of initiator, 2-20 parts of alkali, 0-15 parts of composite emulsifier and 400 parts of water, wherein the active monomer comprises a first monomer and a second monomer, the first monomer is at least one of polyethylene glycol methacrylate, polyethylene glycol itaconate and polyethylene glycol acrylate, and the second monomer is at least one of itaconic acid, citraconic acid, acrylic acid, methacrylic acid, maleic anhydride, acrylamide and styrene.

2. The multifunctional paint lubricant of claim 1, wherein: the average molecular weight of the first monomer is 200-3000 g/mol.

3. The multifunctional paint lubricant of claim 1, wherein: the acid value of the oxidized polyethylene wax is 10-40mg KOH/g, and the molecular weight is 1000-4000 g/mol.

4. The multifunctional paint lubricant of claim 1, wherein: the initiator is dibenzoyl peroxide.

5. The multifunctional paint lubricant of claim 1, wherein: the alkali is at least one of inorganic alkali and organic alkali.

6. The multifunctional paint lubricant of claim 1, wherein: the compound emulsifier is at least one of nonionic surfactant and anionic surfactant.

7. The method of preparing the multifunctional paint lubricant of any one of claims 1 to 6, characterized by comprising the steps of:

firstly, graft polymerization, introducing nitrogen into a reaction kettle, then adding oxidized polyethylene wax, a first monomer and a solid second monomer, simultaneously uniformly mixing a liquid second monomer and an initiator, then adding the mixture into a dropwise adding tank, starting a stirrer in the reaction kettle, simultaneously heating the oxidized polyethylene wax to a molten state, starting the dropwise adding tank to dropwise add the liquid second monomer and the initiator into the reaction kettle, and preserving heat at the temperature of 100 ℃ and 130 ℃ after dropwise adding;

secondly, neutralizing and emulsifying, namely mixing alkali and water according to the proportion, or mixing alkali, water and a composite emulsifier, uniformly stirring, heating to 80-100 ℃, adding the heat-preserved substances in the first step into the alkali water mixed solution under the stirring condition of 500 plus materials at 1000rpm, and uniformly stirring;

thirdly, discharging, and cooling the substances in the second step to 45 ℃ to obtain the multifunctional lubricant.

8. Use of the multifunctional coating lubricant according to any one of claims 1 to 7 in papermaking.