阅读说明：本技术 一种含有机硅长侧链的聚丙烯酸酯超疏水皮革光亮剂及其涂层的制备方法 (Polyacrylate super-hydrophobic leather brightener containing organic silicon long side chains and preparation method of coating thereof ) 是由 裴东杰 贾进营 郭国伟 于 2018-08-28 设计创作，主要内容包括：一种含有机硅长侧链的聚丙烯酸酯超疏水皮革光亮剂及其涂层的制备方法,包括以下工艺过程：1、等摩尔的甲基丙烯酸甲酯与羟基硅油,在催化剂作用下进行缩合反应,制备甲基丙烯酸硅氧烷；2、等摩尔的丙烯酸羟乙酯与甲基含氢硅油,在催化剂作用下进行脱氢反应,制备丙烯酸硅氧烷乙酯；3、将前面制备的甲基丙烯酸硅氧烷与丙烯酸硅氧烷乙酯作为单体,在引发剂的作用下,通过共聚反应制备含有机硅长侧链的聚丙烯酸酯；4、加入疏水纳米二氧化硅物理混合均匀即成超疏水皮革光亮剂；5、在超疏水皮革光亮剂中加入催化剂,直接在皮革表面喷涂或者涂刷并且发生固化反应,即可制备成具有荷叶效应的超疏水皮革涂层。本发明广泛应用于皮革、织物、纸张等纤维的表面处理与改性技术领域。(A preparation method of polyacrylate super-hydrophobic leather brightener containing organosilicon long side chains and a coating thereof comprises the following process steps: 1. carrying out condensation reaction on equal molar methyl methacrylate and hydroxyl silicone oil under the action of a catalyst to prepare methacrylic siloxane; 2. carrying out dehydrogenation reaction on hydroxyethyl acrylate and methyl hydrogen-containing silicone oil with equal mole under the action of a catalyst to prepare siloxane ethyl acrylate; 3. using the prepared methyl acrylic siloxane and acrylic siloxane ethyl ester as monomers, and preparing polyacrylate containing organosilicon long side chains through copolymerization reaction under the action of an initiator; 4. adding hydrophobic nano silicon dioxide, and physically and uniformly mixing to obtain the super-hydrophobic leather brightener; 5. adding a catalyst into the super-hydrophobic leather brightener, directly spraying or brushing the catalyst on the surface of the leather, and carrying out a curing reaction to prepare the super-hydrophobic leather coating with the lotus leaf effect. The invention is widely applied to the technical field of surface treatment and modification of fibers such as leather, fabrics, paper and the like.)

1. A polyacrylate super-hydrophobic leather brightener containing organic silicon long side chains and a preparation method of a coating thereof are characterized in that:

the preparation process comprises the following steps:

step one, carrying out condensation reaction on equal molar methyl methacrylate and hydroxyl silicone oil under the action of a catalyst to prepare methacrylic siloxane; wherein the mole number of the hydroxyl silicone oil is calculated by dividing the hydroxyl content by 17, and the condensation reaction temperature is 80-90 ℃;

step two, carrying out dehydrogenation reaction on hydroxyethyl acrylate and methyl hydrogen-containing silicone oil with equal mole under the action of a catalyst to prepare siloxane ethyl acrylate; wherein the mole number of the methyl hydrogen-containing silicone oil is calculated by dividing the hydrogen content by 1, and the dehydrogenation reaction temperature is 50-80 ℃;

step three, taking the methyl acrylic siloxane prepared in the step one and the acrylic siloxane ethyl ester prepared in the step two as monomers, and preparing polyacrylate containing organosilicon long side chains through copolymerization reaction under the action of an initiator; adding an organic solvent accounting for 60-80% of the total mass of the monomers and the solvent and an initiator solution of 1/2 into a multi-port reaction kettle with a stirring and reflux condenser, and heating to 90 ℃ by using a constant-temperature oil bath for later use;

step four, slowly dripping the initiator solution of 1/4 and the mixed monomer containing the methacrylic siloxane and the acrylic siloxane ethyl ester, wherein the mixed monomer accounts for 20-40% of the total mass of the monomers and the solvent, and the initiator solution is used for carrying out copolymerization reaction;

step five, the dripping time of all the raw materials is 1.0-3.0 h, and the reaction temperature of the materials is controlled to be 80-90 ℃;

step six, after all the raw materials are dripped, adding the residual 1/4 initiator solution into a reaction kettle, controlling the reaction temperature to be 80-90 ℃, and carrying out heat preservation reaction for 1.0-2.0 h;

seventhly, cooling to below 45 ℃, adjusting the pH =7-8, and adding hydrophobic nano-silica to physically and uniformly mix to obtain the super-hydrophobic leather brightener;

and step eight, adding a catalyst into the super-hydrophobic leather brightener, directly spraying or brushing the catalyst on the surface of the leather, and carrying out a curing reaction to prepare the super-hydrophobic leather coating with the lotus leaf effect.

2. The preparation method of the polyacrylate super-hydrophobic leather brightener containing the organosilicon long side chain and the coating thereof according to claim 1 is characterized in that: in the first step, the hydroxyl silicone oil is organic silicone oil containing hydroxyl at the terminal group, and the catalyst is dibutyltin dilaurate.

3. The preparation method of the polyacrylate super-hydrophobic leather brightener containing the organosilicon long side chain and the coating thereof according to claim 1 is characterized in that: in the second step, the methyl hydrogen-containing silicone oil is organic silicone oil with hydrogen-containing end groups and side chains, and the catalyst is inorganic strong base such as potassium hydroxide or sodium hydroxide.

4. The preparation method of the polyacrylate super-hydrophobic leather brightener containing the organosilicon long side chain and the coating thereof according to claim 1 is characterized in that: in the third step, the organic solvent is a mixture of octamethylcyclotetrasiloxane and methyl ethyl ketone; the initiator is azodiisobutyronitrile or benzoyl peroxide, and the solvent for dissolving the initiator is methyl ethyl ketone.

5. The preparation method of the polyacrylate super-hydrophobic leather brightener containing the organosilicon long side chain and the coating thereof according to claim 1 is characterized in that: in the fourth step, the mass ratio of the mixed monomer of the methacrylic siloxane and the acrylic siloxane ethyl ester = (2-8): (8-2).

6. The preparation method of the polyacrylate super-hydrophobic leather brightener containing the organosilicon long side chain and the coating thereof according to claim 1 is characterized in that: in step eight, the catalyst is dibutyltin dilaurate.

Technical Field

The invention belongs to the technical field of leather finishing materials, and particularly relates to a super-hydrophobic leather brightener prepared by a series of chemical reactions such as condensation, dehydrogenation, copolymerization, curing and the like and a preparation method of a coating thereof.

The invention can also be applied to the technical field of surface treatment and modification of fibers such as fabrics, paper and the like.

Background

The super-hydrophobic functional leather has high added value, can obviously improve the grade and market competitiveness of products, and becomes one of important directions for the development of leather industry. In actual leather finishing, the super-hydrophobic leather not only seeks excellent super-hydrophobic self-cleaning performance, but also has comprehensive functions of sanitary air permeability, wear resistance, durability, wearing comfort, weather resistance and the like. How to solve the problems of durability, wear resistance and the like of the super-hydrophobic leather, which puts higher requirements on leather materials serving for leather, is also a technical difficulty in the current preparation research of the super-hydrophobic leather. Therefore, the development, popularization and application of the new bionic super-hydrophobic leather material and the preparation process thereof have important practical significance.

At present, few reports on lotus leaf-like super-hydrophobic leather finishing agent and preparation and application research of the surface of the lotus leaf-like super-hydrophobic leather finishing agent are provided. Hydrophobic nano SiO for small group in Majian province₂The super-hydrophobic leather surface is constructed by spraying the coating on the leather surface, the static contact angle of water on the surface is as high as 170.3 degrees, but the coating influences the sanitary air permeability of the leather, and the coating is not wear-resistant and durable and also has serious extinction property. In patent CN201410366284.6, they also supported hydrophobic nano silica on the leather surface by layer-by-layer self-assembly technology to construct a super-hydrophobic coating, however, the reactivity of traditional nano silica is poor, especially the binding force with the functional group of leather fiber is poor, resulting in poor abrasion resistance of the coating. Maleic acid adopted by Shibi project group of Sichuan universityThe anhydride is copolymerized with natural animal and vegetable oil, and then reacts with dodecafluoroheptanol and octadecanol to prepare the fluorine-containing water-based copolymer emulsion for leather hydrophobic fatting agent, and researches show that: the treated leather surface has durable, soft and good super-hydrophobic performance, and the maximum contact angle of water reaches 155 degrees. In addition, the method utilizes a low-temperature plasma technology to polymerize and deposit octamethylcyclotetrasiloxane (D4) on the surface of the buffed leather to prepare the super-hydrophobic buffed leather, and the maximum static contact angle of water on the surface reaches 155 degrees, and the rolling angle of the surface is lower than 10 degrees. However, the organic fluorine material is expensive and has destructive effect on the atmospheric ozone layer, and the D4 polymer has poor film-forming property and small bonding force on leather, namely has no durability; the plasma technology needs special equipment and instruments, and has the defects of high cost and difficulty in large-area film preparation. The existing super-hydrophobic material and leather super-hydrophobic surface preparation technology are difficult to realize commercial application.

Disclosure of Invention

The invention aims to disclose a polyacrylate super-hydrophobic leather brightener containing organosilicon long side chains and a preparation method of a coating thereof, and a super-hydrophobic coating with sanitation, air permeability, wear resistance and durability can be obtained on the surface of leather by a simple spraying or brushing method.

In order to achieve the purpose, the technical scheme of the invention is realized as follows: a preparation method of polyacrylate super-hydrophobic leather brightener containing organosilicon long side chains and a coating thereof comprises the following steps:

step one, carrying out condensation reaction on equal molar methyl methacrylate and hydroxyl silicone oil under the action of a catalyst to prepare methacrylic siloxane; wherein the mole number of the hydroxyl silicone oil is calculated by dividing the hydroxyl content by 17, and the condensation reaction temperature is 80-90 ℃;

step two, carrying out dehydrogenation reaction on hydroxyethyl acrylate and methyl hydrogen-containing silicone oil with equal mole under the action of a catalyst to prepare siloxane ethyl acrylate; wherein the mole number of the methyl hydrogen-containing silicone oil is calculated by dividing the hydrogen content by 1, and the dehydrogenation reaction temperature is 50-80 ℃;

step three, taking the methyl acrylic siloxane prepared in the step one and the acrylic siloxane ethyl ester prepared in the step two as monomers, and preparing polyacrylate containing organosilicon long side chains through copolymerization reaction under the action of an initiator; adding an organic solvent accounting for 60-80% of the total mass of the monomers and the solvent and an initiator solution of 1/2 into a multi-port reaction kettle with a stirring and reflux condenser, and heating to 90 ℃ by using a constant-temperature oil bath for later use;

step four, slowly dripping the initiator solution of 1/4 and the mixed monomer containing the methacrylic siloxane and the acrylic siloxane ethyl ester, wherein the mixed monomer accounts for 20-40% of the total mass of the monomers and the solvent, and the initiator solution is used for carrying out copolymerization reaction;

step five, the dripping time of all the raw materials is 1.0-3.0 h, and the reaction temperature of the materials is controlled to be 80-90 ℃;

step six, after all the raw materials are dripped, adding the residual 1/4 initiator solution into a reaction kettle, controlling the reaction temperature to be 80-90 ℃, and carrying out heat preservation reaction for 1.0-2.0 h;

seventhly, cooling to below 45 ℃, adjusting the pH =7-8, and adding hydrophobic nano-silica to physically and uniformly mix to obtain the super-hydrophobic leather brightener;

and step eight, adding a catalyst into the super-hydrophobic leather brightener, directly spraying or brushing the catalyst on the surface of the leather, and carrying out a curing reaction to prepare the super-hydrophobic leather coating with the lotus leaf effect.

In the first step, the hydroxyl silicone oil is organic silicone oil containing hydroxyl at the terminal group, and the catalyst is dibutyltin dilaurate.

In the second step, the methyl hydrogen-containing silicone oil is organic silicone oil with hydrogen-containing end groups and side chains, and the catalyst is inorganic strong base such as potassium hydroxide or sodium hydroxide.

In the third step, the organic solvent is a mixture of octamethylcyclotetrasiloxane and methyl ethyl ketone; the initiator is azodiisobutyronitrile or benzoyl peroxide, and the solvent for dissolving the initiator is methyl ethyl ketone.

In the fourth step, the mass ratio of the mixed monomers of the methacrylic siloxane and the acrylic siloxane ethyl ester = (2-8): (8-2).

In step eight, the catalyst is dibutyltin dilaurate.

Compared with the prior art, the invention has the beneficial effects that: 1. expensive perfluoroacrylate raw materials are not used as polymerization monomers, cheap organic silicone oil is used as a low-surface-energy substance, and a leather coating with good hydrophobic effect is obtained; 2. the prepared super-hydrophobic leather brightener solution has good uniformity and stability and can be stored for a long time without layering by adopting an octamethylcyclotetrasiloxane nonpolar solvent with good solubility with organic silicon oil and a methyl ethyl ketone polar solvent with good solubility with acrylic ester as composite solvents; 3. hydroxyl silicone oil and methyl hydrogen-containing silicone oil which are not completely reacted are solidified into a film under the catalysis of dibutyltin dilaurate, so that the surface of the leather is easier to dry and is not greasy any more; 4. the invention has the advantages of easily obtained raw materials, simple and feasible preparation process and mass preparation.

Drawings

FIG. 1 is a process flow diagram of the present invention.

FIG. 2 shows the main chemical reaction formula of the present invention.

Detailed Description

The invention is described in further detail below with reference to specific embodiments and the attached drawings, but the scope of the invention is not limited to the following.

As shown in figures 1 and 2, a preparation method of a polyacrylate super-hydrophobic leather brightener containing organosilicon long side chains and a coating thereof comprises the following steps:

step one, carrying out condensation reaction on equal molar methyl methacrylate and hydroxyl silicone oil under the action of a catalyst to prepare methacrylic siloxane; wherein the mole number of the hydroxyl silicone oil is calculated by dividing the hydroxyl content by 17, and the condensation reaction temperature is 80-90 ℃;

step two, carrying out dehydrogenation reaction on hydroxyethyl acrylate and methyl hydrogen-containing silicone oil with equal mole under the action of a catalyst to prepare siloxane ethyl acrylate; wherein the mole number of the methyl hydrogen-containing silicone oil is calculated by dividing the hydrogen content by 1, and the dehydrogenation reaction temperature is 50-80 ℃;

step three, taking the methyl acrylic siloxane prepared in the step one and the acrylic siloxane ethyl ester prepared in the step two as monomers, and preparing polyacrylate containing organosilicon long side chains through copolymerization reaction under the action of an initiator; adding an organic solvent accounting for 60-80% of the total mass of the monomers and the solvent and an initiator solution of 1/2 into a multi-port reaction kettle with a stirring and reflux condenser, and heating to 90 ℃ by using a constant-temperature oil bath for later use;

step four, slowly dripping the initiator solution of 1/4 and the mixed monomer containing the methacrylic siloxane and the acrylic siloxane ethyl ester, wherein the mixed monomer accounts for 20-40% of the total mass of the monomers and the solvent, and the initiator solution is used for carrying out copolymerization reaction;

step five, the dripping time of all the raw materials is 1.0-3.0 h, and the reaction temperature of the materials is controlled to be 80-90 ℃;

step six, after all the raw materials are dripped, adding the residual 1/4 initiator solution into a reaction kettle, controlling the reaction temperature to be 80-90 ℃, and carrying out heat preservation reaction for 1.0-2.0 h;

seventhly, cooling to below 45 ℃, adjusting the pH =7-8, and adding hydrophobic nano-silica to physically and uniformly mix to obtain the super-hydrophobic leather brightener;

and step eight, adding a catalyst into the super-hydrophobic leather brightener, directly spraying or brushing the catalyst on the surface of the leather, and carrying out a curing reaction to prepare the super-hydrophobic leather coating with the lotus leaf effect.

In the first step, hydroxyl silicone oil is organic silicone oil containing hydroxyl at a terminal group, and a catalyst is dibutyltin dilaurate; in the second step, the methyl hydrogen-containing silicone oil is organic silicone oil with hydrogen contained in both end group and side chain, and the catalyst is inorganic strong base such as potassium hydroxide or sodium hydroxide; in the third step, the organic solvent is a mixture of octamethylcyclotetrasiloxane and methyl ethyl ketone; the initiator is azodiisobutyronitrile or benzoyl peroxide, and the solvent for dissolving the initiator is methyl ethyl ketone; in the fourth step, the mass ratio of the mixed monomers of the methacrylic siloxane and the acrylic siloxane ethyl ester = (2-8): (8-2); in step eight, the catalyst is dibutyltin dilaurate.

Several embodiments of the present invention are described in detail below.