CN109385181B

CN109385181B - Preparation method of epoxy eucommia rubber-containing paint

Info

Publication number: CN109385181B
Application number: CN201811208336.1A
Authority: CN
Inventors: 方庆红; 冯潇
Original assignee: Shenyang University of Chemical Technology
Current assignee: Shenyang University of Chemical Technology
Priority date: 2018-10-17
Filing date: 2018-10-17
Publication date: 2021-01-01
Anticipated expiration: 2038-10-17
Also published as: CN109385181A

Abstract

A preparation method of an epoxy eucommia rubber coating relates to a preparation method of a rubber coating, and comprises the steps of firstly purifying eucommia rubber twice, and then carrying out epoxy modification on the eucommia rubber by adopting an emulsion method to obtain the epoxy eucommia rubber. Dissolving the prepared epoxidized eucommia ulmoides rubber in a certain amount of solvent, and heating and stirring in a water bath kettle; after the gutta percha is completely dissolved, a certain amount of resin and a solvent are mixed according to a certain mass ratio, a certain amount of curing agent and defoaming agent are added into the mixed substance after a period of time, and the mixture is stirred uniformly after ultrasonic oscillation, so that a coating can be coated and the performance of the coating can be detected. The coating is carried out by changing the epoxy degree of the gutta percha and the proportion of the matrix, and the performance of the coating is tested. The paint prepared by the invention has the advantages of uniform dispersion, excellent appearance and good performance. The corrosion resistance and the adhesive force of the coating are effectively improved.

Description

Preparation method of epoxy eucommia rubber-containing paint

Technical Field

The invention relates to a preparation method of a rubber coating, in particular to a preparation method of a rubber coating containing epoxidized eucommia ulmoides.

Background

The performance of the coating determines the protective effect of the coating, and the protective coating used in the field of marine heavy corrosion resistance has the following advantages: the mechanical property is good, and the rain and seawater scouring collision and even friction are resisted; good stability, acid and alkali resistance, chemical resistance, oil resistance, aging resistance and ultraviolet resistance; the adhesive force is strong, and the adhesive force and the adhesive property with the substrate are strong; easy construction and environmental protection. However, these problems still exist as far as the present situation is concerned: the adhesive force with the substrate is not high, and the adhesive force needs to be mixed with other resin (such as epoxy resin) or modified to improve the adhesive force; because the epoxy resin is difficult to dissolve in the aqueous solution, the used organic solvent has high price and is easy to volatilize, some epoxy resins have toxicity and high VOC (volatile organic compound content), do not meet the requirement of the current environmental protection, have low solubility and large required solvent amount, and are very easy to cause pollution and waste. The performances of the paint are not independent and are mutually influenced and closely related, and the development of an anticorrosive coating with the advantages is one of the most important works at present.

The current rubber coating takes natural rubber derivatives or synthetic rubber as main film forming substances. The main applications in a wider range are chlorosulfonated polyethylene anticorrosive coatings and chlorinated rubber anticorrosive coatings. Some researchers improve some defects of the traditional rubber anticorrosive paint by modifying or mixing with other paints. Bulgakov and the like modify chlorosulfonated polyethylene rubber with amino compounds to enhance the bonding strength by 2-5 times. The glass flakes are treated by a compound silane treating agent, and then the high-performance modified epoxy resin coating is prepared according to the using amount of 20-30%. The flaky glass flakes in the coating effectively prevent corrosive media from invading and have good corrosion prevention effect on the steel structure of ocean engineering. The measurement results show that the adhesive force, the aging resistance and the like of the coating are greatly enhanced. However, although these modification methods improve the coating properties, carbon tetrachloride is still used as a solvent, which is itself toxic and causes damage to the ozone layer, so that its application is limited, and the development of low VOC rubber coatings is the direction of development. The development of new solvents for replacing carbon tetrachloride to produce rubber is still a research and development hotspot and difficulty in the rubber coating industry, and the development of new solvents for replacing carbon tetrachloride to produce chlorinated rubber is still a research and development hotspot and difficulty in the rubber coating industry.

Gutta-percha (EUG) as a natural polymer material has a chemical formula of trans-polyisoprene. The gutta-percha is a thermoelastic rubber body with excellent fatigue resistance, comprehensive mechanical property and processing property. Epoxidation of unsaturated rubbers is an important direction for rubber modification. The polar epoxy group is introduced into the polymer chain, so that the original performance of the polymer chain can be maintained, and a plurality of new excellent performances can be brought by the introduction of new groups. In addition, the epoxy group is a reactive group, and the epoxidized rubber can be subjected to reactive blending modification with a polar polymer containing carboxyl, amino, anhydride and other groups, so that the application field of the rubber material can be further widened.

The eucommia ulmoides gum as a unique gum seed in China has certain advantages in research and development. The gutta-percha is acid-resistant, alkali-resistant, water-resistant, corrosion-resistant, good in aging resistance, good in wear resistance and fatigue resistance; the film has good film forming property, and the obtained film has high strength, good adhesion, low dielectric loss and low air permeability; secondly, the solvent of the eucommia ulmoides rubber coating belongs to a low-toxicity solvent, so that the eucommia ulmoides rubber coating has no irritation to skin, and the using effect of the coating is greatly improved; disadvantages are the low adhesion strength and the poor resistance to ageing, and the need to mix or modify with other resins (such as epoxy resins) to improve adhesion. The development fields of the coatings comprise anticorrosion coatings, electromagnetic shielding coatings, conductive coatings and the like, and the preparation of the gutta percha coatings can completely meet the development and application of the coatings.

Disclosure of Invention

The invention aims to provide a preparation method of an epoxy eucommia rubber-containing paint, wherein epoxy eucommia rubber and resin are used as film-forming substances to prepare the eucommia rubber anticorrosive paint, the epoxy eucommia rubber anticorrosive paint plays a very large role in delaying metal corrosion, enhances the adhesion of a coating and a substrate, and greatly reduces toxicity and pollution and waste compared with other toxic solvents.

The purpose of the invention is realized by the following technical scheme:

the epoxy degree of the gutta-percha is firstly tested, then the dosage of the resin is ensured to be unchanged, and the dosage of the epoxy gutta-percha is changed to prepare the coating. For the coating, the corrosion resistance is obviously improved, and the adhesion force is firstly increased and then reduced, so that a highest point is reached to prove the performance of the coating.

The invention relates to a preparation method of an epoxidized eucommia rubber coating, which comprises the following steps: firstly, purifying gutta-percha twice, secondly, performing gutta-percha epoxidation, testing the epoxy degree of the gutta-percha, dissolving the prepared epoxidized gutta-percha in a certain amount of solvent, heating and stirring, dissolving resin in a certain amount of solvent, heating and stirring, finally, adding a curing agent and a defoaming agent, stirring uniformly after ultrasonic oscillation, and coating and detecting the performance of the coating. In which a coating test was performed by changing the amount of epoxidized eucommia ulmoides rubber while maintaining a fixed amount of resin.

The specific scheme of the invention is as follows:

a preparation method of an epoxy eucommia ulmoides rubber-containing paint comprises the following preparation steps:

firstly, purifying gutta-percha twice, then carrying out gutta-percha epoxidation, testing the epoxy degree of the gutta-percha, then dissolving the prepared epoxidized gutta-percha in a certain amount of solvent, heating and stirring; dissolving the resin in a certain amount of solvent, heating and stirring, finally adding the curing agent and the defoaming agent, and stirring uniformly after ultrasonic oscillation so as to coat. The coating is carried out by changing the epoxy degree of the gutta percha and the proportion of the matrix. The resin is kept in a fixed amount in the matrix proportion, and the coating test is carried out by changing the using amount of the epoxidized eucommia rubber.

The epoxy degree of the epoxy eucommia rubber coating is 18-40%.

According to the preparation method of the epoxy eucommia rubber-containing coating, the resin is one of alkyd resin, polyamide resin, acrylic resin and epoxy resin.

The preparation method of the epoxidized eucommia ulmoides rubber-containing coating is characterized in that the reaction temperature is 45-75 ℃.

The preparation method of the epoxidized eucommia rubber-containing coating has the reaction time of 1.5-3 h.

According to the preparation method of the epoxidized eucommia ulmoides rubber coating, the used solvent is one of chloroform, ethyl acetate, toluene and petroleum ether; the dosage of the epoxy resin is 10-20 times of that of the epoxy gutta-percha and 3-5 times of that of the resin.

According to the preparation method of the epoxy eucommia ulmoides rubber coating, the amount of the curing agent is 0.5-0.6 time of that of the matrix, and the amount of the defoaming agent is 1/100 of the matrix.

According to the preparation method of the epoxy eucommia ulmoides rubber-containing paint, the ratio of epoxy eucommia ulmoides rubber to epoxy resin is (0.25): 1-3: 1.

The preparation method of the epoxidized eucommia rubber coating has the ultrasonic time of 10-60 min.

The invention has the advantages and effects that:

the gutta-percha of the invention is used as a peculiar rubber variety in China, and is used as a film forming substance to prepare the coating, so that the shortage of natural rubber resources in China can be relieved, and the resources can be fully utilized. The gutta-percha has good acid resistance, alkali resistance, water resistance and corrosion resistance. For the research of the anticorrosive paint, the addition of the gutta percha can improve the corrosion resistance effect of the anticorrosive paint. Can meet the requirement of high corrosion resistance.

Drawings

FIG. 1 is an electrochemical analysis chart of epoxy eucommia rubber with different epoxy degrees;

FIG. 2 is a graph showing the adhesion of epoxy gutta-percha with different epoxy degrees.

Detailed Description

The present invention will be described in detail with reference to examples.

According to the invention, firstly, the eucommia rubber is purified twice, then the eucommia rubber is subjected to epoxidation modification by adopting an emulsion method to prepare the epoxidized eucommia rubber, and the epoxy degree of the epoxidized eucommia rubber is tested. Dissolving the prepared epoxidized eucommia ulmoides rubber in a certain amount of solvent, heating and stirring, mixing a certain amount of resin and the solvent according to a certain mass ratio after the eucommia ulmoides rubber is completely dissolved, pouring the mixture, adding a certain amount of curing agent and defoaming agent into the mixture after a period of time, and uniformly stirring after ultrasonic oscillation to coat and detect the performance of the coating. In which a coating test was performed by changing the amount of epoxidized eucommia ulmoides rubber while maintaining a fixed amount of resin.

The preparation route of the epoxidized eucommia ulmoides rubber is as follows:

example 1

Adding 5g EUG and 70ml petroleum ether into a 250ml container with a stirrer, a thermometer and a constant pressure funnel, heating to 50 ℃, starting stirring, after the EUG is completely dissolved, dropwise adding 40ml distilled water at a fixed speed for 30min, stirring for 2h, then adding 2.5ml formic acid, dropwise adding 15ml hydrogen peroxide at a speed of 1ml/min, stirring for 2h at 50 ℃, and washing EEUG to be neutral by using alcohol. The mixture was dried in a vacuum oven at room temperature to constant weight, and the degree of epoxy was measured to be 21.1% after drying.

Dissolving 1g of epoxidized eucommia ulmoides rubber in 20ml of ethyl acetate, heating and stirring in a water bath kettle, then dissolving 2g of epoxy resin in 5ml of ethyl acetate, heating and stirring in the water bath kettle, finally adding 1.5g of curing agent and 0.03g of defoaming agent, uniformly stirring, and coating and curing and detecting the performance of the coating.

Example 2

Adding 10g EUG and 140ml petroleum ether into a 500ml container with a stirrer, a thermometer and a constant pressure funnel, heating to 55 ℃, starting stirring, after the EUG is completely dissolved, dropwise adding 80ml distilled water at a fixed speed for 30min, stirring for 2h, then adding 5ml formic acid, dropwise adding 30ml hydrogen peroxide at a speed of 1ml/min, stirring for 2h at 55 ℃, and washing EEUG to be neutral by using alcohol. The mixture was dried in a vacuum oven at room temperature to constant weight, and the degree of epoxy was found to be 35.8% after drying.

Dissolving 1g of epoxidized eucommia ulmoides rubber in 25ml of chloroform, heating and stirring in a water bath kettle, then dissolving 1g of epoxy resin in 5ml of ethyl acetate, heating and stirring in the water bath kettle, finally adding 1g of curing agent and 0.02g of defoaming agent, uniformly stirring, coating and curing, and detecting the performance of the coating.

FIG. 1 is a graph of electrochemical analysis of different degrees of epoxidation under the same EEUG/E44, (a) is EEUG/E44 (0.5/1); (b) is EEUG/E44 (1/1). As can be seen from the figure, the proper addition of gutta percha increases the impedance value and enhances the preservative effect. And the influence of the epoxy degree on the performance of the coating can be observed by the same proportion. It can be seen from both (a) and (b) that the epoxy gutta percha with high epoxy degree has higher impedance value under the same matrix proportion, and is better when the proportion of the epoxy gutta percha and the epoxy resin is 0.5: 1. From the electrochemical analysis perspective, the epoxy gutta percha with higher epoxy degree has better anticorrosion effect, but because the impedance difference is smaller, the influence of the epoxy degree on the anticorrosion effect in the electrochemical analysis is small.

FIG. 2 is a graph showing adhesion analysis of different epoxy degrees under the same formulation. The ratio of epoxy gutta-percha to epoxy resin is 0.5:1 and 1:1 respectively. As can be seen from the figure, when the matrix proportion is 0.5:1, the adhesive force with the epoxy degree of 21.1 percent is obviously higher than that with the epoxy degree of 35.8 percent; when the matrix ratio is 1:1, the epoxy degree is low, but the adhesion is high, but the two are not similar. It is obvious that the better proportion of the coating adhesion is 0.5: 1. The influence of the epoxy degree on the coating can be distinguished by properly adding the epoxy gutta-percha, and when less epoxy gutta-percha is added, the difference of the epoxy degree is obvious in the adhesion of the coating; when the amount of epoxy gutta-percha is gradually increased, the influence of the epoxy degree on the adhesion of the coating is small. Therefore, the effect of using the epoxy gutta percha having a low epoxy degree can be seen.

Claims

1. The preparation method of the epoxidized eucommia ulmoides rubber-containing paint is characterized by comprising the following preparation steps of:

firstly, purifying gutta-percha twice, then carrying out gutta-percha epoxidation, testing the epoxy degree of the gutta-percha, then dissolving the prepared epoxidized gutta-percha in a solvent, and heating and stirring the solution; dissolving the resin in a solvent, heating and stirring, finally adding a curing agent and a defoaming agent, and stirring uniformly after ultrasonic oscillation to coat; coating is carried out by changing the epoxy degree of the gutta percha and the proportion of a matrix; keeping a fixed amount of resin in the matrix proportion, and carrying out a coating test by changing the using amount of the epoxidized eucommia rubber;

the resin used is epoxy resin;

the reaction temperature is 45-75 ℃;

the degree of epoxidation is 21.1%;

the mass ratio of the epoxy gutta-percha to the epoxy resin is 0.5: 1.

2. The method for preparing the epoxidized eucommia ulmoides rubber coating according to claim 1, wherein the reaction time is 1.5-3 h.

3. The method for preparing the epoxidized eucommia ulmoides rubber coating according to claim 1, wherein the solvent is one of chloroform, ethyl acetate, toluene and petroleum ether; the mass ratio of the epoxy resin is 10-20 times of that of the epoxy gutta-percha and 3-5 times of that of the resin.

4. The method for preparing the epoxidized eucommia ulmoides rubber coating according to claim 1, wherein the mass ratio of the curing agent is 0.5-0.6 times of that of the matrix, and the mass ratio of the defoaming agent is 1/100 times of that of the matrix.

5. The method for preparing the epoxidized eucommia ulmoides rubber coating according to claim 1, wherein the ultrasonic treatment time is 10-60 min.