阅读说明：本技术 一种苯并噁嗪改性有机硅树脂及其制备方法与应用 (Benzoxazine modified organic silicon resin and preparation method and application thereof ) 是由 辛忠 周长路 于 2019-04-29 设计创作，主要内容包括：本发明公开了一种苯并噁嗪改性有机硅树脂,是由苯并噁嗪官能化硅烷和聚二甲基硅氧烷缩聚制备得到；所述苯并噁嗪改性有机硅树脂的结构式如下：<Image he="475" wi="424" file="DDA0002044417120000011.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>各取代基定义详见说明书。本发明提供了一种新型低成本、低表面能、绿色无氟、耐久度好的苯并噁嗪改性有机硅树脂,与传统氟硅改性相比,苯并噁嗪改性有机硅树脂具有比拟含氟化合物的低表面自由能而不含任何氟原子、成本低廉、环境友好、且具有较好的机械强度、可弥补有机硅机械性能差的不足的特点。(The invention discloses a benzoxazine modified organic silicon resin which is prepared by condensation polymerization of benzoxazine functionalized silane and polydimethylsiloxane; the structural formula of the benzoxazine modified organic silicon resin is as follows: the definition of each substituent is shown in the specification. Compared with the traditional fluorine-silicon modification, the benzoxazine modified organic silicon resin has the characteristics of low surface free energy which is similar to that of a fluorine-containing compound and does not contain any fluorine atom, low cost, environmental friendliness, better mechanical strength and capability of making up the defect of poor mechanical property of organic silicon。)

1. A benzoxazine modified organic silicon resin is characterized in that: is prepared by condensation polymerization of benzoxazine functionalized silane and polydimethylsiloxane;

the structural formula of the benzoxazine modified organic silicon resin is as follows:

R₁is selected from C₁～C₁₈Straight, branched or cyclic alkyl, halogen, phenyl, hydrogen or C substituted by amino, halogen, mercapto or epoxy groups₁～C₁₀One of a linear, branched or cyclic alkyl group;

and x + y is z, wherein z is the number of repeating units from 3 to 200, x is from 5 to 50% of z, and y is from 50 to 95% of z.

2. The benzoxazine-modified silicone resin according to claim 1, wherein: the structure of the benzoxazine-functional silane is as follows:

R₁is selected from C₁～C₁₈Straight, branched or cyclic alkyl, halogen, phenyl, hydrogen or C substituted by amino, halogen, mercapto or epoxy groups₁～C₁₀One of a linear, branched or cyclic alkyl group;

R₂selected from methoxy or ethoxy.

3. The benzoxazine-modified silicone resin according to claim 1, wherein: the polydimethylsiloxane has the following structure:

R₃selected from hydrogen, hydroxyl, methoxyl or ethoxyl, and x is 9-30.

4. A method for producing the benzoxazine-modified silicone resin according to any one of claims 1 to 3, characterized in that: the method comprises the following steps: dissolving benzoxazine functional silane and polydimethylsiloxane in a molar ratio of (5-100): 1 in an organic solvent, adding water and a catalyst, ultrasonically mixing uniformly, coating on a substrate, and performing a hydrolytic condensation reaction to obtain the benzoxazine modified organic silicon resin.

5. The method for preparing a benzoxazine-modified silicone resin according to claim 4, wherein: the organic solvent is at least one of alkanes, substituted alkanes, alcohols, ethers, ketones, esters, amides, pyrrolidones and sulfoxides;

the mole number of the catalyst is 0-10 times that of the benzoxazine-functionalized silane;

the ultrasonic mixing temperature is 25-60 ℃, the time is 15-120 minutes, the frequency is 35 or 53kHz, and the power is 30-100%.

6. The method for preparing a benzoxazine-modified silicone resin according to claim 4, wherein: the temperature of the hydrolysis condensation reaction is 25-150 ℃, and the time is 1-24 h;

the catalyst is selected from one of acid, hydroxide, ammonia or amine;

the base material is one of metal and glass.

7. Use of a benzoxazine-modified silicone resin according to any one of claims 1 to 3 as an antifouling coating.

8. Use of a benzoxazine-modified silicone resin according to claim 7 as an antifouling coating, characterized in that: the method comprises the following steps: and thermally curing the benzoxazine modified organic silicon resin to obtain the polybenzoxazine modified organic silicon resin coating.

9. Use of a benzoxazine-modified silicone resin according to claim 8 as an antifouling coating, characterized in that: the curing temperature of the thermal curing is 150-240 ℃, and the curing time is 0.1-24 h.

10. Use of a benzoxazine-modified silicone resin according to claim 8 as an antifouling coating, characterized in that: the polybenzoxazine modified silicone resin coating has the following repeating structural unit:

R₁is selected from C₁～C₁₈Straight-chain, branched-chain or cyclic alkyl, halogen, phenyl, hydrogen or from amino, halogenMercapto or epoxy substituted C₁～C₁₀One of a linear, branched or cyclic alkyl group;

and x + y is z, wherein z is the number of repeating units from 3 to 200, x is from 5 to 50% of z, and y is from 50 to 95% of z.

Technical Field

The invention belongs to the technical field of organic silicon resin, and particularly relates to benzoxazine modified organic silicon resin and a preparation method and application thereof.

Background

Aquatic animal-planted microorganisms such as barnacles, oysters, ascidians, sea cabbages and green cortex attached to and grown on the surface of marine facilities cause serious biofouling problems to the marine facilities, so that the use performance of equipment is reduced, and the safe and effective operation of the facilities and materials is remarkably reduced. In the case of ships, biofouling can greatly increase the dynamic resistance of the ship's hull. The friction resistance can be increased by more than 10% by a 100-micron-thick biological film, and the resistance can be increased by 80% by a 1-mm-thick biological film, so that the ship speed is reduced by 15%. When the bottom of the ship is seriously polluted by organisms, the thickness of marine organism adhesion can reach more than ten centimeters, and for large commercial ships or military ships with ship bottoms of nearly ten thousand square meters, the ship speed is obviously reduced, and the energy consumption is increased; fouling organisms are attached to equipment such as ship bottom sonar, so that equipment signals are weakened and even fail; oxygen generated by partial attached bacterial metabolites and algae can accelerate electrochemical corrosion of a metal structure, damage the main structure of the offshore facility and seriously influence the performance exertion and safe operation of the offshore engineering facility. Some heat exchange systems adopt seawater cooling, and the water inlet pipe is attached by marine fouling matters, so that the inflow of seawater is reduced, and the heat exchange efficiency is reduced. Numerous undersea engineering facilities such as struts, harbour facilities, fishing nets, ships, coastal industrial facilities have long been plagued with the problem of biofouling.

Marine microorganisms will start to attach themselves to the surface of the installation by physicochemical means. The outermost layer of the microorganism is wrapped with biomacromolecules such as polypeptide and polysaccharide or generates a layer of glue (the forming materials are similar to the polysaccharide and the polypeptide) which is a main substance for adhesion, and the biomacromolecules have strong polarity and are easily adhered to the surface of equipment containing polar groups through hydrogen bonds. Further the biomacromolecules will react with the surface of the device to form a stronger chemical attachment. Hydrophobic surfaces have a lower affinity for marine microorganisms due to the absence of polar groups, so that only van der waals forces exist between the microorganisms and the hydrophobic surface, which adhesion is very weak.

In the last 50 th century, tributyltin self-polishing antifouling paint (TBT-SPC) appeared, and the TBT-SPC rapidly developed with excellent performance and huge cost advantage, occupied more than 70% of antifouling paint market, and obtained huge social and economic benefits. But after being released, the plant growth and reproduction of organisms are strongly interfered, even biogenetic variation is caused, and the plant can enter human bodies through food chains, so that the human health is directly harmed. Under this severe situation, the use of organic tin antifouling paints is restricted by successive actions of countries in the world, and the related products have been completely banned by the International Maritime Organization (IMO) by 2008. The antifouling paint opens the era of low toxicity and no toxicity, and the development of novel paint technology is accelerated in all countries in the world. Although the subsequent alternative tin-free self-polishing antifouling paint alleviates the contradiction between the antifouling requirement and the environmental problem to a certain extent, the antifouling agent containing organic metal (such as zinc, copper and the like) groups is similar to the organic tin action mechanism, the massive enrichment of the antifouling agent is biohazard, and the environmental safety is questionable and questionable. Therefore, the field is in the key stage that old antifouling paint is eliminated and new products are not yet developed, and the development of novel environment-friendly nontoxic antifouling paint is trending. Therefore, the surface property of the material is changed, a novel non-release antifouling coating material is developed, marine organisms are not beneficial to organism attachment in mutual contact with the material, the problem of biofouling can be fundamentally solved, benefit maximization is realized at the minimum environmental cost, and the development of the technology is undoubtedly significant for promoting the development of industries such as ships, marine products, national defense and the like in China.

As mentioned above, the fouling-release (FR) coating with hydrophobic property does not prevent fouling organisms from attaching, but weakens the acting force between the fouling organisms and the coating surface, so that the fouling is peeled off along with the movement of marine facilities or the water flow shearing force generated by mild "carding" equipment, and has good antifouling performance. As is known from the mechanism of action of FR coatings, the surface free energy is the first factor determining their antifouling properties. Long-term biological medicine and marine antifouling research prove that the biological adhesion amount of the coating surface and the critical surface tension (gamma)_c) The empirical relationship between them can be described by a "Baier curve". The analysis curve shows that the lower the surface free energy is, the better the antifouling application is, and the lowest amount of the biofouling is 22 to 24mN · m^-1Within the range. Silicone resins with surface free energies around this range were therefore the material of choice for FR coatings, and Robbart first filed a related patent in 1961 (US 2986474). However, the application of the silicone resin is limited by some defects, such as low mechanical strength, and the performance of the silicone resin is damaged and lost by animal shells or ship anchors and the like in the using process; the hydrophilic sites inside the polymer migrate to the surface and lose hydrophobic properties. Modification of silicone resins or formulations is therefore often required to meet practical requirements. The addition of inorganic fillers (CaCO) to silicone coatings is often required for commercial applications ₃、SiO₂Etc.) or non-reactive silicone oils as a supplement. However, the introduction of these foreign substances causes the loss of the smooth and hydrophobic properties of the coating surface and environmental problems (CaCO3 and silicone oil are gradually dissolved or released into the marine environment). The introduction of organic polymer components such as Polyurethane (PU), epoxy resin, etc. by physical blending or chemical synthesis is another effective way to effectively enhance the performance of silicone resins. The disadvantage of low mechanical strength of the silicone polymer can be overcome while retaining the advantages of low surface energy and high smoothness of the coating (CN205711513U, CN103304762B, etc.). However, the surface energy of the modified materials is high, and the problem of hydrophilic site migration still exists. Based on this, fluorocarbon resin is a strong competitor of modified materials due to good chemical stability, heat resistance, aging resistance and extremely low surface energy (10-20mN · m < -1 >), and fluorosilicone resin has a remarkable effect on enhancing the performance of the coating in all aspects (US6265515B1, WO2007/102741, CN101775144B and CN 103666165B). However, fluoride containing more than 4-CF 2-units is potentially harmful to organisms, the original purpose of green and environment-friendly FR coating is sacrificed, and the high cost also limits the wide range of application.

Therefore, the development of a novel modified organic silicon resin fouling and desorption coating material with low cost, low surface energy, no fluorine and good durability is a key topic derived from national important requirements.

Disclosure of Invention

In order to overcome the problems that the organic silicon resin antifouling material in the prior art is low in mechanical strength and insufficient in hydrophobic durability, and a fluorine-silicon modification mode is high in cost and sacrifices environmental protection, the invention aims to provide the benzoxazine modified organic silicon resin which is low in cost, low in surface energy, green and fluorine-free and good in durability.

The second purpose of the invention is to provide a preparation method of the benzoxazine modified silicone resin.

The third purpose of the invention is to provide an application of the benzoxazine modified organic silicon resin.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows:

the invention provides a benzoxazine-modified organic silicon resin, which is prepared by condensation polymerization of benzoxazine-functionalized silane and polydimethylsiloxane.

The structural formula of the benzoxazine modified organic silicon resin is as follows:

R₁is selected from C₁～C₁₈Straight, branched or cyclic alkyl, halogen, phenyl, hydrogen or C substituted by amino, halogen, mercapto or epoxy groups ₁～C₁₀One of a linear, branched or cyclic alkyl group;

z, z is the number of repeating units from 3 to 200, preferably from 20 to 30, and x is from 5 to 50%, preferably from 10 to 30%, of z; y is 50 to 95%, preferably 70 to 90%, of z.

The structure of the benzoxazine-functional silane is as follows:

R₁is selected from C₁～C₁₈Straight, branched or cyclic alkyl, halogen, phenyl, hydrogen or C substituted by amino, halogen, mercapto or epoxy groups₁～C₁₀One of a linear, branched or cyclic alkyl group;

R₂selected from methoxy or ethoxy.

The polydimethylsiloxane has the following structure:

R₃selected from hydrogen, hydroxyl, methoxyl or ethoxyl, and x is 9-30.

The second aspect of the invention provides a preparation method of the benzoxazine-modified silicone resin, which comprises the following steps: dissolving benzoxazine functional silane and polydimethylsiloxane in a molar ratio of (5-100): 1 in an organic solvent, adding water and a catalyst, ultrasonically mixing uniformly, coating on a substrate, and performing a hydrolytic condensation reaction to obtain the benzoxazine modified organic silicon resin.

The organic solvent is selected from at least one of alkanes, substituted alkanes, alcohols, ethers, ketones, esters, amides, pyrrolidones and sulfoxides, and specifically selected from at least one of chloroform, tetrachloroethane, ethanol, N-butanol, diethylene glycol dimethyl ether, tetrahydrofuran, acetone, ethyl acetate, N-dimethylacetamide, N-methylpyrrolidone and dimethylsulfoxide.

The organic solvent is added in an amount of 1-1000% of the benzoxazine-functional silane.

The water is present in a molar amount of 0.01 to 40 times the benzoxazine-functional silane.

The mole number of the catalyst is 0-10 times, preferably 1-10 times that of the benzoxazine functionalized silane.

The ultrasonic mixing temperature is 25-60 ℃, the time is 15-120 minutes, the frequency is 35 or 53kHz, and the power is 30-100%.

The temperature of the hydrolysis condensation reaction is 25-150 ℃, preferably 25-70 ℃, and the time is 1-24 hours, preferably 2-20 hours.

The catalyst is selected from one of acid, hydroxide, ammonia or amine.

The acid is at least one of acetic acid and hydrochloric acid.

The hydroxide is at least one of sodium hydroxide and potassium hydroxide.

The ammonia or amine is at least one of ammonia water, n-butylamine and triethylamine.

The base material is one of metal and glass, and is specifically selected from an aluminum alloy base material, a glass base material and a stainless steel base material.

The third aspect of the invention provides a use of the benzoxazine-modified silicone resin as an antifouling paint.

The use of the benzoxazine-modified silicone resin as an antifouling coating, comprising the steps of: and thermally curing the benzoxazine modified organic silicon resin to obtain the polybenzoxazine modified organic silicon resin coating which is used as an antifouling coating and mainly used for antifouling fouling and desorption coatings of oceans.

The curing temperature of the thermal curing is 150-240 ℃, and preferably 150-200 ℃; the curing time is 0.1 to 24 hours, preferably 0.5 to 5 hours.

The polybenzoxazine modified silicone resin coating has the following repeating structural unit:

R₁is selected from C₁～C₁₈Straight, branched or cyclic alkyl, halogen, phenyl, hydrogen or C substituted by amino, halogen, mercapto or epoxy groups₁～C₁₀One of a linear, branched or cyclic alkyl group;

z, z is the number of repeating units from 3 to 200, preferably from 20 to 30, and x is from 5 to 50%, preferably from 10 to 30%, of z; y is 50 to 95%, preferably 70 to 90%, of z.

Due to the adoption of the technical scheme, the invention has the following advantages and beneficial effects:

compared with the traditional fluorine-silicon modification, the benzoxazine modified organic silicon resin has the characteristics of low surface free energy which is similar to that of a fluorine-containing compound and does not contain any fluorine atom, low cost, environmental friendliness, better mechanical strength and capability of making up the defect of poor mechanical property of organic silicon.

The coating is prepared by performing condensation polymerization reaction on benzoxazine functional silane and polydimethylsiloxane and then performing a thermosetting process. Therefore, the fluorine-free low-cost benzoxazine modified organic silicon resin can be used as antifouling paint, has excellent antifouling and durable performances, has low surface free energy and good antifouling and fouling desorption performances, and can be equivalent to fluorine-silicon modified resin.

Detailed Description

In order to more clearly illustrate the invention, the invention is further described below in connection with preferred embodiments. It is to be understood by persons skilled in the art that the following detailed description is illustrative and not restrictive, and is not to be taken as limiting the scope of the invention.