阅读说明：本技术 桐油酸马来酸酐改性乙烯基酯树脂及其制备方法和应用 (Tung oil acid maleic anhydride modified vinyl ester resin and preparation method and application thereof ) 是由 杨卓鸿 杨绍恒 方亨 李贵东 于 2021-07-30 设计创作，主要内容包括：本发明属于高分子材料技术领域,具体涉及一种桐油酸马来酸酐改性乙烯基酯树脂及其制备方法和应用。本发明合成了一种三官能度桐油酸马来酸酐作为扩链剂,先将环氧树脂、不饱和一元酸反应进行半封端,再与桐油酸马来酸酐进行增链,最后加入活性稀释剂稀释,得到桐油酸马来酸酐改性乙烯基酯树脂。本发明在含大量苯环结构的环氧树脂中引入含长碳链的桐油酸,可有效地提高热固化膜的拉伸强度与韧性,热固化膜的玻璃化转变温度可以规律性调整,储存稳定性良好,交联密度高。(The invention belongs to the technical field of high polymer materials, and particularly relates to eleostearic acid maleic anhydride modified vinyl ester resin and a preparation method and application thereof. The invention synthesizes a trifunctional eleostearic acid maleic anhydride as a chain extender, wherein epoxy resin and unsaturated monobasic acid are reacted to perform half end capping, then chain extension is performed on the epoxy resin and the unsaturated monobasic acid, and finally an active diluent is added for dilution to obtain the eleostearic acid maleic anhydride modified vinyl ester resin. According to the invention, eleostearic acid containing long carbon chains is introduced into epoxy resin containing a large number of benzene ring structures, so that the tensile strength and toughness of the thermosetting film can be effectively improved, the glass transition temperature of the thermosetting film can be regularly adjusted, the storage stability is good, and the crosslinking density is high.)

1. The eleostearic acid maleic anhydride modified vinyl ester resin is characterized by being prepared from the following raw materials in parts by weight: 4-22 parts of eleostearic acid, 1.6-7.8 parts of maleic anhydride, 150 parts of epoxy resin 140-one, 20-50 parts of ethylenically unsaturated monocarboxylic acid, 80-90 parts of active diluent, 0.9-1.1 parts of catalyst and 0.03-0.04 part of polymerization inhibitor.

2. The maleic elaeostearic acid anhydride modified vinyl ester resin of claim 1, wherein the epoxy resin is any one of a bisphenol a type epoxy resin, a bisphenol F type epoxy resin, or a tetrabromobisphenol a type epoxy resin.

3. The maleic anhydride modified vinyl ester eleostearic acid resin of claim 1, wherein the ethylenically unsaturated monocarboxylic acid is one or a mixture of more than one of acrylic acid, methacrylic acid, crotonic acid and phenylacrylic acid in any proportion.

4. The maleic anhydride modified vinyl ester of eleostearic acid according to claim 1, wherein the reactive diluent is one or a mixture of more than one of styrene, isobornyl acrylate, tripropylene glycol diacrylate and trimethylolpropane triacrylate in any proportion.

5. The vinyl ester resin modified by eleostearic acid maleic anhydride according to claim 1, wherein the catalyst is one or a mixture of more than one of benzyltriethylammonium chloride, triethylamine and triphenylphosphine in any proportion.

6. The vinyl ester resin modified by elaeostearic acid and maleic anhydride as claimed in claim 1, wherein the polymerization inhibitor is one or a mixture of more than one of hydroquinone, p-tert-butyl catechol and catechol in any proportion.

7. The method for preparing a eleostearic acid maleic anhydride modified vinyl ester resin according to any one of claims 1 to 6, comprising the steps of:

(1) performing Diels-Alder addition reaction on the eleostearic acid and maleic anhydride to obtain eleostearic acid maleic anhydride;

(2) under the action of a catalyst and a polymerization inhibitor, the epoxy resin and the ethylenic bond-containing monounsaturated carboxylic acid are blocked, the residual epoxy groups are completely reacted by using eleostearic acid maleic anhydride, and finally, an active diluent is added to obtain the eleostearic acid maleic anhydride modified vinyl ester resin.

8. The method for preparing elaeostearic acid maleic anhydride modified vinyl ester resin as claimed in claim 7, wherein in the step (1), elaeostearic acid is reacted with maleic anhydride at 130-150 ℃ for 3-4 h.

9. The method for preparing the vinyl ester resin modified by the maleic anhydride of eleostearic acid as claimed in claim 7, wherein in the step (2), the epoxy resin, the catalyst, the polymerization inhibitor and the ethylenically unsaturated monocarboxylic acid are reacted at 85-110 ℃ for 2-5 hours until the acid value is less than 30mg KOH/g, then the maleic anhydride of eleostearic acid is added, the reaction is continued at 85-110 ℃ for 2-5 hours until the acid value is less than 30mg KOH/g, then the mixture is cooled to below 80 ℃, and the mixture is diluted by adding the reactive diluent and mixed.

10. Use of a elaeostearic acid maleic anhydride modified vinyl ester resin according to any one of claims 1 to 6 for the preparation of UV coatings, inks or adhesives.

Technical Field

The invention belongs to the technical field of high polymer materials, and particularly relates to eleostearic acid maleic anhydride modified vinyl ester resin and a preparation method and application thereof.

Background

The surface coating is an indispensable industrial product in daily life, can be coated on the surface of a metal, fabric or plastic stool substrate, and mainly plays roles of protecting, insulating, decorating and the like on the substrate material. Coatings can be divided into inorganic coatings and organic coatings, with organic coatings being more common. The most common organic coatings are epoxy resin coatings, polyurethane coatings, and perchloroethylene coatings. In recent years, a new coating, a vinyl ester coating, has emerged by modifying epoxy resin coatings.

Vinyl ester resins are generally obtained by ring-opening addition of epoxy resins and monounsaturated carboxylic acids, and then dissolving them in unsaturated reactive monomers. From the structure, firstly, because the double bond participating in the free radical curing is positioned at the end position of the molecular chain segment, the curing activity is high, and the molding is easy; secondly, the common epoxy resin is bisphenol A structure, and the main chain has more rigid benzene ring structures, so that the cured film has high tensile strength. At present, chain extenders commonly used for vinyl ester resins are mostly bifunctionality, finally obtained resins are linear structures, and the resins of the type have low curing activity, easy surface stickiness and poor mechanical properties. In order to improve the mechanical properties of vinyl ester resins, in the prior art, the polymerization degree of the vinyl ester resins is generally increased, for example, CN103304749A uses long-chain saturated dibasic acid to partially replace unsaturated monocarboxylic acid to toughen the vinyl ester resins through chain extension reaction with epoxy resins, and the chain extension reaction of polymethylene polyphenyl isocyanate is performed after the vinyl ester resins are diluted in a cross-linking agent solution, so that the obtained copolymer has higher molecular weight than that of the common epoxy vinyl ester resins, excellent mechanical properties and good corrosion resistance. However, the toughness is not enough, and the oil is excessively dependent on petroleum resources, which is not beneficial to environmental protection.

Disclosure of Invention

According to the first aspect of the invention, the maleic anhydride modified vinyl ester eleostearate resin is prepared from the following raw materials in parts by weight: 4-22 parts of eleostearic acid, 1.6-7.8 parts of maleic anhydride, 150 parts of epoxy resin 140-one, 20-50 parts of ethylenically unsaturated monocarboxylic acid, 80-90 parts of active diluent, 0.9-1.1 parts of catalyst and 0.03-0.04 part of polymerization inhibitor.

In some embodiments, the epoxy resin is any one of a bisphenol a type epoxy resin, a bisphenol F type epoxy resin, or a tetrabromobisphenol a type epoxy resin.

In some embodiments, the ethylenically unsaturated monocarboxylic acid is one or a mixture of more than one of acrylic acid, methacrylic acid, crotonic acid and phenylacrylic acid in any proportion.

In some embodiments, the reactive diluent is one or a mixture of more than one of styrene, isobornyl acrylate, tripropylene glycol diacrylate and trimethylolpropane triacrylate in any proportion.

In some embodiments, the catalyst is one or a mixture of more than one of benzyltriethylammonium chloride, triethylamine and triphenylphosphine in any proportion.

In some embodiments, the polymerization inhibitor is one or a mixture of more than one of hydroquinone, p-tert-butylcatechol and catechol in any proportion.

According to another aspect of the present invention, there is provided a method for preparing the maleic anhydride modified vinyl ester eleostearic acid resin, comprising the following steps:

(1) performing Diels-Alder addition reaction on the eleostearic acid and maleic anhydride to obtain eleostearic acid maleic anhydride;

(2) under the action of a catalyst and a polymerization inhibitor, the epoxy resin and the ethylenic bond-containing monounsaturated carboxylic acid are blocked, the residual epoxy groups are completely reacted by using eleostearic acid maleic anhydride, and finally, an active diluent is added to obtain the eleostearic acid maleic anhydride modified vinyl ester resin.

According to the invention, chain extension modification is carried out on eleostearic acid maleic anhydride and epoxy resin to obtain vinyl ester resin, and then the thermosetting vinyl ester resin is obtained through double-bond free radical curing. Specifically, a trifunctional eleostearic acid maleic anhydride is synthesized as a chain extender, then epoxy resin and unsaturated monobasic acid are reacted to perform half-end capping, then chain extension is performed on the epoxy resin and eleostearic acid maleic anhydride, and finally a reactive diluent is added for dilution to obtain the eleostearic acid maleic anhydride modified vinyl ester resin. According to the invention, eleostearic acid containing long carbon chains is introduced into epoxy resin containing a large number of benzene ring structures, so that the tensile strength and toughness of the thermosetting film can be effectively improved, the glass transition temperature of the thermosetting film can be regularly adjusted, the storage stability is good, and the crosslinking density is high.

Eleostearic acid has a conjugated double bond structure and a carboxylic acid structure, the conjugated double bond structure can be modified through Diels-Alder addition reaction, a new functional group is introduced, and the carboxylic acid structure can participate in the ring opening of epoxy. In addition, the eleostearic acid has a longer bio-based carbon chain, so that the toughness of the vinyl ester resin can be improved.

In some embodiments, in step (1), eleostearic acid is reacted with maleic anhydride at 130-150 ℃ for 3-4 h. The reaction product is tested and infrared is observed, and the conjugated double bond peak disappears completely to reach the reaction end point. And adding ethyl acetate into the obtained reaction product for dissolving, washing with deionized water until the effluent liquid is neutral, and then performing rotary evaporation at 45 ℃ to remove the ethyl acetate to obtain brownish red transparent eleostearic acid maleic anhydride. Wherein the dosage ratio of eleostearic acid to maleic anhydride is 1 mol: (1.0-1.5) mol, preferably 1 mol: (1.0-1.2) mol.

In some embodiments, in the step (2), the epoxy resin, the catalyst, the polymerization inhibitor and the ethylenically unsaturated monocarboxylic acid are reacted at 85-110 ℃ for 2-5 hours until the acid value is less than 30mg KOH/g, then eleostearic acid maleic anhydride is added, the reaction is continued at 85-110 ℃ for 2-5 hours until the acid value is less than 30mg KOH/g, then the mixture is cooled to below 80 ℃, the reactive diluent is added for dilution, and the mixture is uniformly mixed. Wherein the dosage ratio of the epoxy resin, the ethylenic bond-containing monounsaturated carboxylic acid and the eleostearic acid maleic anhydride is 1 mol: (1.10-1.85) mol: (0.05-0.30) mol, preferably 1 mol: (1.55-1.70) mol: (0.10-0.15) mol.

In some embodiments, in step (2), the catalyst is used in an amount of 0.4 to 2.0 wt%, preferably 0.4 to 1.0 wt%, based on the total mass of the epoxy resin, the eleostearic acid maleic anhydride, and the ethylenically unsaturated monobasic acid.

In some embodiments, in step (2), the amount of the polymerization inhibitor is 0.015 to 0.05 wt%, preferably 0.015 to 0.025 wt%, based on the total mass of the epoxy resin, the maleic anhydride of eleostearic acid, and the ethylenically unsaturated monobasic acid.

According to a further aspect of the invention, there is provided the use of the maleic anhydride eleostearic acid modified vinyl ester resin described above in the preparation of UV coatings, inks or adhesives.

Has the advantages that:

according to the invention, the tung oil-based chain extender containing long carbon chains is introduced into the petroleum-based epoxy resin, the petroleum-based epoxy resin with high hardness and poor toughness and the bio-based resin with good toughness and low hardness are combined through the ring-opening reaction of epoxy and carboxylic acid, and the tung oil acid maleic anhydride has a trifunctional structure, so that the crosslinking density of the resin can be improved, and the resin can keep high hardness while the toughness is increased. With the different consumption of the maleic anhydride of the eleostearic acid, the glass transition temperature of the thermosetting film shows regular change, so that the glass transition temperature of the thermosetting film can be regularly regulated and controlled. The resin prepared by the invention has uniform appearance, no delamination and low viscosity, and is suitable for being applied to preparation of UV coating, printing ink or adhesive.

Drawings

FIG. 1 is a reaction scheme of step (1) of example 1 of the present invention.

FIG. 2 is a reaction scheme of step (2) of example 1 of the present invention.

Fig. 3 is a fourier transform infrared spectrum of eleostearic acid, eleostearic acid maleic anhydride in example 1 of the present invention.

FIG. 4 is a Fourier transform infrared spectrum of the epoxy resin and the maleic anhydride eleostearic acid modified vinyl ester resin in example 1 of the present invention.

Detailed Description

The present invention will be described in further detail with reference to specific examples, but the embodiments of the present invention are not limited thereto. The starting materials referred to in the following examples are commercially available.

Example 1

The preparation method of the eleostearic acid maleic anhydride modified vinyl ester resin comprises the following steps:

(1) 239.26g of eleostearic acid and 84.66g of maleic anhydride are put into a 1000mL round-bottom flask, magnetic stirring is carried out, the temperature is increased to 140 ℃, the reaction is kept for 3.5 hours, and the reaction end point is reached when the conjugated double bond peak is completely disappeared by infrared test observation. Then, 300g of ethyl acetate was put into the round-bottom flask to dissolve the solution, and the solution was transferred to a separatory funnel and washed with deionized water until the effluent was neutral. And then, carrying out rotary evaporation on the organic phase at the temperature of 45 ℃ to remove the solvent, thus obtaining the brownish red transparent eleostearic acid maleic anhydride. The reaction scheme of this step is shown in FIG. 1.

(2) 145.68g of bisphenol A epoxy resin E-44 (molecular weight of 454), 42.66g of acrylic acid, 0.0389g of hydroquinone as a polymerization inhibitor and 0.9718g of benzyltriethylammonium chloride as a catalyst are put into a 1000mL round-bottom flask, and the temperature is raised to 90 ℃ for reaction until the acid value is less than 30 mgKOH/g. Then 6.02g of eleostearic acid maleic anhydride was added and reacted at 90 ℃ until the acid value was less than 30 mgKOH/g. Then cooling to below 80 ℃, adding 83.30g of styrene, and uniformly mixing to obtain the light yellow transparent eleostearic acid maleic anhydride modified vinyl ester resin. The reaction scheme of this step is shown in FIG. 2.

The fourier transform infrared spectrums of eleostearic acid and eleostearic acid maleic anhydride of the present example are shown in fig. 3, and the fourier transform infrared spectrums of epoxy resin and eleostearic acid maleic anhydride modified vinyl ester resin are shown in fig. 4.

As can be seen from a comparison of FIG. 3, the starting material is eleostearic acid (noted TOA) and the product is eleostearic acid maleic anhydride (noted TOA-MA). Specifically, the method comprises the following steps:

seen in TOA at 3500cm^-1To 2300cm^-1The long peak of (A) is O-H stretching vibration on carboxylic acid, 992cm^-1The bending vibration of the conjugated double bond indicates that the TOA has two functional groups of carboxylic acid and the conjugated double bond. 992cm in TOA-MA after Diels-Alder addition of TOA to maleic anhydride (described as MA)^-1The peak of conjugated double bond of (2) disappears, and 1848 and 1778cm newly appear^-1Two sets of peaks, representing the stretching vibration of C ═ O on the anhydride, indicate that the Diels-Alder addition reaction was successful and maleic anhydride was successfully ligated with eleostearic acid. Therefore, the FT-IR result shows that the product is eleostearic acid maleic anhydride.

From a comparison of FIG. 4, it can be seen that the starting material is an epoxy resin (noted EP) and the product is a maleic anhydride modified vinyl ester resin (noted VER) of eleostearic acid. Specifically, the method comprises the following steps:

in EP it is seen at 915cm^-1The characteristic peak appeared nearby is the epoxy vibration peak, 1607cm^-1Is the stretching vibration of C ═ C on a benzene ring, 830cm^-1Is the opposite substitution vibration absorption peak on the benzene ring. After a series of ring-opening blocking reactions, 915cm are seen in the VER^-1The characteristic peak of epoxy group disappears, which indicates that the epoxy group reacts with carboxylic acid to complete ring opening, 1724cm^-1The peak is the stretching vibration peak of C ═ O on the ester bond of the end-capped unsaturated monobasic acid. Therefore, the FT-IR result shows that the product is the tung oil acid maleic anhydride modified vinyl ester resin.

Example 2

The preparation method of the eleostearic acid maleic anhydride modified vinyl ester resin comprises the following steps:

(1) 230.36g of eleostearic acid and 90.00g of maleic anhydride are put into a 1000mL round-bottom flask, magnetic stirring is carried out, the temperature is increased to 140 ℃, the reaction is kept for 3.5 hours, and the reaction end point is reached when the conjugated double bond peak is completely disappeared by infrared test observation. Adding 300g of ethyl acetate into a round-bottom flask for dissolving, transferring the solution into a separating funnel, washing with deionized water until the effluent liquid is neutral, and performing rotary evaporation on the organic phase at 45 ℃ to remove the solvent to obtain brownish red transparent eleostearic acid maleic anhydride.

(2) 145.68g of bisphenol A epoxy resin E-44 (molecular weight of 454), 39.20g of acrylic acid, 0.0394g of polymerization inhibitor hydroquinone and 0.9846g of catalyst benzyltriethylammonium chloride are put into a 1000mL round-bottom flask, and the temperature is raised to 90 ℃ for reaction until the acid value is less than 30 mgKOH/g. Then 12.04g maleic eleostearic acid anhydride was added and the reaction was carried out at 90 ℃ until the acid value was less than 30 mgKOH/g. Then cooling to below 80 ℃, adding 84.39g of styrene, and uniformly mixing to obtain the light yellow transparent eleostearic acid maleic anhydride modified vinyl ester resin.

The tung oil acid maleic anhydride and the tung oil acid maleic anhydride modified vinyl ester resin obtained in the embodiment are subjected to Fourier transform infrared spectrogram detection, the characteristic peak of the detection result is basically consistent with that of the embodiment 1, and details are not repeated here for saving space.

Example 3

The preparation method of the eleostearic acid maleic anhydride modified vinyl ester resin comprises the following steps:

(1) 239.26g of eleostearic acid and 84.66g of maleic anhydride are put into a 1000mL round-bottom flask, magnetic stirring is carried out, the temperature is increased to 140 ℃, the reaction is kept for 4 hours, and the reaction end point is reached when the conjugated double bond peak is completely disappeared by infrared test observation. Adding 300g of ethyl acetate into a round-bottom flask for dissolving, transferring the solution into a separating funnel, washing with deionized water until the effluent liquid is neutral, and performing rotary evaporation on the organic phase at 45 ℃ to remove the solvent to obtain brownish red transparent eleostearic acid maleic anhydride.

(2) 145.68g of bisphenol A epoxy resin E-44 (molecular weight of 454), 35.74g of acrylic acid, 0.0399g of hydroquinone as a polymerization inhibitor and 0.9974g of benzyltriethylammonium chloride as a catalyst are put into a 1000mL round-bottom flask, and the temperature is raised to 90 ℃ for reaction until the acid value is less than 30 mgKOH/g. Then 18.09g of maleic elaeostearic anhydride was added and the reaction was carried out at 90 ℃ until the acid value was less than 30 mgKOH/g. Then cooling to below 80 ℃, adding 85.49g of styrene, and uniformly mixing to obtain the light yellow transparent eleostearic acid maleic anhydride modified vinyl ester resin.

The check of the tung oil acid maleic anhydride and the tung oil acid maleic anhydride modified vinyl ester resin of the embodiment by the fourier transform infrared spectrogram, the characteristic peak of the obtained check result is basically consistent with that of the embodiment 1, and the details are not repeated herein for saving space.

Example 4

The preparation method of the eleostearic acid maleic anhydride modified vinyl ester resin comprises the following steps:

(1) 239.26g of eleostearic acid and 84.66g of maleic anhydride are put into a 1000mL round-bottom flask, magnetic stirring is carried out, the temperature is increased to 140 ℃, the reaction is kept for 3 hours, and the reaction end point is reached when the conjugated double bond peak is completely disappeared by infrared test observation. Adding 300g of ethyl acetate into a round-bottom flask for dissolving, transferring the solution into a separating funnel, washing with deionized water until the effluent liquid is neutral, and performing rotary evaporation on the organic phase at 45 ℃ to remove the solvent to obtain brownish red transparent eleostearic acid maleic anhydride.

(2) 145.68g of bisphenol A epoxy resin E-44 (molecular weight of 454), 32.28g of acrylic acid, 0.0404g of hydroquinone as a polymerization inhibitor and 1.0102g of benzyltriethylammonium chloride as a catalyst are put into a 1000mL round-bottom flask, and the temperature is raised to 90 ℃ for reaction until the acid value is less than 30 mgKOH/g. Then 24.08g of eleostearic acid maleic anhydride is added and reacted at 90 ℃ until the acid value is less than 30 mgKOH/g. Then cooling to below 80 ℃, adding 86.59g of styrene, and uniformly mixing to obtain the light yellow transparent eleostearic acid maleic anhydride modified vinyl ester resin.

The characteristic peak of the detection result obtained by performing fourier transform infrared spectrogram detection on the eleostearic acid maleic anhydride and eleostearic acid maleic anhydride modified vinyl ester resin in the embodiment is basically consistent with that of the embodiment 1, and is not repeated herein for saving space.

Example 5

The preparation method of the eleostearic acid maleic anhydride modified vinyl ester resin comprises the following steps:

(1) 239.26g of eleostearic acid and 84.66g of maleic anhydride are put into a 1000mL round-bottom flask, magnetic stirring is carried out, the temperature is increased to 140 ℃, the reaction is kept for 5 hours, and the reaction end point is reached when the conjugated double bond peak is completely disappeared by infrared test observation. Adding 300g of ethyl acetate into a round-bottom flask for dissolving, transferring the solution into a separating funnel, washing with deionized water until the effluent liquid is neutral, and performing rotary evaporation on the organic phase at 45 ℃ to remove the solvent to obtain brownish red transparent eleostearic acid maleic anhydride.

(2) 145.68g of bisphenol A epoxy resin E-44 (molecular weight of 454), 28.82g of acrylic acid, 0.0409g of polymerization inhibitor hydroquinone and 1.0230g of catalyst benzyltriethylammonium chloride are put into a 1000mL round-bottomed flask, and the temperature is raised to 90 ℃ for reaction until the acid value is less than 30 mgKOH/g. Then 30.10g of eleostearic acid maleic anhydride was added and reacted at 90 ℃ until the acid value was less than 30 mgKOH/g. Then cooling to below 80 ℃, adding 87.69g of styrene, and uniformly mixing to obtain the light yellow transparent eleostearic acid maleic anhydride modified vinyl ester resin.

The check of the tung oil acid maleic anhydride and the tung oil acid maleic anhydride modified vinyl ester resin of the embodiment by the fourier transform infrared spectrogram, the characteristic peak of the obtained check result is basically consistent with that of the embodiment 1, and the details are not repeated herein for saving space.

Comparative example 1

The preparation method of the fumaric acid modified vinyl ester resin of the comparative example comprises the following steps:

(1) 145.68g of bisphenol A epoxy resin E-44 (molecular weight of 454), 28.82g of acrylic acid, 0.0409g of polymerization inhibitor hydroquinone and 1.0230g of catalyst benzyltriethylammonium chloride are put into a 1000mL round-bottomed flask, and the temperature is raised to 90 ℃ for reaction until the acid value is less than 30 mgKOH/g. Then, 3.71g of fumaric acid was added, and the reaction was carried out at 90 ℃ until the acid value was less than 30 mgKOH/g. Then cooling to below 80 ℃, adding 87.69g of styrene, and uniformly mixing to obtain the fumaric acid modified vinyl ester resin.

In order to detect the comprehensive mechanical property and thermal stability of the eleostearic acid maleic anhydride modified vinyl ester resin prepared by the invention, the eleostearic acid maleic anhydride modified vinyl ester resin prepared in examples 1-5 and the fumaric acid modified vinyl ester resin prepared in comparative example 1 are prepared into resin thermosetting films, and then the obtained resin thermosetting films are subjected to a plastic tensile property test, a dynamic thermal mechanical property test, a plastic bending property test and a thermal gravimetric test.

1. Preparation of resin thermosetting film

Uniformly mixing the elaeostearic acid maleic anhydride modified vinyl ester resin prepared in the examples 1-5 and the fumaric acid modified vinyl ester resin prepared in the comparative example 1 with an accelerator respectively, adding a curing agent, uniformly mixing, removing bubbles in vacuum, pouring into a silica gel mold, curing at room temperature for 24 hours, and then placing in an oven at 100 ℃ for curing for 3-6 hours to obtain the product. Wherein the accelerant is cobalt naphthenate, and the dosage of the accelerant is about 0.3 wt% of the total mass of eleostearic acid maleic anhydride modified vinyl ester resin or fumaric acid modified vinyl ester resin. The curing agent is methyl ethyl ketone peroxide, and the dosage of the curing agent is about 1.0 wt% of the total mass of the eleostearic acid maleic anhydride modified vinyl ester resin or the fumaric acid modified vinyl ester resin.

2. Performing plastic tensile property test, dynamic thermal mechanical property test, plastic bending property test and thermogravimetric test on the thermosetting film

(1) Testing the tensile property of the plastic: the tensile test was carried out using an AGS-X1 kN universal tester from Shimadzu corporation. The specification of the dumbbell-shaped sample is referred to GB/T1040.2-2006, and the crosshead speed is 1mm & min^-1. Young's modulus is the ratio of tensile strength to elongation at break.

For accuracy, three measurements were made for each sample and averaged.

(2) Dynamic thermomechanical property test: using a Netzsch DMA 242E dynamic thermodynamics instrument, the stretching mode was selected and the oscillation frequency was set to 1 Hz. The sample is first cooled to-80 deg.C with liquid nitrogen and held at-50 deg.C for 3 min, then at 5 deg.C/min^-1Is heated to 180 ℃. The specification of the sample is 32mm × 5mm × 3mm (length × width × thickness). The glass transition temperature (Tg) of the thermosetting film takes a value corresponding to the temperature of the peak on the temperature curve of tan δ.

For accuracy, three measurements were made for each sample and averaged.

(3) And (3) testing the bending property of the plastic: the bending test was carried out using an AGS-X1 kN universal tester from Shimadzu corporation. The sample specification is referred to GB/T9341-^-1. The flexural modulus is the ratio of the flexural strength to the flexural modulus at break.

For accuracy, three measurements were made for each sample and averaged.

(4) Thermogravimetric test method: the following thermogravimetric analysis test was performed using a thermal analyzer model NetzschSTA 449C. The temperature range required for the thermogravimetric testing of the sample was set at 35-650 ℃ with a heating rate of 10 ℃ min^-1The nitrogen environment is kept in the test process, and the nitrogen introducing speed is 60 mL/min^-1。

For accuracy, three measurements were made for each sample and averaged.

The comprehensive mechanical property results of the thermosetting film are shown in table 1, and the thermal stability results are shown in table 2.

TABLE 1 comprehensive mechanical Property results for thermoset films

TABLE 2 thermal stability results for thermally cured films

As can be seen from Table 1, after the resin is modified by adding the maleic anhydride eleostearate, compared with the conventional fumaric acid modified vinyl ester resin, the tensile property, the bending property and the glass transition temperature of the resin are improved to a certain extent, the tensile property, the bending property and the glass transition temperature are reduced to a certain extent after the resin reaches a peak value, and the addition amount of the maleic anhydride eleostearate corresponding to the peak value is about 5-15%. The reason for this is probably that, due to the addition of the maleic anhydride eleostearic acid, the original linear polymer structure is changed into a reticular polymer structure, and the increase of the crosslinking density can improve the mechanical property; however, when maleic anhydride eleostearate is continuously added, the mechanical properties are reduced due to excessive introduced long carbon chains.

As can be seen from Table 2, with the addition of maleic anhydride eleostearic acid, although a long biobased carbon chain was introduced, the decrease in thermal stability of the resin was not significant due to the increase in crosslinking density, and T was_10％All are higher than 369 ℃, which shows that the resin has better thermal stability.

The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.