A bio-based epoxy-based glassy polymer material modified by siloxane and a preparation method thereof

Abstract

The application provides a brand-new epoxy-based glass polymer material modified by siloxane and a preparation method, wherein vanillin is used to react with different diamine compounds to prepare a vanillyl diphenol compound, the diphenol compound is used to react with different epoxies to obtain a vanillyl epoxy compound, 3-aminopropyl triethoxysiloxane is introduced for crosslinking and solidification on the basis, an epoxy-based glass polymer material is prepared through a gradient temperature solidification method, and a large number of dynamic imine bonds and siloxane bonds in the material can enhance the mechanical properties, thermal stability and creep resistance of the epoxy-based glass polymer material. In addition, in the design of the application, experimental raw materials are green and environmentally friendly, the epoxy-based glass polymer material has excellent mechanical properties, thermal stability and creep resistance, is an excellent option for preparing green materials, and provides a train of thought for preparing the epoxy-based glass polymer material by using a green method.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of high polymer material industry, and in particular to a kind of siloxane modified bio-based epoxy glass high polymer material and preparation method. BACKGROUND

[0002] At present, in self-healing chemistry, epoxy self-healing is the most studied system. Epoxy self-healing is generally crosslinked by epoxy-containing compounds and amine or anhydride curing agents. The cured epoxy self-healing has excellent mechanical properties, heat resistance, chemical resistance, and dimensional stability. However, most of the reported epoxy self-healing uses petroleum chemical products as raw materials. With the gradual improvement of people's concept of sustainable development and environmental awareness, biomass resources have attracted more and more attention. Bio-based polymer materials are a kind of sustainable polymer materials synthesized from renewable resources through physical, chemical or biological processes. At present, some bio-based polymer materials based on plant oils, vanillin, eugenol, muuene and isosorbide have been widely reported. Bio-based epoxy resin has attracted more and more attention due to its easy availability, low price and biodegradability. Siloxane is concerned due to its unique properties such as low glass transition, high failure strain, low surface energy, excellent thermal stability and so on.

[0003] Glass-like polymer materials are based on covalent adaptive networks, which are formed by dynamic covalent bond cross-linked network topology structure, and have the advantages of both thermosetting materials and thermoplastic materials. Dynamic covalent bond is a specific chemical bond that can reversibly break and reconfigure under external stimulus, allowing thermosetting materials to be reprocessed and recycled. Glassy polymers are expected to solve the environmental pollution and resource waste caused by the inability of traditional thermosetting polymers to be recycled. Because this material can rearrange the network under external stimulus, it can exhibit reworkability, reshaping, plastic deformation, shape memory and other characteristics. However, the existing glass-like polymer materials are not environmentally friendly, and there is no method for preparing epoxy glass-like polymer materials from vanillin in the research field. SUMMARY

[0004] In view of the problems in the prior art, the present application provides a kind of siloxane modified bio-based epoxy glass high polymer material and preparation method, based on the bisphenol compound generated from vanillin, which has excellent mechanical properties and good mechanical properties of bio-based, green epoxy glass high polymer material, providing a new idea for the preparation of epoxy glass high polymer material.

[0005] The present application is realized by the following technical solutions:

[0006] A preparation method of a bio-based epoxy-based glassy polymer material modified by siloxane, characterized in that it comprises:

[0007] S1, dissolving a diamine compound and vanillin in methanol, heating and reacting in a water bath under a nitrogen atmosphere, and then treating the obtained product to obtain a vanillyl binary phenol compound;

[0008] S2, dissolving the vanillyl binary phenol compound and an epoxy compound in DMF, heating and reacting in an oil bath under a nitrogen atmosphere to obtain a preliminary prepolymer;

[0009] S3, adding 3-aminopropyl triethoxysiloxane to the preliminary prepolymer, adding KOH after a period of oil bath reaction, and stopping the reaction when the solution becomes viscous or bubbles appear, to prepare a bio-based epoxy-based glassy polymer material;

[0010] Preferably, the molar ratio of the diamine compound to vanillin in S1 is 1:2, and the total addition amount of the diamine compound and vanillin in S1 accounts for 20 wt%-60 wt% of methanol.

[0011] Preferably, the molar ratio of the active H of the vanillyl binary phenol compound to the epoxy group of the epoxy compound in S2 is 1:1.

[0012] Preferably, the molar ratio of the epoxy group of the vanillyl epoxy compound to the active H of 3-aminopropyl triethoxysiloxane in S3 is 1:1.

[0013] Preferably, the reaction temperature in S1 is 70 ℃, the reaction time is 6h, the reaction temperature in S2 is 90-120 ℃, and the reaction time is 3-5h; the reaction temperature in S3 is 120-130 ℃, and the reaction time is 1-2h.

[0014] Preferably, the diamine compound includes one of hexanediamine, p-phenylenediamine, and 4,4'-diaminodiphenyl methane.

[0015] Preferably, the epoxy compound is one of glycerol triglycidyl ether epichlorohydrin.

[0016] Preferably, the bio-based epoxy-based glassy polymer material obtained in S3 is cured at a temperature of 60 ℃ for 2h, at a temperature of 80 ℃ for 3h, and at a temperature of 120 ℃ for 1h.

[0017] Preferably, after the preliminary synthesized prepolymer in S3 is reacted in an oil bath for a period of time, KOH is added to catalyze the formation of Si-O-Si bonds, and the reaction is stopped when the solution becomes viscous or bubbles appear, to prepare a bio-based epoxy-based glassy polymer material.

[0018] A preparation method of a siloxane-modified bio-based epoxy-based glass polymer material is prepared by the preparation method.

[0019] Compared with the prior art, the present application has the following beneficial technical effects:

[0020] The present application provides a new preparation method of a bio-based epoxy-based glass polymer material containing siloxane bonds. The method uses readily available vanillin as a basic raw material and reacts with different diamine compounds to prepare a vanillyl diphenol compound. The vanillyl diphenol compound is then reacted with an epoxy compound to obtain a vanillyl epoxy compound. On this basis, 3-aminopropyl triethoxysiloxane is introduced for curing. A bio-based, recyclable and extensible epoxy-based glass polymer material is prepared by a gradient temperature curing method. The large number of dynamic imine bonds and siloxane bonds in the material can enhance the mechanical properties, thermal stability and creep resistance of the epoxy-based glass polymer. The benzene ring structure in the vanillyl diphenol compound can increase the rigidity and thermal stability of the material. The long flexible chain segment in the coupling agent can impart softness and tensile resistance to the material. In addition, the experimental raw materials in the design of the present application are green and environmentally friendly. The epoxy-based glass polymer material has excellent mechanical properties, thermal stability and creep resistance, making it an excellent option for preparing green materials. The present application provides a new idea for preparing epoxy-based glass polymer materials using green methods.

[0021] Further, the present application introduces imine bonds by using self-made vanillyl epoxy compounds to enhance the mechanical properties and thermal stability of the epoxy-based glass polymer material. The use of plant-based materials makes the obtained epoxy-based glass polymer material have excellent biodegradability. The imine bond exchange and siloxane bond exchange reactions obtained through dynamic reversible reactions involving biomass give the glass-like polymer material the characteristics of repeatable processing and recyclability. This work promotes the types of epoxy-based glass polymers, making them promising candidates for repairable and recyclable adhesives. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 The reaction process diagram for Examples 1 to 3;

[0023] Figure 2 The reaction process diagram for Examples 4 to 6. DETAILED DESCRIPTION

[0024] The present application will be further described in detail below in conjunction with specific examples, which are an explanation of the present application rather than a limitation.

[0025] The present application is based on siloxane compounds for modification and preparation of a bio-based glass-like polymer material containing siloxane bonds.

[0026] The technical solution adopted in this invention is as follows: First, a diamine and vanillin are added in a 1:2 molar ratio to a three-necked flask equipped with an electric stirrer, a pure nitrogen protection device inlet, and a reflux condenser. Methanol is then added, and the reaction is carried out in a water bath at 70°C for 4-6 hours. The resulting product is filtered, recrystallized three times with methanol, and dried to obtain the vanillyl diphenol compound. Second, a vanillyl diphenol compound and an epoxy compound in a 1:1 molar ratio are dissolved in DMF and added to a 250 mL three-necked flask equipped with a reflux condenser, an electric stirrer, and a thermometer. The reaction is carried out at 90-120°C for 3-5 hours to obtain a preliminary prepolymer. Third, 3-aminopropyltriethoxysiloxane is added to the preliminary prepolymer for reaction. After a period of reaction, KOH is added. The reaction ends when the solution becomes viscous or bubbles appear, thus preparing a bio-based epoxy glass polymer material.

[0027] The diamine is one of hexamethylenediamine, p-phenylenediamine, and 4,4'-diaminodiphenylmethane.

[0028] The epoxy compound is one of glycerol triglycidyl ether and epichlorohydrin.

[0029] The obtained bio-based epoxy glass polymer material was cured at 50 °C for 2 hours, cured at 80 °C for 3 hours, and cured at 120 °C for 1 hour.

[0030] Reaction equation:

[0031] 1. Reaction equation for vanillyl diphenol compounds

[0032]

[0033] Example 1:

[0034] like Figure 1 As shown, step one: 60.8 g (0.4 mol) vanillin and 21.6 g (0.2 mol) p-phenylenediamine were dissolved in 70 mL and 30 mL of methanol, respectively. These were then added to a three-necked flask equipped with an electric stirrer, a pure nitrogen inlet, and a reflux condenser. The reaction was carried out in a water bath at 70 °C for 6 hours. The resulting product was filtered to obtain yellow crystals, which were then washed three times with methanol and dried to finally obtain the vanillyl diphenol compound.

[0035] Step two: 28.2 g (0.075 mol) of vanillyl diphenol compound and 26.0 g (0.1 mol) of glycerol triglycidyl ether were dissolved in 100 mL of DMF, added to a 250 mL three-necked flask with a stirring device, and reacted at 90-120 °C in an oil bath for 5 h to obtain a preliminary prepolymer.

[0036] Step three: 16.6 g (0.075 mol) of 3-aminopropyl triethoxysiloxane was added to the preliminary prepolymer, and the temperature was raised to 130 °C for 1 h. KOH was added, and manual stirring was performed. When the solution became viscous or bubbles were emitted, the reaction was stopped, and the reaction mixture was quickly poured into a polytetrafluoroethylene (PTFE) mold for solidification.

[0037] Step four: The reaction mixture was pre-solidified at 50 °C for 2 h, solidified at 80 °C for 3 h, and post-solidified at 120 °C for 1 h, finally obtaining a bio-based epoxy glass high molecular film.

[0038] Example two:

[0039] As shown in Figure 1 Step one: 60.8 g (0.4 mol) of vanillin and 23.2 g (0.2 mol) of hexanediamine were respectively dissolved in 70 mL and 30 mL of methanol. Subsequently, they were added to a three-necked flask equipped with an electric stirrer, a pure nitrogen gas protection device inlet, and a reflux condenser device, and reacted in a 70 °C water bath. After 6 h of reaction, the obtained product was suction filtered to obtain yellow crystals, which were washed with methanol three times, and dried to finally obtain the product, vanillyl diphenol compound.

[0040] Step two: 28.8 g (0.075 mol) of vanillyl diphenol compound and 26.0 g (0.1 mol) of glycerol triglycidyl ether were dissolved in 100 mL of DMF, added to a 250 mL three-necked flask with a stirring device, and reacted at 90-120 °C in an oil bath for 5 h to obtain a preliminary prepolymer.

[0041] Step three: 16.6 g (0.075 mol) of 3-aminopropyl triethoxysiloxane was added to the preliminary prepolymer, and the temperature was raised to 130 °C for 1 h. KOH was added, and manual stirring was performed. When the solution became viscous or bubbles were emitted, the reaction was stopped, and the reaction mixture was quickly poured into a polytetrafluoroethylene (PTFE) mold for solidification.

[0042] Step four: The reaction mixture was pre-solidified at 50 °C for 2 h, solidified at 80 °C for 3 h, and post-solidified at 120 °C for 1 h, finally obtaining a bio-based epoxy glass high molecular film.

[0043] Example three:

[0044] As shown in Figure 1 Step one: 60.8 g (0.4 mol) of vanillin and 39.6 g (0.2 mol) of 4,4'-diaminodiphenyl methane were dissolved in 70 mL and 30 mL of methanol, respectively. Then they were added to a three-necked flask equipped with an electric stirrer, a pure nitrogen protection device inlet, and a reflux condenser device, and the reaction was carried out in a 70 ℃ water bath. After 6 h of reaction, the obtained product was filtered to obtain yellow crystals, which were washed with methanol three times and dried to obtain the final product, a vanillyl dihydric phenol compound.

[0045] Step two: 34.95 g (0.075 mol) of the vanillyl dihydric phenol compound and 26.0 g (0.1 mol) of glycerol triacrylate were dissolved in 100 mL of DMF and added to a 250 mL three-necked flask equipped with a stirring device, and the reaction was carried out in an oil bath at 90-120 ℃ for 5 h to obtain a preliminary prepolymer.

[0046] Step three: 16.6 g (0.075 mol) of 3-aminopropyl triethoxysiloxane was added to the preliminary prepolymer, and the temperature was raised to 130 ℃ for 1 h. KOH was added, and the solution was stirred manually until it became viscous or bubbles appeared. The reaction was stopped, and the reaction mixture was quickly poured into a polytetrafluoroethylene (PTFE) mold for solidification.

[0047] Step four: The reaction mixture was pre-solidified at 50 ℃ for 2 h, solidified at 80 ℃ for 3 h, and post-solidified at 120 ℃ for 1 h to obtain a final bio-based epoxy glass high molecular film.

[0048] Example four:

[0049] As shown in Figure 2 Step one: 60.8 g (0.4 mol) of vanillin and 21.6 g (0.2 mol) of p-phenylenediamine were dissolved in 70 mL and 30 mL of methanol, respectively. Then they were added to a three-necked flask equipped with an electric stirrer, a pure nitrogen protection device inlet, and a reflux condenser device, and the reaction was carried out in a 70 ℃ water bath. After 6 h of reaction, the obtained product was filtered to obtain yellow crystals, which were washed with methanol three times and dried to obtain the final product, a vanillyl dihydric phenol compound.

[0050] Step two: 11.28 g (0.03 mol) of vanillyl diphenol compound, 55.2 g (0.06 mol) of epichlorohydrin and 0.72 g (0.003 mol) of tetrabutylammonium bromide were added to a three-necked flask and reacted at 85 °C for 4 h. After that, the temperature was lowered to 50 °C, then NaOH solution 10.92 g (0.06 mol) was added to the flask and the reaction was continued for 3 h. After the reaction was completed, the excess epichlorohydrin was removed, the resulting residue was washed with deionized water and dried in a freeze dryer overnight to obtain a vanillyl epoxy compound.

[0051] Step three: 3-aminopropyl triethoxysilane was added to the vanillyl epoxy compound, the temperature was raised to 130 °C and reacted for 1 h, KOH was added, and manual stirring was performed. When the solution became viscous or bubbles came out, the reaction was stopped, and the reaction mixture was quickly poured into a polytetrafluoroethylene (PTFE) mold for solidification.

[0052] Step four: The reaction mixture was pre-cured at 50 °C for 2 h, cured at 80 °C for 3 h, and post-cured at 120 °C for 1 h, finally obtaining a bio-based epoxy glass high molecular film.

[0053] Example five:

[0054] As shown in Figure 2 Step one: 60.8 g (0.4 mol) of vanillin and 23.2 g (0.2 mol) of hexanediamine were dissolved in 70 mL and 30 mL of methanol, respectively. Then they were added to a three-necked flask equipped with an electric stirrer, a pure nitrogen protection device inlet, and a reflux condensation device, and reacted in a 70 °C water bath. After 6 h of reaction, the product was obtained by suction filtration, washed with methanol three times, and dried to obtain the final product, vanillyl diphenol compound.

[0055] Step two: 11.28 g (0.03 mol) of vanillyl diphenol compound, 55.2 g (0.06 mol) of epichlorohydrin and 0.72 g (0.003 mol) of tetrabutylammonium bromide were added to a three-necked flask and reacted at 85 °C for 4 h. After that, the temperature was lowered to 50 °C, then NaOH solution 10.92 g (0.06 mol) was added to the flask and the reaction was continued for 3 h. After the reaction was completed, the excess epichlorohydrin was removed, the resulting residue was washed with deionized water and dried in a freeze dryer overnight to obtain a vanillyl epoxy compound.

[0056] Step three: 3-aminopropyl triethoxysilane was added to the vanillyl epoxy compound, and the temperature was raised to 130 °C for 1 h. KOH was added, and the solution was stirred manually. When the solution became viscous or bubbles appeared, the reaction was stopped, and the reaction mixture was quickly poured into a polytetrafluoroethylene (PTFE) mold for solidification.

[0057] Step four: The reaction mixture was pre-cured at 50 °C for 2 h, cured at 80 °C for 3 h, and post-cured at 120 °C for 1 h, respectively, to finally obtain a bio-based epoxy glass high molecular thin film.

[0058] Example six:

[0059] As shown in Figure 2 Step one: 60.8 g (0.4 mol) of vanillin and 39.6 g (0.2 mol) of 4,4'-diaminodiphenyl methane were dissolved in 70 mL and 30 mL of methanol, respectively. Then they were added to a three-necked flask equipped with an electric stirrer, a pure nitrogen inlet, and a reflux condenser. The reaction was carried out in a 70 °C water bath. After 6 h of reaction, the obtained product was filtered and washed with methanol three times. After drying, the final product, vanillyl dihydric phenol compound, was obtained.

[0060] Step two: 13.98 g (0.03 mol) of vanillyl dihydric phenol compound, 55.2 g (0.06 mol) of epichlorohydrin, and 0.72 g (0.003 mol) of tetrabutylammonium bromide were added to a three-necked flask and reacted at 85 °C for 4 h. After that, the temperature was reduced to 50 °C, and then a NaOH solution of 10.92 g (0.06 mol) was added to the flask, and the reaction was continued for 3 h. After the reaction was completed, the excess epichlorohydrin was removed, and the obtained residue was washed with deionized water and dried in a freeze dryer overnight to obtain a vanillyl epoxy compound.

[0061] Step three: 3-aminopropyl triethoxysilane was added to the vanillyl epoxy compound, and the temperature was raised to 130 °C for 1 h. KOH was added, and the solution was stirred manually. When the solution became viscous or bubbles appeared, the reaction was stopped, and the reaction mixture was quickly poured into a polytetrafluoroethylene (PTFE) mold for solidification.

[0062] Step four: The reaction mixture was pre-cured at 50 °C for 2 h, cured at 80 °C for 3 h, and post-cured at 120 °C for 1 h, respectively, to finally obtain a bio-based epoxy glass high molecular thin film.

[0063] The above merely describes preferred embodiments of the present application, and is not intended to limit the present application in any form; any person skilled in the art can easily implement the present application according to the drawings and the above description; however, any person skilled in the art can make some changes, modifications and equivalent changes within the scope of the technical solutions of the present application, and the equivalent embodiments of the present application are still within the protection scope of the technical solutions of the present application.

Claims

1. A method for preparing a bio-based epoxy glass polymer material modified with siloxane, characterized in that, include: S1, a diamine compound and vanillin were dissolved in methanol and reacted in a water bath under a nitrogen atmosphere. After post-treatment of the product, a vanillyl diphenol compound was obtained. S2, a vanillyl diphenol compound and an epoxy compound are dissolved in N,N-dimethylformamide and reacted in an oil bath under a nitrogen atmosphere to obtain a preliminary prepolymer; S3, 3-aminopropyltriethoxysiloxane is added to the preliminary prepolymer for reaction, followed by the addition of KOH for reaction. The reaction mixture is then cured by gradient heating to prepare a bio-based epoxy glass polymer material. The molar ratio of diamine compounds to vanillin in S1 is 1:2, and the total amount of diamine compounds and vanillin added in S1 accounts for 20 wt%-60 wt% of methanol. The molar ratio of the active hydrogen in the vanillyl diphenol compound to the epoxy group in the epoxy compound in S2 is 1:1; In the prepolymer of S3, the molar ratio of the active H groups in the vanillyl epoxy compound to those in 3-aminopropyltriethoxysiloxane is 1:

1. The diamine compounds include one of hexamethylenediamine, p-phenylenediamine, and 4,4'-diaminodiphenylmethane; The epoxy compound is one of glycerol triglycidyl ether and epichlorohydrin.

2. The method for preparing a siloxane-modified bio-based epoxy glass polymer material according to claim 1, characterized in that, The reaction temperature in S1 is 70 ℃ and the reaction time is 6 h; the reaction temperature in S2 is 90-120 ℃ and the reaction time is 3-5 h; the reaction temperature in S3 is 120-130 ℃ and the reaction time is 1-2 h.

3. The method for preparing a siloxane-modified bio-based epoxy glass polymer material according to claim 1, characterized in that, The curing temperatures and times for the bio-based epoxy glass polymer materials obtained in S3 were 60℃ for 2 hours of pre-curing, 80℃ for 3 hours of curing, and 120℃ for 1 hour of post-curing.

4. The method for preparing a siloxane-modified bio-based epoxy glass polymer material according to claim 1, characterized in that, The post-processing in S1 involves filtration and washing of the obtained reaction product.

5. A bio-based epoxy glass polymer material modified with siloxane, prepared according to the preparation method of a bio-based epoxy glass polymer material modified with siloxane as described in any one of claims 1-4.

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