Modified oyster shell powder / plant oil-based epoxy resin composite material and preparation method thereof

Abstract

The invention provides a modified oyster shell powder / plant oil-based epoxy resin composite material and a preparation method thereof, and belongs to the technical field of epoxy resin. The stearic acid is used for modifying the oyster shell powder, and the modified oyster shell powder is used for synthesizing the plant oil-based epoxy resin material, so that the prepared modified oyster shell powder / plant oil-based epoxy resin composite material has good mechanical property and hydrophobicity, and the problems of low mechanical strength and poor toughness of the traditional plant oil-based epoxy resin are solved; the preparation method and process of the epoxy resin composite material are green, free of emission, high in sustainability and high in practical application value.

Description

Technical Field

[0001] The invention specifically relates to a modified oyster shell powder / vegetable oil-based epoxy resin composite material and a preparation method thereof, and belongs to the technical field of epoxy resins. Background Art

[0002] Epoxy resin is the largest variety of thermosetting resins. It has excellent physical and mechanical properties, good heat resistance, electrical insulation and chemical stability, and has been widely used in the preparation of coatings, molded materials or injection molding materials. However, traditional epoxy resins are mainly prepared by ring-opening polymerization of bisphenol A-diglycidyl ether and organic polyamines. Its corresponding cross-linked chemical structure is very stable, and there are problems such as poor degradation and difficult recycling (recycling rate <10%). The treatment of its waste products is prone to cause serious waste of resources and environmental pollution. In addition, the preparation materials of traditional epoxy resins are mainly derived from petrochemical products. In the current context of the increasing depletion of global fossil resources and the increasingly serious energy crisis, the preparation and application of epoxy resins are not so "green and environmentally friendly".

[0003] At present, the preparation of epoxy resins using vegetable oils derived from natural substances as raw materials has become an important high-value and green preparation method for epoxy resins. Vegetable oils contain unsaturated bonds, which can be converted into epoxidized vegetable oils by grafting epoxy groups or epoxidation reactions, and then undergo curing reactions with organic amines, organic polyacids, polyphenols and polyols to obtain bio-based vegetable oil-based epoxy resins, which have the advantages of good biodegradability and green environmental protection; Chinese patent CN110903463A discloses a vegetable oil-based reprocessable thermosetting shape memory epoxy resin; the epoxy resin is made of vegetable oil-based epoxy polymers, anhydrides or carboxylic acids as raw materials, through the ring-opening reaction of epoxy groups on the fatty chain with anhydrides or carboxylic acids, and is prepared by heat curing process without adding catalysts; it has good molding processability, can be edited in shape, and can be processed multiple times, and has a wide range of application potential in structural and functional integrated materials.

[0004] It can be seen that plant oil-based epoxy resin, as a new type of bio-based epoxy resin, has shown a certain potential to replace traditional petroleum-based bisphenol A-diglycidyl ether epoxy resin, but its practical application still faces many problems; this is because there are hydrophobic fatty long carbon chains in the molecular structure of vegetable oil, and the cross-linking degree of existing plant oil-based epoxy resins is low, which leads to obvious deficiencies in the glass transition temperature, mechanical strength and thermal stability of plant oil-based epoxy resins; at the same time, affected by the longer hydrophobic fatty long carbon chain, traditional inorganic nanoparticles are also poorly compatible with the plant oil-based epoxy resin matrix, which limits the application of traditional inorganic nanoparticles to enhance and toughen epoxy resin modification methods; therefore, restricted by the chemical structure of vegetable oil itself, existing plant oil-based epoxy resins have obvious problems of low mechanical strength and poor toughness, which hinders the promotion and application of plant oil-based epoxy resins. Summary of the invention

[0005] In order to solve the problems in the prior art, the present invention provides a modified oyster shell powder / vegetable oil-based epoxy resin composite material and a preparation method thereof; the present invention uses stearic acid-modified oyster shell powder and uses the modified oyster shell powder for the synthesis of a vegetable oil-based epoxy resin material, and the prepared modified oyster shell powder / vegetable oil-based epoxy resin composite material has good mechanical properties and hydrophobicity, solves the problems of low mechanical strength and poor toughness of traditional vegetable oil-based epoxy resins, and the preparation process of the epoxy resin composite material is environmentally friendly and green, and has good economic benefits.

[0006] The technical solution of the present invention is as follows:

[0007] The invention provides a modified oyster shell powder / vegetable oil-based epoxy resin composite material, comprising the following components: modified oyster shell powder, epoxy vegetable oil, phthalic anhydride, zinc acetate and glycerol; in the modified oyster shell powder / vegetable oil-based epoxy resin composite material, the mass percentage of the modified oyster shell powder is 1-20%; the modified oyster shell powder is composed of stearic acid and oyster shell powder mixed evenly.

[0008] Furthermore, the epoxidized vegetable oil is one or a mixture of epoxidized castor oil, epoxidized soybean oil, epoxidized palm oil, and epoxidized rapeseed oil.

[0009] Furthermore, in the modified oyster shell powder, the mass of stearic acid is 0.5 to 20% of the mass of the oyster shell powder.

[0010] The present invention also provides a method for preparing the modified oyster shell powder / vegetable oil-based epoxy resin composite material, comprising the following steps:

[0011] S1, crushing, cleaning, drying and sieving oyster shells to obtain oyster shell powder;

[0012] S2, mixing stearic acid and oyster shell powder by ball milling to obtain modified oyster shell powder;

[0013] S3, dispersing the modified oyster shell powder in the epoxidized vegetable oil to obtain a suspended oily mixture;

[0014] S4, mixing phthalic anhydride, glycerol and zinc acetate, and placing the obtained mixed solution at 80-120° C. and stirring for 10-60 minutes to obtain a phthalic anhydride-glycerol eutectic solution, and then adding the suspended oily mixture obtained in step S3 thereto, stirring and mixing well to obtain a prepolymer mixture;

[0015] S5. After the prepolymerized mixture is allowed to stand and solidify, the modified oyster shell powder / vegetable oil-based epoxy resin composite material is obtained.

[0016] Furthermore, the sieve in step S1 is 100 mesh, and the particle size of the oyster shell powder obtained in step S1 is less than 150 microns.

[0017] Furthermore, the amount of stearic acid used in step S2 is 0.5-20% of the mass of the oyster shell powder.

[0018] Furthermore, the temperature for static curing in step S5 is 120°C.

[0019] Different from the prior art, the present invention has the following beneficial effects:

[0020] 1. The present invention uses stearic acid to modify oyster shell powder. The carboxyl functional groups of stearic acid on the surface of oyster shell powder particles can be in situ chelated with the calcium carbonate component in the oyster shell powder, which effectively improves the hydrophobicity of the oyster shell powder surface and its compatibility with the epoxy resin matrix, reduces the surface energy of the oyster shell powder, and makes the modified oyster shell powder have good dispersibility and interfacial force in the epoxy resin system.

[0021] 2. The present invention applies the modified oyster shell powder to the synthesis of plant oil-based epoxy resin materials. The porous structure of the evenly dispersed modified oyster shell powder can form a strong mechanical interlocking effect with the plant oil-based epoxy resin matrix, thereby improving the tensile and impact resistance of the matrix. At the same time, the even dispersion of the oyster shell powder in the resin matrix also avoids its local curing concentration being too high or too low, effectively promoting the curing activity of the epoxy resin composite material, and making the curing reaction faster and more sufficient. In addition, the carboxylic acid group contained in the stearic acid of the modified oyster shell powder can also react with the epoxy group, thereby introducing more cross-linking points into the plant oil-based epoxy resin and increasing the cross-linking density, thereby solving the problem of few cross-linking points and poor cross-linking reaction activity of the traditional plant oil-based epoxy resin. The above characteristics enable the modified oyster shell powder / plant oil-based epoxy resin composite material of the present invention to overcome the problems of low mechanical strength and poor toughness of the traditional plant oil-based epoxy resin, and has better toughness and hydrophobicity.

[0022] 3. The preparation process of the modified oyster shell powder / vegetable oil-based epoxy resin composite material provided by the present invention uses the low-cost, green and environmentally friendly oyster shell as filler. The material source is wide and common, and the recycling of waste marine biomass resources is realized; in addition, the preparation process can also use epoxidized castor oil, epoxidized soybean oil, epoxidized palm oil, epoxidized rapeseed oil and other vegetable oils as raw materials for epoxy resin synthesis, which can meet the preparation of a variety of vegetable oil-based epoxy resins, has good economy, practicality and operability, and is in line with the concept of sustainable development, and has broad promotion and application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is the SEM image of the stearic acid modified oyster shell powder of Example 1.

[0024] Figure 2 This is the tensile spline diagram of the modified oyster shell powder / bio-based epoxy resin composite material obtained in Example 1.

[0025] Figure 3 This is the surface SEM image of the modified oyster shell powder / bio-based epoxy resin composite material obtained in Example 1. DETAILED DESCRIPTION

[0026] The present invention will be further described below in conjunction with the accompanying drawings and preferred embodiments. The given embodiments are only for illustrating the present invention, rather than for limiting the scope of the present invention.

[0027] Unless otherwise specified, the materials, reagents, etc. used in the following examples can be obtained from commercial sources; the methods in the following examples are conventional methods unless otherwise specified.

[0028] Example 1

[0029] This embodiment provides a modified oyster shell powder / vegetable oil-based epoxy resin composite material, comprising the following components:

[0030] Modified oyster shell powder, epoxidized vegetable oil, phthalic anhydride, zinc acetate and glycerol; by mass, 122.2 parts of epoxidized soybean oil, 59.2 parts of phthalic anhydride, 0.34 parts of zinc acetate, 18.4 parts of glycerol, and 10 parts of modified oyster shell powder; the epoxidized vegetable oil can be a mixture of one or more of epoxidized castor oil, epoxidized soybean oil, epoxidized palm oil, and epoxidized rapeseed oil, and epoxidized soybean oil is used in this embodiment; the modified oyster shell powder is composed of a mixture of stearic acid and oyster shell powder, wherein the mass of stearic acid can be 0.5-20% of the mass of oyster shell, and the amount of stearic acid added in this embodiment is 5% of the amount of oyster shell added.

[0031] The preparation method of the modified oyster shell powder / vegetable oil-based epoxy resin composite material provided in this embodiment is as follows:

[0032] S1, crushing, cleaning, drying and sieving the oyster shells through a 100-mesh sieve to obtain oyster shell powder with a particle size of less than 150 microns;

[0033] S2, put 10 parts of stearic acid and 200 parts of oyster shell powder into a ball mill, high-speed ball mill at a speed of 500r / min for 45min, seal and dry for storage, to obtain modified oyster shell powder; the SEM image of the modified oyster shell powder is as follows Figure 1 As shown;

[0034] S3, weighing 10.0 parts of modified oyster shell powder and dispersing it in 122.2 parts of epoxidized soybean oil, stirring and mixing continuously and ultrasonically treating at room temperature for 15 minutes to obtain a suspended oily mixture;

[0035] S4, weighing 59.2 parts of phthalic anhydride, 0.34 parts of zinc acetate and 18.4 parts of glycerol, adding them into a stirred reactor, stirring at 300 rpm at 120° C. for 30 min, then lowering the temperature to 70° C., adding the suspended oily mixture obtained in step S4, stirring at 500 rpm for 5 min, to obtain a prepolymer mixture;

[0036] S5. Add the prepolymer mixture into a polytetrafluoroethylene mold, put it into a 120° C. oven for curing for 3 hours to obtain the modified oyster shell powder / vegetable oil-based epoxy resin composite material.

[0037] The tensile spline graph and surface SEM image of the modified oyster shell powder / vegetable oil-based epoxy resin composite material prepared in this embodiment are shown in FIG. Figures 2-3 shown.

[0038] Example 2

[0039] This embodiment provides a modified oyster shell powder / vegetable oil-based epoxy resin composite material, which is different from Embodiment 1 in that the amount of stearic acid added in this embodiment is 10% of the amount of oyster shell added, and the rest remains unchanged.

[0040] The difference between the preparation method of the modified oyster shell powder / vegetable oil-based epoxy resin composite material provided in this embodiment and that in Example 1 is that the amount of stearic acid used in step S2 is 20 parts, and the others remain unchanged.

[0041] Example 3

[0042] The present embodiment provides a modified oyster shell powder / vegetable oil-based epoxy resin composite material, comprising the following components: modified oyster shell powder, epoxy vegetable oil, phthalic anhydride, zinc acetate and glycerol; the difference from Example 1 is that: in terms of mass fractions, the mass fraction of the modified oyster shell powder is 20 parts, and the others remain unchanged.

[0043] The preparation method of the modified oyster shell powder / vegetable oil-based epoxy resin composite material provided in this embodiment is different from that in Example 1 in that the amount of modified oyster shell powder used in step S3 is 20.0 parts, and the others remain unchanged.

[0044] Example 4

[0045] The present embodiment provides a modified oyster shell powder / vegetable oil-based epoxy resin composite material, comprising the following components: modified oyster shell powder, epoxy vegetable oil, phthalic anhydride, zinc acetate and glycerol; the difference from Example 1 is that the mass fraction of the modified oyster shell powder is 30 parts by mass, and the others remain unchanged.

[0046] The difference between the preparation method of the modified oyster shell powder / vegetable oil-based epoxy resin composite material provided in this embodiment and that in Example 1 is that the amount of modified oyster shell powder used in step S3 is 30.0 parts, and the others remain unchanged.

[0047] Example 5

[0048] The present embodiment provides a modified oyster shell powder / vegetable oil-based epoxy resin composite material, comprising the following components: modified oyster shell powder, epoxidized vegetable oil, phthalic anhydride, zinc acetate and glycerol; in terms of mass fractions, epoxidized castor oil is 122.2 parts, phthalic anhydride is 59.2 parts, zinc acetate is 0.34 parts, glycerol is 18.4 parts, and modified oyster shell powder is 50 parts; the epoxidized vegetable oil used in the present embodiment is epoxidized castor oil; the preparation method of the modified oyster shell powder is as described in Example 1, and the amount of stearic acid added in the present embodiment is 0.5% of the amount of oyster shell added.

[0049] The preparation method of the modified oyster shell powder / vegetable oil-based epoxy resin composite material provided in this embodiment comprises the following steps:

[0050] S1, crushing, washing, drying and sieving oyster shells through a 100-mesh sieve to obtain oyster shell powder;

[0051] S2, putting 1 part of stearic acid and 200 parts of oyster shell powder into a ball mill, high-speed ball milling at a speed of 500 r / min for 45 min, sealing and dry storage, to obtain modified oyster shell powder;

[0052] S3, dispersing 50 parts of modified oyster shell powder in 122.2 parts of epoxidized vegetable oil to obtain a suspended oily mixture;

[0053] S4, weighing 59.2 parts of phthalic anhydride, 0.34 parts of zinc acetate and 18.4 parts of glycerol, adding them into a stirred reactor, stirring and reacting at 80° C. for 10 minutes to obtain a phthalic anhydride-glycerol eutectic solution, then adding the suspended oily mixture obtained in step S3 thereto, stirring at 500 rpm for 5 minutes to obtain a prepolymer mixture;

[0054] S5. Add the prepolymer mixture into a polytetrafluoroethylene mold, put it into a 120° C. oven for curing for 3 hours to obtain the modified oyster shell powder / vegetable oil-based epoxy resin composite material.

[0055] Example 6

[0056] This embodiment provides a modified oyster shell powder / vegetable oil-based epoxy resin composite material, comprising the following components:

[0057] Modified oyster shell powder, epoxidized vegetable oil, phthalic anhydride, zinc acetate and glycerol; by weight, 122.2 parts of epoxidized castor oil, 59.2 parts of phthalic anhydride, 0.34 parts of zinc acetate, 18.4 parts of glycerol, and 2 parts of modified oyster shell powder; the epoxidized vegetable oil used in this embodiment is epoxidized palm oil; the preparation method of the modified oyster shell powder is as described in Example 1, and the amount of stearic acid added in this embodiment is 20% of the amount of oyster shell added.

[0058] The preparation method of the modified oyster shell powder / vegetable oil-based epoxy resin composite material provided in this embodiment comprises the following steps:

[0059] S1, crushing, washing, drying and sieving oyster shells through a 100-mesh sieve to obtain oyster shell powder;

[0060] S2, put 40 parts of stearic acid and 200 parts of oyster shell powder into a ball mill, high-speed ball mill at a speed of 500r / min for 45min, seal and dry and store to obtain modified oyster shell powder;

[0061] S3, dispersing 2 parts of modified oyster shell powder in 122.2 parts of epoxidized vegetable oil to obtain a suspended oily mixture;

[0062] S4, weighing 59.2 parts of phthalic anhydride, 0.34 parts of zinc acetate and 18.4 parts of glycerol, adding them into a stirred reactor, stirring and reacting at 120° C. for 60 minutes to obtain a phthalic anhydride-glycerol eutectic solution, then adding the suspended oily mixture obtained in step S3 thereto, stirring at 500 rpm for 5 minutes to obtain a prepolymer mixture;

[0063] S5. Add the prepolymer mixture into a polytetrafluoroethylene mold, put it into a 120° C. oven for curing for 3 hours to obtain the modified oyster shell powder / vegetable oil-based epoxy resin composite material.

[0064] Comparative Example 1

[0065] This comparative example provides a method for preparing an oyster shell powder / vegetable oil-based epoxy resin composite material, which is different from Example 1 in that: in step S1, the amount of stearic acid used is 0 part, and the others remain unchanged.

[0066] Comparative Example 2

[0067] This comparative example provides a vegetable oil-based epoxy resin, which is different from Example 1 in that: the components of the vegetable oil-based epoxy resin do not contain modified oyster shell powder, and include the following components: epoxidized vegetable oil, phthalic anhydride, zinc acetate and glycerol; the epoxidized vegetable oil is epoxidized soybean oil; in parts by mass, the epoxidized soybean oil is 122.2 parts, the phthalic anhydride is 59.2 parts, the zinc acetate is 0.34 parts, and the glycerol is 18.4 parts.

[0068] The preparation method of the vegetable oil-based epoxy resin provided in this comparative example comprises the following steps:

[0069] Weigh 59.2 parts of phthalic anhydride, 0.34 parts of zinc acetate and 18.4 parts of glycerol, add to a stirred reactor, stir and react at 120°C at 300 rpm for 30 minutes, reduce the temperature to 70°C, add 122.2 parts of epoxidized soybean oil, transfer to a polytetrafluoroethylene mold, and place in a 120°C oven for curing for 3 hours.

[0070] Performance Testing

[0071] The modified oyster shell powder / vegetable oil-based epoxy resin composite material obtained in Examples 1 to 4 was selected for mechanical property testing, and the results are shown in Table 1. The results show that the comprehensive properties of the epoxy resin composite material can be simply regulated by changing the amount of stearic acid added or the amount of modified oyster shell powder filled.

[0072] Comparing Examples 1 to 4 with Comparative Examples 1 to 2, the results show that the tensile strength of Examples 1 to 4 is significantly improved, and the elongation at break is reduced; the oyster shell powder modified with stearic acid can effectively improve the mechanical properties of the vegetable oil-based epoxy resin material.

[0073] Table 1 Mechanical properties test results of the plant oil-based epoxy resin materials and their composite materials obtained in each embodiment

[0074]

[0075]

Claims

1. A modified oyster shell powder / vegetable oil-based epoxy resin composite material, characterized in that: The modified oyster shell powder / vegetable oil-based epoxy resin composite material comprises the following components: modified oyster shell powder, epoxy vegetable oil, phthalic anhydride, zinc acetate and glycerol; In the modified oyster shell powder / vegetable oil-based epoxy resin composite material, the mass percentage of the modified oyster shell powder is 1-20%; the modified oyster shell powder is composed of a uniform mixture of stearic acid and oyster shell powder.

2. The modified oyster shell powder / vegetable oil-based epoxy resin composite material according to claim 1, characterized in that: The epoxidized vegetable oil is one or a mixture of epoxidized castor oil, epoxidized soybean oil, epoxidized palm oil and epoxidized rapeseed oil.

3. The modified oyster shell powder / vegetable oil-based epoxy resin composite material according to claim 1, characterized in that: In the modified oyster shell powder, the mass of stearic acid is 0.5-20% of the mass of the oyster shell powder.

4. A method for preparing the modified oyster shell powder / vegetable oil-based epoxy resin composite material according to any one of claims 1 to 3, characterized in that: The steps include: S1, crushing, cleaning, drying and sieving oyster shells to obtain oyster shell powder; S2, mixing stearic acid and oyster shell powder by ball milling to obtain modified oyster shell powder; S3, dispersing the modified oyster shell powder in the epoxidized vegetable oil to obtain a suspended oily mixture; S4, mixing phthalic anhydride, glycerol and zinc acetate, and placing the obtained mixed solution at 80-120° C. and stirring for 10-60 minutes to obtain a phthalic anhydride-glycerol eutectic solution, and then adding the suspended oily mixture obtained in step S3 thereto, stirring and mixing well to obtain a prepolymer mixture; S5. After the prepolymerized mixture is allowed to stand and solidify, the modified oyster shell powder / vegetable oil-based epoxy resin composite material is obtained.

5. The method for preparing the modified oyster shell powder / vegetable oil-based epoxy resin composite material according to claim 4, characterized in that: The sieve in step S1 is 100 mesh, and the particle size of the oyster shell powder obtained in step S1 is less than 150 microns.

6. The modified oyster shell powder / vegetable oil-based epoxy resin composite material according to claim 3, characterized in that: The temperature for curing in step S5 is 120°C.

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