A synthesis process and application of a bio-based degradable polyester resin

Abstract

The present invention discloses a synthesis process and application of a bio-based degradable polyester resin, and the present invention relates to the technical field of polyester resins. The synthesis process and application of the bio-based degradable polyester resin, through the modification treatment of carbon fibers, enable a thiol polymer to form a coating on the surface of the carbon fibers, improve the interfacial compatibility between the carbon fibers and the polyester resin, and make the combination between the carbon fibers and the resin matrix closer; the modification treatment can reduce the mutual attraction between the carbon fibers, make them uniformly dispersed in the resin matrix, prevent the agglomeration of the carbon fibers, and further make the performance of the composite material more uniform, improving the tensile strength, bending strength, impact resistance, etc. of the resin; moreover, the thiol polymer coating and the degradation process of the polyester resin produce a synergistic effect, guiding or promoting the degradation of the polyester resin, so that the bio-based polyester resin can be better biodegradable after being discarded, reducing environmental pollution.

Description

Technical Field

[0001] The present invention relates to the technical field of polyester resins, and specifically to a synthesis process and application of a bio-based degradable polyester resin. Background Art

[0002] Chinese Patent with Publication No. CN106715525B discloses a bio-based hydroxyl or carboxyl polyester resin, which is characterized in that it is made from the following: a) an acid component, which includes: a1) at least one C4-C6 polycarboxylic acid or polycarboxylic anhydride, a2) at least one C8-C54 polycarboxylic acid or polycarboxylic anhydride, a3) optionally at least one C2-C22 saturated monocarboxylic acid, b) an alcohol component, which includes: b1) at least one bio-based polyol having a functionality of at least 2, and at least one of the following two polyols b2) or b3): b2) at least one polyol different from b1) having a functionality of at least 2, b3) at least one polyol different from b1) and b2) having a functionality of at least 3. The resin is more particularly 100% bio-based. The invention also relates to a resin solution and a coating composition comprising the resin and its use in a coating having high strength and made from renewable raw materials. However, the degradation performance of the polyester resin prepared by the above prior art during use needs to be improved; for this reason, the present invention provides a synthesis process and application of a bio-based degradable polyester resin to solve the above problems. Summary of the Invention

[0003] (I) Technical Problems to be Solved

[0004] In view of the deficiencies of the prior art, the present invention provides a synthesis process and application of a bio-based degradable polyester resin, which solves the problem of poor degradation performance of the above polyurethane resin.

[0005] (II) Technical Solutions

[0006] To achieve the above object, the present invention is realized through the following technical solutions: A synthesis process of a bio-based degradable polyester resin includes the following synthesis steps:

[0007] Step 1: Mix 1.4 - 2 g of succinic acid with 1 - 1.6 g of propylene glycol, and successively add 0.12 - 0.2 g of a catalyst and 0.12 - 0.18 g of an inhibitor. Under a nitrogen atmosphere, heat up to 145 - 160 °C and react for 1.5 - 2 h;

[0008] Step 2: Evacuate to a vacuum degree of 0.07 - 0.09 MPa and continue to react for 4.5 - 5 h at a temperature of 140 - 160 °C;

[0009] Step 3: Place it in 12.5 - 20 g of deionized water, cool down to 80 - 90 °C, stir for 25 - 35 min, then let it stand. After pouring off the supernatant, evacuate to a vacuum degree of 0.07 - 0.09 MPa, heat up to 110 - 125 °C, react for 2.5 - 3 h, and then cool down to room temperature;

[0010] Step 4: Pour it into 1.5 - 2 g of diluent, stir evenly, add 0.1 - 0.25 g of initiator and 0.02 - 0.04 g of accelerator, and stir evenly;

[0011] Step 5: Add 2.2 - 2.8 g of modified carbon fiber and 0.4 - 0.8 g of composite filler, mix evenly, and then synthesize the bio - based degradable polyester resin.

[0012] Preferably, in the above Step 1, the catalyst is tetrabutyl titanate and the inhibitor is hydroquinone.

[0013] Preferably, in the above Step 4, the diluent is dimethyl itaconate, the initiator is cyclohexanone peroxide, and the accelerator is cobalt naphthenate.

[0014] Preferably, the preparation method of the modified carbon fiber is as follows:

[0015] (1) Immerse 8 - 15 g of carbon fiber in 25 - 45 mL of mixed solution;

[0016] (2) Put it into an ultraviolet reactor with 460 - 500 W, and react for 30 - 40 min;

[0017] (3) Wash it with chloroform for 2 - 4 times, and then dry it in an oven at 50 - 60 °C for 45 - 60 min to obtain the modified carbon fiber.

[0018] Preferably, in the above (1), the mixed solution is a mixed solution of thiol polymer, chloroform and α,α - dimethoxy - α - acetophenone, and its volume ratio is (0.2 - 0.6):0.5:(0.8 - 2).

[0019] Preferably, the preparation method of the thiol polymer is: Mix 1 - 3 g of bismaleimide, 0.8 - 2 g of trimethylolpropane tris(3 - mercaptopropionate) and 0.9 - 3 g of triethylamine, then add 15 - 25 mL of dichloromethane, stir and heat up to 45 - 60 °C, and react for 3.5 - 4 h under a nitrogen atmosphere to obtain the thiol polymer.

[0020] Preferably, the preparation method of the composite filler is as follows:

[0021] S1: Mix 30 - 36 mL of isopropanol and 10 - 20 mL of N,N - dimethylformamide and stir for 10 - 20 min;

[0022] S2. Add 0.4 - 0.9 g of tetrabutyl titanate, continue to mix and stir for 10 - 15 min, then pour the mixed solution into a sealed container, heat it up to 200 - 220 °C, and react for 20 - 24 h;

[0023] S3. Take it out and cool it to room temperature, wash it 3 - 5 times with absolute ethanol, centrifuge it at a speed of 2500 - 3500 r / mi for 8 - 10 min, and then wash it 3 - 5 times with deionized water;

[0024] S4. First, dry it in a blast drying oven at 55 - 60 °C for 10 - 12 h, then place it in a muffle furnace, heat it up to 420 - 450 °C, and calcine it for 2 h;

[0025] S5. Pour it into 65 - 80 mL of H2PtCl6·6H20 solution with a concentration of 4 g / L, stir and react for 22 - 24 h, and then irradiate it under a xenon lamp;

[0026] S6. Centrifuge it at a speed of 5000 - 7000 r / min for 10 - 13 min, wash it 2 - 4 times with deionized water, and then dry it in a drying oven at 50 - 60 °C for 22 - 24 h to obtain the composite filler.

[0027] Preferably, in S4, the heating rate is 5 - 7 °C / min.

[0028] Preferably, in S5, the xenon lamp is equipped with a filter with a wavelength of 400 - 420 nm, the irradiation intensity is 280 - 300 W, and the irradiation time is 50 - 60 min.

[0029] Application of a bio - based biodegradable polyester resin in packaging materials.

[0030] (III) Beneficial effects

[0031] The present invention provides a synthesis process and application of a bio - based biodegradable polyester resin. Compared with the prior art, it has the following beneficial effects:

[0032] (1). In the synthesis process and application of the bio - based biodegradable polyester resin, by modifying the carbon fiber, a layer of coating of mercapto polymer is formed on the surface of the carbon fiber, improving the interfacial compatibility between the carbon fiber and the polyester resin, making the combination between the carbon fiber and the resin matrix closer; the modification treatment can reduce the mutual attraction between carbon fibers, making them uniformly dispersed in the resin matrix, preventing the agglomeration of carbon fibers, and thus making the properties of the composite material more uniform, improving the tensile strength, flexural strength, impact resistance, etc. of the resin; moreover, the mercapto polymer coating and the degradation process of the polyester resin produce a synergistic effect, guiding or promoting the degradation of the polyester resin, so that the bio - based polyester resin can be better biodegraded after being discarded, reducing environmental pollution.

[0033] (2) The synthesis process and application of the bio-based degradable polyester resin. The composite filler absorbs light energy and generates free radicals, which trigger the breakage of the polyester resin molecular chains, accelerating the photodegradation process, facilitating the decomposition of the polyester resin in the natural environment, and reducing white pollution. At the same time, the addition of the composite filler can change the surface properties of the polyester resin, making it easier to be attached and decomposed by microorganisms, improving the degradation performance of the polyester resin. Moreover, the composite filler interacts with the polyester resin molecular chains to form chemical bonds or physical cross-linking points, enhancing the binding force between the molecular chains, thereby improving the mechanical properties of the polyester resin. Description of the Drawings

[0034] Figure 1 SEM images of the carbon fiber before and after modification provided by the present invention;

[0035] Figure 2 Comparison chart of the degradation performance test of the bio-based degradable polyester resin provided by the present invention. Detailed Embodiments

[0036] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0037] In this application, the carbon fiber is a polyacrylonitrile-based carbon fiber, purchased from Chengdu Luchen New Materials Technology Co., Ltd.

[0038] Example 1

[0039] A synthesis process of a bio-based degradable polyester resin includes the following synthesis steps:

[0040] Step 1: Mix 1.4 g of succinic acid with 1 g of propylene glycol, and sequentially add 0.12 g of tetrabutyl titanate and 0.12 g of hydroquinone. Under a nitrogen atmosphere, heat to 145 °C and react for 1.5 h;

[0041] Step 2: Evacuate to a vacuum degree of 0.07 MPa and continue to react for 4.5 h at a temperature of 140 °C;

[0042] Step 3: Place it in 12.5 g of deionized water, cool to 80 °C, stir for 25 min, then let it stand. After pouring off the supernatant, evacuate to a vacuum degree of 0.07 MPa, heat to 110 °C, react for 2.5 h, and then cool to room temperature;

[0043] Step 4: Pour 1.5 g of dimethyl itaconate, stir evenly, then add 0.1 g of cyclohexanone peroxide and 0.02 g of cobalt naphthenate, and stir evenly;

[0044] Step 5: Add 2.2 g of modified carbon fiber and 0.4 g of composite filler, mix evenly, and then synthesize the bio-based biodegradable polyester resin;

[0045] Among them, the preparation method of the modified carbon fiber:

[0046] (1) Mix 1 g of bismaleimide, 0.8 g of trimethylolpropane tris(3-mercaptopropionate) and 0.9 g of triethylamine, add 15 mL of dichloromethane, stir and heat up to 45 °C, and react for 3.5 h under a nitrogen atmosphere to obtain a mercapto polymer;

[0047] (2) Immerse 8 g of carbon fiber in a mixed solution of 25 mL of mercapto polymer, chloroform and α,α-dimethoxy-α-phenylethyl ketone with a volume ratio of 0.2:0.5:0.8; put it into a 460 W ultraviolet reactor and react for 30 min; wash it twice with chloroform, then place it in a drying oven at 50 °C and dry for 45 min to obtain the modified carbon fiber;

[0048] The preparation method of the composite filler is as follows: Mix 30 mL of isopropanol and 10 mL of N,N-dimethylformamide and stir for 10 min; add 0.4 g of tetrabutyl titanate, continue to mix and stir for 10 min, then pour the mixed solution into a sealed container, heat up to 200 °C, and react for 20 h; take it out and cool to room temperature, wash it three times with absolute ethanol, then centrifuge at a speed of 2500 r / mi for 8 min, and then wash it three times with deionized water; first dry it in a blast drying oven at 55 °C for 10, then place it in a muffle furnace, heat it up to 420 °C at a heating rate of 5 °C / min, and calcine for 2 h; pour it into 65 mL of H2PtCl6·6H20 solution with a concentration of 4 g / L, stir and react for 22 h, then place it under a xenon lamp equipped with a 400 nm filter for irradiation, the irradiation intensity is 280 W, and the irradiation time is 50 min; centrifuge at a speed of 5000 r / min for 10 min, then wash it twice with deionized water, and then place it in a drying oven at 50 °C and dry for 22 h to obtain the composite filler.

[0049] Example 2

[0050] A synthesis process of bio-based biodegradable polyester resin, including the following synthesis steps:

[0051] Step 1: Mix 1.7 g of succinic acid and 1.3 g of propylene glycol, add 0.16 g of tetrabutyl titanate and 0.15 g of hydroquinone in sequence, under a nitrogen atmosphere, heat up to 150 °C, and react for 1.8 h;

[0052] Step 2: Evacuate to a vacuum degree of 0.08 MPa and continue the reaction for 4.8 h under the temperature condition of 150 °C;

[0053] Step 3: Place it in 17.5 g of deionized water, cool down to 85 °C, stir for 30 min, then let it stand. After pouring off the supernatant, evacuate to a vacuum degree of 0.08 MPa, heat up to 115 °C, react for 2.8 h, and then cool down to room temperature;

[0054] Step 4: Pour it into 1.7 g of dimethyl itaconate, stir evenly, add 0.2 g of cyclohexanone peroxide and 0.03 g of cobalt naphthenate, and stir evenly;

[0055] Step 5: Add 2.5 g of modified carbon fiber and 0.6 g of composite filler, mix evenly, and then synthesize the bio-based biodegradable polyester resin;

[0056] Among them, the preparation method of the modified carbon fiber:

[0057] (1) After mixing 2 g of bismaleimide, 1.9 g of trimethylolpropane tris(3-mercaptopropionate) and 1.9 g of triethylamine, add 20 mL of dichloromethane, stir and heat up to 50 °C, and react for 3.7 h under a nitrogen atmosphere to obtain a mercapto polymer;

[0058] (2) Immerse 12 g of carbon fiber in a mixed solution of 35 mL of mercapto polymer, chloroform and α,α-dimethoxy-α-phenylethyl ketone with a volume ratio of 0.4:0.5:1.4; put it into a 480 W ultraviolet reactor and react for 35 min; wash it 3 times with chloroform, and then dry it in a drying oven at 55 °C for 50 min to obtain the modified carbon fiber;

[0059] The preparation method of the composite filler is as follows: Mix 33 mL of isopropanol and 15 mL of N,N-dimethylformamide and stir for 15 min; add 0.6 g of tetrabutyl titanate, continue to mix and stir for 12 min, then pour the mixed solution into a sealed container, heat up to 210 °C, and react for 22 h; take it out and cool down to room temperature, wash it 4 times with absolute ethanol, then centrifuge at a speed of 3000 r / min for 9 min, and then wash it 4 times with deionized water; first dry it in a forced-air drying oven at 58 °C for 11 h, then place it in a muffle furnace, heat it up to 440 °C at a heating rate of 6 °C / min, and calcine for 2 h; pour it into 70 mL of an H2PtCl6·6H20 solution with a concentration of 4 g / L, stir and react for 23 h, then place it under a xenon lamp equipped with a 410 nm filter for irradiation, the irradiation intensity is 290 W, and the irradiation time is 55 min; centrifuge at a speed of 6000 r / min for 12 min, then wash it 3 times with deionized water, and then dry it in a drying oven at 55 °C for 23 h to obtain the composite filler.

[0060] Example 3

[0061] A synthetic process for a bio-based degradable polyester resin, comprising the following synthetic steps:

[0062] Step 1: Mix 2 g of succinic acid with 1.6 g of propylene glycol, and sequentially add 0.2 g of tetrabutyl titanate and 0.18 g of hydroquinone. Under a nitrogen atmosphere, heat up to 160 °C and react for 2 h;

[0063] Step 2: Evacuate to a vacuum degree of 0.09 MPa and continue to react at a temperature of 160 °C for 5 h;

[0064] Step 3: Place it in 20 g of deionized water, cool down to 90 °C, stir for 35 min, then let it stand. After pouring off the supernatant, evacuate to a vacuum degree of 0.09 MPa, heat up to 125 °C, react for 3 h, and then cool to room temperature;

[0065] Step 4: Pour it into 2 g of dimethyl itaconate, stir evenly, add 0.25 g of cyclohexanone peroxide and 0.04 g of cobalt naphthenate, and stir evenly;

[0066] Step 5: Add 2.8 g of modified carbon fiber and 0.8 g of composite filler, mix evenly, and then synthesize the bio-based degradable polyester resin;

[0067] Among them, the preparation method of the modified carbon fiber:

[0068] (1) Mix 3 g of bismaleimide, 2 g of trimethylolpropane tris(3-mercaptopropionate) and 3 g of triethylamine, then add 25 mL of dichloromethane, stir and heat up to 60 °C, and react for 4 h under a nitrogen atmosphere to obtain a mercapto polymer;

[0069] (2) Immerse 15 g of carbon fiber in a mixed solution of 45 mL of mercapto polymer, chloroform and α,α-dimethoxy-α-phenylethanone with a volume ratio of 0.6:0.5:2; put it into a 500 W ultraviolet reactor and react for 40 min; wash it 4 times with chloroform, and then dry it in an oven at 60 °C for 60 min to obtain the modified carbon fiber;

[0070] The preparation method of the composite filler is as follows: Mix 36 mL of isopropanol and 20 mL of N,N-dimethylformamide and stir for 20 min; add 0.9 g of tetrabutyl titanate, continue to mix and stir for 15 min, then pour the mixed solution into a sealed container, heat up to 220 °C, and react for 24 h; take it out and cool to room temperature, wash it 5 times with absolute ethanol, centrifuge at a speed of 3500 r / mi for 10 min, and then wash it 5 times with deionized water; first dry it in a blast drying oven at 60 °C for 12 h, then place it in a muffle furnace, heat it up to 450 °C at a heating rate of 7 °C / min, and calcine for 2 h; pour it into 80 mL of H2PtCl6·6H20 solution with a concentration of 4 g / L, stir and react for 24 h, then place it under a xenon lamp equipped with a 420 nm filter for irradiation, the irradiation intensity is 300 W, and the irradiation time is 60 min; centrifuge at a speed of 7000 r / min for 13 min, wash it 4 times with deionized water, and then dry it in a drying oven at 60 °C for 24 h to obtain the composite filler.

[0071] Comparative Example 1

[0072] Compared with Example 1, the difference is that the modified carbon fiber in Example 1 is replaced with carbon fiber; the rest remains unchanged.

[0073] Comparative Example 2

[0074] Compared with Example 1, the difference is that the composite filler in Example 1 is not added; the rest remains unchanged.

[0075] Mechanical property test: Conduct the test on a universal material testing machine according to the ASTM D2344 standard, and the test temperature is 25 °C.

[0076] Tensile property: Conduct the test according to GB / T 3354-2014; the results are shown in Table 1.

[0077] Flexural property: Conduct the test according to GB / T 2567-2008; the results are shown in Table 1.

[0078]

[0079] Degradation property test: Make the polyester resin into a film with a size of 30 mm × 30 mm × 0.5 mm, wrap it with non-toxic plastic mesh gauze and bury it in the soil, bury it 25 cm deep underground, and measure its degradation degree every 2 weeks; as Figure 2 shown, compared with Comparative Examples 1-2, the specimens prepared in Examples 1-3 have a weight loss rate of nearly 10% at 30 weeks and have good degradation properties.

[0080] As Figure 1As shown, the surface of the carbon fiber before modification is smooth and neat; the surface of the modified carbon fiber becomes rough, with narrow grooves parallel to the longitudinal direction of the fiber on the surface, enabling the polymer particle layer to be dispersed on the fiber surface and in the grooves through adsorption, providing more contact points during the matrix compaction process, helping to increase the interaction between the matrix resin and the fiber. At the same time, the modified carbon fiber has a more closely packed structure, thus improving the mechanical properties of the carbon fiber.

[0081] Meanwhile, the content not described in detail in this specification belongs to the prior art well-known to those skilled in the art.

[0082] It should be noted that, in this text, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variation thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device.

[0083] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A bio-based degradable polyester resin synthesis process, characterized in that: The synthesis steps include: Step 1: Mix 1.4-2g of succinic acid and 1-1.6g of propylene glycol, add 0.12-0.2g of catalyst and 0.12-0.18g of inhibitor in sequence, raise the temperature to 145-160°C under nitrogen atmosphere, and react for 1.5-2h; Step 2: Evacuate to a vacuum degree of 0.07-0.09 MPa and continue the reaction at a temperature of 140-160°C for 4.5-5 hours; Step 3: Place in 12.5-20g of deionized water, cool to 80-90°C, stir for 25-35min, let stand, pour out the supernatant, evacuate to a vacuum degree of 0.07-0.09MPa, heat to 110-125°C, react for 2.5-3h, and then cool to room temperature; Step 4: Pour in 1.5-2g of diluent, stir evenly, then add 0.1-0.25g of initiator and 0.02-0.04g of accelerator, stir evenly; Step 5: adding 2.2-2.8 g of modified carbon fiber and 0.4-0.8 g of composite filler, and mixing well to synthesize bio-based degradable polyester resin; The preparation method of the modified carbon fiber: (1) Soak 8-15 g of carbon fiber in 25-45 mL of the mixed solution; (2) Place in a 460-500W UV reactor and react for 30-40 minutes; (3) Washing with chloroform 2-4 times, and then drying in a drying oven at 50-60°C for 45-60 minutes to obtain modified carbon fiber; In (1), the mixed solution is a mixed solution of a mercapto polymer, chloroform and a,a-dimethoxy-a-acetophenone, and the volume ratio thereof is (0.2-0.6):0.5:(0.8-2); The preparation method of the thiol polymer is as follows: 1-3 g of bismaleimide, 0.8-2 g of trimethylolpropane tris(3-mercaptopropionate) and 0.9-3 g of triethylamine are mixed, 15-25 mL of dichloromethane is added, the mixture is stirred and heated to 45-60° C., and reacted for 3.5-4 hours under a nitrogen atmosphere to obtain the thiol polymer; The preparation method of the composite filler is: S1. Mix 30-36 mL of isopropanol and 10-20 mL of N,N-dimethylformamide and stir for 10-20 min; S2, add 0.4-0.9g of tetrabutyl titanate, continue mixing and stirring for 10-15min, pour the mixture into a sealed container, heat to 200-220°C, and react for 20-24h; S3, take out and cool to room temperature, wash with anhydrous ethanol 3-5 times, centrifuge at a speed of 2500-3500r / mi for 8-10min, and then wash with deionized water 3-5 times; S4, first place in a blast oven at 55-60°C to dry for 10-12h, then place in a muffle furnace, heat to 420-450°C, and calcine for 2h; S5, pour into 65-80mL of H2PtCl6·6H20 solution with a concentration of 4g / L, stir and react for 22-24h, and then place under a xenon lamp for irradiation; S6. After centrifugation at a speed of 5000-7000 r / min for 10-13 min, wash with deionized water 2-4 times, and then dry in a drying oven at 50-60° C. for 22-24 h to obtain a composite filler.

2. The process for synthesizing a biodegradable polyester resin according to claim 1, characterized in that: In the step 1, the catalyst is tetrabutyl titanate and the inhibitor is hydroquinone.

3. The process for synthesizing a biodegradable polyester resin according to claim 1, characterized in that: In the step 4, the diluent is dimethyl itaconate, the initiator is cyclohexanone peroxide, and the accelerator is cobalt cyclohexaneate.

4. The process for synthesizing a bio-based degradable polyester resin according to claim 1, characterized in that: In the step S4, the heating rate is 5-7°C / min.

5. The process for synthesizing a bio-based degradable polyester resin according to claim 1, characterized in that: In S5, the xenon lamp is equipped with a 400-420nm filter, the irradiation intensity is 280-300W, and the irradiation time is 50-60min.

6. Use of the bio-based degradable polyester resin according to claim 1 in packaging materials.

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