Environment-friendly paint prepared from recycled waste materials

Abstract

The invention discloses environment-friendly paint prepared from recycled waste, and relates to the technical field of coating preparation, and the environment-friendly paint is prepared from the following components in parts by mass: 25-30 parts of regenerated waterborne polyester resin and 2-3 parts of modified graphene-polyaniline powder. The method has the advantages that the regenerated resin, the functional waste particles and the nano anticorrosive material are subjected to formula design and multi-stage compounding, and a step-by-step dispersion and precise shearing process is combined, so that high-valued utilization of the waste and performance complementation among components are realized, and compared with the prior art, the product has the advantages that the raw material cost and the carbon footprint are remarkably reduced, and meanwhile, the production cost is reduced. The paint achieves excellent corrosion protection, mechanical strength and construction stability, breaks through the bottleneck of insufficient performance of the traditional recycled paint, and has wide application prospects in the fields of building corrosion prevention, industrial maintenance and the like with dual requirements on environmental protection and cost.

Description

Technical Field

[0001] This invention relates to the field of coating preparation technology, and in particular to an environmentally friendly paint prepared from recycled waste materials. Background Technology

[0002] Paint is a material that forms a solid film by being coated on the surface of an object, serving decorative, protective, or functional purposes. With increasingly stringent environmental regulations, paints made primarily from multi-source solid waste such as waste plastics, industrial slag, and waste paint films have emerged.

[0003] In the existing technology, there have been explorations of preparing coatings using single waste materials. For example, waste PET is alcoholyzed to synthesize polyester resin for use in coatings. However, the resulting resin often lacks sufficient hydrophilicity, stability and corrosion resistance. Using waste paint film as filler has problems such as poor compatibility with the substrate and affecting the density of the paint film. Therefore, it is necessary to design an environmentally friendly paint prepared from recycled waste materials. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides an environmentally friendly paint prepared from recycled waste materials, thus solving the problems mentioned in the background section.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: An environmentally friendly paint prepared from recycled waste materials, comprising the following components in parts by weight: 25-30 parts recycled waterborne polyester resin, 2-3 parts modified graphene-polyaniline powder, 12-16 parts waste paint film particles, 30-40 parts activated slag powder, 3-4 parts zinc phosphate, 4-5 parts wetting and dispersing agent, 10-12 parts deionized water, 0.3-0.8 parts thickener A, 0.2-0.6 parts thickener B, 0.3-0.6 parts defoamer, and 10-12 parts film-forming aid; The wetting and dispersing agent is a high molecular weight carboxylate copolymer solution (HT-5025 can be used specifically). Thickener A is an acrylate copolymer emulsion (ASE-60 can be used specifically); Thickener B is a hydrophobically modified ethylene oxide polyurethane block copolymer (specifically, UR 7310 can be used). The defoamer is an organic polymer-modified polysiloxane emulsion (HT-108 can be used specifically). The film-forming aid is dodecyl alcohol ester.

[0006] Furthermore, the preparation steps of the recycled waterborne polyester resin are as follows: Step A1: Under a nitrogen atmosphere, crush waste PET bottles into 5×5mm PET fragments, add neopentyl glycol and zinc acetate, heat to 180-190℃, rotate at 150-200 rpm, stir and react for 2-4 hours to obtain a mixture. Step A2: Under a nitrogen atmosphere, cool to 140-160℃, add isophthalic acid and adipic acid to the mixture, heat to 200-210℃, react for 2-3 hours, cool to 180-190℃, add trimellitic anhydride, react for 1-1.5 hours, reduce pressure to -0.095 to -0.1 MPa, react for 2-3 hours, the reaction is complete, and a resin solution is obtained; Step A3: Cool to 80-100℃, stir at 300-400 rpm, add dimethylethanolamine to the resin solution, stir for 8-12 minutes, cool to 70-80℃, add deionized water, stir for 8-12 minutes, cool to 25-35℃, add triethylamine to adjust the pH to 8-8.5, filter, and obtain regenerated waterborne polyester resin; This step imparts flexibility to the resin through the branched structure of neopentyl glycol, while isophthalic acid and adipic acid synergistically regulate the balance between rigidity and toughness. Tripterygium anhydride introduces hydrophilic carboxyl groups. Through their synergistic effects, a regenerated resin with good adhesion, water resistance, and storage stability is obtained, providing the core film-forming substance for the subsequent preparation of high-performance environmentally friendly coatings.

[0007] Furthermore, the mass ratio of PET fragments, neopentyl glycol, and zinc acetate in step A1 is 1:0.6-0.8:0.003-0.005; The mass ratio of the mixture, isophthalic acid, adipic acid and trimellitic anhydride mentioned in step A2 is 1:0.2-0.3:0.05-0.1:0.08-0.12; The mass ratio of the resin solution, dimethylethanolamine and deionized water in step A3 is 1:0.07-0.08:1.3-1.5.

[0008] Furthermore, the preparation steps of the modified graphene-polyaniline powder are as follows: Step B1: Add graphene oxide to deionized water, cool to 0-4℃, stir at 300-400 rpm for 25-35 min, add aminobenzene, stir for 15-25 min, add sodium persulfate aqueous solution, react for 4-6 h, the reaction is complete, and a composite dispersion is obtained. Step B2: Heat to 25-35℃, add L-ascorbic acid to the composite dispersion, heat to 60-70℃, stir at 300-500 rpm for 2-3 hours, add 0.36wt% hydrochloric acid solution to adjust pH to 4-5, add KH-500, stir at 400-500 rpm for 3-4 hours, centrifuge, wash, vacuum dry for 12-24 hours, grind to obtain modified graphene-polyaniline powder; This step achieves dual enhancement of physical shielding and active corrosion protection through the synergistic modification of graphene and polyaniline. L-ascorbic acid simultaneously reduces graphene and stabilizes polyaniline doping. KH-500 introduces organic functional groups on the surface of the composite material, significantly improving its dispersibility and interfacial bonding in the resin matrix, ultimately obtaining a functional powder that combines long-term corrosion protection with good workability.

[0009] Furthermore, in step B1, the mass ratio of graphene oxide, aminobenzene, and sodium persulfate aqueous solution is 1:0.5-0.8:0.8-1.2; The mass ratio of the composite dispersion, L-ascorbic acid and KH-500 in step B2 is 1:2-3:0.03-0.05.

[0010] Furthermore, the preparation steps for the waste paint film particles are as follows: Collect waste paint film from building or industrial anti-corrosion projects, crush it into paint film particles of 80-120 mesh, add silane coupling agent KH-500 and anhydrous ethanol to the paint film particles, stir at 1500-2000 rpm for 20-30 minutes, filter, heat to 80-90℃, dry for 2-3 hours, crush, and pass through an 80 mesh sieve to obtain waste paint film particles. KH-500 was used to modify the surface of waste paint film particles, transforming them from inert fillers into active reinforcing components, which significantly improved the interfacial bonding force with the resin matrix and effectively avoided paint film defects caused by poor compatibility. The mass ratio of the paint film particles, KH-500 and anhydrous ethanol is 1:3-5:30-40.

[0011] Furthermore, the preparation steps of the activated slag powder are as follows: Step C1: Dry the slag or coal powder at 100-110℃, crush it into 800-1000 mesh slag powder, add 6wt% dilute phosphoric acid solution to the slag powder, heat to 60-70℃, stir at 300-400 rpm for 1-2 hours, wash, filter, heat to 90-100℃, dry for 2-4 hours, and the drying is completed to obtain activated slag powder; Step C2: Transfer the activated slag powder into a high-speed mixer, heat it to 80-90℃, rotate it at 600-800 rpm, add stearic acid ethanol solution, stir and react for 20-30 minutes. After the reaction is complete, pulverize it and pass it through a 400-mesh sieve to obtain activated slag micro powder. This step transforms industrial slag into a high-performance rust-preventive filler through the synergistic effect of dilute phosphoric acid and stearic acid, giving it both chemical corrosion protection and physical reinforcement functions, thus realizing the high-value application of industrial solid waste in coatings.

[0012] Furthermore, the mass ratio of the slag powder to the 6wt% dilute phosphoric acid solution in step C1 is 1:2-3; In step C2, the mass ratio of activated slag powder to stearic acid ethanol solution is 1:0.06-0.1, and the mass ratio of stearic acid to ethanol in the stearic acid ethanol solution is 1:4-5.

[0013] A method for preparing an environmentally friendly paint made from recycled waste materials, comprising the following steps: Step S1: Add HT-5025 and modified graphene-polyaniline powder to deionized water, heat to 25-35℃, stir at 300-500 rpm for 10-12 minutes, stir at 1400-1600 rpm for 30-40 minutes, and the slurry is obtained after stirring is completed. Step S2: Add ASE-60 to the slurry, heat to 30-40℃, stir at 500-700 rpm for 8-10 minutes, add zinc phosphate and activated slag powder, stir at 1150-1250 rpm for 20-26 minutes to obtain a mixture; Step S3: Add the recycled waterborne polyester resin, dodecyl alcohol ester and HT-108a to the mixture, stir at 400-500 rpm for 10-12 minutes, add waste paint film particles, stir at 200-300 rpm for 8-10 minutes, add 25wt% ammonia to adjust the pH to 8.5-9.0, add UR 7310 and HT-108b, stir for 4-6 minutes, and pass through an 80-mesh sieve to obtain environmentally friendly paint; This step, through the synergy of various components and a unique step-by-step feeding and shearing process, optimizes the performance of the paint and recycles resources, ultimately resulting in a green coating that combines excellent corrosion resistance, physical strength, and construction stability.

[0014] The mass ratio of deionized water, HT-5025, and modified graphene-polyaniline powder in step S1 is 1:0.4-0.5:0.2-0.3. The mass ratio of the slurry, ASE-60, zinc phosphate, and activated slag powder in step S2 is 1:0.2-0.4:0.1-0.2:1.6-2.2; The mass ratio of the mixture, recycled waterborne polyester resin, dodecyl alcohol ester, waste paint film particles, UR 7310, HT-108a and HT-108b in step S3 is 1:0.5-0.6:0.2-0.3:0.2-0.4:0.004-0.01:0.003-0.005:0.003-0.005.

[0015] The beneficial effects of this invention are as follows: This invention provides an environmentally friendly paint prepared from recycled waste materials. By formulating and multi-stage compounding recycled resin, functionalized waste particles, and nano-anticorrosion materials, and combining stepwise dispersion and precise shearing processes, this invention achieves high-value utilization of waste materials and complementary performance between components. Compared with existing technologies, this product significantly reduces raw material costs and carbon footprint while achieving excellent anticorrosion protection, mechanical strength, and construction stability. It breaks through the bottleneck of insufficient performance of traditional recycled coatings and has broad application prospects in fields such as building corrosion protection and industrial maintenance where there are dual requirements for environmental protection and cost. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments.

[0017] Example 1: Preparation of a recycled waterborne polyester resin S1: Under a nitrogen atmosphere, waste PET bottles are crushed into 5×5mm PET fragments. 600g of neopentyl glycol and 5g of zinc acetate are added to 1000g of PET fragments. The mixture is heated to 180℃, rotated at 200rpm, and stirred for 2 hours to obtain a mixed solution. S2: Under a nitrogen atmosphere, the temperature was lowered to 140℃, and 300g of isophthalic acid and 50g of adipic acid were added to 1000g of a mixed solution. The temperature was raised to 210℃ and reacted for 2 hours. The temperature was lowered to 190℃, and 80g of trimellitic anhydride was added. The reaction was carried out for 1.5 hours. The pressure was lowered to -0.095MPa and the reaction was carried out for 3 hours. The reaction was completed, and a resin solution was obtained. S3: Cool to 80℃, stir at 400 rpm, add 70g of dimethylethanolamine to 1000g of resin solution, stir for 12 minutes, cool to 70℃, add 1500g of deionized water, stir for 8 minutes, cool to 35℃, add triethylamine to adjust pH to 8-8.5, filter, and obtain regenerated waterborne polyester resin.

[0018] Example 2: Preparation of a recycled waterborne polyester resin S1: Under a nitrogen atmosphere, waste PET bottles are crushed into 5×5mm PET fragments. 700g of neopentyl glycol and 4g of zinc acetate are added to 1000g of PET fragments. The mixture is heated to 185℃, rotated at 175rpm, and stirred for 3h to obtain a mixed solution. S2: Under a nitrogen atmosphere, the temperature was lowered to 150℃, and 250g of isophthalic acid and 75g of adipic acid were added to 1000g of a mixed solution. The temperature was raised to 205℃ and the reaction was carried out for 2.5h. The temperature was lowered to 185℃, and 100g of trimellitic anhydride was added. The reaction was carried out for 1.25h. The pressure was lowered to -0.0975MPa and the reaction was carried out for 2.5h. The reaction was completed, and a resin solution was obtained. S3: Cool to 90℃, stir at 350 rpm, add 75g of dimethylethanolamine to 1000g of resin solution, stir for 10min, cool to 75℃, add 1400g of deionized water, stir for 10min, cool to 30℃, add triethylamine to adjust pH to 8-8.5, filter, and obtain regenerated waterborne polyester resin.

[0019] Example 3: Preparation of a recycled waterborne polyester resin S1: Under a nitrogen atmosphere, waste PET bottles are crushed into 5×5mm PET fragments. 800g of neopentyl glycol and 3g of zinc acetate are added to 1000g of PET fragments. The mixture is heated to 190℃, rotated at 150rpm, and stirred for 4h to obtain a mixed solution. S2: Under a nitrogen atmosphere, the temperature was lowered to 160℃, and 200g of isophthalic acid and 100g of adipic acid were added to 1000g of a mixed solution. The temperature was raised to 200℃ and reacted for 3 hours. The temperature was lowered to 180℃, and 120g of trimellitic anhydride was added. The reaction was carried out for 1 hour. The pressure was lowered to -0.1MPa and the reaction was carried out for 2 hours. The reaction was completed, and a resin solution was obtained. S3: Cool to 100℃, rotate at 300 rpm, add 80g of dimethylethanolamine to 1000g of resin solution, stir for 8 minutes, cool to 80℃, add 1300g of deionized water, stir for 12 minutes, cool to 25℃, add triethylamine to adjust pH to 8-8.5, filter, and obtain regenerated waterborne polyester resin.

[0020] Example 4: Preparation of a modified graphene-polyaniline powder S1: Add 1000g of graphene oxide to 3000mL of deionized water, cool to 0℃, stir at 400rpm for 25min, add 800g of aminobenzene, stir for 15min, add 1200g of sodium persulfate aqueous solution, react for 4h, the reaction is complete, and a composite dispersion is obtained. S2: Heat to 25℃, add 3000g of L-ascorbic acid to 1000g of composite dispersion, heat to 60℃, stir at 500rpm for 2h, add 0.36wt% hydrochloric acid solution to adjust pH to 4-5, add 50g of KH-500, stir at 400rpm for 4h, centrifuge, wash, vacuum dry for 12h, grind to obtain modified graphene-polyaniline powder.

[0021] Example 5: Preparation of a modified graphene-polyaniline powder S1: Add 1000g of graphene oxide to 3000mL of deionized water, cool to 2℃, stir at 350rpm for 30min, add 650g of aminobenzene, stir for 20min, add 1000g of sodium persulfate aqueous solution, react for 5h, the reaction is complete, and a composite dispersion is obtained. S2: Heat to 30℃, add 2500g of L-ascorbic acid to 1000g of composite dispersion, heat to 65℃, stir at 400rpm for 2.5h, add 0.36wt% hydrochloric acid solution to adjust pH to 4-5, add 40g of KH-500, stir at 450rpm for 3.5h, centrifuge, wash, vacuum dry for 18h, grind to obtain modified graphene-polyaniline powder.

[0022] Example 6: Preparation of a modified graphene-polyaniline powder S1: Add 1000g of graphene oxide to 3000mL of deionized water, cool to 4℃, stir at 300rpm for 35min, add 500g of aminobenzene, stir for 25min, add 800g of sodium persulfate aqueous solution, react for 6h, the reaction is complete, and a composite dispersion is obtained. S2: Heat to 35℃, add 2000g of L-ascorbic acid to 1000g of composite dispersion, heat to 70℃, stir at 300rpm for 3h, add 0.36wt% hydrochloric acid solution to adjust pH to 4-5, add 30g of KH-500, stir at 500rpm for 3h, centrifuge, wash, vacuum dry for 24h, grind to obtain modified graphene-polyaniline powder.

[0023] Example 7: Preparation of waste paint film particles Collect waste paint film from building or industrial anti-corrosion projects, crush it into 80-mesh paint film particles, add 500g of silane coupling agent KH-500 and 3000g of anhydrous ethanol to 100g of paint film particles, stir at 2000rpm for 20min, filter, heat to 90℃, dry for 2h, crush, and pass through an 80-mesh sieve to obtain waste paint film particles.

[0024] Example 8: Preparation of waste paint film particles Collect waste paint film from building or industrial anti-corrosion projects, crush it into 100-mesh paint film particles, add 400g of silane coupling agent KH-500 and 3500g of anhydrous ethanol to 100g of paint film particles, stir at 1750rpm for 25min, filter, heat to 85℃, dry for 2.5h, crush, and pass through an 80-mesh sieve to obtain waste paint film particles.

[0025] Example 9: Preparation of waste paint film particles Collect waste paint film from building or industrial anti-corrosion projects, crush it into 120-mesh paint film particles, add 300g of silane coupling agent KH-500 and 4000g of anhydrous ethanol to 100g of paint film particles, stir at 1500rpm for 30min, filter, heat to 80℃, dry for 3h, crush, and pass through an 80-mesh sieve to obtain waste paint film particles.

[0026] Example 10: Preparation of an activated slag powder S1: Dry the slag or coal powder at 100℃, crush it into 1000 mesh slag powder, add 2000g of 6wt% dilute phosphoric acid solution to 1000g of slag powder, heat to 70℃, rotate at 300rpm, stir for 2h, wash, filter, heat to 90℃, dry for 4h, drying is completed, and activated slag powder is obtained. S2: Transfer 1000g of activated slag powder into a high-speed mixer, heat to 80℃, rotate at 800rpm, add 60g of stearic acid ethanol solution, stir and react for 30min. After the reaction is complete, pulverize and pass through a 400-mesh sieve to obtain activated slag micro powder.

[0027] Example 11: Preparation of an activated slag powder S1: Dry the slag or coal powder at 105℃, crush it into 900 mesh slag powder, add 2500g of 6wt% dilute phosphoric acid solution to 1000g of slag powder, heat to 65℃, rotate at 350rpm, stir for 1.5h, wash, filter, heat to 95℃, dry for 3h, drying is completed, and activated slag powder is obtained. S2: Transfer 1000g of activated slag powder into a high-speed mixer, heat to 85℃, rotate at 700rpm, add 80g of stearic acid ethanol solution, stir and react for 25min. After the reaction is complete, pulverize and pass through a 400-mesh sieve to obtain activated slag micro powder.

[0028] Example 12: Preparation of an activated slag powder S1: Dry the slag or coal powder at 110℃, crush it into 800 mesh slag powder, add 3000g of 6wt% dilute phosphoric acid solution to 1000g of slag powder, heat to 60℃, rotate at 400rpm, stir for 1h, wash, filter, heat to 100℃, dry for 2h, drying is completed, and activated slag powder is obtained. S2: Transfer 1000g of activated slag powder into a high-speed mixer, heat to 90℃, rotate at 600rpm, add 100g of stearic acid ethanol solution, stir and react for 20min. After the reaction is complete, pulverize and pass through a 400-mesh sieve to obtain activated slag micro powder.

[0029] Example 13: Preparation of an environmentally friendly paint made from recycled waste materials S1: Add 400g of HT-5025 and 300g of modified graphene-polyaniline powder to 1000g of deionized water, heat to 25℃, stir at 500rpm for 10min, stir at 1600rpm for 30min, and the slurry is obtained after stirring is completed. S2: Add 200g of ASE-60 to 1000g of slurry, heat to 40℃, stir at 500rpm for 10min, add 100g of zinc phosphate and 2200g of activated slag powder, stir at 1150rpm for 26min to obtain a mixture. S3: Add 500g of recycled waterborne polyester resin, 300g of dodecyl alcohol ester and 3g of HT-108a to 1000g of mixture, stir at 500rpm for 10min, add 400g of waste paint film particles, stir at 200rpm for 10min, add 25wt% ammonia to adjust pH to 8.5-9.0, add 4g of UR 7310 and 5g of HT-108b, stir for 4min, and pass through an 80-mesh sieve to obtain environmentally friendly paint.

[0030] Example 14: Preparation of an environmentally friendly paint made from recycled waste materials S1: Add 450g of HT-5025 and 250g of modified graphene-polyaniline powder to 1000g of deionized water, heat to 30℃, stir at 400rpm for 11min, stir at 1500rpm for 35min, and the slurry is obtained after stirring is completed. S2: Add 300g of ASE-60 to 1000g of slurry, heat to 35℃, stir at 600rpm for 9min, add 150g of zinc phosphate and 1900g of activated slag powder, stir at 1200rpm for 23min to obtain a mixture. S3: Add 550g of recycled waterborne polyester resin, 250g of dodecyl alcohol ester and 4g of HT-108a to 1000g of mixture, stir at 450rpm for 11min, add 300g of waste paint film particles, stir at 250rpm for 9min, add 25wt% ammonia to adjust pH to 8.5-9.0, add 7g of UR 7310 and 4g of HT-108b, stir for 5min, and pass through an 80-mesh sieve to obtain environmentally friendly paint.

[0031] Example 15: Preparation of an environmentally friendly paint made from recycled waste materials S1: Add 500g of HT-5025 and 200g of modified graphene-polyaniline powder to 1000g of deionized water, heat to 35℃, stir at 300rpm for 12min, stir at 1400rpm for 40min, and the slurry is obtained after stirring is completed. S2: Add 400g of ASE-60 to 1000g of slurry, heat to 30℃, stir at 700rpm for 8min, add 200g of zinc phosphate and 1600g of activated slag powder, stir at 1250rpm for 20min to obtain a mixture. S3: Add 600g of recycled waterborne polyester resin, 200g of dodecyl alcohol ester and 5g of HT-108a to 1000g of mixture, stir at 400rpm for 12min, add 200g of waste paint film particles, stir at 300rpm for 8min, add 25wt% ammonia to adjust pH to 8.5-9.0, add 10g of UR 7310 and 3g of HT-108b, stir for 6min, and pass through an 80-mesh sieve to obtain environmentally friendly paint.

[0032] Comparative Example 1: Compared with Example 13, this comparative example only replaces the modified graphene-polyaniline powder with ordinary graphene powder. All other steps and parameters are the same, and will not be repeated here. The final result is a recyclable new paint.

[0033] Comparative Example 2: Compared with Example 13, this comparative example only did not add UR 7310 in the preparation process of an environmentally friendly paint made from recycled waste. All other steps and parameters were the same, and will not be repeated here. The final result is a new type of recyclable paint.

[0034] Comparative Example 3: Compared with Example 13, this comparative example only omits the addition of ammonia to adjust the pH during the preparation of an environmentally friendly paint made from recycled waste. All other steps and parameters are the same, and will not be repeated here. The final result is a new type of recyclable paint.

[0035] Performance testing: Corrosion resistance test: According to the GB / T 1771-2022 testing standard, a salt spray test chamber was used: 1. Take a cold-rolled steel plate of 150mm×70mm×0.8mm, spray the paint to be tested evenly onto the cleaned cold-rolled steel plate, control the dry film thickness to be (80±10)μm, cure at room temperature for 7d, and make a test sample. 2. Make two intersecting "X"-shaped scratches on the test sample, penetrating the paint film to the metal substrate. Place the sample in a salt spray test chamber at a 20° angle to the vertical direction and spray continuously for 240 hours. At the 72h, 168h and 240h, take out the sample, gently rinse off the surface salt deposits with clean water, and immediately observe the scratches and the width of the corrosion spread on one side of the surrounding area (mm) with a magnifying glass.

[0036] Table 1 Corrosion Resistance Test Results

[0037] Adhesion test: According to the GB / T 9286-2021 testing standard, a cross-cutting tool with a blade spacing of 2mm was used. 1. Take a cold-rolled steel plate of 150mm×70mm×0.8mm, spray the paint to be tested evenly onto the cleaned steel plate, control the dry film thickness to be (80±10)μm, cure at room temperature for 7d, and make a test sample. 2. Using a grid cutter, make six horizontal and six vertical cuts on the surface of the test sample, penetrating the paint film to the metal substrate. Take a 75mm long piece of pressure-sensitive tape and cover its center area over the grid. Within 120 seconds of applying the tape, peel it off. 3. Use a magnifying glass to observe the paint film peeling in the grid area and assess the adhesion level.

[0038] Table 2 Adhesion Test Results

[0039] Data Analysis: As can be seen from Tables 1-2, the environmentally friendly paint made from recycled waste prepared in the embodiments of the present invention exhibits excellent comprehensive performance. This proves that the present invention has successfully achieved high-performance conversion of multi-source waste by systematically designing and synergistically compounding recycled resin, functionalized waste particles and nanocomposite materials. The product has outstanding protective properties, strong adhesion and good formulation process stability. In contrast, Comparative Example 1, which replaced the modified graphene-polyaniline composite powder with ordinary graphene powder, showed a significant deterioration in its anti-corrosion performance and adhesion. This was because ordinary graphene could only provide physical shielding and lacked the active anti-corrosion mechanism of polyaniline components forming a passivation film on the metal surface through redox reactions. As a result, corrosion spread rapidly at the scratches. At the same time, the unmodified graphene had a weaker interface with the resin matrix, which affected the overall adhesion of the paint film. Comparative Example 2, due to the absence of thickener UR 7310, experienced a decrease in its application leveling and film density. This was because the lack of this associative polyurethane thickener prevented the coating from achieving optimal viscosity and leveling under high shear, thus affecting the quality and uniformity of the film formation. Corrosive media were more likely to penetrate the film, and the film cohesion decreased, resulting in a larger area of ​​film peeling during cross-cut tests. In contrast, Comparative Example 3, which did not use ammonia to adjust the pH value of the system, suffered severe damage to the storage stability and integrity of the paint film. This was because pH imbalance caused changes in the dissociation state of the carboxylate groups of the water-based resin, leading to resin pre-flocculation, pigment and filler flocculation, and failure of the thickener ASE-60. The resulting paint film had numerous defects and almost lost all protective and adhesion functions.

[0040] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.

Claims

1. An environmentally friendly paint prepared from recycled waste material, characterized in that, The preparation steps of the modified graphene-polyaniline powder are as follows: The wetting dispersant is a high molecular carboxylic acid salt copolymer solution; The thickening agent A is an acrylate copolymer emulsion; The thickening agent B is a hydrophobically modified ethylene oxide polyurethane block copolymer; The defoaming agent is an organic polymer modified polysiloxane emulsion; The film forming aid is dodecanol ester.

2. An eco-friendly paint prepared from recycled waste material according to claim 1, characterized in that, The preparation steps of the modified graphene-polyaniline powder are as follows: Step A1: under a nitrogen atmosphere, the waste PET bottle is crushed into PET fragments of 5*5mm, new pentaerythritol and zinc acetate are added, the temperature is raised to 180-190℃, and stirring is carried out for 2-4h to obtain a mixed solution; Step A2: under a nitrogen atmosphere, the temperature is lowered to 140-160℃, isophthalic acid and adipic acid are added to the mixed solution, the temperature is raised to 200-210℃, and reaction is carried out for 2-3h, the temperature is lowered to 180-190℃, trimellitic anhydride is added, and reaction is carried out for 1-1.5h, the pressure is lowered to -0.095 to -0.1MPa, and reaction is carried out for 2-3h, and the reaction is completed to obtain a resin solution; Step A3: the temperature is lowered to 80-100℃, dimethyl ethanolamine is added to the resin solution, stirring is carried out for 8-12min, the temperature is lowered to 70-80℃, deionized water is added, stirring is carried out for 8-12min, the temperature is lowered to 25-35℃, triethylamine is added to adjust the pH to 8-8.5, and filtration is carried out to obtain the regenerated water-based polyester resin.

3. An eco-friendly paint prepared from recycled waste material according to claim 2, characterized in that, The mass ratio of the PET fragments, new pentaerythritol and zinc acetate in step A1 is 1:0.6-0.8:0.003-0.005; The mass ratio of the mixed solution, isophthalic acid, adipic acid and trimellitic anhydride in step A2 is 1:0.2-0.3:0.05-0.1:0.08-0.12; The mass ratio of the resin solution, dimethyl ethanolamine and deionized water in step A3 is 1:0.07-0.08:1.3-1.

5.

4. An eco-friendly paint prepared from recycled waste material as claimed in claim 1, wherein, The preparation steps of the modified graphene-polyaniline powder are as follows: Step B1: graphene oxide is added to deionized water, the temperature is lowered to 0-4℃, stirring is carried out for 25-35min, amino benzene is added, stirring is carried out for 15-25min, aqueous sodium persulfate solution is added, and reaction is carried out for 4-6h, and the reaction is completed to obtain a composite dispersion solution; Step B2: the temperature is raised to 25-35℃, L-ascorbic acid is added to the composite dispersion solution, the temperature is raised to 60-70℃, stirring is carried out for 2-3h, 0.36wt% hydrochloric acid solution is added to adjust the pH to 4-5, silane coupling agent KH-500 is added, stirring is carried out for 3-4h, centrifugal separation is carried out, washing is carried out, vacuum drying is carried out for 12-24h, and grinding is carried out to obtain the modified graphene-polyaniline powder.

5. An eco-friendly paint prepared from recycled waste material according to claim 4, characterized in that, The mass ratio of the graphene oxide, amino benzene and aqueous sodium persulfate solution in step B1 is 1:0.5-0.8:0.8-1.2; The mass ratio of the composite dispersion liquid, L-ascorbic acid and KH-500 in step B2 is 1:2-3:0.03-0.

05.

6. An eco-friendly paint prepared from recycled waste material as claimed in claim 1, wherein, The preparation steps of the waste paint film particles are as follows: Collect the waste paint film of building or industrial anti-corrosion engineering, crush to 80-120 mesh paint film particles, add silane coupling agent KH-500 and anhydrous ethanol to the paint film particles, stir for 20-30 min, filter, heat to 80-90℃, dry for 2-3 h, crush, pass through 80 mesh screen, and obtain the waste paint film particles; The mass ratio of the paint film particles, KH-500 and anhydrous ethanol is 1:3-5:30-40.

7. An eco-friendly paint prepared from recycled waste material as claimed in claim 1, wherein, The preparation steps of the activated slag powder are as follows: Step C1: dry the slag or coal powder at 100-110℃, crush to 800-1000 mesh slag powder, add 6wt% dilute phosphoric acid solution to the slag powder, heat to 60-70℃, stir for 1-2 h, wash, filter, heat to 90-100℃, dry for 2-4 h, and obtain the activated slag powder after drying; Step C2: transfer the activated slag powder into a high-speed mixer, heat to 80-90℃, add stearic acid ethanol solution, stir for 20-30 min, complete the reaction, crush, pass through 400 mesh screen, and obtain the activated slag powder.

8. An eco-friendly paint prepared from recycled waste material according to claim 7, characterized in that, The mass ratio of the slag powder and 6wt% dilute phosphoric acid solution in step C1 is 1:2-3; The mass ratio of the activated slag powder and stearic acid ethanol solution in step C2 is 1:0.06-0.1, and the mass ratio of stearic acid and ethanol in the stearic acid ethanol solution is 1:4-5.

9. A method of preparing an eco-friendly paint from recycled waste material according to any one of claims 1-8, characterized in that, The preparation steps are as follows: Step S1: add the high molecular carboxylate copolymer solution and modified graphene-polyaniline powder into deionized water, heat to 25-35℃, stir for 10-12 min, stir for 30-40 min, complete the stirring, and obtain the slurry; Step S2: add the acrylate copolymer emulsion into the slurry, heat to 30-40℃, stir for 8-10 min, add zinc phosphate and activated slag powder, stir for 20-26 min, and obtain the mixture; Step S3: add the regenerated water-based polyester resin, dodecanol ester and organic polymer modified polysiloxane emulsion a into the mixture, stir for 10-12 min, add the waste paint film particles, stir for 8-10 min, add 25wt% ammonia water to adjust the pH to 8.5-9.0, add the hydrophobic modified ethylene oxide polyurethane block copolymer and organic polymer modified polysiloxane emulsion b, stir for 4-6 min, pass through 80 mesh screen, and obtain the environment-friendly paint.

10. A method of preparing an eco-friendly paint from recycled waste material according to claim 9, characterized in that, The mass ratio of the deionized water, high molecular carboxylate copolymer solution and modified graphene-polyaniline powder in step S1 is 1:0.4-0.5:0.2-0.3; The mass ratio of the slurry, acrylate copolymer emulsion, zinc phosphate and activated slag powder in step S2 is 1:0.2-0.4:0.1-0.2:1.6-2.2; The mass ratio of the mixture, the reclaimed aqueous polyester resin, the dodecanol ester, the waste paint film particles, the hydrophobically modified ethylene oxide urethane block copolymer, the organic polymer-modified silicone emulsion a, and the organic polymer-modified silicone emulsion b in step S3 is 1:0.5-0.6:0.2-0.3:0.2-0.4:0.004-0.01:0.003-0.005:0.003-0.005.

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