Plastic bottle cap resistant to chemicals, preparation method of plastic bottle cap and application of plastic bottle cap in cosmetic packaging

Abstract

The invention discloses a chemical-resistant plastic bottle cap as well as a preparation method and application thereof in cosmetic packaging, and belongs to the technical field of plastic materials. Comprising the following steps: mixing polyethylene glycol terephthalate, polybutylene terephthalate and a styrene-acrylonitrile-glycidyl methacrylate copolymer to obtain mixed resin; mixing an acrylonitrile-butadiene-styrene copolymer with the mixed resin, a styrene-ethylene-butylene-styrene block copolymer, polypropylene and an auxiliary agent, and carrying out injection molding to obtain a prefabricated product; and coating the surface of the prefabricated product with a nanocellulose / epoxy acrylate graft copolymerization mixture protective agent, and curing to obtain the corrosion-resistant plastic bottle cap. Polyethylene glycol terephthalate, polybutylene terephthalate and the compatilizer are combined, so that the plastic bottle cap with good chemical corrosion resistance and mechanical property is obtained; the surface of the plastic bottle cap is coated with the anticorrosive paint, so that the corrosion resistance of the material is further enhanced.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of plastic materials, and particularly relates to a chemical-resistant plastic bottle cap, a preparation method thereof and application thereof in cosmetic packaging. BACKGROUND

[0002] With the vigorous development of the cosmetic industry, consumers' requirements for product quality, safety and use experience are increasingly improved. As an important part of the product, the performance and quality of cosmetic packaging directly affect the storage stability, safety and market competitiveness of the product. Plastic bottle caps are widely used in the field of cosmetic packaging due to their advantages such as light weight, low cost and easy processing, and are the core sealing components of various lotion bottles, essence bottles, spray bottles and other containers.

[0003] However, the components of cosmetics are complex and diverse, including alcohol, organic solvents, acids, bases, surfactants and various functional active ingredients, which are prone to chemical corrosion of plastic bottle caps during long-term storage. After contacting these chemicals, ordinary plastic bottle caps (such as conventional polyethylene and polypropylene materials) may swell, deform, become brittle, crack and other phenomena, resulting in a decrease in the sealing performance of the bottle cap, which in turn causes problems such as leakage, volatilization, oxidation and microbial contamination of the contents. For example, high-concentration alcohol-containing perfumes or makeup remover can cause ordinary plastic bottle caps to swell, resulting in loose thread structure and inability to tightly screw; the fruit acid component in acidic skin care products can corrode the bottle cap material, making the surface rough and discolored, affecting the appearance and use experience of the product.

[0004] In addition, with the increasing demand for personalized and high-end products in the cosmetic market, special dosage forms (such as high-activity essence, hair dye, nail polish, etc.) and innovative packaging designs (such as pump press type, vacuum bottle, spray bottle, etc.) are constantly emerging, which puts higher requirements on the chemical resistance, structural stability and functional adaptability of the bottle cap. Traditional plastic bottle caps cannot meet the needs of these complex scenarios. For example, pump-type bottle caps need to be used with precision valves, and if the material has insufficient chemical resistance, it may cause component corrosion and failure, affecting the normal use of the product; high-end cosmetics have strict requirements on the texture and appearance of the bottle cap, and discoloration and reduction in gloss caused by chemical corrosion can significantly reduce the product grade. Therefore, it is of great significance to develop a plastic bottle cap that can effectively resist chemical corrosion in cosmetics and has good mechanical properties, processing performance and cost advantage, and to provide a preparation method matched therewith, for improving the quality of cosmetic packaging, ensuring product quality and safety, and promoting the sustainable development of the cosmetic industry. SUMMARY

[0005] The present application aims to provide a chemical-resistant plastic bottle cap, a preparation method thereof and application thereof in cosmetic packaging, for improving the performance of plastic bottle caps in resisting various chemical corrosion in cosmetics.

[0006] The object of the present application can be achieved by the following technical solutions.

[0007] A preparation method of a chemical-resistant plastic bottle cap, comprising the following steps:

[0008] S1, taking polyethylene terephthalate, polybutylene terephthalate, and styrene-acrylonitrile-glycidyl methacrylate copolymer, mixing uniformly, extruding and granulating, water cooling and drawing particles, to obtain a mixed resin;

[0009] S2, taking acrylonitrile-butadiene-styrene copolymer, mixed resin, styrene-ethylene-butylene-styrene block copolymer, polypropylene, and additives, mixing, discharging, extruding and granulating, water cooling and drawing particles, mixing the granulated resin and the foaming agent uniformly, and then putting it into an injection molding machine to form a preform;

[0010] S3, coating the surface of the preform with a protective agent and curing to obtain the plastic bottle cap;

[0011] The protective agent is a nanocellulose / epoxy acrylate graft copolymer mixture.

[0012] As a preferred technical solution of the present application, in step S1, the mass ratio of polyethylene terephthalate, polybutylene terephthalate, and styrene-acrylonitrile-glycidyl methacrylate copolymer is 1.5-3.5:2-4:0.11-0.22.

[0013] As a preferred technical solution of the present application, in step S2, the mass ratio of acrylonitrile-butadiene-styrene copolymer, mixed resin, styrene-ethylene-butylene-styrene block copolymer, polypropylene, additive, and foaming agent is 3-5:5-7:2.5-2.8:78-82:0.8-1.2:1.5-2.

[0014] As a preferred technical solution of the present application, the additive includes ethylene bis-stearamide, magnesium stearate, antioxidant B215, polyethylene wax, nucleating agent NA-21, wollastonite, and ammonium polyphosphate.

[0015] As a preferred technical solution of the present application, the mass ratio of ethylene bis-stearamide, magnesium stearate, antioxidant B215, polyethylene wax, nucleating agent NA-21, wollastonite, and ammonium polyphosphate is 3-4:1-2:1-3:1-3:1-2:1-2:1-2.

[0016] As a preferred technical solution of the present application, the preparation method of the protective agent comprises the following steps:

[0017] A1, take silane coupling agent KH550, anhydrous ethanol, deionized water mixed, adjust pH to 3-5, heated stirring, adding cellulose nanofibril, ultrasonic dispersion, transfer to high pressure hydrothermal kettle under the condition of 120 DEG C, 1MPa sealed 2-3h, after the reaction was taken out, the mixture was obtained material A; the silane coupling agent KH550, anhydrous ethanol, deionized water, cellulose nanofibril of the amount ratio is 1-1.2g: 70-75mL: 8-10mL: 3-4g;

[0018] A2, take emulsifier SE-10N, deionized water mixed, water bath heating stirring conditions, then continue to stir, get material B; the SE-10N, deionized water, epoxy acrylate of the mass ratio is 1-1.2: 20-30: 8-10;

[0019] A3, take tetrahydrofuran, 4-heptyloxy benzoic acid, nano alumina mixed, ultrasonic dispersion, water bath heating reflux stirring in nitrogen atmosphere, centrifugal separation, drying of solid phase, get modified aromatic hydrocarbon monomer; the tetrahydrofuran, 4-heptyloxy benzoic acid, nano alumina of the amount ratio is 50mL: 1.5-1.8g: 1-1.2g;

[0020] A4, take emulsifier SE-10N, deionized water mixed, water bath heating stirring conditions, then continue to stir, get material C; the SE-10N, deionized water, modified aromatic hydrocarbon monomer of the mass ratio is 1-1.2: 20-30: 10-12;

[0021] A5, in the nitrogen atmosphere, take the material B, acrylamide, acrylic acid mixed, 60 DEG C water bath heating stirring, adding sodium thiosulfate, ammonium persulfate, material C, 70 DEG C heat stirring, add the material A, continue to heat stirring, get material D; the material B, acrylamide, acrylic acid, sodium thiosulfate, ammonium persulfate, material C of the mass ratio is 12-16: 4-6: 1-3: 0.6-0.8: 0.4-0.6: 8-10;

[0022] A6, take the material D, deionized water, dispersing agent, defoaming agent, wetting agent, propylene glycol, precipitated barium sulfate, alcohol ester twelve, thickening agent, water based amine curing agent mixed, namely the protective agent; the material D, deionized water, dispersing agent, defoaming agent, wetting agent, propylene glycol, precipitated barium sulfate, alcohol ester twelve, thickening agent, water based amine curing agent of the mass ratio is 50-60: 20-30: 0.4-0.6: 0.2-0.3: 0.1-0.2: 0.1-0.3: 0.1-0.3: 0.2-0.3: 0.1-0.2: 0.1-0.2.

[0023] The chemical resistant plastic bottle cap prepared by the above preparation method.

[0024] The application of the chemical-resistant plastic bottle cap in cosmetic packaging refers to sealing cosmetics.

[0025] The beneficial effects of the present application are:

[0026] (1) The chemical-resistant plastic bottle cap, its preparation method and application in cosmetic packaging disclosed by the present application obtain a plastic bottle cap with good chemical corrosion resistance and mechanical properties by combining polyethylene terephthalate, polybutylene terephthalate and a compatibilizer.

[0027] (2) The chemical-resistant plastic bottle cap, its preparation method and application in cosmetic packaging disclosed by the present application further enhance the corrosion resistance of the material by coating a corrosion-resistant coating on the surface of the plastic bottle cap, using 4-heptyloxybenzoic acid grafted nano-aluminum oxide as a crosslinking site, and synergistically improving the crosslinking degree of the coating with modified nano-cellulose fibrils. DETAILED DESCRIPTION

[0028] In order to further illustrate the technical means and effects adopted by the present application to achieve the predetermined invention purpose, the specific embodiments, structures, features and effects according to the present application are described in detail as follows in combination with examples.

[0029] Example 1

[0030] The preparation method of the chemical-resistant plastic bottle cap comprises the following steps:

[0031] S1, polyethylene terephthalate and polybutylene terephthalate are dried at 120℃ for 4h, and then mixed with styrene-acrylonitrile-glycidyl methacrylate copolymer in a high-speed mixer, extruded and granulated in a twin-screw extruder, water-cooled and drawn into particles, and dried at 120℃ for 2h to obtain a mixed resin; wherein the length-diameter ratio of the twin-screw extruder is 48:1, the natural exhaust port is located at the fourth and seventh segments, the vacuum exhaust port is located at the eleventh segment, the vacuum degree is 0.08MPa, and the rotation speed is 400r / min; the temperature distribution from the feeding section to the die head is: 200℃, 240℃, 240℃, 240℃, 220℃, 220℃, 200℃, 200℃, 180℃, 180℃, 180℃, and the die head temperature is 240℃; the mass ratio of the polyethylene terephthalate, polybutylene terephthalate and styrene-acrylonitrile-glycidyl methacrylate copolymer is 1.5:2:0.11;

[0032] S2, acrylonitrile-butadiene-styrene copolymer is dried at 80℃ for 4h, then mixed with mixed resin, styrene-ethylene-butylene-styrene block copolymer, polypropylene (brand: Maklin, product number: P816230, same below), auxiliary in a high-speed mixer for 10min, discharging, the blended material is extruded and granulated in a twin-screw extruder, water-cooled draw granulation, the granulated material is mixed uniformly with foaming agent azodicarbonamide and then put into an injection molding machine to form a preform; the temperature of the injection molding is 190℃; the mass ratio of the acrylonitrile-butadiene-styrene copolymer, mixed resin, styrene-ethylene-butylene-styrene block copolymer, polypropylene, auxiliary, foaming agent is 3:5:2.5:78:0.8:1.5; the auxiliary includes 3 parts by mass of ethylene bis-stearamide, 1 part by mass of magnesium stearate, 1 part by mass of antioxidant B215, 1 part by mass of polyethylene wax, 1 part by mass of nucleating agent NA-21, 1 part by mass of wollastonite and 1 part by mass of ammonium polyphosphate; the temperature of the first to second zones of the twin-screw extruder is 200℃, the temperature of the third to fifth zones is 200℃, the temperature of the fifth to twelfth zones is 220℃, the screw length-diameter ratio is 48:1, and the rotation speed is 400r / min; the fifth to seventh zones and the ninth to eleventh zones are vacuumized, and the vacuum degree is 0.08MPa;

[0033] S3, the surface of the preform is coated with a protective agent, and the protective layer with a thickness of 0.1mm is formed after curing, thereby obtaining the plastic bottle cap;

[0034] The preparation method of the protective agent comprises the following steps:

[0035] A1, the silane coupling agent KH550, anhydrous ethanol and deionized water are mixed, the pH is adjusted to 3, heated and stirred, the cellulose nanofilament is added, ultrasonic dispersion, and then transferred to a high-pressure hydrothermal kettle for sealing at 120℃ and 1MPa for 2h, and then the mixed solution is taken out, thereby obtaining material A; the mass ratio of the silane coupling agent KH550, anhydrous ethanol, deionized water and cellulose nanofilament is 1g:70mL:8mL:3g;

[0036] A2, the emulsifier SE-10N and deionized water are mixed, the epoxy acrylate is added under the condition of water bath heating and stirring, and then the stirring is continued, thereby obtaining material B; the mass ratio of the SE-10N, deionized water and epoxy acrylate is 1:20:8;

[0037] A3, the tetrahydrofuran, 4-heptyloxybenzoic acid and nano-alumina are mixed and ultrasonic dispersed, heated and stirred under reflux in a nitrogen atmosphere, centrifuged, the solid phase is dried, and a modified aromatic hydrocarbon monomer is obtained; the mass ratio of the tetrahydrofuran, 4-heptyloxybenzoic acid and nano-alumina is 50mL:1.5g:1g;

[0038] A4, take emulsifier SE-10N, deionized water mixed, water bath heating stirring under the condition of adding modified aromatic hydrocarbon monomer, dropwise adding complete after continue stirring, get material C; the mass ratio of SE-10N, deionized water, modified aromatic hydrocarbon monomer is 1:20:10;

[0039] A5, in the nitrogen atmosphere, take the material B, acrylamide, acrylic acid mixed, 60 DEG C water bath heating stirring, add sodium thiosulfate, ammonium persulfate, material C, at 70 DEG C heat preservation stirring, add the material A, continue heat preservation stirring, get material D; the mass ratio of material B, acrylamide, acrylic acid, sodium thiosulfate, ammonium persulfate, material C is 12:4:1:0.6:0.4:8;

[0040] A6, take the material D, deionized water, dispersing agent, defoaming agent, wetting agent, propylene glycol, precipitated barium sulfate, alcohol ester twelve, thickening agent, water-based amine curing agent mixed, namely the protective agent; the mass ratio of material D, deionized water, dispersing agent, defoaming agent, wetting agent, propylene glycol, precipitated barium sulfate, alcohol ester twelve, thickening agent, water-based amine curing agent is 50:20:0.4:0.2:0.1:0.1:0.1:0.2:0.1:0.1; the dispersing agent is BYK-110; the thickening agent is associated thickening agent TT-40; the defoaming agent is BYK-028; the wetting agent is BYK-349; the water-based amine curing agent is EPIKURE 8290-Y-60 (purchased from Guangzhou Huallili Trading Co., Ltd.).

[0041] Example 2

[0042] A method for preparing a chemical-resistant plastic bottle cap comprises the following steps:

[0043] S1, take polyethylene terephthalate, polybutylene terephthalate at 120 DEG C drying 4h, then with styrene-acrylonitrile-glycidyl methacrylate copolymer together into the high-speed mixer mixed uniformly, extruded in a twin-screw extruder, water cooling draw bar granulation, at 120 DEG C drying 2h, get mixed resin; wherein, the length-diameter ratio of the twin-screw extruder is 48:1, the natural exhaust port is located in the fourth and seventh segments, the vacuum exhaust port is located in the eleventh segment, the vacuum degree is 0.08 MPa, the rotation speed is 400 r / min, the temperature distribution from the feeding section to the die head is: 200 DEG C, 240 DEG C, 240 DEG C, 240 DEG C, 220 DEG C, 220 DEG C, 200 DEG C, 200 DEG C, 180 DEG C, 180 DEG C, 180 DEG C, die head: 240 DEG C; the mass ratio of polyethylene terephthalate, polybutylene terephthalate, styrene-acrylonitrile-glycidyl methacrylate copolymer is 2.5:3:0.16;

[0044] S2, acrylonitrile-butadiene-styrene copolymer is dried at 80℃ for 4h, then mixed with mixed resin, styrene-ethylene-butylene-styrene block copolymer, polypropylene, additives in a high-speed mixer for 10min, discharge, the blended material is extruded and granulated in a twin-screw extruder, water-cooled draw granulation, the granulated material is mixed uniformly with foaming agent azodicarbonamide and then put into an injection molding machine to form a preform; the temperature of injection molding is 200℃; the mass ratio of acrylonitrile-butadiene-styrene copolymer, mixed resin, styrene-ethylene-butylene-styrene block copolymer, polypropylene, additives, foaming agent is 4:6:2.7:80:1.0:1.8; the additives include 3.5 parts by mass of ethylene bis-stearamide, 1.5 parts by mass of magnesium stearate, 2 parts by mass of antioxidant B215, 1.5 parts by mass of polyethylene wax, 1.5 parts by mass of nucleating agent NA-21, 1.5 parts by mass of wollastonite and 1.5 parts by mass of ammonium polyphosphate; the temperature of the first to second zones of the twin-screw extruder is 200℃, the temperature of the third to fifth zones is 200℃, the temperature of the fifth to twelfth zones is 220℃, the screw length-diameter ratio is 48:1, and the rotation speed is 400r / min; vacuum is drawn in the fifth to seventh zones and the ninth to eleventh zones, and the vacuum degree is 0.08MPa;

[0045] S3, the surface of the preform is coated with a protective agent, and the protective layer with a thickness of 0.1mm is formed after curing, thereby obtaining the plastic bottle cap;

[0046] The preparation method of the protective agent comprises the following steps:

[0047] A1, the silane coupling agent KH550, anhydrous ethanol and deionized water are mixed, the pH is adjusted to 4, heated and stirred, cellulose nanofilament is added, ultrasonic dispersion, and then transferred to a high-pressure hydrothermal kettle for sealing at 120℃ and 1MPa for 2.5h, and the mixed solution is taken out after the reaction is completed to obtain material A; the mass ratio of the silane coupling agent KH550, anhydrous ethanol, deionized water and cellulose nanofilament is 1.1g:73mL:9mL:3.5g;

[0048] A2, the emulsifier SE-10N and deionized water are mixed, heated and stirred in a water bath, then the epoxy acrylate is added, and the stirring is continued to obtain material B; the mass ratio of SE-10N, deionized water and epoxy acrylate is 1.1:25:9;

[0049] A3, tetrahydrofuran, 4-heptyloxybenzoic acid and nano-alumina are mixed and ultrasonic dispersed, heated and stirred in a water bath under nitrogen atmosphere, centrifuged, the solid phase is dried to obtain a modified aromatic hydrocarbon monomer; the amount ratio of tetrahydrofuran, 4-heptyloxybenzoic acid and nano-alumina is 50mL:1.65g:1.1g;

[0050] A4, take emulsifier SE-10N, deionized water mixed, water bath heating stirring conditions, adding modified aromatic hydrocarbon monomer, dropwise complete after continuous stirring, get material C; the mass ratio of SE-10N, deionized water, modified aromatic hydrocarbon monomer is 1.1:25:11;

[0051] A5, in the atmosphere of nitrogen, take the material B, acrylamide, acrylic acid mixed, 60 DEG C water bath heating stirring, adding sodium thiosulfate, ammonium persulfate, material C, at 70 DEG C heat preservation stirring, adding the material A, continue to heat preservation stirring, get material D; the mass ratio of material B, acrylamide, acrylic acid, sodium thiosulfate, ammonium persulfate, material C is 14:5:2:0.7:0.5:9;

[0052] A6, take the material D, deionized water, dispersing agent, defoaming agent, wetting agent, propylene glycol, precipitated barium sulfate, alcohol ester twelve, thickening agent, water amine curing agent mixed, namely the protective agent; the mass ratio of material D, deionized water, dispersing agent, defoaming agent, wetting agent, propylene glycol, precipitated barium sulfate, alcohol ester twelve, thickening agent, water amine curing agent is 55:25:0.5:0.25:0.15:0.2:0.2:0.25:0.15:0.15; the dispersing agent is BYK-110; the thickening agent is associated thickening agent TT-40; the defoaming agent is BYK-028; the wetting agent is BYK-349; the water amine curing agent is EPIKURE8290-Y-60.

[0053] Example 3

[0054] A method for preparing a chemical-resistant plastic bottle cap comprises the following steps:

[0055] S1, take polyethylene terephthalate, polybutylene terephthalate is dried at 120 DEG C for 4h, then mixed with styrene-acrylonitrile-glycidyl methacrylate copolymer in a high-speed mixer, extruded and granulated in a twin-screw extruder, water-cooled drawbar granulation, dried at 120 DEG C for 2h, to get mixed resin; wherein the length-diameter ratio of the twin-screw extruder is 48:1, the natural exhaust port is located at the fourth and seventh segments, the vacuum exhaust port is located at the eleventh segment, the vacuum degree is 0.08MPa, the rotation speed is 400r / min, the temperature distribution from the feeding section to the die head is: 200 DEG C, 240 DEG C, 240 DEG C, 240 DEG C, 220 DEG C, 220 DEG C, 200 DEG C, 200 DEG C, 180 DEG C, 180 DEG C, 180 DEG C, die head: 240 DEG C; the mass ratio of polyethylene terephthalate, polybutylene terephthalate, styrene-acrylonitrile-glycidyl methacrylate copolymer is 3.5:4:0.22;

[0056] S2, acrylonitrile-butadiene-styrene copolymer is dried at 80℃ for 4h, then mixed with mixed resin, styrene-ethylene-butylene-styrene block copolymer, polypropylene, additives in a high-speed mixer for 10min, discharge, the blended material is extruded and granulated in a twin-screw extruder, water-cooled draw granulation, the granulated material is mixed uniformly with foaming agent azodicarbonamide and then put into an injection molding machine to form a preform; the temperature of injection molding is 210℃; the mass ratio of acrylonitrile-butadiene-styrene copolymer, mixed resin, styrene-ethylene-butylene-styrene block copolymer, polypropylene, additives, foaming agent is 5:7:2.8:82:1.2:2; the additives include 4 parts of ethylene bis-stearamide, 2 parts of magnesium stearate, 3 parts of antioxidant B215, 3 parts of polyethylene wax, 2 parts of nucleating agent NA-21, 2 parts of wollastonite and 2 parts of ammonium polyphosphate; the temperature of the first and second zones of the twin-screw extruder is 200℃, the temperature of the third to fifth zones is 200℃, the temperature of the fifth to twelfth zones is 220℃, the screw length-diameter ratio is 48:1, and the rotation speed is 400r / min; the fifth to seventh zones and the ninth to eleventh zones are vacuumized, and the vacuum degree is 0.08MPa;

[0057] S3, the surface of the preform is coated with a protective agent, and then cured to form a protective layer with a thickness of 0.1mm, thereby obtaining the plastic bottle cap;

[0058] The preparation method of the protective agent comprises the following steps:

[0059] A1, silane coupling agent KH550, anhydrous ethanol and deionized water are mixed, the pH is adjusted to 5, heated and stirred, cellulose nanofilament is added, ultrasonic dispersion, transferred to a high-pressure hydrothermal kettle, sealed at 120℃ and 1MPa for 3h, then the mixed solution is taken out, and material A is obtained; the mass ratio of the silane coupling agent KH550, anhydrous ethanol, deionized water and cellulose nanofilament is 1.2g:75mL:10mL:4g;

[0060] A2, emulsifier SE-10N and deionized water are mixed, heated and stirred in a water bath, then epoxy acrylate is added, and then stirring is continued to obtain material B; the mass ratio of SE-10N, deionized water and epoxy acrylate is 1.2:30:10;

[0061] A3, tetrahydrofuran, 4-heptyloxybenzoic acid and nano-alumina are mixed and ultrasonic dispersed, heated and stirred in a water bath under nitrogen atmosphere, centrifuged, the solid phase is dried to obtain a modified aromatic hydrocarbon monomer; the mass ratio of tetrahydrofuran, 4-heptyloxybenzoic acid and nano-alumina is 50mL:1.8g:1.2g;

[0062] A4, take the emulsifier SE-10N, deionized water mixed, water bath heating stirring under the condition of adding modified aromatic hydrocarbon monomer, dropwise complete after continue stirring, get material C; the mass ratio of SE-10N, deionized water, modified aromatic hydrocarbon monomer is 1.2:30:12;

[0063] A5, in the nitrogen atmosphere, take the material B, acrylamide, acrylic acid mixed, 60 DEG C water bath heating stirring, adding sodium thiosulfate, ammonium persulfate, material C, at 70 DEG C heat preservation stirring, add the material A, continue heat preservation stirring, get material D; the mass ratio of material B, acrylamide, acrylic acid, sodium thiosulfate, ammonium persulfate, material C is 16:6:3:0.8:0.6:10;

[0064] A6, take the material D, deionized water, dispersing agent, defoaming agent, wetting agent, propylene glycol, precipitated barium sulfate, alcohol ester twelve, thickening agent, water amine curing agent mixed, namely the protective agent; the mass ratio of material D, deionized water, dispersing agent, defoaming agent, wetting agent, propylene glycol, precipitated barium sulfate, alcohol ester twelve, thickening agent, water amine curing agent is 60:30:0.6:0.3:0.2:0.3:0.3:0.3:0.2:0.2; the dispersing agent is BYK-110; the thickening agent is associated thickening agent TT-40; the defoaming agent is BYK-028; the wetting agent is BYK-349; the water amine curing agent is EPIKURE 8290-Y-60.

[0065] Comparative example 1

[0066] The difference from example 2 is that the process of preparing mixed resin in step S1 is cancelled, and the polyethylene terephthalate is directly added to the original step S2.

[0067] Comparative example 2

[0068] The difference from example 2 is that the process of preparing mixed resin in step S1 is cancelled, and the polybutylene terephthalate is directly added to the original step S2.

[0069] Comparative example 3

[0070] The difference from example 2 is that the preparation process of step S2 is modified, and the mixed resin prepared in step S1 is directly mixed with the auxiliary agent and extruded and granulated.

[0071] Comparative example 4

[0072] The difference from example 2 is that the preparation process of the protective agent cancels step A1, and the material A is not added in step A5.

[0073] Comparative example 5

[0074] The difference from Example 2 is that the preparation process of the protective agent cancels the modified preparation of cellulose nanofibrils in step A1, and directly adds unmodified cellulose nanofibrils in step A5.

[0075] Comparative Example 6

[0076] The difference from Example 2 is that the preparation process of the protective agent cancels step A3, and directly adds unmodified 4-heptyloxybenzoic acid in step A4.

[0077] Performance test

[0078] Test Example 1: Stress Cracking Resistance Performance Test

[0079] The plastic bottle caps prepared from Examples 1-3 and Comparative Examples 1-6 are measured for tensile strength according to the standard BS EN ISO 527-1:2019. After bending to generate internal stress, 0.5 mL of glacial acetic acid is added to the bent part of the sample, and the sample is allowed to crack due to the erosion of glacial acetic acid. The cracking time is recorded, and the test results are shown in Table 1 below.

[0080] Test Example 2: Corrosion Resistance Test

[0081] The plastic bottle caps prepared from Examples 1-3 and Comparative Examples 1-6 are immersed in a mixture of ethanol and ethyl acetate with a volume ratio of 3:1 at room temperature for 60 days. The surface is observed for cracks, bubbles, oxidation and cracking. If there are any, it is unqualified, otherwise it is qualified. The qualified rate of 50 samples in each group is recorded in Table 1.

[0082] Table 1

[0083]

[0084] As can be seen from Table 1, the plastic bottle caps prepared from Examples 1-3 have good corrosion resistance; the lack of combination between polyethylene terephthalate, polybutylene terephthalate and the compatibilizer in Comparative Examples 1-3 leads to reduced chemical corrosion resistance; the absence of cellulose nanofibrils in Comparative Example 4 leads to reduced corrosion resistance; the absence of modification of cellulose nanofibrils in Comparative Example 5 leads to reduced crosslinking degree and reduced chemical corrosion resistance; the absence of grafting of nano-alumina on 4-heptyloxybenzoic acid in Comparative Example 6 leads to reduced chemical corrosion resistance.

[0085] The above merely describes the preferred embodiments of the present application, and is not intended to limit the present application in any form. Although the present application has been disclosed with the preferred embodiments as above, it is not intended to limit the present application. Any person skilled in the art can make some changes or modifications to the above disclosed technical content to obtain equivalent embodiments with equivalent changes, as long as the changes or modifications do not deviate from the technical solution of the present application. Any modification, change, equivalent change and modification of the above embodiments made according to the technical essence of the present application still belong to the scope of the technical solution of the present application.

Claims

1. A method for preparing a chemical resistant plastic bottle cap, characterized by, The preparation method of the plastic bottle cap comprises the following steps: S1, taking polyethylene terephthalate, polybutylene terephthalate, styrene-acrylonitrile-glycidyl methacrylate copolymer, extruding and granulating, water cooling and drawing and cutting, to obtain mixed resin; S2, taking acrylonitrile-butadiene-styrene copolymer, mixed resin, styrene-ethylene-butylene-styrene block copolymer, polypropylene, and additives, discharging, extruding and granulating, water cooling and drawing and cutting, mixing the granulated resin and foaming agent uniformly, and then putting into an injection molding machine to injection molding, to obtain a preform; S3, coating the surface of the preform with a protective agent and curing, to obtain the plastic bottle cap; The protective agent is a nanocellulose / epoxy acrylate graft copolymer mixture.

2. A process for the preparation of a chemical resistant plastic bottle cap as claimed in claim 1, wherein, In step S1, the mass ratio of polyethylene terephthalate, polybutylene terephthalate, and styrene-acrylonitrile-glycidyl methacrylate copolymer is 1.5-3.5:2-4:0.11-0.

22.

3. A process for preparing a chemical resistant plastic bottle cap as claimed in claim 1, wherein, In step S2, the mass ratio of acrylonitrile-butadiene-styrene copolymer, mixed resin, styrene-ethylene-butylene-styrene block copolymer, polypropylene, additives, and foaming agent is 3-5:5-7:2.5-2.8:78-82:0.8-1.2:1.5-2.

4. The method for preparing a chemical-resistant plastic bottle cap according to claim 1, characterized in that, The additives include ethylene bis-stearamide, magnesium stearate, antioxidant B215, polyethylene wax, nucleating agent NA-21, wollastonite, and ammonium polyphosphate.

5. The method for preparing a chemical-resistant plastic bottle cap according to claim 4, characterized in that, The mass ratio of ethylene bis-stearamide, magnesium stearate, antioxidant B215, polyethylene wax, nucleating agent NA-21, wollastonite, and ammonium polyphosphate is 3-4:1-2:1-3:1-3:1-2:1-2:1-2.

6. The method for preparing a chemical-resistant plastic bottle cap according to claim 1, characterized in that, The preparation method of the protective agent comprises the following steps: A1, taking silane coupling agent KH550, anhydrous ethanol, and deionized water, adjusting the pH to 3-5, heating and stirring, adding cellulose nanofilament, ultrasonic dispersion, transferring to a high-pressure hydrothermal kettle, sealing at 120℃ and 1MPa for 2-3h, taking out the mixed solution after the reaction, to obtain material A; the dosing ratio of silane coupling agent KH550, anhydrous ethanol, deionized water, and cellulose nanofilament is 1-1.2g:70-75mL:8-10mL:3-4g; A2, taking emulsifier SE-10N and deionized water, heating and stirring in a water bath, adding epoxy acrylate, and then continuing to stir, to obtain material B; the mass ratio of SE-10N, deionized water, and epoxy acrylate is 1-1.2:20-30:8-10; A3, taking tetrahydrofuran, 4-heptyloxybenzoic acid, and nano-alumina, ultrasonic dispersion, heating and stirring in a water bath under nitrogen atmosphere, centrifugal separation, drying the solid phase, to obtain modified aromatic hydrocarbon monomer; the dosing ratio of tetrahydrofuran, 4-heptyloxybenzoic acid, and nano-alumina is 50mL:1.5-1.8g:1-1.2g; A4. Take emulsifier SE-10N and deionized water, mix them, add modified aromatic hydrocarbon monomer under water bath heating and stirring conditions, and continue stirring after the addition is completed to obtain material C; the mass ratio of SE-10N, deionized water and modified aromatic hydrocarbon monomer is 1-1.2:20-30:10-12. A5. In a nitrogen atmosphere, mix material B, acrylamide, and acrylic acid, heat and stir in a 60°C water bath, add sodium thiosulfate, ammonium persulfate, and material C, keep warm and stir at 70°C, add material A, and continue to keep warm and stir to obtain material D; the mass ratio of material B, acrylamide, acrylic acid, sodium thiosulfate, ammonium persulfate, and material C is 12-16:4-6:1-3:0.6-0.8:0.4-0.6:8-10; A6. Take the aforementioned material D, deionized water, dispersant, defoamer, wetting agent, propylene glycol, precipitated barium sulfate, alcohol ester twelve, thickener, and water-based amine curing agent and mix them to obtain the protective agent; the mass ratio of the aforementioned material D, deionized water, dispersant, defoamer, wetting agent, propylene glycol, precipitated barium sulfate, alcohol ester twelve, thickener, and water-based amine curing agent is 50-60: 20-30: 0.4-0.6: 0.2-0.3: 0.1-0.2: 0.1-0.3: 0.1-0.3: 0.2-0.3: 0.1-0.2: 0.1-0.

2.

7. A chemical-resistant plastic bottle cap prepared by the method according to any one of claims 1-6.

8. Use of the chemical resistant plastic bottle cap according to claim 7 in cosmetic packaging, characterized by, The application refers to using the plastic bottle cap to seal cosmetics.

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