Anti-aging decorative frame for car lamp and preparation method of anti-aging decorative frame

Abstract

The invention discloses an anti-aging decorative frame for a car lamp and a preparation method of the anti-aging decorative frame, and relates to the technical field of car lamp decorative rings. Plating a metal film to form the metal film; applying a protective film to form the protective film; the matrix comprises PC, ABS, PBT, a compatibilizer, a filler, an antioxidant and a transesterification inhibitor; aBS is modified by an alkenyl compound and methyl methacrylate; the alkenyl compound is prepared from diisocyanate, 2-(4-aminophenyl)-5-benzotriazole amine and hydroxyethyl acrylate. According to the invention, polycarbonate, acrylonitrile-butadiene-styrene and polybutylene terephthalate are compounded to form a matrix high polymer material system, so that the matrix high polymer material system has excellent mechanical properties, processability, thermal stability and chemical stability. ABS is modified, so that the compatibility of a system is improved, the mechanical property, ultraviolet resistance and heat resistance of a matrix are improved, and the surface quality of the matrix is improved.

Description

Technical Field

[0001] The invention relates to the technical field of vehicle lamp bezels, in particular to an anti-aging decorative frame for a vehicle lamp and a preparation method thereof. Background Art

[0002] With the development of automobiles towards lightweight, polymer materials are increasingly used in automobiles. As a functional exterior trim, automobile headlight bezels have become an important part of personalized automobile design. Most headlight bezels are aluminum-plated. Due to the poor adhesion between the substrate and the aluminum layer of the headlight bezel, and the large difference in expansion and absorption, the aluminum film will break during use; and the gloss of the aluminum film produced by direct aluminum plating on the substrate surface is very poor. Therefore, a layer of primer is generally applied to the substrate surface before aluminum plating. However, the volatilization of the primer solvent will cause environmental pollution, the process is complicated, the cost cycle and recycling difficulty increase, and the design freedom is limited. In the structure of primer-free headlight bezels, there is a lack of isolation between the substrate and the aluminum film. Under long-term use or under the influence of heat, small molecules in the substrate will migrate, affecting the quality of the aluminum film. Therefore, we propose an aging-resistant decorative frame for headlights and a preparation method thereof. Summary of the invention

[0003] The object of the present invention is to provide an anti-aging decorative frame for a vehicle lamp and a preparation method thereof, so as to solve the problems raised in the above-mentioned background technology.

[0004] In order to solve the above technical problems, the present invention provides the following technical solutions: an anti-aging decorative frame for a vehicle lamp, comprising the following structures from the inside to the outside: a substrate, a metal film and a protective film.

[0005] Furthermore, the matrix is ​​a polymer material, specifically a mixture of one or more of polycarbonate (PC), acrylonitrile-butadiene-styrene (ABS), polymethyl methacrylate (PMMA), polybenzothiazole (PBT), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyimide (PI), and thermosetting plastic (BMC).

[0006] Furthermore, the thickness of the metal film is 200 nm to 10 μm.

[0007] Furthermore, the protective film is a combination of one or more of metal oxides, non-metal oxides, and organic silicon.

[0008] Furthermore, the thickness of the protective film is 80 nm to 2.5 μm.

[0009] A method for preparing an anti-aging decorative frame for a vehicle lamp comprises injection molding, plating a metal film and applying a protective film, and sequentially forming a substrate, a metal film and a protective film.

[0010] Furthermore, the matrix includes the following components by mass: 50-70 parts of PC, 30-40 parts of ABS, 5-20 parts of PBT, 0-10 parts of compatibilizer, 0.3-1.0 parts of filler, 0.2-2.0 parts of antioxidant, and 0-2.0 parts of ester exchange inhibitor.

[0011] In the above technical solution, polycarbonate (PC) contains carbonate groups in its molecular chain, has excellent mechanical properties, has good bonding strength with metal films, and can be directly aluminum-plated. Adding acrylonitrile-butadiene-styrene (ABS) in combination with PC can reduce the internal stress of the prepared matrix and reduce the sensitivity of the matrix to notches; it can also reduce the viscosity of the PC melt, improve the processing performance of the polymer material system, and improve the comprehensive performance of the prepared matrix. Polybutylene terephthalate (PBT) has good self-lubricity, thermal stability and chemical stability, and has high rigidity and hardness, good impact resistance, dimensional stability and heat resistance, which can further improve the comprehensive performance of the prepared matrix, such as mechanical properties, processing properties and heat resistance.

[0012] Furthermore, the compatibilizer is one of maleic anhydride grafted ABS, maleic anhydride-styrene copolymer (SMA), and methyl methacrylate-butadiene-styrene copolymer (MBS).

[0013] In the above technical solution, the compatibilizer can improve the compatibility between PC, PBT and ABS to a certain extent, so that the respective properties of the composite material made of the three can be fully exerted, thereby improving the comprehensive performance of the prepared matrix.

[0014] Furthermore, the filler is a mixture of one or more of carbon fiber, glass fiber, aluminosilicate, barium sulfate, silicon dioxide, and aluminum oxide.

[0015] In the above technical solution, adding fillers to polymer materials can improve the mechanical properties and processing properties of the matrix; and can play the role of nucleating agent to improve the crystallinity of the material, thereby further improving the heat resistance of the matrix. Aluminosilicates with mesoporous structures can absorb small molecules and reduce their volatility, which helps to improve the quality of aluminum films.

[0016] Furthermore, the antioxidant is one of Irganox 245 and Irganox 168, or a mixture of the two.

[0017] Furthermore, the transesterification inhibitor is a mixture of one or more of sodium dihydrogen phosphate, triphenyl phosphite, sodium hexametaphosphate, and sodium pyrophosphate.

[0018] In the above technical solution, the addition of the ester exchange inhibitor reduces the occurrence of ester exchange reaction in the polymer material system and prevents the regularity of the PET molecular chain from being destroyed; under the action of the ester exchange inhibitor, the ester exchange reaction mainly generates long-chain block copolymers, which improves the compatibility of the polymer material blending system to a certain extent, and improves the crystallinity, interface bonding and thermal stability of the polymer material system. However, the use of the above ester exchange inhibitor will produce small molecular volatiles, causing the aluminum film surface to be dull, colorful, foggy, etc.

[0019] Furthermore, ABS is modified, and the specific process is as follows: ABS and an initiator are mixed, and olefinic compounds and methyl methacrylate are added, and melt extrusion is performed, and the extruder temperature is 140-220° C. and the die temperature is 195-205° C.; and drying is performed to obtain modified ABS.

[0020] Further, the modified ABS includes the following components by mass: 100 parts of ABS, 4 to 15 parts of olefinic compounds, 15 to 30 parts of methyl methacrylate, and 0.3 to 0.5 parts of initiator; The initiator is dicumyl peroxide.

[0021] In the above technical solution, methyl methacrylate (MMA) has a higher molecular polarity, and its polarity and solubility parameters are close to those of PC. Compared with adding a compatibilizer, directly adding MMA to ABS by grafting is conducive to improving the interfacial bonding force, making the prepared modified ABS easier to disperse in PC and PBT, with stronger interfacial bonding force, and improving the impact strength of the polymer material system.

[0022] Further, the alkenyl compound is prepared by the following process: S1. Under a nitrogen atmosphere, diisocyanate and 3-methyl-1-phenylphosphine-1-oxide are mixed, the temperature is raised to 160-165° C., and the reaction is performed for 10-20 hours to obtain isocyanate carbonate diimide; S2. Mix 2-(4-aminophenyl)-5-benzotriazolamine, carbon disulfide, triethylamine and potassium carbonate in deionized water and stir for 100 to 150 minutes; heat to 94 to 98°C and reflux the reaction solution for 12 hours; cool, filter and dry to obtain a thiourea compound; The thiourea compound and polyethylene glycol are mixed in toluene, heated to 70-75°C, sodium hypochlorite is added, and the reaction is carried out for 90-120 minutes; sodium hydroxide is added, the temperature is raised to 80-90°C, and the reaction is carried out for 60-90 minutes; washing, rotary evaporation, and crystallization are performed to obtain phenyltriazole diamine; S3. Mix isocyanate carbonate diimide and phenyltriazolyl diamine, heat to 20-50°C, add a catalyst, and react for 10-30 minutes; add hydroxyethyl acrylate, heat to 80-85°C, and react for 10-30 minutes to obtain an olefinic compound.

[0023] Furthermore, in S1, the diisocyanate is one of cyclohexane-1,4-diisocyanate, 1,5-naphthalene diisocyanate, 4,4-diisocyanate dicyclohexylmethane, dimethylbiphenyl diisocyanate, isophorone diisocyanate, toluene diisocyanate dimer (CAS No.: 26747-90-0), and 4,4ˊ,4〞-triphenylmethane triisocyanate; The amount of 3-methyl-1-phenylphosphopentene-1-oxide used is 0.2% to 0.3% of the mass of diisocyanate.

[0024] Furthermore, in S2, the mass ratio of 2-(4-aminophenyl)-5-benzotriazolamine (CAS No.: 23851-59-4), carbon disulfide, triethylamine, and potassium carbonate is 10: (4.0-4.2): (0.5-0.6): (5.1-5.5); The ratio of 2-(4-aminophenyl)-5-benzotriazolamine to deionized water is (15-25) g / 100 mL.

[0025] Furthermore, in S2, the polyethylene glycol is PEG400; The mass ratio of thiourea compound, sodium hypochlorite, polyethylene glycol and sodium hydroxide is 100: (20.3-21.3): (11.4-12.0): (7.6-8.0); The ratio of thiourea compound to toluene is (20-25) g / 100 mL; Sodium hypochlorite is added in the form of an aqueous solution with a mass concentration of 6% to 8%; Sodium hydroxide was added in the form of an aqueous solution at a concentration of 1M.

[0026] Furthermore, in S3, the catalyst is dibutyltin dilaurate; The mass ratio of isocyanate carbonate diimide, phenyltriazolyl diamine, hydroxyethyl acrylate and catalyst is 100: (30-40): (1.5-5.0): (0.1-0.3).

[0027] In the above technical scheme, the modified ABS component also contains an olefinic compound, which is obtained by the reaction of isocyanate carbonate diimide, phenyltriazolyl diamine and hydroxyethyl acrylate. The isocyanate reacts with the amino group and the hydroxyl group to form a polyurethane structure. The polyurethane structure is introduced into the ABS system, which can effectively improve the processing performance of the polymer material system, improve its fluidity during the injection molding process, reduce molding defects, and improve the quality of the matrix; and can improve the mechanical properties of the polymer material system, so that the matrix exhibits better durability, thermal stability and impact resistance, and has a higher pyrolysis temperature; the compatibility between polymer material systems is also improved, and the bonding between the matrix and the metal film (aluminum film) can also be improved.

[0028] Under the action of 3-methyl-1-phenylphosphine-1-oxide, diisocyanate undergoes polycondensation reaction to generate carbodiimide to obtain isocyanate carbonate diimide. In a water dispersion system, 2-(4-aminophenyl)-5-benzotriazolamine reacts with carbon disulfide with triethylamine as a catalyst to form thiourea to obtain a thiourea compound; under the action of polyethylene glycol, it is oxidized with sodium hypochlorite to form carbodiimide to obtain phenyltriazolyl diamine. The reaction components of the two alkenyl compounds contain carbodiimide, which can effectively eliminate the carboxyl groups generated during the processing, thereby inhibiting the hydrolysis of polymer materials, reducing the generation of small molecular volatiles, and effectively maintaining the performance of the prepared matrix during production and use, and extending the service life of the product.

[0029] At the same time, the alkenyl compounds made from isocyanate carbonate diimide, phenyltriazolyl diamine and hydroxyethyl acrylate introduce benzotriazole, alicyclic or aromatic structures into the polymer material system, which improves the mechanical properties, UV resistance and high temperature resistance of the matrix, and improves the bonding with the metal film (aluminum film); and there are fewer small molecule products and lower volatiles, which, in conjunction with its high heat resistance, enables it to have the ability to be primed, and the quality of the metal film (aluminum film) is good.

[0030] Furthermore, the injection molding process is as follows: the temperatures of the first to fifth sections of the barrel are 220-230°C, 240-250°C, 240-250°C, 235-245°C, 225-235°C respectively, and the injection molding pressures are 45-55MPa, 45-55MPa, 60-70MPa, 70-80MPa respectively; the mold temperature is 215-225°C.

[0031] Furthermore, before injection molding, the raw material is placed at a temperature of 90 to 130° C. and dried for 2 to 4 hours.

[0032] Furthermore, the substrate is subjected to plasma treatment before metal film coating to activate the substrate surface, and the process conditions are as follows: voltage 1000-1500V, duration 3-5min; discharge gas is one of oxygen and argon or a mixture of the two, and the gas flow rate is 50-300sccm.

[0033] Furthermore, the metallized film is vacuum evaporation aluminum, and the process conditions are as follows: vacuum degree 0.5×10 -2 ~5.0×10 -2 Pa, duration 15 to 30 seconds, voltage 35 to 50V.

[0034] Furthermore, the upper protective film is plasma deposited with hexamethyldisiloxane, and the process conditions are as follows: vacuum degree 0.5×10 -2 ~5.0×10 -2 Pa, duration 6 to 10 minutes, voltage 1200 to 3000V.

[0035] Furthermore, after the protective film is applied, the protective film is subjected to plasma treatment, and the specific process conditions are as follows: voltage 1200-1800V, duration 20-50s, discharge gas is oxygen or a mixture of oxygen and argon, and gas flow rate is 50-300sccm. DETAILED DESCRIPTION

[0036] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] In the following specific embodiments, the "parts" are all parts by mass; ABS: Brand No. 0215A, from Jilin Petrochemical Co., Ltd.; PC: Brand 2805, from Bayer, Germany; PBT: Brand BM434, from Zhejiang Yizheng Chemical Fiber Engineering Plastics; The filler is a mixture of glass fiber and aluminosilicate, with a mass ratio of 1:2; Glass fiber: Adamas, aspect ratio 6mm / 15μm, from Shanghai Titan Technology Co., Ltd.; Aluminosilicate: surface area 900-1100m 2 / g, from Shanghai McLean; Polyethylene glycol: PEG400, from Nanjing Yingguan New Material Technology Co., Ltd.; The compatibilizer was maleic anhydride-styrene copolymer (SMA) Mn3800, sourced from Shanghai MacLean; The antioxidant is a mixture of Irganox245 and Irganox168, with a mass ratio of 1:1; The transesterification inhibitor is a mixture of triphenyl phosphite and sodium hexametaphosphate in a mass ratio of 1:1.

[0038] Embodiment 1: A method for preparing an anti-aging decorative frame for a vehicle lamp, comprising the following steps: Step 1: Preparation of modified ABS: S1. Under nitrogen atmosphere, isophorone diisocyanate and 0.2% 3-methyl-1-phenylphosphine-1-oxide were mixed, heated to 160°C, and reacted for 10 hours to obtain isocyanate carbonate diimide; S2. Mix 2-(4-aminophenyl)-5-benzotriazolamine, carbon disulfide, triethylamine and potassium carbonate in deionized water and stir for 100 min; heat to 94°C and reflux the reaction solution for 12 h; cool, filter and dry to obtain a thiourea compound; the mass ratio of 2-(4-aminophenyl)-5-benzotriazolamine, carbon disulfide, triethylamine and potassium carbonate is 10:4.0:0.5:5.1; the ratio of 2-(4-aminophenyl)-5-benzotriazolamine and deionized water is 15 g / 100 mL; The thiourea compound and polyethylene glycol are mixed in toluene, heated to 68°C, and 8wt% sodium hypochlorite aqueous solution is added, and the reaction is carried out for 90 minutes; 1M sodium hydroxide aqueous solution is added, and the temperature is raised to 80°C, and the reaction is carried out for 60 minutes; washing, rotary evaporation, and crystallization are performed to obtain phenyltriazolyl diamine; the mass ratio of the thiourea compound, sodium hypochlorite, polyethylene glycol, and sodium hydroxide is 100:20.3:11.4:7.6; the ratio of the thiourea compound to toluene is 20g / 100mL; S3. The isocyanate carbonate diimide and phenylpropanetriazole diamine were mixed, the temperature was raised to 20 ° C, a catalyst dibutyltin dilaurate was added, and the reaction was carried out for 30 min; hydroxyethyl acrylate was added, the temperature was raised to 80 ° C, and the reaction was carried out for 30 min to obtain an olefinic compound; the mass ratio of isocyanate carbonate diimide, phenylpropanetriazole diamine, hydroxyethyl acrylate, and the catalyst was 100:30:1.5:0.1; S4. Mix ABS and an initiator, add an olefinic compound and methyl methacrylate, melt extrude, the extruder temperature is 140 to 220°C, and the die temperature is 195°C; dry to obtain modified ABS; the modified ABS comprises the following mass components: 100 parts of ABS, 4 parts of an olefinic compound, 30 parts of methyl methacrylate, and 0.3 parts of an initiator diisopropylbenzene peroxide; Step 2, injection molding: 70 parts of PC, 30 parts of modified ABS, 5 parts of PBT, 0.3 parts of filler, and 0.2 parts of antioxidant are mixed and injection molded. The process is: the temperature of the first to fifth sections of the barrel is 230°C, 250°C, 250°C, 245°C, and 235°C, respectively, and the injection pressure is 55MPa, 55MPa, 70MPa, and 80MPa, respectively; the mold temperature is 225°C to form a matrix; Step 3: Metallization: Plasma treatment, the process is: voltage 1000V, duration 3min; discharge gas is oxygen, gas flow rate 50sccm; Vacuum evaporation aluminum plating, the process conditions are as follows: vacuum degree 0.5×10 -2 Pa, duration 30s, voltage 35V, forming a base metal film; Step 4: Upper protective film: plasma deposition of hexamethyldisiloxane, process: vacuum degree 0.5×10 -2 Pa, duration 10min, voltage 1200V; The protective film is subjected to plasma treatment, and the specific process conditions are as follows: voltage 1200 V, duration 50 s, discharge gas is oxygen, gas flow rate 50 sccm, to form a protective film.

[0039] Embodiment 2: A method for preparing an anti-aging decorative frame for a vehicle lamp, comprising the following steps: Step 1: Preparation of modified ABS: S1. Under nitrogen atmosphere, 4,4-diisocyanate dicyclohexylmethane and 0.25% 3-methyl-1-phenylphosphine-1-oxide were mixed, heated to 162°C, and reacted for 15h to obtain isocyanate carbonate diimide; S2. Mix 2-(4-aminophenyl)-5-benzotriazolamine, carbon disulfide, triethylamine and potassium carbonate in deionized water and stir for 120 min; heat to 95°C and reflux the reaction solution for 12 h; cool, filter and dry to obtain a thiourea compound; the mass ratio of 2-(4-aminophenyl)-5-benzotriazolamine, carbon disulfide, triethylamine and potassium carbonate is 10:4.1:0.55:5.3; the ratio of 2-(4-aminophenyl)-5-benzotriazolamine and deionized water is 20 g / 100 mL; The thiourea compound and polyethylene glycol are mixed in toluene, heated to 70°C, and a 7wt% sodium hypochlorite aqueous solution is added, and the reaction is carried out for 105 minutes; a 1M sodium hydroxide aqueous solution is added, and the temperature is raised to 85°C, and the reaction is carried out for 75 minutes; washing, rotary evaporation, and crystallization are performed to obtain phenyltriazolyl diamine; the mass ratio of the thiourea compound, sodium hypochlorite, polyethylene glycol, and sodium hydroxide is 100:20.8:11.7:7.8; the ratio of the thiourea compound to toluene is 22g / 100mL; S3. The isocyanate carbonate diimide and phenylpropanetriazole diamine were mixed, the temperature was raised to 35 ° C, a catalyst dibutyltin dilaurate was added, and the reaction was carried out for 20 min; hydroxyethyl acrylate was added, the temperature was raised to 82 ° C, and the reaction was carried out for 20 min to obtain an olefinic compound; the mass ratio of isocyanate carbonate diimide, phenylpropanetriazole diamine, hydroxyethyl acrylate, and the catalyst was 100:35:3.3:0.2; S4. Mix ABS and an initiator, add an olefinic compound and methyl methacrylate, melt extrude, the extruder temperature is 140 to 220°C, and the die temperature is 200°C; dry to obtain modified ABS; the modified ABS comprises the following mass components: 100 parts of ABS, 10 parts of an olefinic compound, 24 parts of methyl methacrylate, and 0.4 parts of an initiator diisopropylbenzene peroxide; Step 2, injection molding: 60 parts of PC, 35 parts of modified ABS, 12 parts of PBT, 0.6 parts of filler, and 1.0 parts of antioxidant are mixed and injection molded. The process is: the temperature of the first to fifth sections of the barrel is 225°C, 245°C, 245°C, 240°C, and 230°C, respectively, and the injection pressure is 50MPa, 50MPa, 65MPa, and 75MPa, respectively; the mold temperature is 220°C to form a matrix; Step 3: Metallization: Plasma treatment, the process is: voltage 1200V, duration 4min; discharge gas is a mixture of oxygen and argon, the total gas flow rate is 150sccm, the ratio is 1:1; Vacuum evaporation aluminum plating, the process conditions are as follows: vacuum degree 2.5×10 -2 Pa, duration 20s, voltage 45V, forming a base metal film; Step 4: Upper protective film: plasma deposition of hexamethyldisiloxane, process: vacuum degree 2.5×10 -2 Pa, duration 8min, voltage 2000V; The protective film is subjected to plasma treatment, and the specific process conditions are as follows: voltage 1500V, duration 35s, discharge gas is a mixture of oxygen and argon, total gas flow rate 150sccm, ratio 1:1, to form a protective film.

[0040] Embodiment 3: A method for preparing an anti-aging decorative frame for a vehicle lamp, comprising the following steps: Step 1: Preparation of modified ABS: S1. Under nitrogen atmosphere, 4,4ˊ,4〞-triphenylmethane triisocyanate and 0.3% 3-methyl-1-phenylphosphine-1-oxide were mixed, heated to 165°C, and reacted for 20h to obtain isocyanate carbonate diimide; S2. Mix 2-(4-aminophenyl)-5-benzotriazolamine, carbon disulfide, triethylamine and potassium carbonate in deionized water and stir for 150 min; heat to 98°C and reflux the reaction solution for 12 h; cool, filter and dry to obtain a thiourea compound; the mass ratio of 2-(4-aminophenyl)-5-benzotriazolamine, carbon disulfide, triethylamine and potassium carbonate is 10:4.2:0.6:5.5; the ratio of 2-(4-aminophenyl)-5-benzotriazolamine and deionized water is 25 g / 100 mL; The thiourea compound and polyethylene glycol are mixed in toluene, heated to 72°C, and a 6wt% sodium hypochlorite aqueous solution is added, and the reaction is carried out for 120 minutes; a 1M sodium hydroxide aqueous solution is added, and the temperature is raised to 90°C, and the reaction is carried out for 90 minutes; washing, rotary evaporation, and crystallization are performed to obtain phenyltriazolyl diamine; the mass ratio of the thiourea compound, sodium hypochlorite, polyethylene glycol, and sodium hydroxide is 100:21.3:12.0:8.0; the ratio of the thiourea compound to toluene is 25g / 100mL; S3. The isocyanate carbonate diimide and phenylpropanetriazole diamine were mixed, the temperature was raised to 50 ° C, a catalyst dibutyltin dilaurate was added, and the reaction was carried out for 10 min; hydroxyethyl acrylate was added, the temperature was raised to 85 ° C, and the reaction was carried out for 10 min to obtain an olefinic compound; the mass ratio of isocyanate carbonate diimide, phenylpropanetriazole diamine, hydroxyethyl acrylate, and the catalyst was 100:40:5.0:0.3; S4. Mix ABS and an initiator, add an olefinic compound and methyl methacrylate, melt extrude, the extruder temperature is 140 to 220°C, and the die temperature is 205°C; dry to obtain modified ABS; the modified ABS comprises the following mass components: 100 parts of ABS, 15 parts of an olefinic compound, 20 parts of methyl methacrylate, and 0.5 parts of an initiator diisopropylbenzene peroxide; Step 2, injection molding: 50 parts of PC, 40 parts of modified ABS, 20 parts of PBT, 1.0 part of filler, and 2.0 parts of antioxidant are mixed and injection molded. The process is: the temperature of the first to fifth sections of the barrel is 220°C, 240°C, 240°C, 235°C, and 225°C, respectively, and the injection pressure is 45MPa, 45MPa, 60MPa, and 70MPa, respectively; the mold temperature is 215°C to form a matrix; Step 3: Metallization: Plasma treatment, the process is: voltage 1500V, duration 5min; discharge gas is a mixture of oxygen and argon, the total gas flow rate is 300sccm, the ratio is 1:5; Vacuum evaporation aluminum plating, the process conditions are as follows: vacuum degree 5.0×10 -2 Pa, duration 15s, voltage 50V, forming a base metal film; Step 4: Upper protective film: plasma deposition of hexamethyldisiloxane, process: vacuum degree 5.0×10 -2 Pa, duration 6min, voltage 3000V; The protective film is subjected to plasma treatment, and the specific process conditions are as follows: voltage 1800V, duration 20s, discharge gas is a mixture of oxygen and argon, total gas flow rate 300sccm, ratio 1:5, to form a protective film.

[0041] Comparative Example 1: A method for preparing an anti-aging decorative frame for a vehicle lamp, comprising the following steps: Step 1: Preparation of modified ABS: Mix isophorone diisocyanate and 2-(4-aminophenyl)-5-benzotriazolamine, heat to 20°C, add dibutyltin dilaurate as a catalyst, and react for 30 minutes; add hydroxyethyl acrylate, heat to 80°C, and react for 30 minutes to obtain an olefin compound; the mass ratio of isophorone diisocyanate, 2-(4-aminophenyl)-5-benzotriazolamine, hydroxyethyl acrylate, and catalyst is 10:5.1:5.3:0.01; ABS and an initiator are mixed, and an olefinic compound and methyl methacrylate are added, and the mixture is melt-extruded, and the extruder temperature is 140-220° C. and the die head temperature is 195° C.; and the mixture is dried to obtain a modified ABS; the modified ABS comprises the following components by mass: 100 parts of ABS, 4 parts of an olefinic compound, 30 parts of methyl methacrylate, and 0.3 parts of an initiator, diisopropylbenzene peroxide; Steps 2-4 are the same as those in Example 1 to obtain a decorative frame.

[0042] Comparative Example 2: A method for preparing an anti-aging decorative frame for a vehicle lamp, comprising the following steps: Step 1: Preparation of modified ABS: ABS and an initiator are mixed, methyl methacrylate is added, and the mixture is melt-extruded at an extruder temperature of 140 to 220° C. and a die head temperature of 195° C.; and the mixture is dried to obtain a modified ABS; the modified ABS comprises the following components by mass: 100 parts of ABS, 30 parts of methyl methacrylate, and 0.3 parts of an initiator, diisopropylbenzene peroxide; Steps 2-4 are the same as those in Example 1 to obtain a decorative frame.

[0043] Comparative Example 3: A method for preparing an anti-aging decorative frame for a vehicle lamp, comprising the following steps: Step 1, injection molding: 70 parts of PC, 30 parts of ABS, 5 parts of PBT, 0.3 parts of filler, 5 parts of compatibilizer, 0.3 parts of filler, 0.2 parts of antioxidant, and 1 part of ester exchange inhibitor are mixed and injection molding is performed. The process is: the temperature of the first to fifth sections of the barrel is 230°C, 250°C, 250°C, 245°C, and 235°C, respectively, and the injection pressure is 55MPa, 55MPa, 70MPa, and 80MPa, respectively; the mold temperature is 225°C to form a matrix; Steps 2-3 are the same as steps 3-4 in Example 1 to obtain a decorative frame.

[0044] Experiment: Take the decorative frames obtained in Examples 1-3 and Comparative Examples 1-3, prepare samples, test their performances respectively and record the test results: Mechanical properties: GB / T 1040.1 was used as the reference standard to test the tensile strength of the matrix sample at a tensile rate of 10 mm / min. Using ATSM-D256 as the reference standard, the notched impact strength of the matrix sample was tested, with a notch depth of 2.54 mm and a pendulum of 2.8 J. Taking GB / T 9341 as reference standard, the bending performance of the base specimen was tested at a rate of 2 mm / min. Surface gloss: Use a gloss tester, use a high-mirror mold injection molding test specimen with a center line average roughness of 1.0nm, and the incident angle of light is 20°; Heat resistance temperature: Using ATSM-D648 as reference standard, the heat resistance temperature of the matrix sample is tested, the sample thickness is 6.4mm, and the load is 0.45MPa; Anti-ultraviolet performance: Place the substrate sample in a xenon lamp aging test box and age it for 500 hours. Test its tensile strength again and record its strength loss rate.

[0045]

[0046] According to the data in the above table, we can clearly draw the following conclusions: The decorative frames obtained in Examples 1-3 are compared with the decorative frames obtained in Comparative Examples 1-3. The test results show that: Compared with the comparative example, the tensile strength, bending strength and impact toughness data of the base of the decorative frame obtained in Examples 1-3 are higher, which shows that the base has higher mechanical properties; the surface gloss is higher, which can meet the application requirements of primer-free, which shows that the base injection molding system has good processing performance, strong replication ability on the mold surface, less formation of small molecule volatiles, and better surface morphology of the base; the heat-resistant temperature is higher, which shows that the heat resistance of the base is improved, less pyrolysis occurs during processing and use, which helps to reduce small molecule volatiles; the strength loss rate is lower, which shows that the anti-ultraviolet ability of the base is improved. This fully demonstrates that the present invention achieves the improvement of the mechanical properties, heat resistance and anti-ultraviolet ability of the base and the decorative frame, and achieves its primer-free and aging-resistant characteristics.

[0047] Compared with Example 1, the alkenyl compound in Comparative Example 1 is prepared from isophorone diisocyanate, 2-(4-aminophenyl)-5-benzotriazolamine, and hydroxyethyl acrylate; the modified ABS in Comparative Example 2 is prepared from ABS and methyl methacrylate; the ABS in Comparative Example 3 is not modified, and a compatibilizer and an ester exchange inhibitor are added. The polymer material degrades during processing, causing the acid value to increase, the mechanical properties to decrease, the molecules to be destroyed, and the degradation to accelerate. The performance of the matrix continues to decrease during storage and use, and the expected service life cannot be achieved; the ester exchange inhibitor decomposes small molecules, which is not conducive to the construction of the primer-free matrix. The decorative frames obtained in Comparative Examples 1-3 have deteriorated matrix tensile strength, bending strength and impact toughness data, surface gloss, heat resistance temperature and strength loss rate data. It can be seen that the setting of the matrix component and its process in this application can promote the comprehensive improvement of its mechanical properties, heat resistance and UV resistance.

[0048] PBAT is easily degraded during processing, resulting in an increase in acid value and melt index, and a decrease in mechanical properties, which has caused considerable problems in production [6-7]. In addition, in a humid and warm environment, the ester bonds in the molecular chain will be attacked by water molecules and destroyed, hydrolyzed and produce carboxyl groups, which will further accelerate the hydrolysis of the ester bonds, resulting in a decrease in the performance of the material during storage and use, and failing to achieve the expected service life.

[0049] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

Claims

1. A method for preparing an anti-aging decorative frame for a vehicle lamp, characterized in that: The process steps include: Injection molding to form a substrate; metallization to form a metal film; protective film application to form a protective film; The matrix comprises the following components by mass: 50-70 parts of PC, 30-40 parts of ABS, 5-20 parts of PBT, 0-10 parts of a compatibilizer, 0.3-1.0 parts of a filler, 0.2-2.0 parts of an antioxidant, and 0-2.0 parts of an ester exchange inhibitor; The ABS is modified, and the specific process is as follows: ABS and an initiator are mixed, an olefinic compound and methyl methacrylate are added, and melt extrusion is performed, the extruder temperature is 140-220°C, and the die temperature is 195-205°C to obtain modified ABS; the olefinic compound is prepared from diisocyanate, 2-(4-aminophenyl)-5-benzotriazolamine, and hydroxyethyl acrylate.

2. The method for preparing an anti-aging decorative frame for a vehicle lamp according to claim 1, characterized in that: The alkenyl compound is prepared by the following process: S1. Under a nitrogen atmosphere, diisocyanate and 3-methyl-1-phenylphosphine-1-oxide are mixed, the temperature is raised to 160-165° C., and the reaction is performed for 10-20 hours to obtain isocyanate carbonate diimide; S2. 2-(4-aminophenyl)-5-benzotriazolamine, carbon disulfide, triethylamine and potassium carbonate are mixed in deionized water and stirred for 100 to 150 minutes; the temperature is raised to 94 to 98° C. and the reaction solution is refluxed for 12 hours to obtain a thiourea compound; Mix the thiourea compound and polyethylene glycol in toluene, heat to 70-75°C, add sodium hypochlorite, and react for 90-120 minutes; add sodium hydroxide, heat to 80-90°C, and react for 60-90 minutes to obtain phenyltriazolyl diamine; S3. Mix isocyanate carbonate diimide and phenyltriazolyl diamine, heat to 20-50°C, add a catalyst, and react for 10-30 minutes; add hydroxyethyl acrylate, heat to 80-85°C, and react for 10-30 minutes to obtain an olefinic compound.

3. The method for preparing an anti-aging decorative frame for a vehicle lamp according to claim 1, characterized in that: The modified ABS comprises the following components by mass: 100 parts of ABS, 4 to 15 parts of olefinic compounds, 15 to 30 parts of methyl methacrylate, and 0.3 to 0.5 parts of initiator.

4. The method for preparing an anti-aging decorative frame for a vehicle lamp according to claim 2, characterized in that: In S1, the diisocyanate is one of cyclohexane-1,4-diisocyanate, 1,5-naphthalene diisocyanate, 4,4-diisocyanate dicyclohexylmethane, dimethylbiphenyl diisocyanate, isophorone diisocyanate, toluene diisocyanate dimer, and 4,4ˊ,4〞-triphenylmethane triisocyanate.

5. The method for preparing an anti-aging decorative frame for a vehicle lamp according to claim 2, characterized in that: In S2, the mass ratio of 2-(4-aminophenyl)-5-benzotriazolamine, carbon disulfide, triethylamine and potassium carbonate is 10:(4.0-4.2):(0.5-0.6):(5.1-5.5).

6. The method for preparing an anti-aging decorative frame for a vehicle lamp according to claim 3, characterized in that: In the S2, the mass ratio of the thiourea compound, sodium hypochlorite, polyethylene glycol, and sodium hydroxide is 100: (20.3-21.3): (11.4-12.0): (7.6-8.0).

7. The method for preparing an anti-aging decorative frame for a vehicle lamp according to claim 2, characterized in that: In the S3, the mass ratio of isocyanate carbonate diimide, phenyltriazolyl diamine and hydroxyethyl acrylate is 100: (30-40): (1.5-5.0).

8. The method for preparing an anti-aging decorative frame for a vehicle lamp according to claim 1, characterized in that: The process conditions of the injection molding are as follows: the temperatures of the first to fifth sections of the barrel are 220-230°C, 240-250°C, 240-250°C, 235-245°C, and 225-235°C, respectively; the injection pressures are 45-55MPa, 45-55MPa, 60-70MPa, and 70-80MPa, respectively; and the mold temperature is 215-225°C.

9. The method for preparing an anti-aging decorative frame for a vehicle lamp according to claim 1, characterized in that: The filler is a mixture of one or more of carbon fiber, glass fiber, aluminosilicate, barium sulfate, silicon dioxide and aluminum oxide.

10. An anti-aging decorative frame for a vehicle lamp prepared according to the preparation method according to any one of claims 1 to 9.

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