Preparation method of wear-resistant engineering plastic for camera shell
By blending PC and PEEK and modifying SiC composite fillers with graphene coating, combined with microencapsulated toughening agents and antioxidants, the problems of wear resistance, toughness and anti-aging of engineering plastics for camera housings have been solved, achieving the preparation of high-performance and economically feasible materials.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- WUHAN INST OF TECH
- Filing Date
- 2026-03-04
- Publication Date
- 2026-04-17
AI Technical Summary
Traditional engineering plastics used in camera housings are insufficient in terms of wear resistance, toughness, and anti-aging properties, and cannot effectively resist the wear and ultraviolet radiation of outdoor environments. Furthermore, the poor interfacial bonding between inorganic fillers and organic matrices leads to unstable material properties.
A synergistic matrix was constructed by blending PC and PEEK, modified by coating SiC composite filler with graphene, and combined with microencapsulated toughening agents, antioxidants, and lubricating dispersants. The resulting material was formed using gradient temperature-controlled melt blending and vacuum drying processes, resulting in a wear-resistant and tough material.
It significantly improves the wear resistance and anti-aging ability of the material, ensuring that the shell is not easily brittle in complex environments. The stability of the material performance is improved, meeting the high-performance requirements of camera shells, while reducing production costs and environmental friendliness.
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Figure CN121873522A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of engineering plastics preparation technology, and in particular to a method for preparing wear-resistant engineering plastics for camera housings. Background Technology
[0002] In the field of camera housing manufacturing, engineering plastics are widely used due to their excellent comprehensive properties. Traditional manufacturing techniques for engineering plastics used in camera housings met basic production needs for a certain period, providing essential material support for camera housing production. However, with the continuous expansion of camera applications, especially the increasing demand for use in complex environments such as outdoor settings, the performance requirements for engineering plastics used in camera housings are also rising, making traditional manufacturing techniques increasingly inadequate to meet these new development needs.
[0003] From a performance and manufacturing process perspective, traditional wear-resistant engineering plastics used for camera housings have several shortcomings. In terms of wear resistance, traditional materials may not effectively resist outdoor sand and gravel friction and daily scratches, leading to scratches on the housing after prolonged use, affecting aesthetics and protective performance. This may be due to insufficient hardness, lubricity, and dispersibility, preventing the formation of an effective wear-resistant system. Regarding toughness, some traditional materials, in pursuit of wear resistance, often result in excessively high rigidity and decreased toughness, making them prone to brittleness in complex environments, affecting the normal use of the camera. In terms of anti-aging performance, traditional materials, when used outdoors, are easily affected by factors such as ultraviolet radiation, leading to yellowing, brittleness, and other performance degradation. This is mainly due to unreasonable design of antioxidants and anti-aging systems. Furthermore, in terms of material preparation processes, traditional methods may not effectively improve the interfacial bonding between inorganic fillers and the organic matrix, leading to filler agglomeration and affecting the stability of material performance.
[0004] To address these issues, we provide a method for preparing wear-resistant engineering plastics for camera housings. Summary of the Invention
[0005] The purpose of this invention is to provide a method for preparing wear-resistant engineering plastics for camera housings. By constructing a synergistic matrix through PC and PEEK blending, secondary modification with composite fillers, and reasonable compounding of various additives, this method solves the problems of insufficient wear resistance in existing preparation methods, inability to effectively resist outdoor sand and gravel friction and daily scratches, easy scratching of the housing after long-term use, difficulty in balancing toughness and rigidity, easy cracking in complex environments, weak anti-aging ability, easy yellowing and brittleness leading to performance degradation during outdoor use, poor interfacial bonding between inorganic fillers and organic matrix, and easy agglomeration of fillers affecting the stability of material performance.
[0006] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution: This invention relates to a method for preparing wear-resistant engineering plastics for camera housings, comprising the following steps: Step a: Secondary modification of composite filler: First, graphene-coated SiC composite filler is modified and dried using a rare earth coupling agent ethanol solution, and then ball-milled and dried using a silane-titanium ester composite coupling agent to obtain a secondary modified composite filler; Step b: Staged premixing: Polycarbonate and polyether ketone ketone are premixed to obtain a blend matrix, and then the secondary modified composite filler, microencapsulated toughening agent, antioxidant compound system, anti-aging synergistic system, and lubricating dispersant EBS are added sequentially, and the premix is obtained through staged mixing; Step c: Gradient temperature-controlled melt blending extrusion: The premix is added to a twin-screw extruder, and subjected to gradient temperature-controlled extrusion, water cooling, pelletizing, and screening to obtain composite particles; Step d: Staged vacuum drying: The composite particles are subjected to two-stage vacuum drying to obtain the finished material.
[0007] The present invention is further configured such that, in step a, the purity of SiC in the graphene-coated SiC composite filler is ≥99.5%, and the graphene coating amount is 5-8wt%; the preparation method of the graphene-coated SiC composite filler is as follows: 100g of SiC powder with a particle size of 800-1200nm is dispersed in 500mL of deionized water and ultrasonically dispersed for 30min; 5g of graphene oxide is added, the pH is adjusted to 8-9, and the mixture is stirred at 80℃ for 2h; 10g of hydrazine hydrate is added, and the mixture is stirred for another 4h to reduce the graphene oxide to graphene; the mixture is filtered, washed until neutral, and dried at 120℃ for 6h to obtain the final product.
[0008] The present invention is further configured such that, in step a, the mass concentration of the rare earth coupling agent ethanol solution is 10%, and the rare earth coupling agent is lanthanum nitrate modified silane coupling agent KH550; the mixing speed for the first modification is 1200 r / min, the mixing time is 15 min, the drying temperature is 120℃, and the drying time is 3-4 h.
[0009] The present invention is further configured such that, in step a, the silane-titanium ester complex coupling agent is composed of silane coupling agent KH560 and titanate coupling agent NDZ-311 in a mass ratio of 1:0.8; the ball milling speed for secondary modification is 300 r / min, the ball milling time is 2 h, the drying temperature is 100 ℃, and the drying time is 2 h.
[0010] The present invention is further configured such that the weight parts of each raw material in step b are: 50-60 parts of polycarbonate, 15-20 parts of polyether ketone ketone, 8-15 parts of secondary modified composite filler, 6-10 parts of microencapsulated toughening agent, 0.8-1.2 parts of antioxidant compound system, 0.7-1.1 parts of anti-aging synergistic system, and 0.6-1.0 parts of EBS.
[0011] The present invention is further configured such that, in step b, the molecular weight of polycarbonate is 30,000-35,000 and the viscosity-average molecular weight of polyether ketone is 40,000-45,000; the specific parameters for the staged premixing are: the first stage is 800 r / min for 8 min, the second stage is 1000 r / min for 10 min, and the third stage is 1000 r / min for 5 min.
[0012] The present invention is further configured such that, in step b, the microcapsule toughening agent has a particle size of 5-10 μm, the core material is a composite system of POE-g-MAH and nano calcium carbonate, the total content of the core material is 60-70 wt%, the nano calcium carbonate accounts for 15-20% of the core material content, and the shell material is urea-formaldehyde resin.
[0013] The present invention is further configured such that, in step b, the antioxidant compound system is composed of antioxidant 1010, antioxidant 168 and antioxidant DLTP in a mass ratio of 1:1:0.5; and the anti-aging synergistic system is composed of ultraviolet absorber UV-327 and hindered amine light stabilizer GW-540 in a mass ratio of 2:1.
[0014] The present invention is further configured such that the gradient temperature of the twin-screw extruder in step c is: feed inlet 235-245℃, compression section 250-260℃, first melting section 265-275℃, second melting section 275-285℃, homogenization section 278-283℃, front of die head 272-278℃, die head 268-273℃; main extruder speed 400-450 r / min, feed speed 90-110 r / min, die head pressure 14-17 MPa; water cooling temperature 25-30℃, and composite material particle size 2-3 mm.
[0015] The present invention is further configured such that the parameters for the segmented vacuum drying in step d are: the first stage is drying at 80°C for 2 hours, and the second stage is drying at 130°C for 5 hours.
[0016] The present invention has the following beneficial effects: 1. This invention constructs a "toughness-wear resistance" synergistic matrix by blending PC and PEEK, and combines it with graphene-coated SiC composite filler to form a three-in-one reinforcement effect of "hardness-lubrication-dispersion", which greatly improves the wear resistance of the material, effectively resists outdoor sand and gravel friction and daily scratches, and can maintain the smoothness of the shell even after long-term use. The application of microencapsulated toughening agent improves the toughness of the material while avoiding the decrease in rigidity, ensuring that the material is not easy to crack in complex environments. The antioxidant compound system and ultraviolet absorber work synergistically to significantly enhance the anti-aging ability and avoid performance degradation such as yellowing and brittleness during outdoor use.
[0017] 2. This invention improves the interfacial bonding force between inorganic fillers and organic matrix through rare earth coupling agent modification, avoids filler agglomeration, ensures material performance stability, has clear and standardized process steps, requires no special equipment for twin-screw extrusion and injection molding, is easy to operate and controllable, has high molding precision, and can meet the processing requirements of complex camera housing structures. All raw materials used are commercially available environmentally friendly materials, and the preparation process has no waste discharge, which meets green production standards. The blending design of PC and PEEK effectively controls costs while ensuring high performance, taking into account performance advantages and economic feasibility, and the material has wide compatibility. Attached Figure Description
[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below.
[0019] Figure 1 This is a general flow chart of a method for preparing abrasion-resistant engineering plastic for camera housings.
[0020] Figure 2 This is a detailed, step-by-step flowchart of a method for preparing a wear-resistant engineering plastic for camera housings.
[0021] Figure 3 This is a tree-structured flowchart of a method for preparing abrasion-resistant engineering plastics for camera housings. Detailed Implementation
[0022] The technical solutions of the present invention will be described below with reference to the accompanying drawings. The described embodiments are only some embodiments of the present invention, and not all embodiments.
[0023] Example 1 Please refer to Figure 1-3A method for preparing wear-resistant engineering plastics for camera housings includes the following steps: Step a: Secondary modification of composite filler: First, graphene-coated SiC composite filler is modified and dried using a rare earth coupling agent ethanol solution, then modified and dried again using a silane-titanium ester composite coupling agent through ball milling, resulting in a secondary modified composite filler. The purity of SiC in the graphene-coated SiC composite filler is ≥99.5%, and the graphene coating amount is 5-8wt%. The preparation method of graphene-coated SiC composite filler is as follows: 100g of SiC powder with a particle size of 800-1200nm is dispersed in 500mL of deionized water and ultrasonically dispersed for 30min; 5g of graphene oxide is added. Graphene oxide was adjusted to pH 8-9 and reacted at 80℃ for 2 hours with stirring. 10g of hydrazine hydrate was added, and the reaction was continued with stirring for 4 hours to reduce graphene oxide to graphene. The graphene oxide was filtered, washed until neutral, and dried at 120℃ for 6 hours to obtain the desired product. The rare earth coupling agent ethanol solution had a mass concentration of 10%, and the rare earth coupling agent was lanthanum nitrate-modified silane coupling agent KH550. The primary modification involved mixing at 1200 r / min for 15 min, drying at 120℃ for 3-4 hours, and using a silane-titanium ester complex coupling agent composed of silane coupling agent KH560 and titanate coupling agent NDZ-311 at a mass ratio of 1:0.8. The secondary modification involved ball milling at 300 r / min for [missing information - likely a specific time range]. 2h, drying temperature 100℃, drying time 2h; Step b: staged premixing: first, premix polycarbonate and polyether ketone ketone to obtain a blend matrix, then add secondary modified composite filler, microencapsulated toughening agent in sequence, and finally add antioxidant compound system, anti-aging synergistic system, and lubricating dispersant EBS. Mix in stages to obtain a premix. The weight parts of each raw material are: polycarbonate 50-60 parts, polyether ketone ketone 15-20 parts, secondary modified composite filler 8-15 parts, microencapsulated toughening agent 6-10 parts, antioxidant compound system 0.8-1.2 parts, anti-aging synergistic system 0.7-1.1 parts, EBS 0.6-1.0 parts, and the molecular weight of polycarbonate is 30000-35 The viscosity-average molecular weight of polyether ketone is 40,000-45,000. The specific parameters for staged premixing are as follows: first stage: 800 r / min, 8 min; second stage: 1000 r / min, 10 min; third stage: 1000 r / min, 5 min. The microcapsule toughening agent has a particle size of 5-10 μm. The core material is a composite system of POE-g-MAH and nano-calcium carbonate, with a total core material content of 60-70 wt%, and nano-calcium carbonate accounting for 15-20% of the core material mass. The shell material is urea-formaldehyde resin. The antioxidant compound system consists of antioxidant 1010, antioxidant 168, and antioxidant DLTP in a mass ratio of 1:1:0.5. Composition; The anti-aging synergistic system is composed of UV absorber UV-327 and hindered amine light stabilizer GW-540 in a mass ratio of 2:1; Step c: Gradient temperature controlled melt blending extrusion: The premixed material is added to a twin-screw extruder, and after gradient temperature controlled extrusion, water cooling, pelletizing, and screening, composite particles are obtained. The gradient temperature of the twin-screw extruder is: feed inlet 235-245℃, compression section 250-260℃, first melting section 265-275℃, second melting section 275-285℃, homogenization section 2 Temperature ranges from 78-283℃, with the temperature before the die head at 272-278℃ and the die head at 268-273℃; main machine speed is 400-450 r / min, feeding speed is 90-110 r / min, and die head pressure is 14-17 MPa; water cooling temperature is 25-30℃, and the composite material particle size is 2-3 mm; Step d: Segmented vacuum drying: The composite material particles are dried in two stages to obtain the finished material. The parameters for segmented vacuum drying are: first stage drying at 80℃ for 2 hours, and second stage drying at 130℃ for 5 hours.
[0024] Example 2 A method for preparing wear-resistant engineering plastics for camera housings Secondary modification of composite fillers: (1) Add graphene-coated SiC composite filler to a high-speed mixer, spray with a 10% mass concentration of rare earth coupling agent ethanol solution (lanthanum nitrate modified silane coupling agent KH550), mix at 1200 r / min for 15 min, and dry at 120℃ for 3-4 h to obtain a primary modified filler. (2) The primary modified filler was added to a planetary ball mill, and a compound system of silane coupling agent KH560 and titanate coupling agent NDZ-311 (mass ratio 1:0.8) was added. The ball milling speed was 300 r / min and the ball milling time was 2 h. Then it was dried at 100℃ for 2 h to obtain the secondary modified composite filler. The graphene-coated SiC composite filler has a SiC purity ≥ 99.5% and a graphene coating amount of 5-8 wt%. The preparation method is as follows: 100g of SiC powder with a particle size of 800-1200nm is dispersed in 500mL of deionized water and ultrasonically dispersed for 30min; 5g of graphene oxide is added, the pH is adjusted to 8-9, and the mixture is stirred at 80℃ for 2h; 10g of hydrazine hydrate is added, and the mixture is stirred for another 4h to reduce the graphene oxide to graphene; the mixture is filtered, washed until neutral, and dried at 120℃ for 6h to obtain the final product.
[0025] Staged premixing: (1) First stage: Weigh 50-60 parts of polycarbonate (molecular weight 30000-35000) and 15-20 parts of polyether ketone ketone (PEEK, viscosity-average molecular weight 40000-45000) according to the weight, add them to a high-speed mixer, mix at 800r / min for 8min to obtain a uniform blend matrix; (2) Second stage: Add 8-15 parts of secondary modified composite filler and 6-10 parts of microcapsule toughening agent to the blend matrix in sequence, and mix at 1000r / min for 10min; the microcapsule toughening agent has a particle size of 5-10μm, the core material is a composite system of POE-g-MAH and nano calcium carbonate (total content of core material is 60-70wt%, and nano calcium carbonate accounts for 15-20% of the core material content), and the shell material is urea-formaldehyde resin; (3) Third stage: Add 0.8-1.2 parts of antioxidant compound system, 0.7-1.1 parts of anti-aging synergistic system and 0.6-1.0 parts of lubricating dispersant EBS, mix at 1000r / min for 5min to obtain uniform premix; the antioxidant compound system is composed of antioxidant 1010, antioxidant 168 and antioxidant DLTP in a mass ratio of 1:1:0.5; the anti-aging synergistic system is composed of ultraviolet absorber UV-327 and hindered amine light stabilizer GW-540 in a mass ratio of 2:1.
[0026] Gradient temperature controlled melt blending extrusion: The premixed material is added to a twin-screw extruder, and the extruder is equipped with gradient temperature control in each section: feed inlet 235-245℃, compression section 250-260℃, melting section 1 265-275℃, melting section 2 275-285℃, homogenization section 278-283℃, die head section 272-278℃, and die head section 268-273℃; the main extruder speed is 400-450 r / min, the feed speed is 90-110 r / min, and the die head pressure is 14-17 MPa; the melt is water-cooled at 25-30℃, pelletized, and screened to obtain composite material particles with a particle size of 2-3 mm.
[0027] Segmented vacuum drying: (1) First stage: Place the composite material particles in a vacuum drying oven and dry them at 80°C for 2 hours to remove surface moisture; (2) Second stage: Heat to 130℃ and continue vacuum drying for 5 hours to obtain the finished material.
[0028] Implementation effect A significant improvement in wear resistance: the wear amount is as low as 3.6mg / 1000 cycles, which is 12% lower than the best value of existing technology. After 20,000 cycles of friction, the wear amount is still ≤6.2mg / 1000 cycles, and there are no obvious scratches on the surface. It can withstand high-intensity outdoor sand and gravel friction and frequent daily scratches.
[0029] Excellent balance of toughness and stiffness: the notched impact strength of the cantilever beam reaches up to 92.7 kJ / m. 2 With a surface hardness (Rockwell R) ≥128, it improves impact strength by 15% and rigidity by 8% compared to traditional modified materials. It exhibits no brittleness in low-temperature (-20℃) environments, meeting the impact and drop resistance requirements of camera housings.
[0030] Outstanding long-lasting anti-aging performance: After 2000h UV aging test, the impact strength retention rate is ≥90.3%, the yellowing index is ≤1.2, and there is no yellowing, brittleness or cracking after 3 years of outdoor use. It is suitable for extreme climatic conditions such as high temperature and strong ultraviolet radiation.
[0031] Balancing processing and economic performance: dimensional shrinkage rate ≤0.4%, molding accuracy improved by 20% compared to traditional materials, meeting the injection molding needs of complex structures; wide injection molding process window, no special equipment required, and industrial production qualification rate ≥98%; cost reduced by more than 45% compared to pure PEEK materials and 10% compared to existing modified materials, combining performance and economy.
[0032] Environmentally friendly and highly adaptable: The raw materials are all commercially available environmentally friendly materials, and the preparation process has no waste emissions and complies with RoHS standards; it can be directly used for integrated injection molding of camera housings, and can also be extended to outdoor drones, security monitoring equipment, vehicle cameras and other products with strict requirements for wear resistance, aging resistance and toughness, with a wide range of application scenarios.
[0033] Example 3 A method for preparing wear-resistant engineering plastics for camera housings Secondary modification of composite fillers: (1) One-time modification: Take 12g of graphene-coated SiC composite filler, spray 2.0g of 10% rare earth coupling agent ethanol solution, mix at 1200r / min for 15min, and dry at 120℃ for 4h; (2) Secondary modification: Add a compound system of silane coupling agent KH560 and titanate coupling agent NDZ-311 (total mass 1.5g), ball mill at 300r / min for 2h, dry at 100℃ for 2h, and set aside.
[0034] Staged premixing: (1) First stage: Weigh 55 parts of PC (molecular weight 32000) and 20 parts of PEEK (viscosity average molecular weight 42000), mix at 800 r / min for 8 min; (2) Second stage: Add 12 parts of secondary modified composite filler and 8 parts of microcapsule toughening agent (core material contains 52wt% POE-g-MAH and 8wt% nano calcium carbonate), mix at 1000r / min for 10min; (3) Third stage: Add 1.0 part of antioxidant compound system (1010:168:DLTP=1:1:0.5), 0.9 part of anti-aging synergistic system (UV-327:GW-540=2:1), and 0.8 part of EBS, mix at 1000r / min for 5min.
[0035] Gradient temperature controlled melt extrusion: The twin-screw extruder has the following temperature gradients: feed inlet 240℃, compression section 255℃, melting section 1 270℃, melting section 2 280℃, homogenization section 280℃, die head section 275℃, and die head section 270℃; the main extruder speed is 420 r / min, the feed speed is 100 r / min, and the die head pressure is 15 MPa; the water cooling temperature is 28℃, and the extrusion process yields composite granules.
[0036] Segmented vacuum drying: 80℃ for 2 hours, 130℃ for 5 hours, injection molding (injection temperature 268℃, pressure 100MPa, holding pressure 65MPa, holding time 20s, cooling time 32s, mold temperature 78℃).
[0037] Performance test results: Notched impact strength of the cantilever beam: 90.5 kJ / m 2 Abrasion loss 3.6mg / 1000 cycles, heat distortion temperature 151℃, impact retention rate after 2000h UV aging 91.2%, surface hardness (Rockwell R) 130, dimensional shrinkage 0.38%, yellowing index 1.0.
[0038] Example 4 Pretreatment of composite filler: Take 11g of graphene-coated silicon carbide composite filler (SiC purity 99.5%, graphene coating amount 6wt%) and add it to a high-speed mixer. Spray 1.9g of 10% mass concentration rare earth coupling agent ethanol solution (lanthanum nitrate modified silane coupling agent KH550), and mix at 1200r / min at room temperature for 15min. Then dry in a vacuum drying oven at 120℃ for 4h for later use.
[0039] Premix: Weigh out 53 parts by weight of PC (molecular weight 31000), 17 parts by weight of PEEK (viscosity average molecular weight 41000), 11 parts by weight of pretreated composite filler, 7.5 parts by weight of microencapsulated toughening agent (particle size 5-7μm, core material is POE-g-MAH, core material content 63wt%, shell material is urea-formaldehyde resin), 0.95 parts by weight of antioxidant compound system (1010:168=1:1), 0.55 parts by weight of UV absorber UV-327, and 0.75 parts by weight of EBS. Add them sequentially to a high-speed mixer at a speed of 1000r / min and mix for 11.5min to obtain the premix.
[0040] Melt blending extrusion granulation: The premixed material is added to a twin-screw extruder. The extruder temperature range (feed inlet → die head) is 240℃, 255℃, 270℃, 280℃, 275℃, and 270℃. The main extruder speed is 415 r / min, the feed speed is 98 r / min, and the die head pressure is 15.5 MPa. The melt is water-cooled (water temperature 26℃) and pelletized to obtain composite particles with a particle size of 2-3 mm.
[0041] Injection molding: The composite material granules were vacuum dried at 130℃ for 5 hours and then added to the injection molding machine. The injection temperature was 263℃, the injection pressure was 98MPa, the holding pressure was 62MPa, the holding time was 19.5s, the cooling time was 31.5s, and the mold temperature was 76℃. The injection molding was used to form a sample of the action camera shell.
[0042] Performance test results: Notched impact strength of the cantilever beam: 83.2 kJ / m 2 Wear loss 4.4mg / 1000 cycles, heat distortion temperature 146℃, impact retention rate after 1000h UV aging 93.1%, surface hardness (Rockwell R) 121, dimensional shrinkage 0.43%.
[0043] Example 5 Pretreatment of composite filler: Take 14g of graphene-coated silicon carbide composite filler (SiC purity 99.5%, graphene coating amount 7wt%) and add it to a high-speed mixer. Spray 2.4g of 10% mass concentration rare earth coupling agent ethanol solution (lanthanum nitrate modified silane coupling agent KH550), and mix at room temperature for 15min at a speed of 1200r / min. Then dry in a vacuum drying oven at 120℃ for 4h for later use.
[0044] Premix: Weigh out 57 parts by weight of PC (molecular weight 34500), 23 parts by weight of PEEK (viscosity average molecular weight 44500), 14 parts by weight of pretreated composite filler, 9.5 parts by weight of microencapsulated toughening agent (particle size 7-10μm, core material is POE-g-MAH, core material content 69wt%, shell material is urea-formaldehyde resin), 1.15 parts by weight of antioxidant compound system (1010:168=1:1), 0.75 parts by weight of UV absorber UV-327, and 0.95 parts by weight of EBS. Add them sequentially to a high-speed mixer at a speed of 1000r / min and mix for 14.5min to obtain the premix.
[0045] Melt blending extrusion granulation: The premixed material is added to a twin-screw extruder. The extruder temperature range (feed inlet → die head) is 240℃, 255℃, 270℃, 280℃, 275℃, and 270℃. The main extruder speed is 445 r / min, the feed speed is 108 r / min, and the die head pressure is 16.5 MPa. The melt is water-cooled (water temperature 29.5℃) and pelletized to obtain composite granules with a particle size of 2-3 mm.
[0046] Injection molding: The composite material granules were vacuum dried at 130℃ for 5 hours and then added to the injection molding machine. The injection temperature was 273℃, the injection pressure was 108MPa, the holding pressure was 69MPa, the holding time was 21.5s, the cooling time was 34.5s, and the mold temperature was 83℃. The injection molding was used to form a sample of the action camera shell.
[0047] Performance test results: Notched impact strength of the cantilever beam: 84.7 kJ / m 2Abrasion loss 4.2 mg / 1000 cycles, heat distortion temperature 151℃, impact retention rate after 1000 h of UV aging 93.9%, surface hardness (Rockwell R) 124, dimensional shrinkage 0.41%.
[0048] The preferred embodiments of the present invention disclosed above are only for the purpose of illustrating the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation described herein. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can better understand and utilize the present invention.
Claims
1. A method for preparing a wear-resistant engineering plastic for camera housings, characterized in that: Includes the following steps: Step a: Secondary modification of composite filler: First, the graphene-coated SiC composite filler is modified and dried using a rare earth coupling agent ethanol solution. Then, it is modified by ball milling and dried using a silane-titanium ester composite coupling agent to obtain the secondary modified composite filler. Step b: Staged premixing: First, premix polycarbonate and polyether ketone ketone to obtain a blend matrix, then add secondary modified composite filler and microencapsulated toughening agent in sequence, and finally add antioxidant compound system, anti-aging synergistic system and lubricating dispersant EBS, and mix in stages to obtain premix; Step c: Gradient temperature controlled melt blending extrusion: The premixed material is added to a twin-screw extruder, and after gradient temperature controlled extrusion, water cooling, pelletizing, and screening, composite material particles are obtained; Step d: Segmented vacuum drying: The composite material particles are dried in two stages to obtain the finished material.
2. A process for the production of a wear-resistant engineering plastic for camera housings according to claim 1, characterized in that In step a, the purity of SiC in the graphene-coated SiC composite filler is ≥99.5%, and the graphene coating amount is 5-8wt%. The preparation method of the graphene-coated SiC composite filler is as follows: 100g of SiC powder with a particle size of 800-1200nm is dispersed in 500mL of deionized water and ultrasonically dispersed for 30min; 5g of graphene oxide is added, the pH is adjusted to 8-9, and the mixture is stirred at 80℃ for 2h; 10g of hydrazine hydrate is added, and the mixture is stirred for another 4h to reduce the graphene oxide to graphene. Filter and wash until neutral, then dry at 120℃ for 6 hours to obtain the final product.
3. A method of making a wear-resistant engineering plastic for camera housings according to claim 1, characterized in that: In step a, the mass concentration of the rare earth coupling agent ethanol solution is 10%, and the rare earth coupling agent is lanthanum nitrate modified silane coupling agent KH550; the mixing speed for the first modification is 1200 r / min, the mixing time is 15 min, the drying temperature is 120℃, and the drying time is 3-4 h.
4. The method of claim 1, wherein the method further comprises: In step a, the silane-titanium ester composite coupling agent is composed of silane coupling agent KH560 and titanate coupling agent NDZ-311 in a mass ratio of 1:0.8; the ball milling speed for secondary modification is 300 r / min, the ball milling time is 2 h, the drying temperature is 100 ℃, and the drying time is 2 h. 5. The method of claim 1, wherein the method further comprises: adding a lubricant to the mixture of the first and second polymers. The weight parts of each raw material in step b are as follows: 50-60 parts of polycarbonate, 15-20 parts of polyether ketone ketone, 8-15 parts of secondary modified composite filler, 6-10 parts of microencapsulated toughening agent, 0.8-1.2 parts of antioxidant compound system, 0.7-1.1 parts of anti-aging synergistic system, and 0.6-1.0 parts of EBS.
6. The method of claim 1, wherein the method further comprises: In step b, the molecular weight of polycarbonate is 30,000-35,000, and the viscosity-average molecular weight of polyether ketone is 40,000-45,000. The specific parameters for the staged premixing are: first stage: 800 r / min for 8 min; second stage: 1000 r / min for 10 min; third stage: 1000 r / min for 5 min.
7. The method for preparing a wear-resistant engineering plastic for a camera housing according to claim 1, characterized in that: In step b, the microcapsule toughening agent has a particle size of 5-10 μm, the core material is a composite system of POE-g-MAH and nano calcium carbonate, the total content of the core material is 60-70 wt%, nano calcium carbonate accounts for 15-20% of the core material, and the shell material is urea-formaldehyde resin.
8. A method for preparing a wear-resistant engineering plastic for a camera housing according to claim 1, characterized in that: In step b, the antioxidant compound system is composed of antioxidant 1010, antioxidant 168 and antioxidant DLTP in a mass ratio of 1:1:0.5; the anti-aging synergistic system is composed of ultraviolet absorber UV-327 and hindered amine light stabilizer GW-540 in a mass ratio of 2:
1.
9. A method for preparing a wear-resistant engineering plastic for a camera housing according to claim 1, characterized in that: The gradient temperatures of the twin-screw extruder in step c are as follows: feed inlet 235-245℃, compression section 250-260℃, first melting section 265-275℃, second melting section 275-285℃, homogenization section 278-283℃, front of die head 272-278℃, die head 268-273℃; main extruder speed 400-450 r / min, feed speed 90-110 r / min, die head pressure 14-17 MPa; water cooling temperature 25-30℃, and composite material particle size 2-3 mm.
10. The method of claim 1, wherein the abrasion resistant engineering plastic for camera housings is prepared by: The parameters for the segmented vacuum drying in step d are: first stage drying at 80℃ for 2 hours, and second stage drying at 130℃ for 5 hours.