Disclosure of Invention
The application provides a modified polycarbonate light-absorbing transparent plastic for laser welding and a preparation method thereof, aiming at solving the problems that the dispersibility of the existing external light-absorbing agent in a polycarbonate system and the binding force with resin are poor, the welding quality of polycarbonate plastic is affected and the like.
In a first aspect, the application provides a modified polycarbonate light-absorbing transparent plastic for laser welding, which adopts the following technical scheme:
The light absorbing transparent modified polycarbonate plastic for laser welding consists of polycarbonate 70-90 weight portions, polyamide 18-30 weight portions, thermoplastic polyester elastomer 5-10 weight portions, light absorbing slurry 2-5 weight portions, lubricant 0.5-1 weight portions and antioxidant 0.5-1 weight portions.
Preferably, the modified polycarbonate light-absorbing transparent plastic for laser welding comprises, by weight, 75-85 parts of polycarbonate, 22-26 parts of polyamide, 6-8 parts of thermoplastic polyester elastomer, 2.5-4.5 parts of light-absorbing slurry, 0.6-0.8 part of lubricant and 0.6-0.8 part of antioxidant.
Preferably, the modified polycarbonate light-absorbing transparent plastic for laser welding comprises the following raw materials, by weight, 80 parts of polycarbonate, 24 parts of polyamide, 7 parts of thermoplastic polyester elastomer, 3.5 parts of light-absorbing slurry, 0.7 part of lubricant and 0.7 part of antioxidant.
Preferably, the light absorbing slurry is prepared by mixing a light absorbing agent, N' N-dimethylformamide and polyvinylpyrrolidone and then performing ultrasonic dispersion.
Preferably, the mass ratio of the light absorber to the N' N-dimethylformamide to the polyvinylpyrrolidone is 1:1.8-2.2:0.1-0.2.
Preferably, the ultrasonic power is 500-600W, and the ultrasonic time is 1-2h.
Preferably, the lubricant is at least one of pentaerythritol stearate, zinc stearate and calcium stearate.
Preferably, the antioxidant is at least one of antioxidant 1010, antioxidant 1076 and antioxidant 168.
In a second aspect, the application provides a preparation method of modified polycarbonate light-absorbing transparent plastic for laser welding, which adopts the following technical scheme:
the preparation method of the modified polycarbonate light-absorbing transparent plastic for laser welding specifically comprises the following preparation steps:
S1, weighing polycarbonate, polyamide, thermoplastic polyester elastomer, light absorption slurry, lubricant and antioxidant according to parts by weight for standby;
S2, pre-drying the polycarbonate, adding the pre-dried polycarbonate, the polyamide, the thermoplastic polyester elastomer, the light absorption slurry, the lubricant and the antioxidant into a mixing mill, stirring, mixing, extruding and granulating to obtain the modified polycarbonate light absorption transparent plastic for laser welding.
In summary, the application has the following beneficial effects:
The application uses the polycarbonate, the polyamide and the thermoplastic polyester elastomer together for producing the laser welding plastic, and the polycarbonate, the polyamide and the thermoplastic polyester elastomer are all thermoplastic materials, have good processability, can realize characteristic complementation by sharing the three materials, obviously improve the overall strength, the toughness, the thermal stability and the impact resistance of the welding plastic, optimize the optical performance of the welding plastic, and further easily manufacture welding parts with complex shapes, and improve the laser welding efficiency and the welding quality.
The application selects the carbon nano tube, nano barium titanate and nano silver to be compounded as the light absorber, the carbon nano tube, the nano barium titanate and the nano silver respectively have different optical characteristics, in addition, the carbon nano tube has higher electric conduction and heat conduction performance on the nano scale, in the welding process, the energy can be more effectively transferred to a welding area to realize local heating and melting, the three are compounded for use, the conversion of laser energy into heat energy is facilitated, the absorption capacity of laser in different wavelength ranges is enhanced, the light absorption efficiency is improved, the welding process is promoted, and meanwhile, the addition amount of the light absorber is reduced, and the cost is further reduced.
According to the application, the light absorber is prepared into the light absorbing slurry in advance and then added into the polycarbonate system, so that the addition amount of the light absorber can be controlled more accurately, uniform and stable dispersion of the light absorber in the polycarbonate system can be realized, precipitation or aggregation of the light absorber components can be prevented, further, the light absorber can be ensured to be fully utilized, and the laser welding efficiency can be improved.
Detailed Description
The present application will be described in further detail with reference to examples.
The polycarbonate is bisphenol A type aromatic polycarbonate, the weight average molecular weight is 21500,1300-10NP, LG chemistry, the viscosity of polyamide is 90-180/mPa.s (25 ℃), HY-388, anhui hongtai New Material Co., ltd.), the thermoplastic polyester elastomer KP3355 is available in the Kelong chemical industry, the nano barium titanate content is more than or equal to 99.9%, the average particle size is 100nm, the nano silver purity is more than or equal to 99.9%, the average particle size is 20nm, the carbon nano tube is multi-wall carbon nano tube, the purity is more than or equal to 95%, the length is 20-50um, and the diameter is 8-14nm.
Example 1
The application provides a modified polycarbonate light-absorbing transparent plastic for laser welding, which adopts the following technical scheme:
The modified polycarbonate light-absorbing transparent plastic for laser welding comprises the following raw materials, by weight, 70 parts of polycarbonate, 18 parts of polyamide, 5 parts of thermoplastic polyester elastomer, 2 parts of light-absorbing slurry, 0.5 part of lubricant and 0.5 part of antioxidant;
wherein the light absorbing slurry is prepared by the following method:
A1, uniformly stirring and mixing the carbon nano tube, the nano barium titanate and the nano silver according to the mass ratio of 1:0.4:0.1 to obtain a light absorbent;
A2, mixing a light absorbing agent, N' N-dimethylformamide and polyvinylpyrrolidone according to a mass ratio of 1:1.8:0.1, controlling the ultrasonic power to be 500W, and dispersing for 2 hours to prepare light absorbing slurry;
The lubricant is pentaerythritol stearate;
The antioxidant is antioxidant 1010.
The application also provides a preparation method of the modified polycarbonate light-absorbing transparent plastic for laser welding, which specifically comprises the following preparation steps:
S1, weighing polycarbonate, polyamide, thermoplastic polyester elastomer, light absorption slurry, lubricant and antioxidant according to parts by weight for standby;
S2, pre-drying polycarbonate at the temperature of 95 ℃ for 2 hours, adding the pre-dried polycarbonate, polyamide, thermoplastic polyester elastomer, light-absorbing slurry, lubricant and antioxidant into a mixing roll, controlling the stirring rotation speed to be 700r/min, mixing the mixture at the temperature of 195 ℃, stirring and mixing the mixture for 20 minutes, adding the mixture into a double-screw extruder, and extruding and granulating the mixture at the temperature of 150 ℃ to obtain the modified polycarbonate light-absorbing transparent plastic for laser welding.
Example 2
The application provides a modified polycarbonate light-absorbing transparent plastic for laser welding, which adopts the following technical scheme:
The modified polycarbonate light-absorbing transparent plastic for laser welding comprises the following raw materials, by weight, 75 parts of polycarbonate, 22 parts of polyamide, 6 parts of thermoplastic polyester elastomer, 2.5 parts of light-absorbing slurry, 0.6 part of lubricant and 0.6 part of antioxidant;
wherein the light absorbing slurry is prepared by the following method:
a1, uniformly stirring and mixing the carbon nano tube, the nano barium titanate and the nano silver according to the mass ratio of 1:0.4:0.3 to obtain a light absorbent;
a2, mixing the light absorbing agent, N' N-dimethylformamide and polyvinylpyrrolidone according to a mass ratio of 1:1.8:0.2, controlling the ultrasonic power to be 520W, and dispersing for 1.8h to obtain light absorbing slurry;
The lubricant is zinc stearate;
the antioxidant is antioxidant 1076.
The application also provides a preparation method of the modified polycarbonate light-absorbing transparent plastic for laser welding, which specifically comprises the following preparation steps:
S1, weighing polycarbonate, polyamide, thermoplastic polyester elastomer, light absorption slurry, lubricant and antioxidant according to parts by weight for standby;
S2, pre-drying polycarbonate at 100 ℃ for 4.5 hours, adding the pre-dried polycarbonate, polyamide, thermoplastic polyester elastomer, light-absorbing slurry, lubricant and antioxidant into a mixing roll, controlling the stirring rotation speed to be 800r/min, mixing at 190 ℃ for 15 minutes, adding the mixed materials into a double-screw extruder, and extruding and granulating at 160 ℃ to obtain the modified polycarbonate light-absorbing transparent plastic for laser welding.
Example 3
The application provides a modified polycarbonate light-absorbing transparent plastic for laser welding, which adopts the following technical scheme:
The modified polycarbonate light-absorbing transparent plastic for laser welding comprises the following raw materials, by weight, 80 parts of polycarbonate, 24 parts of polyamide, 7 parts of thermoplastic polyester elastomer, 3.5 parts of light-absorbing slurry, 0.7 part of lubricant and 0.7 part of antioxidant;
wherein the light absorbing slurry is prepared by the following method:
a1, uniformly stirring and mixing the carbon nano tube, the nano barium titanate and the nano silver according to the mass ratio of 1:0.5:0.2 to obtain a light absorbent;
A2, mixing a light absorbing agent, N' N-dimethylformamide and polyvinylpyrrolidone according to a mass ratio of 1:2:0.15, controlling the ultrasonic power to be 550W, and dispersing for 1.5h to prepare light absorbing slurry;
the lubricant is calcium stearate;
The antioxidant is antioxidant 168.
The application also provides a preparation method of the modified polycarbonate light-absorbing transparent plastic for laser welding, which specifically comprises the following preparation steps:
S1, weighing polycarbonate, polyamide, thermoplastic polyester elastomer, light absorption slurry, lubricant and antioxidant according to parts by weight for standby;
S2, pre-drying the polycarbonate at 105 ℃ for 3.5 hours, adding the pre-dried polycarbonate, the polyamide, the thermoplastic polyester elastomer, the light absorption slurry, the lubricant and the antioxidant into a mixing roll, controlling the stirring rotation speed to 850r/min, mixing at 185 ℃ for 20 minutes, adding the mixed material into a double-screw extruder, and extruding and granulating at 170 ℃ to obtain the modified polycarbonate light absorption transparent plastic for laser welding.
Example 4
The application provides a modified polycarbonate light-absorbing transparent plastic for laser welding, which adopts the following technical scheme:
The modified polycarbonate light-absorbing transparent plastic for laser welding comprises the following raw materials, by weight, 85 parts of polycarbonate, 26 parts of polyamide, 8 parts of thermoplastic polyester elastomer, 4.5 parts of light-absorbing slurry, 0.8 part of lubricant and 0.8 part of antioxidant;
wherein the light absorbing slurry is prepared by the following method:
A1, uniformly stirring and mixing the carbon nano tube, the nano barium titanate and the nano silver according to the mass ratio of 1:0.6:0.1 to obtain a light absorbent;
A2, mixing a light absorbing agent, N' N-dimethylformamide and polyvinylpyrrolidone according to a mass ratio of 1:2.2:0.1, controlling ultrasonic power to be 580W, and dispersing for 1.2h to obtain light absorbing slurry;
The lubricant is pentaerythritol stearate;
The antioxidant is antioxidant 1010.
The application also provides a preparation method of the modified polycarbonate light-absorbing transparent plastic for laser welding, which specifically comprises the following preparation steps:
S1, weighing polycarbonate, polyamide, thermoplastic polyester elastomer, light absorption slurry, lubricant and antioxidant according to parts by weight for standby;
S2, pre-drying the polycarbonate at the temperature of 110 ℃ for 2.5 hours, adding the pre-dried polycarbonate, the polyamide, the thermoplastic polyester elastomer, the light absorption slurry, the lubricant and the antioxidant into a mixing roll, controlling the stirring rotation speed to 900r/min, mixing at the temperature of 180 ℃, stirring and mixing for 25 minutes, adding the mixture into a double-screw extruder, and extruding and granulating at the temperature of 190 ℃ to obtain the modified polycarbonate light absorption transparent plastic for laser welding.
Example 5
The application provides a modified polycarbonate light-absorbing transparent plastic for laser welding, which adopts the following technical scheme:
The modified polycarbonate light-absorbing transparent plastic for laser welding comprises the following raw materials, by weight, 90 parts of polycarbonate, 30 parts of polyamide, 10 parts of thermoplastic polyester elastomer, 5 parts of light-absorbing slurry, 1 part of lubricant and 1 part of antioxidant;
wherein the light absorbing slurry is prepared by the following method:
A1, uniformly stirring and mixing the carbon nano tube, the nano barium titanate and the nano silver according to the mass ratio of 1:0.6:0.3 to obtain a light absorbent;
A2, mixing a light absorbing agent, N' N-dimethylformamide and polyvinylpyrrolidone according to a mass ratio of 1:2.2:0.2, controlling the ultrasonic power to be 600W, and dispersing for 1h to obtain light absorbing slurry;
The lubricant is pentaerythritol stearate;
The antioxidant is antioxidant 1010.
The application also provides a preparation method of the modified polycarbonate light-absorbing transparent plastic for laser welding, which specifically comprises the following preparation steps:
S1, weighing polycarbonate, polyamide, thermoplastic polyester elastomer, light absorption slurry, lubricant and antioxidant according to parts by weight for standby;
S2, pre-drying polycarbonate at 115 ℃ for 2 hours, adding the pre-dried polycarbonate, polyamide, thermoplastic polyester elastomer, light-absorbing slurry, lubricant and antioxidant into a mixing roll, controlling the stirring rotation speed to 1000r/min, mixing at 175 ℃ for 18 minutes, adding the mixture into a double-screw extruder, and extruding and granulating at 200 ℃ to obtain the modified polycarbonate light-absorbing transparent plastic for laser welding.
Comparative example 1
The application provides a modified polycarbonate light-absorbing transparent plastic for laser welding, which adopts the following technical scheme:
The modified polycarbonate light-absorbing transparent plastic for laser welding comprises the following raw materials, by weight, 70 parts of polycarbonate, 23 parts of polyamide, 2 parts of light-absorbing slurry, 0.5 part of lubricant and 0.5 part of antioxidant;
wherein the light absorbing slurry is prepared by the following method:
A1, uniformly stirring and mixing the carbon nano tube, the nano barium titanate and the nano silver according to the mass ratio of 1:0.4:0.1 to obtain a light absorbent;
A2, mixing a light absorbing agent, N' N-dimethylformamide and polyvinylpyrrolidone according to a mass ratio of 1:1.8:0.1, controlling the ultrasonic power to be 500W, and dispersing for 2 hours to prepare light absorbing slurry;
The lubricant is pentaerythritol stearate;
The antioxidant is antioxidant 1010.
The application also provides a preparation method of the modified polycarbonate light-absorbing transparent plastic for laser welding, which specifically comprises the following preparation steps:
S1, weighing polycarbonate, polyamide, light absorption slurry, a lubricant and an antioxidant for standby according to parts by weight;
S2, pre-drying polycarbonate at the temperature of 95 ℃ for 2 hours, adding the pre-dried polycarbonate, the polyamide light-absorbing slurry, the lubricant and the antioxidant into a mixing roll, controlling the stirring rotation speed to be 700r/min, mixing at the temperature of 195 ℃, stirring and mixing for 20 minutes, adding the mixture into a double-screw extruder, and extruding and granulating at the temperature of 150 ℃ to obtain the modified polycarbonate light-absorbing transparent plastic for laser welding.
Comparative example 2
The application provides a modified polycarbonate light-absorbing transparent plastic for laser welding, which adopts the following technical scheme:
The modified polycarbonate light-absorbing transparent plastic for laser welding comprises the following raw materials, by weight, 93 parts of polycarbonate, 2 parts of light-absorbing slurry, 0.5 part of lubricant and 0.5 part of antioxidant;
wherein the light absorbing slurry is prepared by the following method:
A1, uniformly stirring and mixing the carbon nano tube, the nano barium titanate and the nano silver according to the mass ratio of 1:0.4:0.1 to obtain a light absorbent;
A2, mixing a light absorbing agent, N' N-dimethylformamide and polyvinylpyrrolidone according to a mass ratio of 1:1.8:0.1, controlling the ultrasonic power to be 500W, and dispersing for 2 hours to prepare light absorbing slurry;
The lubricant is pentaerythritol stearate;
The antioxidant is antioxidant 1010.
The application also provides a preparation method of the modified polycarbonate light-absorbing transparent plastic for laser welding, which specifically comprises the following preparation steps:
S1, weighing polycarbonate, light absorption slurry, a lubricant and an antioxidant according to parts by weight for standby;
S2, pre-drying the polycarbonate at the temperature of 95 ℃ for 2 hours, adding the pre-dried polycarbonate, the light-absorbing slurry, the lubricant and the antioxidant into a mixing roll, controlling the stirring rotation speed to be 700r/min, mixing the mixture at the temperature of 195 ℃ for 20 minutes, adding the mixed mixture into a double-screw extruder, and extruding and granulating at the temperature of 150 ℃ to obtain the modified polycarbonate light-absorbing transparent plastic for laser welding.
Comparative example 3
The application provides a modified polycarbonate light-absorbing transparent plastic for laser welding, which adopts the following technical scheme:
The modified polycarbonate light-absorbing transparent plastic for laser welding comprises the following raw materials, by weight, 70 parts of polycarbonate, 18 parts of polyamide, 5 parts of thermoplastic polyester elastomer, 2 parts of light absorber, 0.5 part of lubricant and 0.5 part of antioxidant;
wherein the light absorber is prepared by uniformly stirring and mixing a carbon nano tube, nano barium titanate and nano silver according to the mass ratio of 1:0.4:0.1;
The lubricant is pentaerythritol stearate;
The antioxidant is antioxidant 1010.
The application also provides a preparation method of the modified polycarbonate light-absorbing transparent plastic for laser welding, which specifically comprises the following preparation steps:
s1, weighing polycarbonate, polyamide, thermoplastic polyester elastomer, light absorber, lubricant and antioxidant according to parts by weight for standby;
s2, pre-drying polycarbonate at the temperature of 95 ℃ for 2 hours, adding the pre-dried polycarbonate, the polyamide, the thermoplastic polyester elastomer, the light absorber, the lubricant and the antioxidant into a mixing mill, controlling the stirring rotation speed to be 700r/min, mixing the mixture at the temperature of 195 ℃, stirring and mixing the mixture for 20 minutes, adding the mixture into a double-screw extruder, and extruding and granulating the mixture at the temperature of 150 ℃ to obtain the modified polycarbonate light-absorbing transparent plastic for laser welding.
Comparative example 4
The application provides a modified polycarbonate light-absorbing transparent plastic for laser welding, which adopts the following technical scheme:
the modified polycarbonate light-absorbing transparent plastic for laser welding comprises the following raw materials, by weight, 70 parts of polycarbonate, 18 parts of polyamide, 5 parts of thermoplastic polyester elastomer, 0.7 part of light absorber, 0.5 part of lubricant and 0.5 part of antioxidant;
wherein the light absorber is prepared by uniformly stirring and mixing a carbon nano tube, nano barium titanate and nano silver according to the mass ratio of 1:0.4:0.1;
A2, mixing a light absorbing agent, N' N-dimethylformamide and polyvinylpyrrolidone according to a mass ratio of 1:1.8:0.1, controlling the ultrasonic power to be 500W, and dispersing for 2 hours to prepare light absorbing slurry;
The lubricant is pentaerythritol stearate;
The antioxidant is antioxidant 1010.
The application also provides a preparation method of the modified polycarbonate light-absorbing transparent plastic for laser welding, which specifically comprises the following preparation steps:
s1, weighing polycarbonate, polyamide, thermoplastic polyester elastomer, light absorber, lubricant and antioxidant according to parts by weight for standby;
s2, pre-drying polycarbonate at the temperature of 95 ℃ for 2 hours, adding the pre-dried polycarbonate, the polyamide, the thermoplastic polyester elastomer, the light absorber, the lubricant and the antioxidant into a mixing mill, controlling the stirring rotation speed to be 700r/min, mixing the mixture at the temperature of 195 ℃, stirring and mixing the mixture for 20 minutes, adding the mixture into a double-screw extruder, and extruding and granulating the mixture at the temperature of 150 ℃ to obtain the modified polycarbonate light-absorbing transparent plastic for laser welding.
Comparative example 5
The application provides a modified polycarbonate light-absorbing transparent plastic for laser welding, which adopts the following technical scheme:
The modified polycarbonate light-absorbing transparent plastic for laser welding comprises the following raw materials, by weight, 70 parts of polycarbonate, 18 parts of polyamide, 5 parts of thermoplastic polyester elastomer, 2 parts of light-absorbing slurry, 0.5 part of lubricant and 0.5 part of antioxidant;
wherein the light absorbing slurry is prepared by the following method:
A1, uniformly stirring and mixing the carbon nano tube and nano barium titanate according to the mass ratio of 1:0.5 to obtain a light absorbent;
A2, mixing a light absorbing agent, N' N-dimethylformamide and polyvinylpyrrolidone according to a mass ratio of 1:1.8:0.1, controlling the ultrasonic power to be 500W, and dispersing for 2 hours to prepare light absorbing slurry;
The lubricant is pentaerythritol stearate;
The antioxidant is antioxidant 1010.
The application also provides a preparation method of the modified polycarbonate light-absorbing transparent plastic for laser welding, which specifically comprises the following preparation steps:
S1, weighing polycarbonate, polyamide, thermoplastic polyester elastomer, light absorption slurry, lubricant and antioxidant according to parts by weight for standby;
S2, pre-drying polycarbonate at the temperature of 95 ℃ for 2 hours, adding the pre-dried polycarbonate, polyamide, thermoplastic polyester elastomer, light-absorbing slurry, lubricant and antioxidant into a mixing roll, controlling the stirring rotation speed to be 700r/min, mixing the mixture at the temperature of 195 ℃, stirring and mixing the mixture for 20 minutes, adding the mixture into a double-screw extruder, and extruding and granulating the mixture at the temperature of 150 ℃ to obtain the modified polycarbonate light-absorbing transparent plastic for laser welding.
Performance testing
The modified polycarbonate light-absorbing transparent plastic particles for laser welding prepared in examples 1 to 5 and comparative examples 1 to 5 of the present application were injection molded into 100mm x 2mm highlight plates under the same injection molding process conditions, and near infrared projection and reflection data were collected in a spectrophotometer 960nm, with absorptivity=100% -transmissivity-reflectivity.
The injection-molded highlight plate and the transparent PMMA plate were placed alternately together, and irradiated with a semiconductor laser (960 nm) having a beam diameter of 2 mm. The laser intensity was controlled to 40W, the welding speed was controlled to 40mm/s, and the surface state of the welded template was compared. The laser welded test pieces were sawed into strips of 10mm width, the tensile shear strength was measured by a tensile tester, the weld strength was calculated from the tensile shear strength, and the weld strength was tensile strength/(width of weld seam. Length of weld seam), and the results are shown in table 1 below:
as can be seen from the data shown in Table 1, the modified polycarbonate light-absorbing transparent plastic for laser welding prepared in examples 1 to 5 of the present application has high laser welding efficiency, high welding quality, high light-absorbing efficiency and excellent comprehensive properties.
From examples and comparative examples 1-2, it is evident that the combination of the addition of polyamide and thermoplastic polyester elastomer in a polycarbonate system can significantly improve the overall properties of the welded plastic.
As can be seen from example 1 and comparative examples 3 to 4, the conductive agent is added to the polycarbonate system after being prepared into the conductive paste, which is helpful for realizing uniform and stable dispersion of the light absorber in the polycarbonate system, preventing precipitation or aggregation of the light absorber component, further ensuring that the light absorber is fully utilized, and further improving the laser welding efficiency.
As can be seen from example 1 and comparative example 5, the light absorption efficiency can be remarkably improved and the welding process can be promoted by selecting the carbon nanotubes, nano barium titanate and nano silver as the light absorbent.
The present embodiment is only for explanation of the present application and is not to be construed as limiting the present application, and modifications to the present embodiment, which may not creatively contribute to the present application as required by those skilled in the art after reading the present specification, are all protected by patent laws within the scope of claims of the present application.