CN117126525A - Modified polycarbonate light-absorbing transparent plastic for laser welding and preparation method thereof - Google Patents

Abstract

The application relates to the technical field of laser plastic welding, and in particular discloses modified polycarbonate light-absorbing transparent plastic for laser welding and a preparation method thereof, wherein the modified polycarbonate light-absorbing transparent plastic for laser welding comprises the following raw materials: polycarbonates, polyamides, thermoplastic polyester elastomers, light absorbing slurries, lubricants, antioxidants; the preparation method comprises the steps of pre-drying polycarbonate, adding the pre-dried polycarbonate, polyamide, thermoplastic polyester elastomer, light absorption slurry, lubricant and antioxidant into a mixing mill together, stirring, mixing, extruding and granulating to obtain the modified polycarbonate; 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 in common, obviously improve the overall strength, the toughness, the thermal stability and the impact resistance of the welding plastic, and optimize the optical performance of the welding plastic; thereby improving the laser welding efficiency and welding quality.

Description

A modified polycarbonate light-absorbing transparent plastic for laser welding and its preparation method

Technical field

The present application relates to the technical field of laser plastic welding, and more specifically, to a modified polycarbonate light-absorbing transparent plastic for laser welding and a preparation method thereof.

Background technique

Laser transmission welding plastic technology is an emerging welding technology. Compared with traditional plastic welding methods such as hot plate welding, hot gas welding, electromagnetic induction welding, resistance induction welding, friction welding, ultrasonic welding and radio frequency Welding method, etc. The laser transmission welding method has many advantages such as fast welding speed, high degree of automation, small heat affected zone, low processing stress, no contact, no residue, precision, high bonding strength, small weld deformation, energy saving, environmental protection and greenness. , plastic products welded by laser transmission welding are widely used in automobile parts manufacturing, medical, electronics, food packaging and other fields, and have received widespread attention at home and abroad.

Polycarbonate (PC) is a widely used high-performance engineering plastic. It is a transparent colorless or slightly yellow strong solid with a transparency of up to 90%, second only to polymethylmethacrylate (PMMA) and Polystyrene (PS) and PC have good comprehensive mechanical properties, are rigid and tough, have good light transmittance, impact resistance, dimensional stability, electrical insulation properties, heat resistance and non-toxicity, and can be used in relatively It maintains high mechanical strength in a wide temperature range, but has poor fatigue resistance, wear resistance, and lubricity, and is prone to stress cracking. In related technologies, polycarbonate is often modified by adding other resins or inorganic fillers. However, PC has poor compatibility with other resins and is not easy to form a uniform blend system, which can easily lead to a decrease in the mechanical properties and transparency of polycarbonate. In addition, when polycarbonate is used for laser welding, its absorption rate of laser light is low and external light absorbers are often required. Commonly used external light absorbers such as carbon black and metal particles have poor dispersion in the polycarbonate system and poor bonding with resin. , will affect the performance of polycarbonate plastic products, which will in turn affect the welding quality of polycarbonate. Based on the above statements, this application provides a modified polycarbonate light-absorbing transparent plastic for laser welding and a preparation method thereof.

Contents of the invention

In order to solve the existing problems of poor dispersion of external light-absorbing agents in polycarbonate systems and poor bonding strength with resin, which affects the welding quality of polycarbonate plastics, this application provides a modified polycarbonate light-absorbing transparent plastic for laser welding. and preparation method thereof.

In the first aspect, this application provides a modified polycarbonate light-absorbing transparent plastic for laser welding, adopting the following technical solution:

A modified polycarbonate light-absorbing transparent plastic for laser welding, including the following raw materials in parts by weight: 70-90 parts by weight of polycarbonate, 18-30 parts by polyamide, 5-10 parts by thermoplastic polyester elastomer, and 2 parts by weight of light-absorbing slurry -5 parts, lubricant 0.5-1 part, antioxidant 0.5-1 part.

Preferably, the modified polycarbonate light-absorbing transparent plastic for laser welding includes the following raw materials in parts by weight: 75-85 parts of polycarbonate, 22-26 parts of polyamide, 6-8 parts of thermoplastic polyester elastomer, light-absorbing plastic 2.5-4.5 parts of slurry, 0.6-0.8 parts of lubricant, and 0.6-0.8 parts of antioxidant.

Preferably, the modified polycarbonate light-absorbing transparent plastic for laser welding includes the following parts by weight of raw materials: 80 parts of polycarbonate, 24 parts of polyamide, 7 parts of thermoplastic polyester elastomer, 3.5 parts of light-absorbing slurry, lubricant 0.7 parts of antioxidants and 0.7 parts of antioxidants.

Preferably, the light-absorbing slurry is obtained by mixing a light-absorbing agent with N’N-dimethylformamide and polyvinylpyrrolidone and then ultrasonic dispersion.

Preferably, the mass ratio of the light absorber, N’N-dimethylformamide and 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 the second aspect, this application provides a method for preparing modified polycarbonate light-absorbing transparent plastic for laser welding, adopting the following technical solution:

A method for preparing modified polycarbonate light-absorbing transparent plastic for laser welding, specifically including the following preparation steps:

S1. In parts by weight, weigh polycarbonate, polyamide, thermoplastic polyester elastomer, light-absorbing slurry, lubricant, and antioxidant for later use;

S2. After pre-drying the polycarbonate, add it to the mixer together with polyamide, thermoplastic polyester elastomer, light-absorbing slurry, lubricant and antioxidant, stir and knead, then extrude and granulate to obtain the desired result. Modified polycarbonate light-absorbing transparent plastic for laser welding.

To sum up, this application has the following beneficial effects:

In this application, polycarbonate, polyamide and thermoplastic polyester elastomer are used together to produce laser welding plastics. All three are thermoplastic materials with good processability. The use of the three can achieve complementary characteristics and significantly improve the quality of welding plastics. The overall strength, toughness, thermal stability and impact resistance optimize the optical properties of plastics for welding; thus making it easier to manufacture complex-shaped welded parts and improving laser welding efficiency and welding quality.

This application uses a combination of carbon nanotubes, nano-barium titanate and nano-silver as the light absorber. Carbon nanotubes, nano-barium titanate and nano-silver have different optical properties respectively. In addition, carbon nanotubes have higher properties at the nanometer scale. Excellent electrical and thermal conductivity, during the welding process, it can transfer energy to the welding area more effectively to achieve local heating and melting; the combined use of the three helps to convert laser energy into thermal energy to achieve different wavelengths. Enhance the laser absorption capacity, improve the light absorption efficiency, and promote the welding process; at the same time, reduce the amount of light absorber added, thereby reducing the cost.

By preforming the light absorbing agent into a light absorbing slurry and then adding it to the polycarbonate system, this application can more accurately control the amount of light absorbing agent added, which helps to achieve uniform and stable dispersion of the light absorbing agent in the polycarbonate system, preventing the light absorbing agent from being Precipitation or aggregation of components occurs, thereby ensuring that the light absorber is fully utilized, thereby improving laser welding efficiency.

Detailed ways

The present application will be further described in detail below in conjunction with examples.

The raw materials selected in the examples are as follows: the polycarbonate is bisphenol A aromatic polycarbonate, the weight average molecular weight is 21500, 1300-10NP, LG Chem; the polyamide viscosity is 90-180/mPa·s (25°C), HY- 388, Anhui Hongtai New Materials Co., Ltd.; thermoplastic polyester elastomer KP3355, Kolon Chemical; nanobarium titanate content ≥99.9%, average particle size is 100nm; nanosilver purity ≥99.9%, average particle size is 20nm; Carbon nanotubes are multi-walled carbon nanotubes with a purity of ≥95%, a length of 20-50um, and a diameter of 8-14nm.

Example 1

This application provides a modified polycarbonate light-absorbing transparent plastic for laser welding, adopting the following technical solution:

A modified polycarbonate light-absorbing transparent plastic for laser welding, including 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, and 0.5 parts of lubricant , antioxidant 0.5 parts;

The light-absorbing slurry is prepared by the following method:

A1. Stir and mix carbon nanotubes, nanobarium titanate and nanosilver in a mass ratio of 1:0.4:0.1 to obtain a light absorber;

A2. Mix the light absorber, N’N-dimethylformamide and polyvinylpyrrolidone according to the mass ratio of 1:1.8:0.1, control the ultrasonic power to 500W, the ultrasonic time to 2h, and disperse to prepare the light-absorbing slurry;

The lubricant is pentaerythritol stearate;

The antioxidant is antioxidant 1010.

This application also provides a method for preparing modified polycarbonate light-absorbing transparent plastic for laser welding, which specifically includes the following preparation steps:

S1. In parts by weight, weigh polycarbonate, polyamide, thermoplastic polyester elastomer, light-absorbing slurry, lubricant, and antioxidant for later use;

S2. After pre-drying the polycarbonate at 95°C for 2 hours, add it to the mixer together with polyamide, thermoplastic polyester elastomer, light-absorbing slurry, lubricant and antioxidant, and control the stirring speed to 700r /min, the mixing temperature is 195°C. After stirring and mixing for 20 minutes, add it to a twin-screw extruder and extrude and granulate at 150°C to obtain the required modified polycarbonate light-absorbing transparent plastic for laser welding.

Example 2

This application provides a modified polycarbonate light-absorbing transparent plastic for laser welding, adopting the following technical solution:

A modified polycarbonate light-absorbing transparent plastic for laser welding, including 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, and 0.6 parts of lubricant , antioxidant 0.6 parts;

The light-absorbing slurry is prepared by the following method:

A1. Stir and mix carbon nanotubes, nanobarium titanate and nanosilver in a mass ratio of 1:0.4:0.3 to obtain a light absorber;

A2. Mix the light absorber, N’N-dimethylformamide and polyvinylpyrrolidone according to the mass ratio of 1:1.8:0.2, control the ultrasonic power to 520W, the ultrasonic time to 1.8h, and disperse to prepare the light-absorbing slurry;

The lubricant is zinc stearate;

The antioxidant is antioxidant 1076.

This application also provides a method for preparing modified polycarbonate light-absorbing transparent plastic for laser welding, which specifically includes the following preparation steps:

S1. In parts by weight, weigh polycarbonate, polyamide, thermoplastic polyester elastomer, light-absorbing slurry, lubricant, and antioxidant for later use;

S2. After pre-drying the polycarbonate at 100°C for 4.5 hours, add it to the mixer together with polyamide, thermoplastic polyester elastomer, light-absorbing slurry, lubricant and antioxidant, and control the stirring speed to 800r/min, the mixing temperature is 190°C. After stirring and mixing for 15 minutes, add it to the twin-screw extruder and extrude and granulate at 160°C to obtain the required modified polycarbonate light-absorbing transparent plastic for laser welding.

Example 3

This application provides a modified polycarbonate light-absorbing transparent plastic for laser welding, adopting the following technical solution:

A modified polycarbonate light-absorbing transparent plastic for laser welding, including 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, and 0.7 parts of lubricant , antioxidant 0.7 parts;

The light-absorbing slurry is prepared by the following method:

A1. Stir and mix carbon nanotubes, nanobarium titanate and nanosilver in a mass ratio of 1:0.5:0.2 to obtain a light absorber;

A2. Mix the light absorber, N’N-dimethylformamide and polyvinylpyrrolidone according to the mass ratio of 1:2:0.15, control the ultrasonic power to 550W, the ultrasonic time to 1.5h, and disperse to prepare the light-absorbing slurry;

The lubricant is calcium stearate;

The antioxidant is antioxidant 168.

This application also provides a method for preparing modified polycarbonate light-absorbing transparent plastic for laser welding, which specifically includes the following preparation steps:

S1. In parts by weight, weigh polycarbonate, polyamide, thermoplastic polyester elastomer, light-absorbing slurry, lubricant, and antioxidant for later use;

S2. After pre-drying the polycarbonate at 105°C for 3.5 hours, add it to the mixer together with polyamide, thermoplastic polyester elastomer, light-absorbing slurry, lubricant and antioxidant, and control the stirring speed to 850r/min, the mixing temperature is 185°C. After stirring and mixing for 20 minutes, add it to the twin-screw extruder and extrude and granulate at 170°C to obtain the required modified polycarbonate light-absorbing transparent plastic for laser welding.

Example 4

This application provides a modified polycarbonate light-absorbing transparent plastic for laser welding, adopting the following technical solution:

A modified polycarbonate light-absorbing transparent plastic for laser welding, including 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, and 0.8 parts of lubricant , antioxidant 0.8 parts;

The light-absorbing slurry is prepared by the following method:

A1. Stir and mix carbon nanotubes, nanobarium titanate and nanosilver in a mass ratio of 1:0.6:0.1 to obtain a light absorber;

A2. Mix the light absorber, N’N-dimethylformamide and polyvinylpyrrolidone according to the mass ratio of 1:2.2:0.1, control the ultrasonic power to 580W, the ultrasonic time to 1.2h, and disperse to prepare the light-absorbing slurry;

The lubricant is pentaerythritol stearate;

The antioxidant is antioxidant 1010.

This application also provides a method for preparing modified polycarbonate light-absorbing transparent plastic for laser welding, which specifically includes the following preparation steps:

S1. In parts by weight, weigh polycarbonate, polyamide, thermoplastic polyester elastomer, light-absorbing slurry, lubricant, and antioxidant for later use;

S2. After pre-drying the polycarbonate at 110°C for 2.5 hours, add it to the mixer together with polyamide, thermoplastic polyester elastomer, light-absorbing slurry, lubricant and antioxidant, and control the stirring speed to 900r/min, the mixing temperature is 180°C. After stirring and mixing for 25 minutes, add it to the twin-screw extruder and extrude and granulate at 190°C to obtain the required modified polycarbonate light-absorbing transparent plastic for laser welding.

Example 5

This application provides a modified polycarbonate light-absorbing transparent plastic for laser welding, adopting the following technical solution:

A modified polycarbonate light-absorbing transparent plastic for laser welding, including 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, and 1 part of lubricant , 1 part antioxidant;

The light-absorbing slurry is prepared by the following method:

A1. Stir and mix carbon nanotubes, nanobarium titanate and nanosilver in a mass ratio of 1:0.6:0.3 to obtain a light absorber;

A2. Mix the light absorber, N’N-dimethylformamide and polyvinylpyrrolidone according to the mass ratio of 1:2.2:0.2, control the ultrasonic power to 600W, the ultrasonic time to 1h, and disperse to prepare the light-absorbing slurry;

The lubricant is pentaerythritol stearate;

The antioxidant is antioxidant 1010.

This application also provides a method for preparing modified polycarbonate light-absorbing transparent plastic for laser welding, which specifically includes the following preparation steps:

S1. In parts by weight, weigh polycarbonate, polyamide, thermoplastic polyester elastomer, light-absorbing slurry, lubricant, and antioxidant for later use;

S2. After pre-drying the polycarbonate at 115°C for 2 hours, add it to the mixer together with polyamide, thermoplastic polyester elastomer, light-absorbing slurry, lubricant and antioxidant, and control the stirring speed to 1000r /min, the mixing temperature is 175°C. After stirring and mixing for 18 minutes, add it to a twin-screw extruder and extrude and granulate at 200°C to obtain the required modified polycarbonate light-absorbing transparent plastic for laser welding.

Comparative example 1

This application provides a modified polycarbonate light-absorbing transparent plastic for laser welding, adopting the following technical solution:

A modified polycarbonate light-absorbing transparent plastic for laser welding, including the following raw materials in parts by weight: 70 parts of polycarbonate, 23 parts of polyamide, 2 parts of light-absorbing slurry, 0.5 parts of lubricant, and 0.5 parts of antioxidant;

The light-absorbing slurry is prepared by the following method:

A1. Stir and mix carbon nanotubes, nanobarium titanate and nanosilver in a mass ratio of 1:0.4:0.1 to obtain a light absorber;

A2. Mix the light absorber, N’N-dimethylformamide and polyvinylpyrrolidone according to the mass ratio of 1:1.8:0.1, control the ultrasonic power to 500W, the ultrasonic time to 2h, and disperse to prepare the light-absorbing slurry;

The lubricant is pentaerythritol stearate;

The antioxidant is antioxidant 1010.

This application also provides a method for preparing modified polycarbonate light-absorbing transparent plastic for laser welding, which specifically includes the following preparation steps:

S1. In parts by weight, weigh polycarbonate, polyamide, light-absorbing slurry, lubricant, and antioxidant for later use;

S2. After pre-drying the polycarbonate at 95°C for 2 hours, add it to the mixer together with the polyamide light-absorbing slurry, lubricant and antioxidant. Control the stirring speed to 700r/min and the mixing temperature to 195°C, stir and knead for 20 minutes, add it to a twin-screw extruder, and extrude and granulate at 150°C to obtain the required modified polycarbonate light-absorbing transparent plastic for laser welding.

Comparative example 2

This application provides a modified polycarbonate light-absorbing transparent plastic for laser welding, adopting the following technical solution:

A modified polycarbonate light-absorbing transparent plastic for laser welding, including the following raw materials in parts by weight: 93 parts of polycarbonate, 2 parts of light-absorbing slurry, 0.5 parts of lubricant, and 0.5 parts of antioxidant;

The light-absorbing slurry is prepared by the following method:

A1. Stir and mix carbon nanotubes, nanobarium titanate and nanosilver in a mass ratio of 1:0.4:0.1 to obtain a light absorber;

A2. Mix the light absorber, N’N-dimethylformamide and polyvinylpyrrolidone according to the mass ratio of 1:1.8:0.1, control the ultrasonic power to 500W, the ultrasonic time to 2h, and disperse to prepare the light-absorbing slurry;

The lubricant is pentaerythritol stearate;

The antioxidant is antioxidant 1010.

This application also provides a method for preparing modified polycarbonate light-absorbing transparent plastic for laser welding, which specifically includes the following preparation steps:

S1. Weigh the polycarbonate, light-absorbing slurry, lubricant, and antioxidant in parts by weight and set aside;

S2. After pre-drying the polycarbonate at 95°C for 2 hours, add it to the mixer together with the light-absorbing slurry, lubricant and antioxidant. Control the stirring speed to 700r/min and the mixing temperature to 195°C. , stir and knead for 20 minutes, add it to a twin-screw extruder, and extrude and granulate at 150°C to obtain the required modified polycarbonate light-absorbing transparent plastic for laser welding.

Comparative example 3

This application provides a modified polycarbonate light-absorbing transparent plastic for laser welding, adopting the following technical solution:

A modified polycarbonate light-absorbing transparent plastic for laser welding, including the following raw materials in parts 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, 0.5 part of antioxidant;

The light absorber is obtained by stirring and mixing carbon nanotubes, nano-barium titanate and nano-silver in a mass ratio of 1:0.4:0.1;

The lubricant is pentaerythritol stearate;

The antioxidant is antioxidant 1010.

This application also provides a method for preparing modified polycarbonate light-absorbing transparent plastic for laser welding, which specifically includes the following preparation steps:

S1. In parts by weight, weigh polycarbonate, polyamide, thermoplastic polyester elastomer, light absorber, lubricant, and antioxidant for later use;

S2. After pre-drying the polycarbonate at 95°C for 2 hours, add it to the mixer together with polyamide, thermoplastic polyester elastomer, light absorber, lubricant and antioxidant, and control the stirring speed to 700r/ min, the mixing temperature is 195°C. After stirring and mixing for 20 minutes, add it to a twin-screw extruder and extrude and granulate at 150°C to obtain the required modified polycarbonate light-absorbing transparent plastic for laser welding.

Comparative example 4

This application provides a modified polycarbonate light-absorbing transparent plastic for laser welding, adopting the following technical solution:

A modified polycarbonate light-absorbing transparent plastic for laser welding, including the following raw materials by weight: 70 parts of polycarbonate, 18 parts of polyamide, 5 parts of thermoplastic polyester elastomer, 0.7 parts of light absorber, 0.5 parts of lubricant, 0.5 part of antioxidant;

The light absorber is obtained by stirring and mixing carbon nanotubes, nano-barium titanate and nano-silver in a mass ratio of 1:0.4:0.1;

A2. Mix the light absorber, N’N-dimethylformamide and polyvinylpyrrolidone according to the mass ratio of 1:1.8:0.1, control the ultrasonic power to 500W, the ultrasonic time to 2h, and disperse to prepare the light-absorbing slurry;

The lubricant is pentaerythritol stearate;

The antioxidant is antioxidant 1010.

This application also provides a method for preparing modified polycarbonate light-absorbing transparent plastic for laser welding, which specifically includes the following preparation steps:

S1. In parts by weight, weigh polycarbonate, polyamide, thermoplastic polyester elastomer, light absorber, lubricant, and antioxidant for later use;

S2. After pre-drying the polycarbonate at 95°C for 2 hours, add it to the mixer together with polyamide, thermoplastic polyester elastomer, light absorber, lubricant and antioxidant, and control the stirring speed to 700r/ min, the mixing temperature is 195°C. After stirring and mixing for 20 minutes, add it to a twin-screw extruder and extrude and granulate at 150°C to obtain the required modified polycarbonate light-absorbing transparent plastic for laser welding.

Comparative example 5

This application provides a modified polycarbonate light-absorbing transparent plastic for laser welding, adopting the following technical solution:

A modified polycarbonate light-absorbing transparent plastic for laser welding, including 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, and 0.5 parts of lubricant , antioxidant 0.5 parts;

The light-absorbing slurry is prepared by the following method:

A1. Stir and mix carbon nanotubes and nanobarium titanate at a mass ratio of 1:0.5 to obtain a light absorber;

A2. Mix the light absorber, N’N-dimethylformamide and polyvinylpyrrolidone according to the mass ratio of 1:1.8:0.1, control the ultrasonic power to 500W, the ultrasonic time to 2h, and disperse to prepare the light-absorbing slurry;

The lubricant is pentaerythritol stearate;

The antioxidant is antioxidant 1010.

This application also provides a method for preparing modified polycarbonate light-absorbing transparent plastic for laser welding, which specifically includes the following preparation steps:

S1. In parts by weight, weigh polycarbonate, polyamide, thermoplastic polyester elastomer, light-absorbing slurry, lubricant, and antioxidant for later use;

S2. After pre-drying the polycarbonate at 95°C for 2 hours, add it to the mixer together with polyamide, thermoplastic polyester elastomer, light-absorbing slurry, lubricant and antioxidant, and control the stirring speed to 700r /min, the mixing temperature is 195°C. After stirring and mixing for 20 minutes, add it to a twin-screw extruder and extrude and granulate at 150°C to obtain the required 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 1-5 and Comparative Examples 1-5 of the present application were injection molded into a 100mm*100mm*2mm high-gloss plate under the same injection molding process conditions. Near-infrared projection and reflection data are collected at 960nm with a spectrophotometer, and absorbance = 100% - transmittance - reflectivity.

The injection-molded high-gloss plate and the transparent PMMA plate were alternately placed together, and irradiated with a semiconductor laser (960nm) with a beam diameter of 2mm. By controlling the laser intensity to 40W and the welding speed to 40mm/s, compare the surface conditions of the sample after welding. Saw the laser welded sample into 10mm wide strips, use a tensile testing machine to measure the tensile shear strength, and calculate the welding strength based on the tensile shear strength. The welding strength is the tensile strength/(width of the weld * width of the weld) length), the results are shown in Table 1 below:

From the data shown in Table 1, it can be seen that the modified polycarbonate light-absorbing transparent plastic for laser welding prepared in Examples 1-5 of the present application has high laser welding efficiency, high welding quality, high light absorption efficiency, and excellent overall performance.

It can be seen from the Examples and Comparative Examples 1-2 that in the polycarbonate system, the compound addition of polyamide and thermoplastic polyester elastomer can significantly improve the overall performance of welded plastics.

It can be seen from Example 1 and Comparative Examples 3-4 that making the conductive agent into a conductive slurry and then adding it to the polycarbonate system can help achieve uniform and stable dispersion of the light absorber in the polycarbonate system and prevent the light absorber from forming. Precipitation or aggregation is detected, thereby ensuring that the light absorber is fully utilized, thereby improving laser welding efficiency.

It can be seen from Example 1 and Comparative Example 5 that using a combination of carbon nanotubes, nanobarium titanate and nanosilver as the light absorber can significantly improve the light absorption efficiency and promote the welding process.

This specific embodiment is only an explanation of the present application, and it is not a limitation of the present application. After reading this specification, those skilled in the art can make modifications to this embodiment without creative contribution as needed, but as long as the rights of this application are All requirements are protected by patent law.

Claims (10)

1. A modified polycarbonate light-absorbing transparent plastic for laser welding, characterized in that it includes the following parts by weight of raw materials: 70-90 parts by weight of polycarbonate, 18-30 parts by polyamide, and 5-10 parts by weight of thermoplastic polyester elastomer. parts, 2-5 parts of light-absorbing slurry, 0.5-1 part of lubricant, 0.5-1 part of antioxidant. 2. The modified polycarbonate light-absorbing transparent plastic for laser welding according to claim 1, characterized in that it includes the following parts by weight of raw materials: 75-85 parts by weight of polycarbonate, 22-26 parts by polyamide, and thermoplastic polyester. 6-8 parts of elastomer, 2.5-4.5 parts of light-absorbing slurry, 0.6-0.8 parts of lubricant, and 0.6-0.8 parts of antioxidant. 3. The modified polycarbonate light-absorbing transparent plastic for laser welding according to claim 1, characterized in that it includes the following parts by weight of raw materials: 80 parts of polycarbonate, 24 parts of polyamide, and 7 parts of thermoplastic polyester elastomer. , 3.5 parts of light-absorbing slurry, 0.7 parts of lubricant, and 0.7 parts of antioxidant. 4. The modified polycarbonate light-absorbing transparent plastic for laser welding according to claim 1, characterized in that the light-absorbing slurry is made of a light absorbing agent, N'N-dimethylformamide and polyvinylpyrrolidone mixed and then ultrasonicated. obtained by dispersion. 5. The modified polycarbonate light-absorbing transparent plastic for laser welding according to claim 4, wherein the light absorbing agent includes carbon nanotubes and nanometer barium titanate with a mass ratio of 1:0.4-0.6:0.1-0.3. and nanosilver. 6. The modified polycarbonate light-absorbing transparent plastic for laser welding according to claim 4, wherein the mass ratio of the light absorbing agent, N'N-dimethylformamide and polyvinylpyrrolidone is 1:1.8 -2.2:0.1-0.2. 7. The modified polycarbonate light-absorbing transparent plastic for laser welding according to claim 4, characterized in that the ultrasonic power is 500-600W and the ultrasonic time is 1-2 h. 8. The modified polycarbonate light-absorbing transparent plastic for laser welding according to claim 1, wherein the lubricant is at least one of pentaerythritol stearate, zinc stearate, and calcium stearate. . 9. The modified polycarbonate light-absorbing transparent plastic for laser welding according to claim 1, wherein the antioxidant is at least one of antioxidant 1010, antioxidant 1076, and antioxidant 168 . 10. A method for preparing the modified polycarbonate light-absorbing transparent plastic for laser welding according to any one of claims 1 to 9, characterized in that it specifically includes the following preparation steps: S1. In parts by weight, weigh polycarbonate, polyamide, thermoplastic polyester elastomer, light-absorbing slurry, lubricant, and antioxidant for later use; S2. After pre-drying the polycarbonate, add it to the mixer together with polyamide, thermoplastic polyester elastomer, light-absorbing slurry, lubricant and antioxidant, stir and mix, then extrudate and granulate to obtain the desired result. Modified polycarbonate light-absorbing transparent plastic for laser welding.