I. Basic Properties

1. Mechanical Properties:

High Impact Strength: PC/ABS alloy has extremely high impact strength, thanks to the high toughness of ABS and the high strength of PC.

High Hardness and High Toughness: PC/ABS material possesses high strength, high hardness, and high toughness, making it resistant to deformation or cracking under external forces.

Good Dimensional Stability: Due to the addition of PC, PC/ABS alloy maintains dimensional stability under temperature changes and is not easily deformed.

2. Heat Resistance:

High Temperature Resistance: PC/ABS alloy has excellent heat resistance, with a Vicat softening temperature ranging from 112°C to 142°C, allowing it to maintain stable performance in high-temperature environments.

Melting Point and Heat Distortion Temperature: The melting point of PC/ABS is around 135°C, and its heat distortion temperature ranges from 80°C to 125°C, suitable for various processing conditions.

3. Electrical Properties:

Good Electrical Insulation: PC/ABS alloy has excellent electrical insulation properties, making it suitable for applications requiring electrical insulation.

4. Chemical Stability:

Resistance to Acids and Bases:

PC/ABS alloy has a certain resistance to some common acids and bases. For example, in low-concentration inorganic acids (such as hydrochloric acid, sulfuric acid, etc.) and bases (such as sodium hydroxide) solutions, it can maintain good chemical stability without significant chemical reactions such as dissolution, deformation, or discoloration. However, when the concentration of acids or bases is too high, they may corrode the alloy, leading to a decline in performance.

Resistance to Organic Solvents

For certain organic solvents, the tolerance of PC/ABS alloys varies depending on the type of solvent. It has good resistance to non-polar organic solvents (such as gasoline, kerosene, etc.), showing no obvious swelling or dissolution when in contact with these solvents. However, for some solvents with stronger polarity (such as ketones, esters, etc.), some degree of swelling may occur, which can affect its dimensional stability and mechanical properties.

5. Processing Performance:

Easy to Process: PC/ABS alloys have good processing fluidity and can be molded into various product shapes through injection molding, extrusion, blow molding, and other methods.

Moldability: The ABS component enhances the moldability of the alloy, making it easy to shape during injection molding and providing a smooth surface.

6. Electrical Properties:

Flame Retardant: PC/ABS alloys can improve their flame retardancy by adding flame retardants, making them less likely to catch fire under fire conditions.

7. Other Characteristics:

UV Resistance: PC/ABS alloys have good UV resistance, suitable for applications exposed to sunlight for long periods.

Non-toxic and Odorless: PC/ABS materials are non-toxic and odorless, making them suitable for applications involving food contact.

II. Synthesis Methods

Blending and polymerization are the two main methods for preparing PC/ABS alloys. These methods differ in principles, processes, and the performance of the final products.

1. Blending Method

The blending method involves mixing PC (polycarbonate) and ABS (acrylonitrile-butadiene-styrene copolymer) in certain proportions and preparing PC/ABS alloys through high-temperature melt blending. The specific steps are as follows:

Weighing: Weigh PC and ABS according to the required ratio.

Melt Blending: In a molten state, thoroughly mix the materials using an extruder or mixer.

Cooling and Pelletizing: Cool the mixture and cut it into pellets to obtain the PC/ABS alloy.

The advantage of this method is its simplicity and low equipment requirements, making it suitable for large-scale production. However, the drawback of the blending method is that it may result in compatibility issues between the two materials, affecting the mechanical properties and thermal stability of the alloy.

2. Aggregation law

The polymerization method is to directly synthesize PC/ABS copolymers through polymerization reactions. The specific steps are as follows:

Monomer preparation: Polymerization reactions are carried out using corresponding monomers (e.g., carbonate, acrylonitrile, butadiene, styrene).

Control reaction conditions: Adjust the molecular structure and properties of polymers by controlling reaction conditions (temperature, pressure, catalyst, etc.).

The advantage of polymerization is that it can obtain PC/ABS copolymers with a more uniform molecular structure, thereby improving the overall properties of the alloy. For example, by adjusting the reaction conditions, the mechanical properties, thermal stability, and processability of the alloy can be optimized.

Performance comparison:

In practical applications, PC/ABS alloys prepared by blending and polymerization have their own advantages and disadvantages. PC/ABS alloys prepared by blending method have high production efficiency and lower cost, but may affect the compatibility and mechanical properties of the alloy. PC/ABS alloys prepared by polymerization have better molecular structure uniformity and comprehensive properties, but the production cost is higher and the process is complex.

3. Identification

POLYMER ALLOY

1. New method: rub with ethyl acetate, ABS does not make silk, HIPS will be silky, but it only refers to pure ones.

2. Common methods: ABS, PS identification methods are many kinds, as far as ABS is concerned, the surface brightness is good, the toughness is better than PS, after the fire will have dense small holes, the taste has a faint sweetness; PS is divided into three types: GPPS, HIPS, EPS, more brittle, more transparent products, HIPS brightness is average, toughness is a little inferior to ABS, the surface is bright after fire, there is a styrene smell. The cross-section of HIPS is whitish, but GPPS does not, and EPS is mainly used for foams.

TV shell material, there are ABS, HIPS, generally according to the surface characteristics, physical characteristics to distinguish, the brightness of the surface is generally ABS, when broken with pliers, ABS is better than HIPS, its hardness is higher, it needs to be stronger, and then according to the flame and taste to distinguish.

How much of the commonly mentioned PC/ABS alloy does it account for?

The proportion of PC and ABS in PC/ABS alloys does not have a fixed value, but is determined according to different usage requirements. Here's a detailed analysis of the ratio of PC and ABS in PC/ABS alloys:

1. Common ratio

70/30: This is the more common PC/ABS alloy ratio on the market, and the alloy under this ratio performs well in terms of comprehensive performance, taking into account the requirements of strength, heat resistance and toughness.

50/50: In some specific application scenarios, the 50/50 ratio is also employed to achieve a specific performance balance.

Between 30/70 and 70/30: In addition to the above two common ratios, the ratio of PC/ABS alloy can also be adjusted within this range to meet the needs of different customers.

2. The impact of proportion on performance

PC content: When the PC content is high, the strength and heat resistance of the alloy are enhanced. For example, when the PC/ABS ratio is 80/20, the impact strength may be maximum. However, too high a PC content may lead to a decrease in the toughness of the alloy.

ABS Content: The addition of ABS can improve the toughness and impact resistance of the alloy. When the ABS content is higher, the surface appearance of the alloy will be better. At the same time, the right amount of ABS can also improve the processability and fluidity of the alloy.

3. Selection of the best ratio

The selection of the optimal ratio depends on the specific requirements and application scenarios of the product. For example, for products that require high strength and heat resistance, you can choose alloys with higher PC content; For products that require good toughness and impact resistance, you can choose alloys with higher ABS content. In addition, it is also necessary to consider the impact of factors such as product thickness and test temperature on the alloy's properties.

To sum up, the ratio of PC and ABS in PC/ABS alloy should be determined based on specific product requirements and application scenarios. In the actual production process, the performance and service life of the alloy can be optimized by adjusting the ratio and adding auxiliary agents.

How does the heat resistance of PC/ABS alloys change with temperature?

The heat resistance of PC/ABS alloy mainly depends on its composition ratio and production process. Typically, the alloy's heat resistance temperature range is between 100~120°C. When the PC content is as high as 85%, the long-term use temperature can be maintained at about 90-95°C. However, adding flame retardants can reduce the thermal deformation temperature of the material, affecting its temperature resistance.

PC/ABS alloys maintain strength and stiffness in high-temperature environments, making them suitable for applications that withstand high-temperature conditions. For example, this heat resistance is crucial in areas of the car with high heat exposure (e.g., air conditioning vents, window controllers, etc.). In contrast, ABS material becomes brittle at low temperatures, leading to a significant decrease in impact and tensile strength. The heat deformation temperature of pure ABS raw materials is between 80°C-85°C, while the heat deformation temperature of flame retardant ABS drops to 70°C-75°C due to the addition of flame retardants. Therefore, the heat resistance of PC/ABS alloys varies with temperature variations, depending on the ratio of PC to ABS and the production process.

What is the machining performance of PC/ABS alloy under different processing conditions?

The injection molding temperature and mold temperature of PC/ABS alloy have a significant impact on its impact properties. Matte PC/ABS has the best impact performance at an appropriate injection temperature of 240°C and a mold temperature of 80°C. Temperatures that are too high or too low can reduce the impact strength. Injection pressure (2.6-6.1 MPa) and velocity (13.9-32.3 g/s) have little effect on impact performance within the appropriate range, but the appearance quality is guaranteed. Before processing, it must be dried, the humidity should be less than 0.04%, and the recommended condition is 2~4 hours at 90~110°C. The melting temperature is generally between 230~300°C, and the mold temperature is between 50~100°C.

The vacuum process has little impact on mechanical properties, and the effect of the pre-drying + 1-stage vacuum process is equivalent to that of the undried + 2-stage vacuum process, and no pre-drying step is required. SMA-700 had the best effect on improving the impact strength of the low-temperature notch, while EMA had a better effect on improving the impact strength of the notch at thermal aging. During the electroplating process, the roughening effect is affected by temperature and time, and the optimal condition is 64°C for 14 minutes.

How to improve the flame retardant performance of PC/ABS alloy by adding flame retardants?

To improve the flame retardant properties of PC/ABS alloys, it can be achieved by adding different types of flame retardants. Here are several effective flame retardants and their mechanisms of action:

Phosphorus-containing flame retardants: e.g. triphenyl phosphate (TPP), resorcinol-bis(diphenyl phosphate) (RDP), and bisphenol A-bis(diphenyl phosphate) (BDP). These flame retardants can significantly improve the flame retardant properties of PC/ABS alloys. Studies have shown that BDP is the best and can significantly improve the oxygen index and flame retardant level of the alloy.

Silicon-based flame retardants: Silicon-based flame retardants such as PSBPBP and DOPO-containing silicon flame retardants (such as DPA-SiN and DVN) can form a dense expanded carbon layer during the combustion process, insulating the transfer of heat and combustible gases, thereby improving the flame retardant performance of the material. For example, the addition of DPA–SiN with a mass fraction of 30% can increase the oxygen index of PC/ABS alloys from 21% to 27% and reduce the heat release rate and total release calorific value.

Brominated Flame Retardants: Brominated flame retardants, such as decabromodiphenyl ether and Sb2O3, have efficient flame retardant effects, but their decomposition process releases corrosive hydrogen bromide gas, so they need to be used with caution in some applications. However, they do significantly improve the flame retardant properties of PC/ABS alloys.

Halogen-free flame retardants: Halogen-free flame retardants such as MBS (melamine formaldehyde resin) not only enhance the alloy's flame retardant properties but also improve its mechanical properties. For example, the addition of MBS increases the oxygen index from 21 to 30, and the overall performance of the alloy is excellent.

Nano flame retardant technology: Using nanomaterials as flame retardants can further improve the flame retardant effect of PC/ABS alloys. Nano-flame retardants enhance the flame resistance of materials by introducing flame retardant groups into polymer materials.

What are the specific aspects of the electrical insulation performance of PC/ABS alloy?

Good electrical insulation properties: PC/ABS alloys have excellent electrical insulation properties and are suitable for electronic and electrical equipment enclosures and components. This material is widely used in the field of electronics and electrical equipment due to its ability to provide reliable electrical isolation against current leakage or short circuits.

Arc resistance: PC/ABS alloy not only has good insulation properties, but also has arc resistance, which means it can maintain stable electrical performance in high-voltage environments and is not easily broken down by arcs.

Low impact of temperature, humidity and frequency: ABS plastic has good electrical insulation and is almost unaffected by temperature, humidity and frequency, and can be used in most environments. This allows PC/ABS alloys to maintain stable electrical insulation properties under various environmental conditions.

High Impact Resistance and Dimensional Stability: PC/ABS alloy combines the advantages of PC and ABS, offering high impact strength and high dimensional stability. These properties ensure that the material maintains good electrical insulation properties when subjected to mechanical stress.

Excellent comprehensive performance: PC/ABS alloy not only has good electrical insulation properties, but also has high impact resistance, high heat resistance, flame retardant and other characteristics. These combined properties make PC/ABS alloys more reliable and safe in practical applications.

4. Application fields

1. Automotive Sector:

Application scenarios: PC/ABS alloy is often used to manufacture automotive interior and exterior trim, dashboards, door handles, etc.

Function: Its high impact strength, good heat resistance, and weather resistance ensure the stability and safety of automotive components in complex and changeable driving environments. At the same time, the processability and good surface gloss of PC/ABS alloy also improve the aesthetics of the car.

2. Electronic and electrical field:

Application scenarios: PC/ABS alloy is widely used in the shells, brackets, and internal components of electronic products such as smartphones, tablets, laptops, and TVs.

Function: Its excellent electrical insulation, good dimensional stability, and chemical resistance ensure the stable operation and long-term reliability of electronic products.

3. Communication field:

Application scenarios: PC/ABS alloy is used in mobile phone base station shells, communication equipment cabinets, router shells, switch shells, etc.

Function: Good heat resistance and weather resistance ensure the signal transmission efficiency and long-term stability of communication equipment.

4. Medical Device Field:

Application scenarios: PC/ABS alloy is used to manufacture medical device shells, handles, liquid reservoirs, etc.

Function: Its non-toxic, odorless, and easy-to-clean characteristics, as well as good impact resistance and heat resistance, ensure the hygiene safety of medical devices and the comfort of patient use.

5. Other fields:

Application scenarios: PC/ABS alloy is also used to make safety helmets, sports equipment, toys, etc.

Function: Its high impact strength and good wear resistance provide reliable protection for these products.

5. Development trend

The field of PC/ABS alloys is constantly innovating, ensuring a wide range of applications and safety through patent protection (technological innovation and patent protection). It is expected that its market demand will continue to grow by 2030, especially in China and globally (market demand growth). The alloy is widely used in automobiles, electronic appliances, communications, and medical devices, and with the development of new energy vehicles, the demand for components such as module housings has increased (expansion of application fields).

PC/ABS alloys have high impact strength, heat resistance, and dimensional stability, and maintain good mechanical properties at extreme temperatures, making them suitable for low-temperature environments (improved performance). By changing the material structure and process, high-performance alloys such as high-toughness PBT/PC/ABS have been developed to provide better material options for high-end automotive bumpers and other fields (development of innovative materials).

To sum up, the future development trend of PC/ABS alloys will focus on technological innovation, market demand growth, application field expansion and performance improvement, with broad prospects.