Product Details

CasNo： 9009-54-5

MF： C?H?N?O

Appearance： powder

Delivery Time： 15 days

Packing： 25kg/bag

Purity： 30%

1. General Information

Polyphenylene Sulfide (PPS), with the chemical formula (C?H?S)?, is a high - performance thermoplastic resin. It features a molecular structure where benzene rings and sulfur atoms are arranged alternately in the main chain. This unique structure endows PPS with a series of outstanding properties, making it a popular choice in various industrial fields.

2. Physical and Chemical Properties

2.1 Physical Properties

• Appearance: Usually presented as white to slightly yellowish powder.

• Density: Approximately 1.36 g/mL at 25 °C. This relatively high density contributes to its good mass - related performance in applications.

• Melting Point: The melting point of PPS is around 280 °C. Such a high melting point enables it to maintain its shape and integrity under high - temperature conditions.

• Glass Transition Temperature: The glass transition temperature (Tg) is about 150 °C. Below this temperature, PPS shows glass - like behavior, while above it, it exhibits more rubber - like characteristics.

• Crystallinity: PPS is a crystalline polymer. The degree of crystallinity can affect its mechanical and thermal properties. For example, higher crystallinity often leads to increased mechanical strength and heat resistance.

2.2 Mechanical Properties

• High Strength and Rigidity: PPS has a high tensile strength, which can reach up to 70 MPa (yield) in its unmodified form. When reinforced with glass fibers or other fillers, this value can be significantly increased, sometimes up to several times. Its flexural modulus is also high, typically around 3300 MPa (for a 50.0 - mm span), which indicates excellent stiffness. For instance, in applications such as manufacturing precision gears, its high rigidity ensures accurate transmission and low deformation under load.

• Good Creep Resistance: PPS shows excellent creep resistance, meaning that under long - term loading, its deformation is minimal. This property is crucial in applications where dimensional stability over time is required, like in the production of mechanical parts in high - temperature and high - load environments.

• High Hardness and Wear Resistance: The material has a relatively high hardness, which, combined with its good wear resistance, makes it suitable for applications involving friction and wear, such as bearings and seals. For example, in a pump, PPS - made bearings can withstand continuous rotation and friction, reducing the need for frequent replacements.

• Low Impact Strength (but can be improved): In its pure form, PPS has a relatively low impact strength. However, through methods such as adding toughening agents or using specific composite technologies, its impact resistance can be effectively enhanced.

2.3 Thermal Properties

• Excellent Heat Resistance: PPS has outstanding heat resistance. It can be continuously used in the temperature range of 200 - 220 °C, and in short - term, it can endure temperatures as high as 260 °C without significant degradation. This makes it an ideal material for applications in high - temperature environments, such as in the automotive engine compartment, where components need to withstand high temperatures generated during engine operation.

• Low Thermal Expansion Coefficient: PPS has a low coefficient of thermal expansion, which means that its dimensional change with temperature variation is small. This property ensures dimensional stability in applications where temperature fluctuations occur, like in electronic devices that may be exposed to different environmental temperatures.

2.4 Chemical Properties

• High Chemical Resistance: PPS exhibits excellent chemical resistance. It is stable in the presence of most acids, esters, ketones, aldehydes, phenols, aliphatic hydrocarbons, aromatic hydrocarbons, and chlorinated hydrocarbons. For example, in chemical processing plants, PPS - lined pipes can resist the corrosion of various chemical media, ensuring long - term and reliable operation of the pipeline system. However, it is not resistant to chlorinated biphenyls, oxidizing acids (such as concentrated sulfuric acid, concentrated nitric acid), oxidants, and substances like hydrogen peroxide and sodium hypochlorite.

• Good Solvent Resistance: It is insoluble in most common solvents at room temperature. Even at elevated temperatures, it shows high resistance to solvent penetration, which is beneficial in applications where contact with solvents is inevitable, such as in the production of coatings that need to resist chemical solvents.

2.5 Electrical Properties

• High Insulation Performance: PPS has high volume resistivity, surface resistivity, and breakdown voltage. Its volume resistivity can reach 1.0×10¹? - 1.0×10¹? ohm - cm, and surface resistivity can be 1.0×10¹² - 1.0×10¹? ohm. These properties make it an excellent insulating material in the electronics industry. For example, it is widely used in the production of electrical connectors, sockets, and insulation parts of motors.

• Low Dielectric Constant and Loss Tangent: PPS has a relatively low dielectric constant (usually around 3.0 - 3.5 at 1 MHz) and dielectric loss tangent. Moreover, these electrical properties remain stable over a wide range of frequencies, temperatures, and humidities. This stability is crucial for applications in high - frequency electronic devices, such as in the manufacturing of printed circuit boards where stable electrical performance is required.

2.6 Flame - Retardant Properties

PPS is inherently flame - retardant without the need for additional flame - retardant additives in most cases. Its oxygen index is as high as 44% or more, which means it is difficult to burn in air. When exposed to an open flame, it can self - extinguish quickly after the flame source is removed. This property makes it highly suitable for applications where fire safety is a concern, such as in the production of electronic device housings and components in the aerospace industry.

3. Production Process

3.1 Sodium Sulfide Method

• Reaction Principle: This is one of the most common industrial production methods. It involves the polycondensation reaction of sodium sulfide (Na?S) and p - dichlorobenzene (C?H?Cl?) in a polar solvent. The chemical reaction equation is: nNa?S + nC?H?Cl? → (C?H?S)? + 2nNaCl.

• Process Flow: First, high - purity sodium sulfide is dehydrated to remove water, which is crucial as water can affect the reaction rate and product quality. Then, it is mixed with p - dichlorobenzene in a polar solvent such as N - methyl - 2 - pyrrolidone (NMP). The reaction mixture is heated to a certain temperature (usually around 220 - 250 °C) under pressure and stirred continuously. After the reaction is completed, the product is separated from the reaction mixture through a series of processes, including filtration to remove solid by - products like sodium chloride, and then washing and drying to obtain pure PPS resin.

• Advantages and Disadvantages: The advantage of this method is that the raw materials are relatively inexpensive and easily available. The process is relatively simple and has been well - established, resulting in stable product quality and high yields. However, there are also some drawbacks. The preparation of high - purity sodium sulfide with strict moisture control is difficult. The dehydration process of sodium sulfide requires additional energy consumption. And the overall process has a relatively long production cycle.

3.2 Sulfur Solution Method

• Reaction Principle: In this method, sulfur (S) and p - dichlorobenzene are used as raw materials. The reaction occurs in a polar solvent at a certain temperature and pressure. The sulfur first reacts with the solvent to form an active sulfur species, which then reacts with p - dichlorobenzene to form PPS.

• Process Flow: High - purity sulfur is first dissolved in a polar solvent such as N - methyl - 2 - pyrrolidone. Then, p - dichlorobenzene is added to the solution. The reaction system is heated to a temperature in the range of 175 - 250 °C under normal pressure or slightly increased pressure. During the reaction, appropriate reducing agents and auxiliaries may be added to promote the reaction and control the reaction rate. After the reaction, the product is separated and purified through similar processes as in the sodium sulfide method, including filtration, washing, and drying.

• Advantages and Disadvantages: The advantages of this method include high - purity raw materials, which can lead to high - quality products. The reaction cycle is relatively short compared to some other methods, and the production cost can be relatively low. However, the purification of sulfur is technically challenging. The addition of reducing agents and auxiliaries increases the complexity of the reaction system and may result in more by - products.

3.3 Oxidative Polymerization Method

• Reaction Principle: This method uses diphenyl disulfide as the raw material. In the presence of an oxygen or air oxidant and an acetylacetone catalyst, oxidative polymerization occurs to form PPS. The reaction mechanism involves the activation of the sulfur - sulfur bond in diphenyl disulfide by the catalyst and the subsequent reaction with oxygen to form the PPS polymer chain.

• Process Flow: Diphenyl disulfide is dissolved in a suitable solvent. Then, oxygen or air is introduced into the reaction system, and the acetylacetone catalyst is added. The reaction is carried out at a specific temperature and pressure. After the reaction, the product is separated from the reaction mixture through methods such as precipitation, filtration, and washing.

• Advantages and Disadvantages: The advantages of this method are high product yield and extremely high product purity. There is no cyclization, disproportionation, or cross - linking phenomenon, and no by - product salts are generated, which simplifies the post - treatment process. However, currently, the molecular weight of the products obtained by this method is relatively low, resulting in low viscosity and poor processing performance.

3.4 Hydrogen Sulfide Method

• Reaction Principle: This method uses hydrogen sulfide (H?S), sodium sulfide, and p - dichlorobenzene as raw materials. In the presence of an alkali metal salt as an auxiliary agent and in a polar solvent, polycondensation occurs to form PPS. The reaction involves the reaction of hydrogen sulfide and sodium sulfide to form an active sulfur source, which then reacts with p - dichlorobenzene.

• Process Flow: Hydrogen sulfide gas is first introduced into a solution containing sodium sulfide and an alkali metal salt in a polar solvent. After the formation of the active sulfur source, p - dichlorobenzene is added. The reaction is carried out at a certain temperature and pressure. After the reaction is completed, the product is separated and purified through processes such as filtration, washing, and drying.

• Advantages and Disadvantages: The advantage of this method is that the by - products are relatively few, and the linearity of the product is high, resulting in good product quality. However, the process flow is complex, requiring high - end equipment. And the waste generated during the process may cause significant environmental pollution if not properly treated.

4. Application Areas

4.1 Electronic and Electrical Field

• Electrical Components: PPS is widely used in the production of various electrical components. For example, it is used to make high - voltage components, housings, sockets, and terminals in televisions and computers. Its excellent electrical insulation properties ensure the safe operation of these components, and its high heat resistance can withstand the heat generated during the operation of electrical devices. In the case of motor starting coils, PPS can provide good insulation and heat resistance, improving the efficiency and service life of the motor.

• Insulation Materials: PPS can be made into F - class insulating films and other insulation materials. These materials have high insulation performance and can maintain stable electrical properties under high - temperature and high - humidity environments. They are widely used in transformers, capacitors, and other electrical equipment.

4.2 Automotive Industry

• Engine - related Components: In traditional internal combustion engine vehicles, PPS is suitable for manufacturing components such as exhaust gas recirculation valves, water pump impellers, carburetors, exhaust devices, and exhaust gas regulating valves. Its high heat resistance allows these components to withstand the high - temperature environment in the engine compartment. In new energy vehicles, PPS is used in the three - electric drive module (motor, controller, and battery), power control module, and fuel system. For example, PPS - made parts in the battery module can provide good electrical insulation and heat resistance, ensuring the safety and stability of the battery.

• Lighting and Other Parts: PPS is also used in the production of automotive lighting system components, such as lamp housings and reflectors. Its high - temperature resistance and good dimensional stability ensure the normal operation of the lighting system under different working conditions. In addition, it can be used to make bearings, sensors, and other parts in the vehicle, taking advantage of its excellent mechanical and chemical properties.

4.3 Mechanical Industry

• Mechanical Parts: PPS is an ideal material for manufacturing various mechanical parts, such as bearings, pumps, valves, pistons, and precision gears. Its high hardness, wear resistance, and good mechanical strength make these parts have a long service life and high - precision operation. For example, in a high - pressure pump, PPS - made valves can withstand high - pressure fluid impact and have good sealing performance.

• Office Equipment Parts: It is also used in the production of parts for office equipment such as copiers, cameras, and computers. In copiers, PPS can be used to make parts such as rollers and gears, which need to have high precision and wear resistance to ensure the normal operation of the copier.

4.4 Chemical Industry

• Corrosion - resistant Equipment: PPS is used to make valves, pipes, fittings, gaskets, and submersible pump impellers that are resistant to acids and alkalis. In chemical plants, these parts are often in contact with corrosive chemical media, and PPS's excellent chemical resistance can effectively prevent corrosion, ensuring the normal operation of the equipment and reducing maintenance costs. For example, PPS - lined pipes can transport corrosive liquids such as strong acids and alkalis without being corroded.

4.5 Environmental Protection Field

• Filter Materials: PPS fibers are made into filter materials, which are widely used in industries such as smelting, chemical industry, thermal power generation, and waste incineration. These filter materials can effectively filter out dust and harmful substances in high - temperature and harsh environments. For example, in a coal - fired power plant, PPS filter bags can filter out fly ash at high temperatures, reducing air pollution.

4.6 Tableware Field

• Food - contact Products: PPS can be used to make tableware such as chopsticks, spoons, and bowls. Because it is non - toxic and safe, it can directly contact food. Its high - temperature resistance also allows it to be used in high - temperature sterilization processes, ensuring food safety and hygiene.

5. Packaging and Storage

5.1 Packaging

PPS resin is usually packaged in moisture - proof paper bags or plastic - lined paper bags to prevent moisture absorption during storage and transportation. For large - scale industrial use, it may be packaged in 25 - kg bags or in larger bulk containers. In some cases, it can also be packaged in sealed drums to ensure better protection of the product.

5.2 Storage

It should be stored in a dry, cool, and well - ventilated warehouse. Avoid direct sunlight and high - temperature environments. The storage temperature is preferably controlled below 30 °C, and the relative humidity is maintained below 60%. When stored properly, PPS resin can maintain its quality and performance for a long time. It should also be stored separately from oxidizing agents, strong acids, and other chemicals that may react with it.