Flame Retardant PPS LGF Filling Long Glass Fiber Composite Plastic

PPS material

Polyphenylene Sulfide (PPS) is also known as polyphenylene sulfide and polyphenylene sulfide. Polyphenylene sulfide (PPS) is composed of alternating units of paraphenylene and sulfur bonding, molecular chemical structure contains repeated structural units of phenylene sulfide, PPS plastic is composed of benzene ring and sulfur atoms alternately arranged into polymer linear rigid molecular structure, is a simple chemical structure of crystalline high-temperature resistance and high-performance engineering plastics.

PPS plastic is a high strength, high rigidity and opaque polymer. Polyphenylene sulfide (PPS) is a kind of high performance thermoplastic engineering plastics gradually applied to industrial products, with excellent heat resistance, flame retardant, insulation, its strength and hardness are higher than the general engineering plastics, can be processed by a variety of molding methods, and can be precision molding.

At the same time, polyphenylene sulfide (PPS) has excellent compatibility with inorganic filler, reinforced fiber and other polymer materials, so it can be made into different reinforced filling grade plastic formula and polymer alloy mixed plastics. Polyphenylene sulfide (PPS) is a cost-effective high performance engineering plastics in the industry so far, has become one of the most used in high performance engineering plastics. Mainly used to replace metal and thermosetting resin, is widely used in various fields.

The main characteristics of PPS plastics

PPS plastic is a thermoplastic with crystallization and high temperature resistance. PPS can maintain ideal mechanical strength and chemical corrosion resistance even at temperatures above 200℃. In addition to low water absorption, PPS plastics offer excellent dimensional stability and excellent electrical properties. PPS plastics maintain very stable chemical properties even at high temperature. The characteristics of PPS high performance engineering plastics are as follows:

• High heat resistant plastic that can be used continuously at more than 200℃.
• Maintain high rigidity and strength in a wide temperature range.
• The resin itself is inherently UL94 V-0 rated for flame retardancy.
• Excellent dimensional stability in a wide range of operating conditions.
• Chemical resistance second only to fluorine series resins.
• Excellent electrical performance under high temperature, high humidity and high frequency environment.
• Can carry out complex high precision molding.

The characteristics of the above PPS plastics are described in detail as follows:

• PPS excellent heat resistance:
The melting point of crystalline PPS plastic is more than 280℃, the thermal deformation temperature (HDT) is more than 260℃, and the long-term use temperature is 220~240℃. Degradation occurs at 700℃ in the air environment, and PPS can still maintain 40% weight at 1000℃ in the inert gas environment. The short-term heat resistance and long-term continuous use of thermal stability are better than all the current engineering plastics. PPS is a specially modified plastic type, and the thermal deformation temperature can reach more than 350℃. So it's an excellent high-temperature structural material. The soldering resistance of PPS is much higher than other engineering plastics, making it suitable for the production of electronic and electrical components. Such thermal properties are rare even in thermosetting plastics. In addition, PPS itself has good insulation, but by adding appropriate filler material, high thermal conductivity of PPS composites can be prepared.

• PPS itself is flame retardant:
The flame retardancy of polyphenylene sulfide can reach UL94-V0 grade, oxygen consumption index (LOI)>57%. The chemical structure of polyphenylene sulfide makes it have good refractory performance, without adding flame retardant.

• PPS excellent mechanical properties:
PPS strong rigidity, high surface hardness, Rockwell hardness >100HR, tensile strength >170MPa, bending strength >220MPa, notched impact strength >16MPa, bending modulus >3.5×104MPa, with excellent creep resistance and fatigue resistance.

• PPS excellent resistance to chemical drugs:
PPS has excellent resistance to chemical corrosion, stable resistance to organic alcohols, ketones, acids, esters, phenols, aliphatic hydrocarbons, aromatic hydrocarbons, chlorinated hydrocarbons and inorganic acids, bases, salts, etc. PPS is insoluble in any organic solvent below 200℃ except for chlorinated biphenyls and strong nitric acid.

• PPS dimensional stability is excellent:
PPS forming shrinkage rate is very low (about 0.2~0.5%), water absorption rate is less than 0.05%, linear thermal expansion coefficient (3~5×10-5/° C) is also small. It still shows good dimensional stability under high temperature and high humidity conditions. Therefore, it has a wide range of uses in machinery, chemical industry, instruments, meters and other aspects.

• PPS excellent electrical performance:
PPS in high temperature, high humidity, high frequency conditions, still has excellent electrical performance, its volume resistivity is 1× 1016Ω.cm, surface resistivity is 1× 1015Ω, electrical strength >18KV/mm.

• PPS resists high-energy radiation:
PPS has good radiation resistance to UV and cobalt-60 rays, and radiation resistance can reach 1×108Gy, which is incomparable to other engineering plastics. PPS is the only ideal material for products with high demand for radiation resistance in electronic, electrical, mechanical and other fields, especially in the military industry.

• PPS has good processing performance:
The melt viscosity of PPS resin is low, the fluidity is good, and it is easy to impregnate with glass fiber, so it is easy to fill the filler. The glass fiber or inorganic filler prepared by it is used to enhance the injection granular material, which has extremely high scalability, impact resistance, bending resistance and ductility. Above its melting point can be formed uniformly.

• PPS has good adhesion with metal and non-metal:
PPS especially for glass, aluminum, titanium, stainless steel and other materials with very high bonding strength, adhesion force reached 1 level; It has good bonding property to glass and is very suitable for lining chemical equipment.

Product application considerations of PPS plastics

The reason why PPS plastic is chosen to produce plastic parts is usually taken into account the two important properties of PPS, PPS has excellent chemical resistance (resistance to chemicals) and PPS plastic has a high thermal deformation temperature; The UL index temperature of PPS (UL temperature index)- (generally this temperature can also be regarded as the continuous usable temperature) can exceed about 105° C, the continuous use temperature of plastic materials can be higher than PPS plastic, in addition to thermosetting plastic, is a few high unit price of high-performance engineering plastics, However, its price is more than 10~20 times higher than that of PPS plastic.

PPS plastic because in recent years the unit price has been greatly reduced, PPS can be said to be the lowest in high performance engineering plastic unit price, and has been quite close to the price of widely used engineering plastic. So in use, it is the most widely accepted plastic in high performance engineering plastics. PPS plastic currently available commercial material color is not much, mainly partial earth color and brown, black and dark blue.

Frequently asked questions

1. After the long glass fiber reinforced, the glass fiber content of the material increases. The resin fat solubility reduces the flow performance, and the injection pressure is much higher than that without the glass fiber. How to solve the problem of poor molding and lack of fluidity in injection molding?

In the early stage, we must understand the size of the customer's product structure firstly, whether the number of holes and the gate will affect the molding of the product? Whether the material fluidity will affect the injection molding temperature, and whether the setting of injection pressure and mold temperature, and whether the setting of injection pressure and mold temperature setting are reasonable etc.