How to improve plastic scratch resistance, wear resistance(plastic products)

1

Select the right matrix resin

Usually ultra-high molecular weight polyethylene (PE-UHWM) is one of the most wear-resistant plastics, and the selection of PE-U·HWM can simply improve the wear resistance of the material. In addition, high crystallization, high regularity of the plastic is more wear-resistant, high hardness of the plastic is more wear-resistant, such as polystyrene composed of large molecules such as benzene rings do not wear. In polypropylene (PP) modification, polyolefin elastomer (POE), ethylene propylene terene rubber (EPDM), thermoplastic dynamic vulcanized rubber (TPV) (such as dynamic vulcanized PP/EPDM) is usually used to toughen PP, and the addition of elastomers generally leads to a decline in scratch resistance, so it is very important to choose the appropriate elastomer. The order of scratch resistance is as follows: TPV > EPDM > POE.

2

Packing with good wear resistance

(1) Molybdenum disulfide.

Molybdenum disulfide is a wear-resistant additive mainly used in nylon plastics. Molybdenum disulfide acts as a crystallizing agent to increase the crystallinity of nylon, so that the nylon material produces a harder and more wear-resistant surface. Molybdenum disulfide has a high affinity for metal, once adsorbed on the metal surface, molybdenum disulfide molecules will fill the metal surface with microscopic pores, and make the metal surface more smooth, which makes molybdenum disulfide an ideal wear-resistant additive for nylon and metal friction occasions.

(2) Graphite.

The structure of graphite is the crystal structure of mineral graphite, hexagonal layer, this unique chemical structure makes graphite molecules easily slide each other when subjected to little friction, this wear resistance is particularly important in the environment with water, so graphite as an ideal wear-resistant additive used in many parts placed in water, such as water shell, blade and seal.

(3) Glass fiber.

Glass fiber can form a strong mechanical bond between polymers, so glass fiber can improve the integrity of thermoplastic structures and improve wear resistance. Glass fiber provides reinforcement and can improve the thermal conductivity and thermal deformation of plastics, significantly improving the load resistance and wear resistance of plastics.

(4) carbon fiber.

Similar to the case of glass fiber, carbon fiber can greatly improve the integrity of the material structure, load resistance and wear resistance. Unlike glass fiber, carbon fiber is a softer and less scratchy fiber, and carbon fiber will not scratch the friction surface of iron or steel against which it is rubbed.

(5) Aromatic polyamide fiber.

Aromatic polyamide fiber is also one of the wear resistant additives, unlike glass fiber and carbon fiber, it is the softest and most scratch free fiber, this property is the main advantage of aromatic polyamide fiber in wear resistant applications.

3

Add suitable wear-resisting additives

(1) Polytetrafluoroethylene (PTFE).

Polytetrafluoroethylene (PTFE) has a very low coefficient of friction, and PTFE molecules form a lubricating film on the surface of the part during friction. PTFE has good lubricity and wear resistance under friction, and is the best wear resistant additive in high load applications. These high-load applications include hydraulic piston ring seals and thrust washers. The PTFE content in amorphous plastics is generally 15%, and in crystalline plastics is generally 20%.

(2) polysiloxane.

Polysiloxane liquid is a migratory wear-resistant additive that, when added to thermoplastics, slowly migrates to the surface of the part and forms a continuous film. If the viscosity of polysiloxane is too low, the more quickly it can migrate to the surface of the part to provide wear resistance, but the viscosity of polysiloxane can not be too low, otherwise it is easy to volatilize and will quickly disappear from the part.

(3) Smoothing agent.

Such as oleic acid amide, erucic acid amide and other smoothing agents, when they are added to the thermoplastic, will migrate to the surface of the part to produce a wax layer, reducing the coefficient of friction while also reducing the visibility of scratches, the disadvantage is that it can not completely improve the surface sticky phenomenon.