Formula and material of WPC production from plastic wastage

Material Name

Function and Notes

Formula quantity

PE/PP plastic (recycled flakes or granules)

 serving as the primary polymer matrix of the wood-plastic composite profile, functions to bind the wood powder and other fillers into a cohesive structure while imparting the necessary thermoplastic processability and toughness to the final product.

25-30%

Wood Powder

 which serves as the main bio-based reinforcing filler of the composite, can significantly reduce the production cost of the finished profile while improving the rigidity and dimensional stability of the product. It is generally derived from forestry processing residues or agricultural waste, which is in line with the direction of low-carbon circular utilization of resources.

50-70%

CaCo3

 which is commonly used as an inorganic filler in the formula, can further reduce material cost, improve the heat resistance and surface scratch resistance of the finished profile, and adjust the overall shrinkage rate of the product during extrusion molding.

0-10%

Coupling agent

which acts as a compatibilizer between the organic polymer matrix and inorganic fillers/biomass fillers, can effectively improve the interfacial binding force between two phases with different polarities, avoid the problem of uneven dispersion of fillers and reduce the mechanical properties of the product.

0.8-1.5%

PE wax

 It is a commonly used internal and external lubricant in extrusion processing, can effectively reduce the friction between the polymer melt and the processing equipment, improve the fluidity of the melt during extrusion, and help the formed profile to obtain a smoother surface. It will not significantly affect the mechanical properties of the product when added within a reasonable range

1.2-2.0%

Stearic Acid

It is a traditional low-cost lubricant in extrusion processing, can play a good role in promoting melt release in the extrusion system, cooperate with other lubricants such as PE wax to adjust the overall lubrication balance of the formula, and help improve the surface gloss of the extruded profile. It is widely used in various modified polyolefin extrusion formulas

1.5-2%

Pigment (optional)

It is mainly used to endow the final extruded product of WPC core layer with specific colors to meet different appearance needs.

 for customized color

Anti UV agent (optional)

It is an optional additive for WPC core layer formulations, which is mainly used to improve the weather resistance of the finished product. It can slow down the degradation and aging of polymer materials caused by ultraviolet radiation when the product is used in outdoor environments, and effectively prolong the service life of the WPC product. It is generally added when the product has long-term outdoor use requirements

Customized 0.1-0.3%

Anti oxygen agent (optional)

It is a functional additive that can effectively inhibit the oxidative degradation of polymer matrix during high temperature extrusion processing and long-term service, preventing the finished product from appearing problems such as brittleness, cracking and performance degradation caused by oxidation. It can cooperate with anti UV agent to jointly improve the aging resistance of WPC products, which is a common additive in outdoor wood-plastic formulas.

Customized 1-3%

Co-extrusion material (optional)

It is the necessary material for the WPC co-extrusion process, which usually made by core base material, pigments, and chemical additives. Compared with conventional WPC materials, co-extrusion materials can endow the product with a more scratch-resistant, stain-resistant and weather-resistant surface through integrated co-extrusion molding, which can further improve the overall service performance and service life of the product.

For co-extrusion outer durable layer, 0.5-1.2mm thickness