Why WPC granulation process is necessary for WPC decking production?
The traditional one-step WPC decking production process which directly melts and extrudes wood powder and plastic, resulting in the wood-plastic board cracking and fading within half a year, and the compressive strength is also very poor. Therefore, the wood-plastic granulation process is necessary to solve the three fatal problems:
① The challenge of poor wood-plastic integration: Since wood is hydrophilic and plastic hydrophobic, direct extrusion molding of mixed materials often results in delamination and insufficient nail-holding strength. The wood-plastic particle process employs coupling agents that bind to both ends – capturing the hydroxyl groups of wood powder and the carbon chains of plastic. This innovative chemical bonding technique enables seamless integration of these incompatible materials, boosting tensile strength by 300% in wood-plastic composites.
② The carbonization issue of wood powder under high temperatures: While wood powder carbonizes at temperatures above 200℃, plastic requires approximately 200℃ for plasticization. The one-step molding process compromises this critical balance, resulting in compromised product performance. Through the wood-plastic granulation process, raw materials achieve plasticized melting under high-temperature and high-pressure conditions without compromising properties. During granulation, wood powder and plastic undergo thorough contact, forming a network structure that enhances product creep resistance by 500%.
③ Appearance issues of wood-plastic composites (WPC): Direct one-step extrusion produces WPC products with uneven coloration that fades significantly within a year, making them unsuitable for high-end applications. However, through the wood pelletization process, engineers can incorporate market-specific additives like antioxidants and UV stabilizers. This approach substantially enhances product quality and durability while meeting specific market demands.
