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PVC-ASA Double Co-extrusion WPC Decking

Source：Plastic wood flooring - Plastic wood guardrail - Plastic wood materials - Official website of Dongguan Baituomu New Materials Technology Co., LTD Published:2019-06-26

ASA-PVC co-extruded wood is extruded from two extruders, PVC plastic wood substrate and ASA co-extruded coating material, and then through the co-extrusion compound die, the ASA coating layer adheres when extruded with the substrate. On the surface of the substrate to achieve the purpose of coating the substrate. Co-extrusion coating properties are also different due to the different materials used in the coating. Currently, the co-extruded coating materials mainly include PMMA, PVC and ASA.

ASA/PVC plastic wood co-extrusion production process

1. Processing of raw materials:

PVC plastic wood is made of PVC resin, wood powder, stabilizer, lubricant, filler, modifier, etc., which is the same as the general PVC mixing process. The ASA material should be dried before processing to prevent defects such as pitting and notting on the surface. The drying conditions are: 85 ° C - 95 ° C, 3-6 hours.

Process conditions

Matters to be noted in the production of raw materials: ASA materials must be dried, the first drying time should be slightly longer, not less than 4 hours. The drying temperature should be selected according to the specific conditions. The temperature is high and the time can be shorter. When the temperature is low, the time can be extended, but the maximum time cannot exceed 24 hours.

2. Treatment of surface scratches:

After the product is demolded, the surface of the ASA has no scratches, which is very smooth and uniform. After cooling and setting, the surface will have powdery substances; after cooling, the surface will have obvious scratches. In this regard, it must be ensured that the sizing mold is smoother, there is no right angle transition joint, and the scratches are less; the shorter the sizing mold, the less the surface scratches, the product produced by the two-stage sizing mold is more scratched than the product produced by the four-stage sizing mold. To be less; the last three segments of the 4-stage sizing die are properly treated, and the products produced are almost scratch-free, and the surface condition is greatly improved.

3. Control of the thickness of the co-extruded layer:

The thickness of the ASA coextruded layer is related to the weatherability, hiding rate, and processability of the ASA coating, and the thickness of the coextruded layer is controlled by controlling the amount of extrusion of the coextrusion machine. ASA is extremely weather resistant and has good compatibility with PVC. The combination is very strong. Therefore, the general ASA co-extruded layer thickness of 0.2-0.3mm can meet the quality requirements. The thickness is too thin, some of the lighter colors will appear white; the thickness is too thick, the profile will sometimes bend, so controlling the thickness of the co-extruded layer is very important to ensure product quality.

With the global depletion of forest resources and the increasing awareness of national environmental protection, the wood-plastic industry has developed well, and ASA-PVC co-extruded wood has also been widely used in gardens, transportation, construction, home improvement, car and boat interiors. .