| 摘要 |
Structural members for doors and the like can be manufactured from plastic foamed composites containing wood flour by the steps of (1) dry mixing a blend of powders including PVC powder, wood flour, powdered thermal stabilizers, powdered foaming agent and a powdered gelatinization agent, (2) adding the mixed powder to a thermal stirring mixer to obtain a homogeneous dispersion of the several powders (3) transferring the homogeneous dispersion of powders to a cold stirring mixer and stirring at speeds sufficient to avoid agglomeration of the homogeneous dispersion of the several powders and (4) placing the non-agglomerated homogeneous dispersion of the several powders in a feeding hopper of an extrusion machine and extruding shapes for the desired components. The vacuum venting of the extrusion machine can be controlled to achieve components with more desirable surface features. Lubricants can be added to the homogeneous dispersions of the several powders to aid in the extrusion process. |
