摘要 |
PURPOSE: Chemical treatments for fibers and wire coated composite strands for molding fiber reinforced thermoplastic composite articles are provided to size and/or preimpregnate the fibers in use of a chemical treatment to fibers (10), such as reinforcing fibers (12) suitable for making a composite article. CONSTITUTION: A chemical treatment has a relatively low viscosity and is substantially solvent free and non radiation curable. Heat energy may be employed to lower the viscosity and improve the wetting ability of the applied treatment and/or to increase the molecular weight of, or otherwise cure, the treatment with essentially no generation of solvent vapor. The treated fibers (32) are used to form a composite strand (14), which may be subsequently processed in-line or off-line into a composite article having fibers disposed in a polymeric matrix. Another general aspect relates to encased composite strands, in thread or pellet form, and to wire coating methods and apparatus for making them. The strands are moldable into fiber reinforced thermoplastic composite articles. Each strand is made from fibers, including reinforcing fibers and optionally fibers of a matrix material, that are impregnated with a chemical treatment so that the treatment is disposed between substantially all of the fibers. |