| 摘要 |
A process of forming an article of heat hardenable resin comprises blending the unset resin, a non-fibrous filler and a fibrous reinforcing ingredient into a mixture of workable consistency until the filler and reinforcing ingredient are wetted with the resin, feeding the material obtained to an extrusion chamber to compact the ingredients, then subjecting the material to a vacuum to release the gases and volatiles therefrom before feeding the material to a die and finally delivering the material in a form for hardening by final curing while self-sustaining the desired cross-section shape against substantial distortion. Specified resins are phenolformaldehyde resins, urea formaldehyde resins, polyester resins, poly-allyl phthalate resins, and epoxy resins especially those known as Paraplex P13, P43 and P47 ("Paraplex" being a Registered Trade Mark), styrene being added as a comonomer. The reinforcing agent may be glass fibre and the filler may be clay, calcium carbonate may also be added. Other materials which may be added are benzoyl peroxide compounded with calcium sulphate, camphor, hydrogenated terphenyls, stearic acid, tricresyl phosphate, p-chlorobenzoyl peroxide, 2:4 dichlorobenzoyl peroxide, dibutyl phthalate, and the dibenzylidene diperoxide. The mixtures may also be cured at room temperature by adding cobalt naphthenate or manganese naphthanate and spraying with a solution of styrene containing a peroxide. The extrusion device may be a ram type, or a single screw or a multiple screw extruder, and the final process may consist of injection moulding, compression moulding, transfer moulding or jet extrusion.
|
