Re-use of thermoplastic scrap - by reprocessing mixtures of different resin mouldings into thick walled components with fibrous texture
Реферат: Recovered pieces of film, foam, sheet, mouldings etc. comprising principally polyolefins, polystyrenes or vinyl resins are if necessary firstly isolated from other materials by conventional sorting, washing and milling techniques. The resulting dried ground mixture of recovered resins is analysed and then enriched if necessary with selected resins to create a roughly standard compsn. This adjusted feedstock is then dried with a blowing agent and reprocessed using temps. higher than those required by any of the component resins in the pure state, usually at 150-180 degrees C, to obtain an extrudate or (injection) moulding with a fibrous cellular structure, with a surface which normally consists preferentially of PVC with a highly glazed surface. The mixture may contain some particles of other materials such as polyamides or comminuted papers which are infusible at the reprocessing temp. used and which act as filler grains within the body of the product component. Method is used in mfr. of relatively thick walled components such as synthetic planking, being receptive to screws, nails, or similar fastenings, self extinguishing w.r.t. flammability, dimensionally stable and rot-proof.
Method for sorting plastics from a particle mixture composed of different plastics
Номер патента: US5566832A. Автор: Bjorn Stuckrad,Karsten Lohr. Владелец: Daimler Benz AG. Дата публикации: 1996-10-22.