Verbesserte elektromagnetische Abschirmung von Polymerwerkstoffen durch das synergistische Zusammenwirken von elektrisch leitfaehigen faserfoermigen Zusaetzen und ferroelektrischen Komponenten Abschlussbericht

The objective of this research project is the incorporation of ferroelectrics in plastics containing carbon fibres or steel fibres and into compounds containing metallized synthetic fibres in order to generate permeable conductance paths and polarizable micro domains in plastic materials. The authors work commercial steel fibre compounds and powder of ferroelectric barium strontium titanate into polypropylene (PP) and acrylonitrile-butadiene-styrene (ABS). These emi-finished products have a volume resistence of 0.1 to 10 #OMEGA#cm at a content of 10 mass.% of steel fibres. The shield attenuation of the composite containing barium strontium titanate is increased in comparison to the unfilled PP-SF- or ABS-SF reference probe (SF = steel fibre). The mechanical stability of the PP-SF composite is not influenced by the existence of 10 or 30 mass.% of ceramic components. With increasing the content of ceramic compound above 30 %, the impact strength diminishes. The impact strength of the ABS-SF-composites diminish above a content of 10 mass.% ceramic compound while the tensile strength and the flexural strength diminish above a ceramic content of 30 mass.%. According to the stability of the mechanical property niveaus, partly crystalline polypropylene is more suitable as the amorphous ABS matrix with respect to the incorporation of brittle and tenacity minimizing ceramic components. The enormous high ductility of the acrylic fibres in the polypropylene matrix leads to a high stable niveau of material tenacity at the ceramic containing PP-acrylic vleece-compounds. From economical point of view, the ceramic containing and steel fibre containing polymeric materials can be used in electromagnetically screening housings. The costs of composites with 10 % steel fibres and 10 % of a ferroelectric ceramic are nearly the same as the costs of ceramic free polymer-steel fibre system. But, the screening can be improved essentially.SIGLEAvailable from TIB Hannover: F04B52 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman