Fatigue Properties of Highly Oriented Polypropylene Tapes and All-Polypropylene Composites

摘要

This paper describes the fatigue behaviour of newly developed all-polypropylene (all-PP) tapes and composites,with reference to the composite processing conditions,testing temperature and making a comparison with commercial alternatives.All-PP tapes are highly oriented and their failure behaviour follows that of other highly oriented polymers.All-PP woven composites fail ultimately due to PP tape failure.However,this failure mode is accompanied by delamination of fabrics in the woven structure.Consolidation pressure plays a decisive role in controlling the interlaminar properties and hence the delamination resistance and furthermore the fatigue limit of the composite.Comparison of all-PP woven composites with commercial alternatives based on glass and natural fibres reveals the excellent relative performance of all-PP composites under fatigue loads.Fatigue properties of all-PP composites are however sensitive to the testing temperature,and elevated temperatures can lead to a rapid reduction of the fatigue resistance of these all-polymer systems.