Influence of fiber surface treatment on the creep behavior of jute fiber-reinforced polypropylene

Improvements in the characteristic properties of jute-polypropylene composi tes were obtained with the application of MAH grafted PP copolymers as a co upling agent to the fiber. SEM investigations demonstrated that fiber pull- out is reduced after the modification with the coupling agent. This improve d fiber-matrix adhesion further leads to a lower creep strain in the outer fibers. This was demonstrated for composites with two different fiber conte nts. Up to applied stresses of 5.1 N/mm(2), the creep behavior for the comp osites with unmodified, as well as for those with MAH-PP modified, fibers o beys the creep law according to Abbott. The experimental data of creep test s at higher applied stresses were fitted more successfully by using the cre ep law according to Findley. The creep kinetic coefficient according to Abb ott was dependent on the applied stress for both types of composites and fo r both fiber contents.