The effect of polypyrrole coatings on the adhesion and structure properties of UHMWPE fiber

To improve the adhesion between ultrahigh molecular weight polyethylene (UHMWPE) fiber and polymer matrix, pyrrole is oxidatively polymerized on the UHMWPE fiber surface continuously. The micro-composite of polypyrrole (PPy)-coated fiber/epoxy was prepared and the fiber was studied by interfacial shear strength (IFSS) through a single fiber pull-out method. Compared with the UHMWPE fiber as-received, the mean value of IFSS between PPy-coated UHMWPE and epoxy increased from 1.06 MPa to 5.72 MPa. In addition, the surface morphology and structure of PPy-coated UHMWPE fiber were studied by SEM, FT-IR, DSC and DMA. The results showed that PPy-coated UHMWPE fiber surface was observed with some particles attached. Although there is no chemical interaction between PPy and UHMWPE chains, PPy has some interaction with UHMWPE molecular chains according to the results of DMA. The PPy coatings have an effect on the adhesion may be associated with the roughened surface of the fiber and upon intermolecular interaction.