MORPHOLOGY AND MECHANICAL PROPERTIES OFCROSSLINKED PE/PE COMPOSITE MATERIALS

摘要

Novel peroxide-crosslinked composite materials based on ultra high molecular weightpolyethylene fibers were studied in comparison with their non-crosslinked homologues. Two materialtypes were prepared, either by embedding the fibers in a low-density polyethylene matrix, or bycompacting neat fibers. The resulting composites were analyzed by differential scanning calorimetry,focusing on the typical double-melting endotherm of the PE fibers, and by X-ray diffraction,concentrating on the characteristic weak 010 reflection of the triclinic phase in the fiber. Mechanicaltesting of unidirectional composites showed crosslinking to be highly advantageous, yieldingsignificant property enhancement, e.g., increasing the flexural modulus from 28 to 33 Gpa in thecompacted fiber composite. The advantage results from the crosslinking mechanism, entailing onlypartial melting that is confined to the fiber skin, while retaining a significant degree of crystallinity inthe fiber.