Preparation of Polyrotaxane Fibers. Part II: Tensile Properties of Polyrotaxane Fibers Treated with Two Cross-linking Reagents

Polyrotaxane fibers prepared with wet spinning of polyrotaxane consisting of poly(ethylene glycol) and cyclodextrins were cross-linked with two different cross-linking reagents, i.e., divinyl sulfone (DVS) and ethylene glycol diglycidyl ether (EGDE), to improve the tensile properties of the fibers. By cross-linking with DVS, the values for the tenacity at break and the initial modulus were increased with cross-linking time, while the elongation at break was improved only moderately. On the other hand, drastic improvements in elongation at break were observed after EGDE cross-linking, up to 645% of its original length, although the tenacity at break and the initial modulus showed only slight improvements. After cross-linking, only minor changes in the degree of crystallinity of the fibers were observed by wide-angle X-ray scattering measurements.