| 摘要 |
A linear material, esp. a monofilament, for fabricating sliding clasp fasteners, is prepd. from a polymer blend of 100 pts. wt. polyester and 1-10 (2-5) pts. wt. polypropylene. Pref. the polyester component is chosen from polyethylene terephthalate, polybutylene terephthalate or polycarbonate and has an intrinsic viscosity of 0.60-1.00. Pref. an extruded monofilament of the blend is drawn in hot water at 70-98 deg C. to a length of 3.0-4.5 times its original length, followed by a thermal treatment in the relaxed state at 200-270 deg C. and is subsequently drawn again under dry heat at 150-240 deg C. to a length of 1.2-1.8 times the length of the drawn filament. The filament pref. exhibits a variation in dia. of +/- 15/1000 mm. |
