| 摘要 |
The process according to the invention aims at partly solving the difficult radiation sterilization problem of polypropylene non-woven fabrics resulting from the low resistance to gamma-radiation of the draw-oriented fibre polymer. According to the invention, the gamma-radiation induced damages to the physical properties of polypropylene can, in addition to the choice of polymer and use of stabilizing additives, be reduced by regulating, in the fibre production, the super- and microstructures of the polymer matrix and by preventing detrimental structural changes of the polymer during the production and post-treatment processes of the fibre and non-woven fabric. When carrying out the process, the melt spinning and drawing processes in the fibre production are regulated so that the product fibre to its superstructure is in the area of deformed spherulites, to its microstructure in the monoclinic-amorphous structural system, to its crystallinity higher than about 15 mass-% and to its average chain orientation above the value of about 0.6 (60%). According to the process, care should be taken so as not to exceed an actual polymer matrix temperature of about 120 DEG C in the fibre and non-woven fabric production processing stages following the melt spinning, especially at average chain orientation values of the fibre structure of between 0.60 (60%) and 0.76 (76%). |
