Feasibility study on titanium‐catalyzed polyester for the preparation of high‐strength industrial yarns

Abstract

AbstractIn order to overcome the environmental pollution or personal injury caused by precipitation of heavy metal ions during post‐processing and application of antimony‐catalyzed polyester industrial yarns, the titanium catalyst was used to prepare polyethylene terephthalate (PET) with high molecular weight, and then the titanium‐ catalyzed PET properties related to spinning kinetics were investigated as a basis for designing the drying, melting, spinning and extrusion, cooling, hot stretching and heat‐ setting process parameters. Compared with the spinning process of antimony‐catalyzed polyester of similar molecular weight, based on the lower melting point and melt viscosity of titanium‐catalyzed PET, the spinning temperature was lowered by about 5°C to reduce the thermal degradation of PET during extrusion, and the hot stretching speed and temperature were appropriately lowered based on the characteristics of low crystallization temperature and high crystallization rate in the heating process so that a product with a breaking strength of 8.29 cN/dtex was developed on an industrial device successfully. Titanium‐catalyzed high‐strength polyester industrial yarns, the structure and properties of crystal orientation, lamellar thickness, strength and elongation at break were comparable with those of antimony‐catalyzed polyester industrial yarns.