Swelling Interaction, Plasticization, and Antioxidant Extraction between Fiber Optic Cable Gels and Polyolefins

The effects of various waterblocking gels are investigated in relation to swelling behavior of polyolefins. Gel absorption is studied in polyethylene and polypropylene/ethylene copolymers as a function of temperature for a density range of 0.868 g/cc to 0.948 g/cc for polyethylene and 0.88 to 0.91 g/cc for propylene/ethylene copolymers. The effect of swelling on antioxidant extraction is also studied as a function of antioxidant molecular weight and degree of swelling. Both factors show a strong influence on the amount of antioxidant extracted. A direct correlation is found between antioxidant extraction by gels and reduction in thermo-oxidative stability.