Solid high-IV polycondensation (S-HIP) technology for PET.
The main applications of high-viscosity PET are food-grade packaging and technical yarns. However S-HIP technology offers a very wide range of end product viscosities, which allows using the same plant not only for manufacturing bottle-grade polymer, but also products for food films and shells, tire cords, conveyor and safety belts, air bags, etc. The unique cleanness of PET produced by S-HIP technology makes it especially attractive for manufacturing bottles for mineral water.S-HIP is an evolutionary development of SSP technology in the manufacturing process of PET resin for use in packaging and bottles in particular. The process provides the best means of producing PET bottles with very low levels of AA. By granulating at an IV of 0.4 dl/g instead of the conventional 0.6 dl/g, the longer residence time in the solid state allows much lower levels of residual AA to be reached. More importantly the expensive melt finisher, where most degradation and side reactions leading to the formation of AA occur, can be eliminated.
