PET with good transparency and its hollow molded products

The TiCl4 was added dropwise to ice-cooled water, ammonia was added at room temperature to adjust the pH to 9, and then an aqueous acetic acid solution was added to adjust the pH to 5. The precipitate was filtered, washed, and the precipitate was immersed in an aqueous EG solution having a mass fraction of 20%. After filtration, washing and drying, etc., a solid titanium compound (w (Ti) = 35.4%) was prepared, and 0.34 g of the titanium compound was dissolved in 100 g of EG to prepare a catalyst solution. Then, 13 kg of TPA and 4.93 kg of EG and 6.88 g of 20% Et4NOH in water were esterified at 260 °C for 6 h, and the generated water was simultaneously removed, and then stirred with 201 g of the catalyst solution. 1. Hg PO4 mixed with 85% mass fraction of 85%, heated under reduced pressure to 280 °C for 50 min, distilled out EG, cast strip out, cooled in water, cut into pellets (intrinsic viscosity 0. 54 dL / g, COOH value is 25 mol/t), dried at 170 °C, crystallized for 2 h, solid-phase polycondensed at 225 °C for 9 h, and the final prepared PET has an intrinsic viscosity of 0.78 dL/g, and the density is 1. 41 g/ cm3, the mass fraction of oligomer is 0.35%, the mass fraction of acetaldehyde is 1. 6 × 10 - 6, the mass fraction of Ti is 16 × 10 - 6, COOH value is 14 mol/ t, the crystallization temperature is 158 °C.

Reprinted from: Polyester Industry