Abstract: A method to recycle spent ethylene glycol in a continuous process for the manufacture of polyethylene terephthalate in at least one reactor vessel which includes:a. condensing the overhead vapor of spent ethylene glycol, water and other byproducts from the reactor vessel,b. feeding the condensed vapor to a single distillation column,c. removing only part of the water and other byproducts from ethylene glycol by distillation overhead in the column andd. feeding the resultant bottoms of the column back to the reactor vessel as recycle ethylene glycol along with virgin ethylene glycol, so that polyethylene terephthalate polymer being manufactured by the continuous process is essentially unaffected regarding polymer color and ability to be spun into high quality yarn, but with lower diethylene glycol content that polymer made from all virgin ethylene glycol.

Abstract: High strength polyester multifilament yarn of improved dimensional stability, which has the proper combination of an intrinsic viscosity of at least 0.90, relatively low work loss and a high degree of toughness, is incorporated as tire cord into a rubber tire for reinforcement to provide an important improvement in fatigue life and retained fatigue strength. The continuous melt-spin process comprises the steps of feeding prepolymer to a first finisher vessel to achieve at least 0.4 intrinsic viscosity transferring polymer to a second finisher vessel for a period sufficient to achieve an intrinsic viscosity of at least 0.95, and supplying this polymer to an extrusion spinnerette.

Abstract: High strength polyester multifilament yarn of improved dimensional stability, which has the proper combination of an intrinsic viscosity of at least 0.90, relatively low work loss and a high degree of toughness, is incorporated as tire cord into a rubber tire for reinforcement to provide an important improvement in fatigue life and retained fatigue strength. The continuous melt-spin process comprises the steps of feeding prepolymer to a first finisher vessel to achieve at least 0.4 intrinsic viscosity transferring polymer to a second finisher vessel for a period sufficient to achieve an intrinsic viscosity of at least 0.95, and supplying this polymer to an extrusion spinnerette.

Abstract: High strength polyester multifilament yarn of improved dimensional stability, which has the proper combination of an intrinsic viscosity of at least 0.90, relatively low work loss and a high degree of toughness, is incorporated as tire cord into a rubber tire for reinforcement to provide an important improvement in fatigue life and retained fatigue strength. The continuous melt-spin process comprises the steps of feeding prepolymer to a first finisher vessel to achieve at least 0.4 intrinsic viscosity transferring polymer to a second finisher vessel for a period sufficient to achieve an intrinsic viscosity of at least 0.95, and supplying this polymer to an extrusion spinnerette.

Abstract: In a reactor, for the continuous polymerization of feed materials to higher viscosity process fluid, comprising a vertical, hollow vessel having an inlet for the introduction of feed materials, an outlet for the discharge of process product and an exhaust for reaction vapors; and means for heating the vessel; the improvement comprising a draft tube, partially immersed vertically in the process fluid, the non-immersed end of the tube having at least one annular plate on the periphery thereof which overhangs the process fluid; and an impeller, located within the draft tube and propelling the process fluid up the draft tube and over the plate.

Abstract: This invention is an improved process to remove volatiles from molten synthetic, preferably fiber forming relatively high viscosity polymers which comprises passing molten polymer through a rotary disk polymer processor at a temperature of between 260.degree. C. and 300.degree. C. at a rate of between about 10 and 75 pounds (4.5 and 34 kg) per hour per square foot (0.093 m.sup.2) of processor filming area, at a rotational rate of between about 5 and 75 rpm for the disks, and a processor having between 1 and 20 stages.