Method and apparatus for increasing an intrinsic viscosity of polyester
First Claim
1. Apparatus for increasing the intrinsic viscosity of polyester by solid state polymerization comprisinga supply of heated polyester material including an extruder for producing strands of the material,a polyester granulator having a chamber housing a cutter for cutting the polyester material strands received from the extruder into granules while subjecting the strands to a coolant to only surface-cool the strands to a strand temperature slightly below the melting temperature of the polyester,a screening device directly bordering the chamber for separating the granules from the coolant so as to maintain the granules at a temperature only slightly below the melting temperature of the polyester by receiving polyester granules and coolant directly from the chamber,a solid state polymerization-thermal treatment unit including a polymerization-thermal treatment container, anda screw conveyor receiving granules at a temperature only slightly below the melting temperature of the polyester directly from the screening device for transporting the granules from the screening device directly into an interior of the container to thereby utilize residual heat in the granules received from the conveyor during a polymerization process of the granules conducted in the interior of the container.
0 Assignments
0 Petitions
Accused Products
Abstract
A method of increasing the intrinsic viscosity of polyester by means of solid state polymerization, wherein a polyester plastics melt is granulated and after granulation is conveyed into a thermal treatment container (13) for thermal treatment therein, the granules being produced slightly below their melting temperature and being fed into the thermal treatment container (13) immediately after granulation so as to utilize the residual heat in the granules, as well as an arrangement for increasing the intrinsic viscosity of polyester by means of solid state polymerization with a granulating and a thermal treatment unit, with an unheated, thermally insulated container (13) or a container (13) having wall heating means (15) being provided as the thermal treatment unit, which is directly connected to the granulating unit via a conveying device (11, 36, 37).
47 Citations
15 Claims
-
1. Apparatus for increasing the intrinsic viscosity of polyester by solid state polymerization comprising
a supply of heated polyester material including an extruder for producing strands of the material, a polyester granulator having a chamber housing a cutter for cutting the polyester material strands received from the extruder into granules while subjecting the strands to a coolant to only surface-cool the strands to a strand temperature slightly below the melting temperature of the polyester, a screening device directly bordering the chamber for separating the granules from the coolant so as to maintain the granules at a temperature only slightly below the melting temperature of the polyester by receiving polyester granules and coolant directly from the chamber, a solid state polymerization-thermal treatment unit including a polymerization-thermal treatment container, and a screw conveyor receiving granules at a temperature only slightly below the melting temperature of the polyester directly from the screening device for transporting the granules from the screening device directly into an interior of the container to thereby utilize residual heat in the granules received from the conveyor during a polymerization process of the granules conducted in the interior of the container.
Specification