The present invention relates to a process for continuous production of partly crystalline polycondensate pellet material, comprising the steps of forming a polycondensate melt into pellet material; separating the liquid cooling medium from the pellet material in a first treatment space, wherein the pellets after exit from the first treatment space exhibit a temperature T.sub.GR, and crystallizing the pellet material in a second treatment space, wherein in the second treatment space fluidized bed conditions exist, and in the second treatment space the pellets are heated by supply of energy from the exterior by means of a process gas.

The present invention relates to a process for continuous production of partly crystalline polycondensate pellet material, comprising the steps of forming a polycondensate melt into pellet material; separating the liquid cooling medium from the pellet material in a first treatment space, wherein the pellets after exit from the first treatment space exhibit a temperature T.sub.GR, and crystallizing the pellet material in a second treatment space, wherein in the second treatment space fluidized bed conditions exist, and in the second treatment space the pellets are heated by supply of energy from the exterior by means of a process gas.

A process and a system for producing polyethylene terephthalate (PET) granules by transesterification of dimethyl terephthalate with ethylene glycol or by esterification of (fiber) purified terephthalic acid with ethylene glycol suitable for further processing to form packaging films and bottles, comprising the steps of polycondensation, granulation and latent heat crystallization, aftertreatment of the crude granules to adjust the polymer quality values required for the further processing, in particular the intrinsic viscosity, the acetaldehyde content and the moisture content, wherein the aftertreatment is carried out in multiple moving bed tubular reactors operated in parallel.

The present disclosure relates to a polyester resin blend. The polyester resin blend can provide a thick container with high transparency even if it contains recycled polyethylene terephthalate as well as virgin polyethylene terephthalate. In addition, the resin blend can be reused by itself, and is expected to be useful for providing continuously usable plastics that have been recently attracting attention.

A process can prepare a bio-resorbable polyester as a granulate or powder by bulk polymerization of one or more monomer(s). The process involves a) filling a monomer granulate, containing the one or more monomer(s), into a container; b) adding a polymerization catalyst and a chain length moderator on top of the monomer granulate; c) adding further monomer granulate on top; d) closing the container; e) carrying out a polymerization reaction in the closed container at a temperature in the range of 50° C. to 170° C., wherein a solid polymer in the form of a polymer block is formed; f) removing the polymer block from the container; and g) comminuting the polymer block to a granulate or powder; wherein the container is an unstirred container, wherein steps b) and c) are carried out once or are repeated, and wherein steps a) to e) are carried out under inert atmosphere.

A process can prepare a bio-resorbable polyester as a granulate or powder by bulk polymerization of one or more monomer(s). The process involves a) filling a monomer granulate, containing the one or more monomer(s), into a container; b) adding a polymerization catalyst and a chain length moderator on top of the monomer granulate; c) adding further monomer granulate on top; d) closing the container; e) carrying out a polymerization reaction in the closed container at a temperature in the range of 50° C. to 170° C., wherein a solid polymer in the form of a polymer block is formed; f) removing the polymer block from the container; and g) comminuting the polymer block to a granulate or powder; wherein the container is an unstirred container, wherein steps b) and c) are carried out once or are repeated, and wherein steps a) to e) are carried out under inert atmosphere.

Aromatic polyester particles which are formed from an aromatic polyester having a flow starting temperature of 400° C. or higher and have a circularity of a projected image of 0.80 or more and 1.00 or less.

A method for producing a decolorized polyester according to the present invention includes: a step of preparing a polyester colored with a colorant, and a decolorizing agent containing a glycol ether-type compound having a boiling point at atmospheric pressure of 160° C. or higher; and a step of removing the colorant, by bringing the decolorizing agent into contact at least once with the colored polyester while heating the decolorizing agent to a temperature equal to or lower than a melting point of the polyester, to thereby obtain the decolorized polyester.

A build material for additive manufacturing applications is disclosed. The build material includes a build composition in powder form, The build composition includes a semi-crystalline polymer having a glass transition temperature of at least 70° C. and an onset melting temperature of at least 125° C., as measured by DSC, and that exhibits an amorphous return. A semi-crystalline polymer useful in additive manufacturing applications and a method for making the semi-crystalline polymer article are also described.

A build material for additive manufacturing applications is disclosed. The build material includes a build composition in powder form, The build composition includes a semi-crystalline polymer having a glass transition temperature of at least 70° C. and an onset melting temperature of at least 125° C., as measured by DSC, and that exhibits an amorphous return. A semi-crystalline polymer useful in additive manufacturing applications and a method for making the semi-crystalline polymer article are also described.