Highly crystalline polyester or copolyester in which the degree of crystallinity is controlled by latent heat crystallization, used especially for the production of food containers and drinks bottles

摘要

Polyester or copolyester (I) with a degree of crystallisation (DC) which is controlled by a latent heat crystallization process, shows a DC of at least 38%. An independent claim is also included for a method for the production of granules from a (co)polyester melt with high intrinsic viscosity (I.V.) made in a continuous or discontinuous melt-polycondensation reactor, in which the method includes a latent heat crystallization stage which gives granules with a DC of more than 38% and an acetaldehyde content of 0.5-100 (preferably 0.5-70, especially 0.5-60) ppm.