Dak Americas LLC

Norman W Lisson

George F Rollend

Helen Jane Codd

Helen J Codd

A method for producing ultra-high intrinsic viscosity (IV) polyester resin pellets from a resin that contains one or more comonomers in an amount of up to 30 mol%. The method includes extruding a polyethylene terephthalate polyester starting material having a starting IV (IVst) meeting the following relationship: 0.65 dL/g &#x3c;IVst &#x3c;0.9 dL/g, to form resin particles having no more than 0.05 dL/g of IV lift due to solid-state polymerization, then latent heat crystallizing the resin particles to form crystallized particles having a variation of IV of no more than 0.05 dL/g across any dimension of the crystallized particles. The crystallized particles are then solid state polymerized to a final IV (IVf) of at least 0.9 dL/g to form the ultra-high intrinsic viscosity (IV) polyester resin pellets. During the solid state polymerizing the IV lift rate is at least 0.012 dL/g/hr.

Ultra-high IV polyester for extrusion blow molding and method for its production

An ultra-high IV polyester suitable for high melt strength end-uses, such as injection blow molding, pipe extrusion, profile extrusion, and extrusion blow molding, is provided, having IV of greater than 0.9; and a process for its production having high IV lift rate during SSP processing.

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Mount Pleasant, SC, United States of America

Norman W Lisson