DAK Americas ArrayEBM User Manual

PDS-B95A Rev 04/10

DAK Americas

ISO 9001:2008

#10004457

Property

Value

Unit

Test Method

Intrinsic Viscosity

1.10 +- 0.03

dL/g

DAK-QAR-SOP-0012

Color L*

81 +- 4

Hunter

LP-100

Color b*

-0.5+- 2.5

Hunter

LP-100

Acetaldehyde

2 max

ppm

DAK-QAR-SOP-0010

Moisture Content (as packaged)

0.25 max

Weight %

DAK-QAR-SOP-0013

Fines (as packaged, +24 Mesh Size)

0.10 max

Weight %

DAK-QAR-SOP-0014

Chip Size

49 to 59

Chips/g

DAK-QAR-SOP-0015

Melt Point

235 to 245

°C

DAK-QAR-SOP-0016

Array® EBM Product Information

polyethylene terephthalate resin

Product Description

Array® EBM polyethylene terepthalate (PET) resin is designed to have the melt strength and slow
crystallization rate required to produce large handle ware containers by extrusion blow molding. It
performs exceptionally well in the manufacture of thick walled containers where maintaining clarity and
neutral color are important. The higher intrinsic viscosity of this product gives the melt strength required
to maintain parison shape in continuous extrusion.

This product can be used with up to 50% in-plant regrind provided that the regrind has been dried.
In addition, DAK has designed Array® EBM to be recyclable with other PET products and this product

has met the APR Critical Guidance Document guidelines for PET

Food Contact

Array® EBM is ideally suited for food packaging applications and may be used in contact with food as
described on Food Contact Notification (FCN) 635 in full compliance with the Federal Food, Drug and
Cosmetic Act.

Sales Specifications (5860)

*This a development product. The specifications have not been finalized and are subject to change.
This product is spherical PET resin pellets made by the DAK Americas Melt-Tek® process.
These values represent the anticipated performance data for these polyester resins and intermediates; they are not intended to

be used as design data. We believe this information is the best currently available on the subject. It is offered as a possible
helpful suggestion in the experimentation you may care to undertake along these lines. It is subject to revision as additional
knowledge and experience is gained. DAK Resins makes no guarantee of results and assumes no obligation or liability
whatsoever in connection with this information. This publication is not a license to operate under, or intended to suggest
infringement of, any existing patents.

CAUTION: Do not use in medical applications involving permanent implantation in the human body. For other medical

applications, see “DAK Medical Caution Statement”.

DAK Americas LLC

Gateway Corporate Center, Suite 210

223 Wilmington W Chester Pike• Chadds Ford, PA 19317

1-888-738-2002 • fax: [phone] • www.dakamericas.com

PDS-B95A Rev 04/10

DAK Americas

ISO 9001:2008

#10004457

Array® EBM Product Information

polyethylene terephthalate resin

Material Drying
Proper drying of polyethylene terephthalate (PET) is essential to produce a high quality part (container,
film, etc.) with optimum physical properties. PET is hygroscopic, meaning that when it is exposed to
humid atmospheres, it will absorb moisture. In PET the moisture is not only on the surface but diffuses
slowly through the whole pellet and is firmly held by molecular attraction. Before processing the PET,
this moisture must be removed. Carefully controlled drying of all PET is an essential requirement for
optimum processing performance and final product properties. If drying is not carried out properly, to
the known requirements of the type of PET in use, then deficiencies in process and product will results.
The deficiencies will be impossible to remedy by later process changes. These defects arise in the
injection molding or extrusion processes because at PET melt temperature (250°-280° C) any water
present causes hydrolytic degradation of the PET, almost instantaneously, with the resultant loss in
intrinsic viscosity (IV). Significant drops in IV cause loss of process control and reductions in end
product properties.

Drying of PET polymer involves the diffusion of absorbed moisture from the interior of the polymer chip
to its surroundings and, subsequently the removal of moisture from the bulk of polymer chips. The final
moisture of the PET polymer should be less than 30ppm and preferably 10 to 20ppm.Moisture removal
can be achieved by heating the polymer chip under dry air or vacuum. In an air drying system, heated
dehumidified air flows up through a chip bed and returns to the dehumidifier. The key requirements for
a reliable drying process are:

Drying temperature: The ACTUAL chip temperature should achieve between 300° and 340° F
measured at the dryer exit.

Dehumidified air temperature: Correctly designed equipment should operate at temperatures up to
340° F measured on entry to the dryer hopper, with an absolute maximum of 370° F to prevent possible
discoloration.

Dehumidified air dew point: This should not be allowed to rise above –34° F and should preferably be
–40° F or lower, measure after the desiccant bed. Always check the correct regeneration temperatures

are being used.
Dehumidified air flow through the chip bed: Most dryers operate at around l cfm of airflow per 1lb/hr of

PET chip as a minimum requirement, with the airflow at the correct temperature and dew point.
Chip residence time (drying time): DAK recommends a chip residence time for Array® EBM PET of not

less than five hours and preferably six hours. This is the theoretical drying time, which is calculated by
dividing dryer capacity in lbs. by throughput in lb./hr. Extended periods of high temperature can
adversely affect the polymer processing conditions. In the event of a stoppage for an extended period,

DAK Americas LLC

Gateway Corporate Center, Suite 210

223 Wilmington W Chester Pike• Chadds Ford, PA 19317

1-888-738-2002 • fax: [phone] • www.dakamericas.com