||Glycol Producers and Users Sought for Interlab Study
ASTM Committee E15 on Industrial and Specialty Chemicals is seeking glycol producers
and users to participate in an interlaboratory study to determine
the precision and bias for ASTM E 2193, Standard Test Method for Ultraviolet Transmittance of Monoethylene
Glycol (Ultraviolet Spectrophotometric Method). To participate,
contact Passwater at 281/544- 6740.
A standardization consultant and two chemists working with stakeholders
in ASTM Subcommittee E15.02 on Product Standards based new ASTM
E 2193 on an original Shell Chemical method that determines the
transmittance of monoethylene glycol (1,2-ethanediol; MEG) at
wavelengths in the region 220 to 350 nm, says Deborah K. Passwater,
chemist, EO/Glycols, Shell Chemical LP, Houston, Texas. The original
method had been used internally at Shell for many years, Passwater
says. When industry members wanted a uniform industry method for
ultraviolet transmittance of monoethylene glycol, they presented
the Shell method to ASTM to be developed through voluntary consensus.
The Society reviewed the Shell method, and approved it as new
ASTM Standard E 2193 on March 10.
Most polyester fiber grade MEG producers and users have specifications
that require a minimum UV transmittance value, explains Passwater.
The methods currently used in the industry are inconsistent across
both producers and users. The ASTM E 2193-02 standard UV method
will provide a consistent industrial method that can be utilized
and referenced by all.
Monoethylene glycol is an extensively used industrial feed stock
for polyester production, including polyethylene terephthalate
(PET) plastics, continues Passwater. UV measures the presence
of compounds in MEG that absorb light in the ultraviolet region
of the spectrum. These undesirable compounds are in trace quantities
in the ppb ranges and primarily unknown in chemical structure.
Thus, they cannot be measured directly. UV is measured extensively
during the glycol production process, product release and product
Ultraviolet transmittance is one of the most important quality
parameters that have impact on the polyester product quality,
she concludes. Glycol that has poor or low UV transmittance can
negatively impact the appearance of the final product.
To participate in the interlab study, contact Deborah K. Passwater, Shell Chemical LP, Houston, Texas (phone: 281/544-6740). Committee
E15 meets Oct 7-8 in Jackson Hole, Wyo. For meeting or membership
details, contact Diane Rehiel, manager, ASTM Technical Committee Operations (phone: 610/ 832-9717).
Copyright 2002, ASTM