The Applied Technical Services Family of Companies (ATS FoC) conducts polymer viscosity testing in accordance with ASTM D4603 to support quality control and inform material selection.
What Does ASTM D4603 Measure?
ASTM D4603 is a standard for measuring the inherent viscosity of polyethylene terephthalate (PET) using a glass capillary viscometer.
This standard measures polymer viscosity to provide insight into material quality and chemical chain length. Unlike similar standards, ASTM D4603 specifies solvents specifically for PET polymers.
Why is Viscosity Critical to PET Quality Control?
Viscosity is essential for determining a polymer’s molecular weight and processability. Because PET is often used in applications requiring strength and thermal stability, monitoring inherent viscosity is important to overall material quality.
Measuring PET viscosity helps to:
- Monitor Batch Quality
- Inform Material Selection
- Improve End-Product Quality
- Examine Molecular Weight and Chain Length
- Meet Industry Standards
Which Industries Commonly Request ASTM D4603 Testing?
Industries that require high-performance PET materials frequently request ASTM D4603 testing, including:
- Polymer and Plastic Manufacturers
- Packaging Industries
- Textile Manufacturers
- PET Recycling Facilities
Polymer testing to applicable standards supports material quality and performance. Partnering with a reputable laboratory ensures reliable and accurate results.
Trusted Polymer Testing Backed by ATS Expertise
The ATS FoC is committed to creating a safe and reliable world. Since partnering with SGS in 2026, we have expanded our testing, inspection, calibration, and consulting (TICC) services to support clients worldwide.
In addition to ASTM D4603 testing, our polymer laboratories offer a range of environmental, mechanical, and chemical analyses. Our polymer testing services include:
- Accelerated Weathering
- Material Identification
- Failure Analysis
- FTIR Analysis
- Flexural Strength Testing
- VOC Testing
- BPA Testing
The ATS FoC maintains several ISO/IEC 17025:2017 accreditations in multiple disciplines, including chemical, calibration, electrical, non-destructive, and mechanical services. We operate under an ISO 9001:2015-registered quality management system.
Contact Us
Whether you require tensile testing or chemical analysis, our experts can help you meet your business needs. Contact the ATS FoC for your ASTM D4603 testing by submitting our web form or calling +1 (888) 287-5227.

