Differential Scanning Calorimetry

Applications: Pipe factory outgoing inspection, scientific research, production R&D, teaching and training, 

third-party testing centers

FAQ– Differential Scanning Calorimeter (DSC)

Q: What is a differential scanning calorimeter (DSC) used for?

A: A DSC measures the heat flow difference between a sample and a reference material as a

function of temperature. It detects thermal events such as glass transition (Tg), melting, 

crystallization, curing, and oxidation — making it essential for material identification, quality

control, and R&D of polymers and plastics.

Q: What standards apply to DSC testing for plastics?

A: ISO 11357 is the primary standard series for DSC testing of plastics, covering general principles

(Part 1), glass transition temperature (Part 2), melting and crystallization temperature (Part 3), and

oxidation induction time (Part 6). ASTM E967 and E968 cover DSC temperature and enthalpy calibration.

For pipe materials, ISO 11357-6 (OIT) is particularly relevant.

Q: What is OIT and why is it important for pipe materials?

A: OIT (Oxidation Induction Time) measures how long a material resists oxidative degradation at a 

specified temperature. For PE and PP pipes used in hot water and gas distribution, OIT is a mandatory

quality indicator — it directly reflects the material's long-term stability and antioxidant effectiveness. 

A minimum OIT value is typically required by product standards such as ISO 15876 and ISO 22391.

Q: What sample forms can be tested with DSC?

A: DSC can test solids, films, powders. For plastics, samples are typically cut into thin slices (3–10 mg) 

from pellets, pipe wall sections, or sheet material. The sample should have good thermal contact with

the pan bottom — flat pieces or finely cut fragments work best.

Q: What temperature range do I need for plastic testing?

A: Most thermoplastic testing falls within -50°C to 350°C. For PE and PP, a range of -50°C to 300°C covers Tg,

melting, and OIT. For high-temperature engineering plastics like PEEK or PPS, you may need up to 450°C. 

If you test pipe materials with OIT requirements, ensure your DSC supports isothermal holds at 200–220°C.

Q: How much sample is needed per test?

A: Typically 3–10 mg. Smaller samples heat more uniformly and give sharper peaks, but too little sample

reduces signal strength. For OIT testing of pipe materials, 5–10 mg is standard per ISO 11357-6.

Q: What calibration is required?

A: Temperature calibration uses certified reference materials (indium, tin, lead, zinc) with known melting points. 

Enthalpy calibration uses indium's known heat of fusion (28.45 J/g). Calibration should be performed at the same 

heating rate used for testing. We recommend recalibration every 6 months or when changing temperature range.

Packing Information:

Quantity: 1

Dimensions/Gross weight :560x 500 x 500mm/25kg