Overview
Differential scanning calorimetry is a technique in which the difference between the rate of flow of heat into a specimen crucible containing the specimen and that into a reference crucible is derived as a function of temperature and/or time while the specimen and reference are subjected to the same controlled temperature programme in a specified atmosphere using a symmetrical measurement system. It is a highly precise thermal analysis technique used to measure how a material’s heat flow changes as a function of temperature or time. It plays a critical role in understanding the thermal behavior of materials such as plastics, polymers, packaging materials, oils, pharmaceuticals, and specialty chemicals. According to the principles of thermodynamics, energy absorbed by a system is considered positive while energy released is negative. This approach implies that the endothermic direction points upwards in the ordinate and the exothermic direction downwards. It also has the advantage that the direction of thermal effects in plots of heat flow rate and specific heat is consistent.
DSC enables the identification of thermal transitions including melting, crystallization, glass transition, curing, and decomposition. It is widely used in research, quality control, and product development across multiple industries.
Objective of DSC Testing
The primary objectives of DSC analysis include:
- Determining thermal transitions (melting point, glass transition temperature, crystallization)
- Evaluating material purity and composition
- Measuring heat capacity and enthalpy changes
- Assessing thermal stability and degradation behavior
- Studying curing kinetics of resins and polymers
- Comparing batch-to-batch consistency for quality assurance
Key Testing Parameters
DSC testing provides a wide range of measurable parameters:
- Glass Transition Temperature (Tg)
- Melting Temperature (Tm)
- Crystallization Temperature (Tc)
- Heat of Fusion / Enthalpy (ΔH)
- Oxidation Induction Time (OIT)
- Specific Heat Capacity (Cp)
- Degree of Crystallinity
- Curing Temperature and Reaction Enthalpy
Materials Tested
Our DSC services support a broad spectrum of materials, including:
- Plastics & Polymers (PE, PP, PET, PVC, engineering plastics)
- Packaging Materials (films, laminates, multilayer structures)
- Oils & Lubricants
- Pharmaceuticals & Medicines (API and formulations)
- Rubbers & Elastomers
- Adhesives & Coatings
- Food Products & Specialty Chemicals
Standards & Test Methods
We conduct DSC testing in accordance with internationally recognized standards:
ASTM/ISO Standards
- ASTM D3418 – Transition Temperatures and Enthalpies of Polymers
- ASTM D3895 / D4565 – Oxidation Induction Time (OIT)
- ASTM E1356 – Glass Transition Temperature
- ASTM E793 – Enthalpies of Fusion and Crystallization
- ASTM E1269 – Specific Heat Capacity
- ISO 11357 (Parts 1–7) – Plastics – DSC Analysis
All testing is performed using calibrated instruments under controlled conditions to ensure accuracy and repeatability.
Data Analysis & Interpretation
DSC generates a thermogram (heat flow vs. temperature curve), which is analyzed to extract meaningful insights:
- Identification of transition peaks (endothermic/exothermic events)
- Determination of onset, peak, and endset temperatures
- Calculation of enthalpy values (area under peaks)
- Evaluation of crystallinity percentage
- Comparison with reference materials or previous batches
Advanced software tools are used for precise curve fitting, baseline correction, and kinetic modelling where required.