DSC and MDSC Thermal Analysis of Bituminous Binders, RAP, and Wax-Modified Binders

Dataset Description

This repository contains differential scanning calorimetry (DSC) and modulated differential scanning calorimetry (MDSC) data generated during the development of an enhanced thermal analysis framework for bituminous binders, reclaimed asphalt pavement (RAP), and wax-modified binders.

Materials

The dataset covers a range of materials, including straight-run bituminous binders, recovered RAP binders, pure waxes, and wax-modified binders. The measurements provide information on glass transitions, crystallisation, cold crystallisation, melting behaviour, and changes in apparent heat capacity. The dataset therefore supports the investigation of thermal behaviour beyond the conventional evaluation of glass-transition temperature and heat-capacity change.

Methods

The measurements in this repository can be reproduced using conventional DSC and MDSC under comparable conditions. For bituminous binders, approximately 5–10 mg of sample can be measured in perforated aluminium crucibles. For conventional DSC, samples are heated from 30 to 150 °C at 50 K/min, held for 2 min, cooled to −80 °C at 10 K/min, held isothermally for 10 min, and reheated to 150 °C at 10 K/min. The cycle can be repeated once before a final cooling step to 30 °C.

For pure waxes, approximately 3–5 mg of sample can be used, with a temperature range selected according to the melting range of the material (approximately 0–100 °C for low-melting waxes and 30–175 °C for high-melting waxes). 

For MDSC, heating measurements can be performed at 2 K/min using a 60 s modulation period and 0.3 °C amplitude (to prevent the modulations causing cooling during the heating ramp), while the cooling procedure is kept consistent with the conventional DSC measurements to obtain comparable crystal structures. These conditions are provided as a practical reproduction of the measurements used for the present dataset; variations in instrument, calibration, sample mass, crucible configuration, and measurement parameters may affect the resulting heat-flow response.

Framework Description

The repository provides the measurement data in a simplified and consistently structured form. The original measurement sequences have been reduced to the relevant cooling and heating cycles, allowing the thermal response of the different materials to be compared and analysed directly.

In addition to the experimental data, the repository includes the preliminary analysis workflow used to extract thermal features from conventional DSC measurements. The analysis is provided step by step to make the assumptions, intermediate results, and processing of the DSC signals transparent. The current workflow is divided into the following stages:

1. Data preprocessing and spike detection/removal
   The measurement data are first converted to a consistent time/temperature representation and inspected for isolated signal spikes and other short-duration artefacts. Detected spikes are removed and replaced using a third-order polynomial interpolation. Example plots are provided to illustrate the detected artefacts and the resulting cleaned heat-flow signal.
2. Heat-capacity baseline fitting
   Determination of apparent heat-capacity baselines for the cooling and heating cycles and estimation of the corresponding heat-capacity changes and temperature-dependent slopes.
3. Glass-transition and cooling-crystallisation detection
   Identification and fitting of glass-transition contributions and crystallisation events during cooling using the baseline-corrected heat-flow response and its derivative.
4. Heating non-reversing heat flow and melting/cold-crystallisation mapping
   Reconstruction of the reversing heat-flow contribution and separation of the heating signal into reversing and non-reversing components. The non-reversing response is subsequently used to identify cold crystallisation and melting events and to determine their corresponding enthalpies.
5. Wax additive dosage estimation
   Comparison of the thermal response of wax-modified binders with the corresponding unmodified binder and pure wax. The additional melting/crystallisation enthalpy is used to estimate the contribution of the added wax and, where applicable, provide an approximate estimate of the wax dosage.

Comparison with MDSC

MDSC measurements are included as a complementary dataset. The reversing and non-reversing heat-flow signals obtained from MDSC are used to investigate the interpretation of overlapping thermal events and to compare them with the contributions predicted from conventional DSC. The MDSC data are intended as a complementary reference rather than as a quantitative validation of the current DSC-based procedure, as the comparison can be affected by experimental and instrumental parameters.

Data Format

For ease of use and further analysis, the raw measurement data and extracted thermal parameters are provided in CSV and JSON format, allowing straightforward extraction, comparison, and processing in common data-analysis software. The figures provided with the dataset are supplied as SVG files, preserving the original vector resolution and allowing the plots to be inspected, scaled, or reused without loss of image quality.

Purpose

Overall, the repository provides both the underlying thermal measurement data and the processing steps used to derive the reported thermal features, enabling users to inspect the data, reproduce the current analysis, test alternative approaches, and contribute to the further development of standardised DSC testing and analysis of bituminous and wax-modified materials.

Acknowledgements

The authors gratefully acknowledge the financial support of the Austrian Federal Ministry for Digital and Economic Affairs, the National Foundation for Research, Technology and Development, and the Christian Doppler Research Association. The authors also thank the CD Laboratories company partners BMI Group, OMV Downstream, and Pittel + Brausewetter for their support.