Designing Cure Kinetics in Polyester Networks: Tuning Initiator Content to Control Gelation and Glass-Transition Development
- 1KTH Royal Institute of Technology
Abstract
Unsaturated polyester networks remain widely used in composite manufacturing, construction, and infrastructure, and yet the practical relationship between initiator content and cure trajectory is not always reported consistently across industrial formulations. Using a field-representative unsaturated polyester systems, real-time gelation/exotherm were tracked with differential scanning calorimetry (DSC) to map how initiator type and content govern gel time, exotherm behavior, and the thermal state of the cured network. Across the compositions examined, gel time varied roughly four-fold, from approximately 10–12 minutes to 44–45 minutes, and peak exotherm temperature reached approximately 123–137 °C. Across an extended 0.8–4% peroxide range, the first-scan glass transition (Tg1) rose from 46.15 to 56.38 °C and residual cure enthalpy (ΔH) fell from 33.35 to 15.67 J/g, while the fully cured glass transition (Tg2) rose sharply to approximately 100–103 °C at intermediate peroxide content before declining to 84.74–89.20 °C at 3–4%. These results indicate that additional initiator can accelerate cure and reduce measured residual reaction while not necessarily improving the final thermal state of the network.
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BibTeX
@misc{kharazmi2026designing,
title = {{Designing Cure Kinetics in Polyester Networks: Tuning Initiator Content to Control Gelation and Glass-Transition Development}},
author = {Parastou Kharazmi},
howpublished = {ChemRxiv},
year = {2026},
month = sep,
doi = {10.26434/chemrxiv.15009170/v1},
url = {https://chemrxiv.org/doi/full/10.26434/chemrxiv.15009170/v1},
note = {CC BY},
}
RIS
TY - UNPB
TI - Designing Cure Kinetics in Polyester Networks: Tuning Initiator Content to Control Gelation and Glass-Transition Development
AU - Parastou Kharazmi
PY - 2026
DA - 2026/09/21
PB - ChemRxiv
DO - 10.26434/chemrxiv.15009170/v1
UR - https://chemrxiv.org/doi/full/10.26434/chemrxiv.15009170/v1
AB - Unsaturated polyester networks remain widely used in composite manufacturing, construction, and infrastructure, and yet the practical relationship between initiator content and cure trajectory is not always reported consistently across industrial formulations. Using a field-representative unsaturated polyester systems, real-time gelation/exotherm were tracked with differential scanning calorimetry (DSC) to map how initiator type and content govern gel time, exotherm behavior, and the thermal state of the cured network. Across the compositions examined, gel time varied roughly four-fold, from approximately 10–12 minutes to 44–45 minutes, and peak exotherm temperature reached approximately 123–137 °C. Across an extended 0.8–4% peroxide range, the first-scan glass transition (Tg1) rose from 46.15 to 56.38 °C and residual cure enthalpy (ΔH) fell from 33.35 to 15.67 J/g, while the fully cured glass transition (Tg2) rose sharply to approximately 100–103 °C at intermediate peroxide content before declining to 84.74–89.20 °C at 3–4%. These results indicate that additional initiator can accelerate cure and reduce measured residual reaction while not necessarily improving the final thermal state of the network.
ER -