Research data for manuscript: The influence of the graft rigidity on the dynamical behavior of PMMS-based polymer brushes at ambient and high pressure

The dataset contains raw dielectric and calorimetric measurement data, presented in the manuscript entitled "The influence of the graft rigidity on the dynamical behavior of PMMS-based polymer brushes at ambient and high-pressure". In this work, we investigated the molecular dynamics of oligomeric brushes based on poly(mercaptopropyl)methylsiloxane (PMMS) grafted with acrylate and methacrylate monomers of of varying molecular weight at different thermodynamic conditions. The calorimetric studies performed showed that the glass transition temperature (Tg) depends on the strain chain length and steric hindrance applied in the grafting process (these effects are enhanced with chain growth). The dielectric studies revealed the presence of two relaxation processes - 𝛼 and 𝛼', in the group of polymers grafted with methacrylates and one broad relaxation 𝛼 process in the group grafted with acrylates. The faster 𝛼 relaxation process in both groups of compounds originates from the segmental movements. Further high-pressure studies have shown that there is a superposition between the 𝛼-segmental process and the 𝛼'-process regardless of the applied pressure. This behavior may suggest that the slower 𝛼' mode originates from the sub-Rouse type (sub)chain unit motions (similar to the case of PMMS homopolymer). However, further studies should be performed to better understand the influence of the topology and architecture of the strains on the molecular dynamics of the polymers and the correlation between them.