The thermal properties of the pure polymers, elastomers and the blends containing 1 wt% P3HT were measured using differential scanning calorimetry (DSC), using a heating rate of 10 °C min -1 under helium atmosphere (Figure , Table and). Firstly, the thermal transitions of the precursor PDMS-OH polymers were compared to discern the effects of molar mass on thermal properties between LPDMS-OH and HPDMS-OH. In the cooling cycle for LPDMS-OH, an exothermic peak at -92 °C was assigned to polymer crystallisation (Tc) with an associated enthalpy change (ΔHc) of 12.2 J g -1 and a step change at -126 °C due to a change in heat capacity at the glass transition temperature (Tg). The same crystallisation event was observed for HPDMS-OH, albeit at a lower temperature (Tc = -72 °C; ΔHc = 24.4 J g -1 ). The glass transition temperature (Tg) was again observed around -125 °C, however, the associated step change associated was significantly less pronounced. In the heating cycle three distinct events were observed for both LPDMS-OH and HPDMS-OH: a glass transition (Tg), an exothermic peak associated with cold crystallisation (Tcc) and a bimodal endothermic peak as a result of polymer melting (Tm).