SMA-graft- PEG copolymers were synthesized as novel polymeric S-SPCMs<. The S-SPCMs show phase transitions in the temperature range of about 40–45 °C<. The S-SPCMs had high latent heat capacity between 107 and 155 J g−1<. The S-SPCMs had good thermal reliability and thermal durability<. The S-SPCMs had good TES potential for passive solar heating and cooling applications<.