The goal of this present work was to compare the properties of dimers with a siloxane spacer to those of side chain polysiloxanes including the same mesogenic groups and the same dilution with dimethylsiloxane segments. A systematic study of the influence of the dilution parameter on the mesomorphic and structural properties of dimers and diluted side chain polysiloxanes, as well as on the behaviour of their solutions with low molar mass liquid crystals is reported.