Low molar mass liquid crystals with phase properties similar to polymers may be obtained by the addition of a disiloxane tail to an organic mesogen. We present a comparison of the properties of two chiral mesogens (based on the 4-((S)(+) 2-Methylbutanoyloxy)phenyl 4-(9-decenyloxy)benzoate and 4-((2S)-2-Chloro-3-methylbutanoyl)phenyl 4’-(9-decenyloxy)benzoate moieties) with and without a pentamethyl disiloxane tail and with their vinyl-terminated analogues. We show a general decrease in transition temperatures, and a widening of the mesophase range in the disiloxane-substituted materials due to a suppression of the crystallisation temperature. The phases exhibited are modified, with a tilted smectic-C phase favoured on substitution of the disiloxane tail, eliminating the smectic-A phase found in the unsubstituted mesogen; this gives high tilt angle (28-36 degrees) single mesophase materials. We summarise the electro-optic properties of a series of the disiloxane-substituted materials, which show low viscosity (similar to 500mPas) and moderate spontaneous polarisation (20-150nCcm-(2)) across the range of materials, and show their variation with temperature. We demonstrate the variations of these properties with varying alkyl spacer length, alkyl tail length and changing chiral end-group.