New ‘side-on’ attached liquid crystal polysiloxanes have been synthesized with different fixation ratios of side groups and various degrees of polymerization. For these syntheses, a series of random copoly(hydrogenmethyl-dimethylsiloxane)s, used a precursors, has been realized. Both thermal properties and small angle neutron scattering experiments on these polymers show a dècrease in the nematic ‘jacketed’ effect as the number of mesogenic groups fixed to the backbone decreases and as the main chain length increases.