(217fk) Synthesis and Characterization of a Polysiloxane Based Magnetic Liquid Crystalline Elastomer Composite

Liquid crystalline elastomers (LCE´s) are liquid crystal polymers that combine the mechanical properties of rubbers with the ordered structure and mobility of LC phases. They have unique optical, mechanical and piezoelectric properties, which can be modified in response to external stimuli. The latter allows for potential applications such as mechanical actuators, in optics and sensing. In this work, we propose to improve the sensitivity of these elastomers to external stimuli by triggering mechanical and optical responses through external magnetic fields or viceversa. In order to do this, we are embedding into the LC elastomer chemically functionalized magnetic particles.

Polysiloxanes are ideal candidates due to their biocompatibility and known chemical synthesis and modification. The proposed liquid crystalline elastomer consist of a polysiloxane backbone poly(methylhydrosiloxane), a mesogenic pendant group 4-methoxyphenyl-4(but-3-enyloxy)benzoate, and a bifunctional crosslinker 1,4-bis(undecyl-10-enyloxy)benzene. Preliminary results for the synthesis and characterization by DSC, infrared spectroscopy, NMR and polarized optical microscopy of the precursors, the liquid crystalline elastomer and the corresponding composite prepared with 3-(trimethoxysylil)propyl methacrylate (MPS) functionalized magnetic particles will be presented.