Phase separation behavior of encapsulated liquid crystals in monodispersed acetalized poly(methylmethacrylate) particles

To improve the degree of phase separation between polymer and LC in LC microcapsules, poly(methylmethacrylate-co-vinylacetate) substrate particles were acetalized by using aldehydes having a different chain length. LC microcapsules were prepared by the solute co-diffusion method (SCM). The phase separation behavior was evaluated with a differential scanning calorimeter (DSC). The degree of phase separation between LC and substrate particles modified with butyl aldehyde was relatively high in comparison with those modified with hexanal and octanal. This means that poly(vinylbutyral) (PVB) moiety in substrate particles causes the complete phase separation and a single LC domain formation. On the contrary, as the aldehyde chain lengthened, the phase separation of LC domain was inhibited.