Synthesis and properties of bioinspired silica filled polydimethylsiloxane networks.

摘要

We have incorporated bioinspired silica fillers into poly (dimethylsiloxane) (PDMS) elastomers and investigated their mechanical, morphological and thermal properties as a function of filler loading. The equilibrium stress-strain characteristics of the elastomers were determined as a function of bioinspired filler loading and the Mooney-Rivlin constants (2C1 and 2C 2) were calculated from the stress-strain isotherms. The thermal characteristics, in particular the glass transition temperature (Tg) and the melting point (Tm) of the elastomers were characterized using differential scanning calorimetry (DSC). We have also synthesized poly (propyleneoxide) (PPO) hybrid networks by incorporating bioinspired silica as a filler. The high temperature thermal stability of PDMS networks and PPO networks were investigated and compared using thermogravimetric analysis (TGA). In previous studies a mechanism was proposed explaining the formation of these new silica structures which is based on the silica incorporating the (bio)macromolecule. The results obtained from thermogravimetric analysis strengthen the "proposed mechanism" of formation of these new bioinspired silica structures. The morphology of the samples and the filler dispersion were characterized using Scanning Electron Microscopy (SEM).; Although only spherical silica particles were used here as reinforcement, however this bioinspired synthetic route also enables highly asymmetric silica structures to be prepared. This methodology therefore offers the interesting possibility of preparing hybrid systems where the properties of these new hybrids are highly anisotropic. (Abstract shortened by UMI.)