Side-chain fluorination effects on morphological behavior of symmetric polystyrene-b-poly(tert-butyl methacrylate) (PS-b-PtBMA) was investigated using small angle X-ray scattering, where the tBMA units were partially modified into 2,2,2-trifluoroethyl methacrylate (TFEMA) and methacrylic anhydride (MAA) units to form PS-b-P(tBMA-r-TFEMA-r-MAA)s. Above 50% fluorination from 7.8 kg/mol PS-b-PtBMA, a lamellar structure was identified over the entire temperature range up to 240oC. However, a 36% fluorination product exhibited the morphological transition from cylindrical to gyroid structures further to disordered state with increasing temperature. This abnormal phase stability was attributed presumably to a transient increase in conformational asymmetry that creates spontaneous interfacial curvatures between the two blocks.
All Science Journal Classification (ASJC) codes
- Polymers and Plastics
- Organic Chemistry
- Materials Chemistry