Miscibility in blends of poly(methyl methacrylate) and poly(silyl ether) as investigated by DSC and ¹³C CP/mas Nmr spectroscopy

Miscibility and phase behavior in blends of poly(silyl ether) (PSE) and poly(methyl methacrylate) (PMMA) were investigated by thermal analysis and high-resolution solid-state nuclear magnetic resonance (NMR) spectroscopy. The blends displayed single, composition-dependent glass transition temperatures (T g 's), indicating that the blend system is miscible for all compositions. To examine the miscibility at the molecular level, high-resolution solid-state 13 C NMR spectroscopy was used. The proton spin-lattice relaxation time T 1 (H) and the proton spin-lattice relaxation time in the rotating frame T 1ρ (H) were measured via 13 C cross-polarization/magic angle spinning NMR as functions of blend compositions. In light of the proton spin-lattice relaxation parameters, it is concluded that the PSE and PMMA chains are intimately mixed on the scale of 20-30 Å.