Thermal properties, miscibility and specific interactions in comparison of linear and star poly(methyl methacrylate) blend with phenolic

A series of miscible linear and star poly(methyl methacrylate) (PMMA)/phenolic blends with different compositions have been prepared. Tgs of both systems are negative derivation from the average values, implying that the self-association interaction is stronger than the inter-association interaction between linear or star PMMA with phenolic. The proton spin–lattice relaxation time in the rotating frame (T1ρH) determined by high resolution solid state 13C NMR indicates single composition dependent T1ρH from all blends, implying a good miscibility with chain dynamics on a scale of 1–2 nm. However, T1ρHs of star PMMA/phenolic blends are relatively smaller than those of linear PMMA/phenolic blends, implying that the degree of homogeneity of star PMMA/phenolic blends is higher than those of linear PMMA/phenolic blends. According to FT-IR analyses, the above results can be rationalized that the hydrogen-bonding interaction of the star PMMA/phenolic blends is greater than the corresponding linear PMMA/phenolic blends.