Effect of the Interfacial Structure on the Local Dynamics of Poly(methyl methacrylate)-Silica Hybrids

Poly(methyl methacrylate-maleic anhydride)-silica hybrid materials, P(MMA-MA5)-SiO₂, were synthesized from the in situ reaction of methyl methacrylate (MMA) with 5 mol % maleic anhydride (MA),then hydrolyzed with 3-amino-propyl methyl diethoxysilane (APrMDEOS) coupling agent and tetraethoxysilane (TEOS) by asol-gel process. By the same method, the poly(methyl methacrylate-glycidyl methacrylate)-silica hybrids (P[MMA-GMA5]-SiO₂), reacted with 5 mol % glycidyl methacrylate (GMA), were obtained. The structure and relaxation of the hybrids were characterized by IR, and ²⁹Si- and ¹³C-NMR spectroscopy. The effect of the interfacial structure on the local dynamics of the hybrids was investigated using the ²⁹Si-¹H cross-polarization and proton spin-lattice relaxation time in the rotation frame.