Poly(methyl acrylate- co-sodium methacrylate) ionomer studied by solid state 13C T1ρ NMR
Abstract
The poly(methyl acrylate) (PMA) and poly(methyl acrylate- co-sodium methacrylate) containing 6.9 mol% of ionic groups (PMANa-6.9) were studied by 13C CP/MAS NMR. The 13C spin-lattice relaxation times in a rotating frame, T1ρ, have been measured as a function of temperature. Using these T1ρ spin-lattice relaxation times, we discuss the mobility, the correlation time, and activation energy for the PMA and PMANa-6.9, respectively. The molecular motion in the PMANa-6.9 needs higher activation energies than in PMA. It is worth noting that the motion of the 1-methyl carbons in the PMANa-6.9 ionomer distinctly differs from that in the PMA homopolymer. The slow side of the T1ρ minimum associated with the 1-methyl carbons is ascribed to stronger interactions between the polymer chains in the ionomer than in the homopolymer.
- Publication:
-
Solid State Communications
- Pub Date:
- June 2000
- DOI:
- 10.1016/S0038-1098(00)00164-2
- Bibcode:
- 2000SSCom.115..179L