Polymer Engineering and Science, Vol.41, No.2, 262-274, 2001
Viscoelastic properties of reactive and non-reactive blends of ethylene-methyl acrylate copolymers with styrene-maleic anhydride copolymer
The effects of compatibilizing reactions on the viscoelastic properties and morphology of ethylene-methyl acrylate copolymers were studied. Potentially reactive blends of styrene-maleic anhydride copolymer (SMAH) and a terpolymer of ethylene/methyl acrylate/glycidyl methacrylate (E-MA-GMA) were compared with a nonreactive blend of SMAH and an ethylene/methyl acrylate (E-MA) copolymer with similar rheological properties. Melt mixing was carried out in a batch mixer and in a co-rotating twin screw extruder. The morphology of the reactive blends showed smaller domain sizes than the non-reactive blends, and the viscoelastic properties of the blends were very different. The storage and loss moduli and the complex viscosity of the reactive blends were greater than those of non-reactive blends. The reactive blends had a higher zero shear viscosity, plateau modulus and mean relaxation time than their non-reactive counterparts, indicating a higher degree of melt elasticity. The melt elasticity was maximum at 25% functionalized ethylene-methyl acrylate concentration.