Star Telechelic Poly(l-lactide) Ionomers.

Poly(l-lactide) (PLA), a biodegradable and biorenewablepolymer, has many excellent properties that are equivalent to thoseof petroleum-derived plastics such as polystyrene, aromatic polyesters,etc. However, a major disadvantage of PLA which limits its processabilityis its poor melt elasticity. In this work we explore the possibilityof improving the viscoelastic properties of PLA melt by incorporatingionic groups on the polymer. Specifically, we demonstrate the synthesisof star telechelic PLA anionomers by a three-step procedure involvingsynthesis of Star PLA, converting the hydroxyl end groups into carboxylicacid end groups, and finally converting these into ionic groups. Rheologydata showed a dramatic increase in the elasticity of the star telechelicionomer melts relative to the Star PLA melts. The viscoelasticityof star telechelic ionomers melts could be modulated by varying thenumber of ionic groups per molecule. [ABSTRACT FROM AUTHOR]