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Synthetic Strategy for Preparing Chiral Double-semicrystalline Polyether Block Copolymers.

ABSTRACT: We report an effective strategy for the synthesis of semi-crystalline block copolyethers with well-defined architecture and stereochemistry. As an exemplary system, triblock copolymers containing either atactic (racemic) or isotactic (R or S) poly(propylene oxide) end blocks with a central poly(ethylene oxide) mid-block were prepared by anionic ring-opening procedures. Stereochemical control was achieved by an initial hydrolytic kinetic resolution of racemic terminal epoxides followed by anionic ring-opening polymerization of the enantiopure monomer feedstock. The resultant triblock copolymers were highly isotactic (meso triads [mm]% ~ 90%) with optical microscopy, differential scanning calorimetry, wide angle x-ray scattering and small angle x-ray scattering being used to probe the impact of the isotacticity on the resultant polymer and hydrogel properties.

SUBMITTER: McGrath AJ

PROVIDER: S-EPMC4408015 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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Synthetic Strategy for Preparing Chiral Double-semicrystalline Polyether Block Copolymers.

McGrath Alaina J AJ Shi Weichao W Rodriguez Christina G CG Kramer Edward J EJ Hawker Craig J CJ Lynd Nathaniel A NA

Polymer chemistry 20150301 9

We report an effective strategy for the synthesis of semi-crystalline block copolyethers with well-defined architecture and stereochemistry. As an exemplary system, triblock copolymers containing either atactic (racemic) or isotactic (<i>R</i> or <i>S</i>) poly(propylene oxide) end blocks with a central poly(ethylene oxide) mid-block were prepared by anionic ring-opening procedures. Stereochemical control was achieved by an initial hydrolytic kinetic resolution of racemic terminal epoxides follo ...[more]

PMID: 25914726

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