ja6b07287_si_002.cif (222.07 kB)
Tailor-Made Stereoblock Copolymers of Poly(lactic acid) by a Truly Living Polymerization Catalyst
dataset
posted on 2016-09-07, 00:00 authored by Tomer Rosen, Israel Goldberg, Vincenzo Venditto, Moshe KolPoly(lactic acid) (PLA) is a biodegradable
polymer prepared by
the catalyzed ring opening polymerization of lactide. An ideal catalyst
should enable a sequential polymerization of the lactide enantiomers
to afford stereoblock copolymers with predetermined number and lengths
of blocks. We describe a magnesium based catalyst that combines very
high activity with a true-living nature, which gives access to PLA
materials of unprecedented microstructures. Full consumption of thousands
of equivalents of L-LA within minutes gave PLLA of expected molecular
weights and narrow molecular weight distributions. Precise PLLA-b-PDLA diblock copolymers having block lengths of up to
500 repeat units were readily prepared within 30 min, and their thermal
characterization revealed a stereocomplex phase only with very high
melting transitions and melting enthalpies. The one pot sequential
polymerization was extended up to precise hexablocks having “dialed-in”
block lengths.
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L-LAblock lengthslactide enantiomersTailor-Made Stereoblock Copolymersring opening polymerizationacidweight distributionsPLA materialssequential polymerizationFull consumptionPDLA diblock copolymersPrecise PLLAstereoblock copolymerscatalysttrue-living naturestereocomplex phasepot sequential polymerizationPoly30 min