Polymerization Of Β-butyrolactone Research Articles

Stereoselective Ring-Opening (Co)polymerization of β-Butyrolactone and ε-Decalactone Using an Yttrium Bis(phenolate) Catalytic System.

An effective route for ring-opening copolymerization of β-butyrolactone (BBL) with ε-decalactone (ε-DL) is reported. Microstructures of the block copolymers characterized by 13C NMR spectroscopy revealed syndiotactic-enriched poly(3-hydroxybutyrate) (PHB) blocks. Several di- and triblock copolymers (PDL-b-PHB and PDL-b-PHB-b-PDL, respectively) were successfully synthesized by sequential addition of the monomers using (salan)Y(III) complexes as catalysts. The results from MALDI-ToF mass spectrometry confirmed the presence of the copolymers. Moreover, thermal properties of the block copolymers were also investigated and showed that the microphase separation of PDL-b-PHB copolymers into PHB- and PDL-rich domains has an impact on the glass transition temperatures of both blocks.

Salen Complexes of Zirconium and Hafnium: Synthesis, Structural Characterization, Controlled Hydrolysis, and Solvent-Free Ring-Opening Polymerization of Cyclic Esters and Lactides

Dinuclear salen compounds of zirconium and hafnium are efficient initiators for the solvent-free ring-opening polymerization of cyclic ester monomers and lactides. There is a correlation between the theoretical and experimental number-average molecular weights (M(n)'s) in these polymerizations. Polymerization of β-butyrolactone gives poly(3-hydroxybutyrate) with a good M(n) and molecular weight distribution.

Bis(imino)phenoxide complexes of zirconium: synthesis, structural characterization and solvent-free ring-opening polymerization of cyclic esters and lactides

Bis(imino)phenoxide complexes of zirconium possess spectacular reactivity towards the solvent-free polymerization of cyclic ester monomers and lactides. Polymerization of lactide is living and the resulting product has exceptionally high number average molecular weights (Mn). Polymerization of β-butyrolactone gives syndiotactic poly(3-hydroxybutyrate) with good Mn and molecular weight distribution (MWD).

The molecular structure of (R,S)-[Al6But6(μ3-O)4{μ3-O2CCH2C(H)(Me)O}2]: evidence for the latent Lewis acid catalyzed polymerization of (R,S)-β-butyrolactone

The reaction of [ButAl(µ3-O)]6 with 2 equiv. of (R,S)-β-butyrolactone resulted in the formation of the alumoxane, (R,S)-[Al6But6(µ3-O)4{µ3-O2CCH2C(H)(Me)O}2], with a molecular structure consisting of two ring-opened lactone moieties inserted into, and bridging, the edge of the Al6O6 alumoxane. The role of this alumoxane in the latent Lewis acid catalyzed ring-opening polymerization of β-butyrolactone is discussed.