Gradient terpolymers with long ε-caprolactone rich sequence derived from propylene oxide, CO2, and ε-caprolactone catalyzed by zinc glutarate

Compatibilization of the poly(lactic acid)/poly(propylene carbonate) blends through in situ formation of poly(lactic acid)‐b‐poly(propylene carbonate) copolymer

“…Generally speaking, the C NMR was a much sensitive method to distinguish between a block and random copolymer via the difference of carbonyl signal. Therefore a C NMR investigation was brought on the pure PLA, PPC, and reaction samples.…”

“…Generally speaking, the C NMR was a much sensitive method to distinguish between a block and random copolymer via the difference of carbonyl signal. Therefore a C NMR investigation was brought on the pure PLA, PPC, and reaction samples. As Figure (a) showed, the C NMR signals in different structural fragment of pure PLA chain (a′–c′) and PPC chain (a–d) were detected clearly and marked, respectively.…”

“…Therefore a C NMR investigation was brought on the pure PLA, PPC, and reaction samples. As Figure (a) showed, the C NMR signals in different structural fragment of pure PLA chain (a′–c′) and PPC chain (a–d) were detected clearly and marked, respectively. From previous analyses of GPC, A40C60–0.5T might have the higher transesterification level among all samples, therefore its C NMR spectra was provided in Figure (b) as an illustration and the C NMR spectra of A40C60–0 was also given as a contrast.…”

“…The chain structures of transesterification samples were characterized by a 400 MHz C nuclear magnetic resonance (NMR) spectroscopy (AV400, Bruker, Germany). Deuterated chloroform (CDCl 3 ) was used as the solvent for the NMR characterization at room temperature, and the peak position were reported with respect to tetramethylsilane.…”

“…Poly(propylene carbonate) (PPC) is also a biodegradable polyester attracting great research attention and known as a two‐way green environmental protection material deriving from carbon dioxide (CO 2 ) and propylene oxide . While different from PLA, PPC exhibits excellent tensile toughness but low strength, which is just complementary with the high mechanical strength but poor toughness of PLA. In the meanwhile, the relatively low gas permeability of PPC is very useful for its application in biodegradable packaging products.…”