The synthesis of hydroxymethylfuroate macrocyclic oligoesters c(HMF)n promoted by an N-heterocyclic carbene (NHC) organocatalyst is herein presented together with the subsequent organocatalytic, entropically- driven ring-opening polymerization (ED-ROP) leading to the fully furan-based poly(hydroxymethylfuroate) (PHMF). The target macrocycles (mostly trimer and tetramer species) have been obtained directly from the platform chemical HMF (77% isolated yield) under high dilution conditions using a quinone as the external oxidant and the green solvent Me-THF. The ED-ROP of c(HMF)n has been optimized at 160 °C (melt condensation technique) with the couple triazabicyclodecene (TBD)/n-octanol (1 : 1) as catalyst/initiator of the polymerization process in the presence of commercial antioxidants Irganox 1010 (0.1% w/w) and Irgafos 126 (0.3% w/w) to suppress degradation side reactions. Under these conditions, the bio-based PHMF (poly-HMF) was obtained as a color-free polymer with number-average molecular weight up to 48 600 g mol−1 and dispersity between 1.5 and 1.9 as determined by NMR and GPC analyses. The thermal behavior of the novel furan-based polyester PHMF was investigated (TGA and DSC analyses) observing a good thermal stability (onset temperature of degradation ∼310 °C) and a semicrystalline structure with melting temperature above 160 °C when processed from solvent, thus making PHMF a promising material for processing as other commercial polyesters.
Ragno, D., Di Carmine, G., Vannini, M., Bortolini, O., Perrone, D., Buoso, S., et al. (2022). Organocatalytic synthesis of poly(hydroxymethylfuroate) via ring-opening polymerization of 5-hydroxymethylfurfural-based cyclic oligoesters. POLYMER CHEMISTRY, 13, 1-9 [10.1039/D1PY01687C].
Organocatalytic synthesis of poly(hydroxymethylfuroate) via ring-opening polymerization of 5-hydroxymethylfurfural-based cyclic oligoesters
Vannini, Micaela;
2022
Abstract
The synthesis of hydroxymethylfuroate macrocyclic oligoesters c(HMF)n promoted by an N-heterocyclic carbene (NHC) organocatalyst is herein presented together with the subsequent organocatalytic, entropically- driven ring-opening polymerization (ED-ROP) leading to the fully furan-based poly(hydroxymethylfuroate) (PHMF). The target macrocycles (mostly trimer and tetramer species) have been obtained directly from the platform chemical HMF (77% isolated yield) under high dilution conditions using a quinone as the external oxidant and the green solvent Me-THF. The ED-ROP of c(HMF)n has been optimized at 160 °C (melt condensation technique) with the couple triazabicyclodecene (TBD)/n-octanol (1 : 1) as catalyst/initiator of the polymerization process in the presence of commercial antioxidants Irganox 1010 (0.1% w/w) and Irgafos 126 (0.3% w/w) to suppress degradation side reactions. Under these conditions, the bio-based PHMF (poly-HMF) was obtained as a color-free polymer with number-average molecular weight up to 48 600 g mol−1 and dispersity between 1.5 and 1.9 as determined by NMR and GPC analyses. The thermal behavior of the novel furan-based polyester PHMF was investigated (TGA and DSC analyses) observing a good thermal stability (onset temperature of degradation ∼310 °C) and a semicrystalline structure with melting temperature above 160 °C when processed from solvent, thus making PHMF a promising material for processing as other commercial polyesters.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
