An article entitled "Biobased poly(butylene 2,5-furandicarboxylate) and poly(butylene adipate-co-butylene 2,5-furandicarboxylate)s: From synthesis using highly purified 2,5-furandicarboxylic acid to thermo-mechanical properties" published in Polymer (2014)
To synthesize high quality (co)polyesters derived from 2,5-furandicarboxylic
acid (FA), an acetic acid refluxing/pH-swing method was proposed to purify FA. 2-Carboxyl
furfural and other impurities were removed completely from FA with this method.
Using highly purified FA, biobased polyester poly(butylene furnadicarboxylate)
(PBF) and aliphatic-aromatic copolyesters poly(butylene adipate-co-butylene 2,5-furandicarboxy-late)s
(PBAFs) were synthesized via melt (co)polycondensation. The (co)polyesters were
characterized with GPC, FTIR, 1H NMR, DSC and TGA, and their tensile
mechanical properties were also assessed. The copolyesters possess random chain
structure, monomer feed ratio-controlled copolymer composition and excellent
thermal stability (Td,5% > 340 oC) in full composition
range. Both BA-rich and BF-rich PBAFs are crystalline polymers. The
crystallizability decreases with composition, up to nearly amorphous at
moderate ?BF (40-60%).
PBAFs with ?BF no more
than 50% exhibit obvious high-elastic deformation and rebound resilience, and
possess tensile properties (E 18-160
MPa, sb 9-17 MPa, eb 370-910%) comparable to
poly(butylene adipate). PBAFs with higher ?BF behave like nonrigid plastics with low tensile moduli (42-110 MPa), moderate
strength (30-42 MPa) and high elongation at break (310-470%). In comparison,
PBF is a strong and tough thermoplastic having balanced mechanical properties,
namely, much higher tensile modulus (1.9 GPa) and strength (56 MPa) and high
elongation at break (260%). It seems necessary and effective to use highly
purified FA for synthesizing high performance FA-derived (co)polyesters.