Thermal properties of poly(butylene isophthalate) and its copolyesters with poly(butylene adipate)

✍ Scribed by Maria Cristina Righetti; Maria Pizzoli; Andrea Munari

• Publisher: John Wiley and Sons
• Year: 1994
• Tongue: English
• Weight: 403 KB
• Volume: 195
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.1994.021950613

✦ Synopsis

Abstract

The thermal properties of uniformly random poly(butylene adipate/isophthalate) copolyesters of various composition and different molecular weight were investigated by means of differential scanning calorimetry. All copolymers were partially crystalline, and the main effect of copolymerization was a lowering in the amount of crystallinity and a decrease of melting temperature with respect to pure homopolymers. The heat of fusion of 100% crystalline poly(butylene isophthalate), estimated by different methods, was found to fall within the range 22–25 kJ · mol^−1^. Completely amorphous samples, obtained by rapid quenching from the melt, showed a monotonic decrease of the glass transition temperature T~g~ and a monotonic increase of the heat capacity increment Δ__C__~p~ with increasing butylene adipate content in the copolymers. The T~g~‐composition dependence was found to be well fitted by the Couchman equation with no excess enthalpy correction.