Abstract: ADR series chain extenders wers used for spinning poly (3-hydroxybutyrate-co-4-hydroxybutyrate) (P(3HB-co-4HB)).The rheology, thermal stability, crystallinity and fiber mechanical properties of P (3HB-co-4HB) and P (3HB-co-4HB)/ADR blends were investigated, along with the chain extendsion mechasim of ADR. The results showed that ADR can increase the melt strength, and improve the thermal stability of the fibers; and when the addition amount of ADR is 0.5% at 155°C, the melt has the maximum shearing strength and tensile strength, as well as optimum heat resistance. The influence of ADR on the crystal structure of P (3HB-co-4HB) is not remarkable, but it leads to the reduction of the crystallization rate and the increase of the maximum crystallization temperature. The mechanical properties of P (3HB-co-4HB) fibeers are significantly improved with ADR added.

Key words: poly (3-hydroxybutyrate-co-4-hydroxybutyrate), rheology, thermal stability, crystallinity, mechanical property