Abstract:

Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and Poly (lactic acid) (PLA) blends for melt-blown nonwovens were prepared with different ratios (100/0,75/25,50/50,25/75,0/100) by melt mixing. The thermal properties, melt flowing index, crystallization and rheological behavior of PHBV/PLA blends were investigated, and its as-spun fiber was also prepared to evaluate the spinnability of blends. The results showed that pure PHBV had poor thermal stability, narrow processing window and low melt flow rate, blended with PLA improved the thermal stability and melt fluidity of PHBV; pure PHBV also had fast crystallization rate with nucleating agent and PLA had a dilution effect on the crysyalizaion of PHBV; PHBV had high sensitivity to the temperature and shear rate changes, PHBV/PLA blends had mixing characteristic of shear thinned liquid and the apparent viscosity of blends increased with the increasing of PLA but was less than pure PLA; PHBV had poor spinnability with serious sticky situation and low drawing ratio of as-spun fiber, but it could be improved with the blending of PLA and the surface also became more smoother.

Key words: poly(3-hydroxybutyrate-co-3-hydroxyvalerate), poly(lactic acid), spinnability, melt-blown