Shear and Extensional Rheology of Linear and Branched Polybutylene Succinate Blends

The molecular architecture and rheological behavior of linear and branched polybutylene succinate blends have been investigated using size-exclusion chromatography, small-amplitude oscillatory shear and extensional rheometry, in view of their processing using cast and blown extrusion. Dynamic viscoelastic properties indicate that a higher branched polybutylene succinate amount in the blend increases the relaxation time due to an increased long-chain branching degree. Branched polybutylene succinate exhibits pronounced strain hardening under uniaxial elongation, which is known to improve processability. Under extensional flow, the 50/50 wt % blend exhibits the same behavior as linear polybutylene succinate.

Automated summary

The rheological behavior of linear and branched polybutylene succinate blends were investigated under different processing conditions, revealing that a higher level of branching in the blend leads to increased relaxation time and improved strain hardening during uniaxial elongation. The 50/50 wt% blend exhibited similar behavior to linear polybutylene succinate under extensional flow, indicating potential benefits for processing.