Influence of different molecular weights of polyhexene‐1 on the morphology and rheology of cyclic olefin copolymer blends

Abstract

The morphology and rheological behavior of cyclic olefin copolymer (COC) blends with two molecular weights of polyhexene-1 (PH-1, PH-1-UH [ultrahigh]) were investigated at a wide range of compositions. Morphology of the blends at low concentrations of polyhexene-1 s showed a droplet-matrix structure and changed to a co-continuous morphology at intermediate concentrations. The rheological Cole-Cole plots and viscosity versus composition confirmed immiscibility of the blends. The interfacial interaction of blends phases was investigated and Complex viscosity and storage modulus versus frequency were measured and the results were consistent with high interfacial strength between the COC and high concentrations of PH-1-UH which increases the melt strength of the blends. Relaxation time spectra and Tan δ versus frequency curves were analyzed and these results were consistent with a high degree of entanglements between the COC and PH-1-UH chains in the PH-1-UH-rich compounds which in turn increased the elasticity. Damping factor measurements and calculation of interfacial tension using emulsion models showed that in the COC-rich blends, the interfacial interaction COC/PH-1 blends is higher than that of the COC/PH-1-UH blends and thus the elasticity and particles form relaxation time of the PH-1 blends are higher compared to PH-1-UH blends.

Modified ethylene/α‐octene co‐polymer elastomer composites with sacrificial bonds crosslinking networks and their reinforced mechanical performance

“…[ 28,55 ] Besides, the complex viscosity of the samples decreased with the increase of angular frequency, showing shear thinning characteristics, which was conducive to the processing of elastomer. [ 56 ] As shown in Figure 5D, PMAFe0.1–30% had the highest G ′, followed by PMAFe0–30%, and POE was the lowest. Due to the introduction of dynamic crosslinking network, the storage modulus of modified elastomer increased and the melt elasticity became higher.…”