Study on the Torque Rheological Behavior of Wood Flour/Chitosan/Polyvinyl Chloride Composites

Abstract

Torque rheological properties of wood flour/chitosan/PVC (WF/CS/PVC) compounds were measured by a torque rheometer using roller-style rotating blades at various setting temperatures (175 and 185 °C) and rotation speeds (30, 45, 60, and 75 rpm). The torque rheological parameters were calculated based on the Marquez model and Arrhenius equation. The torque rheological curves of WF/CS/PVC composites were similar to WF/PVC composites without chitosan. The classical Marquez model was verified to be suitable for both WF/PVC and WF/CS/PVC composites. Specifically, the activation energy (ΔE), n value, and range of C(n)m for the former and latter were 27.698 kJ·mol -1 and 29.237 kJ·mol -1 , 0.382 and 0.381, and 4.415 to 5.749 N·m·s n and 4.652 to 6.079 N·m·s n , respectively. The rheological properties of WF/CS/PVC composites did not show a great qualitative enhancement compared to WF/PVC composites.

Influence of filler loading and palm oil‐based green coupling agent on torque rheological properties of polypropylene/cocoa pod husk composites

“…This suggests that the composite compound experienced a lower shear thinning with addition of GCA‐P. A number of researchers conducted torque rheological studies on thermoplastic composites with different natural filler also have the similar observation …”

“…As highlighted in preceding section, the viscosity of composite compound increased at higher filler loading. [22,33,34] Figure 6 shows the viscosity of neat PP and all PP/CPH composites at different shear rate. [32] For composite formulation with addition of GCA-P, higher shear stress of the composite compounds was recorded.…”

“…Therefore, a higher shear stress was required to induce more viscous flow in composite T A B L E 2 Processing parameter for torque rheological analysis Figure 4, the slope of log shear stress versus log shear rate plot gives the power law index (n) of the non-Newtonian melt flow. [22] The E a can be calculated from the plot of log viscosity versus log reciprocal of absolute temperature through curve fitting method. The powder index n for both composite compounds with and without GCA-P reduces as the CPH loading increases.…”

“…This showed that the pseudoplasticity of both composites increased, and it undergoes shear thinning at higher CPH loading. Xu et al [22] reported that the E a of polyvinyl chloride (PVC) composites containing wood four increased after addition of coupling agent. This suggests that the composite compound experienced a lower shear thinning with addition of GCA-P. A number of researchers conducted torque rheological studies on thermoplastic composites with different natural filler also have the similar observation.…”

“…The compounding process of thermoplastic composites is more challenging than normal thermoplastic compound, especially in thermoplastic composites containing very high filler loading . In this regard, the rheological behavior of the thermoplastic matrix is also an important parameter, as it will influence the compound quality and properties of composites . It has been reported from open literature that the main factors influencing the rheological properties of thermoplastic composites are filler loading, type of filler, and interfacial adhesion .…”