Electrical and mechanical properties of partially bio‐based PP/PBS blends nanocomposites elaborated by twin‐screw extrusion

Abstract

Organically modified montmorillonite (OMMT, Cloisite 20) was used as reinforcing filler to prepare nanocomposites from a blend of polypropylene (PP) and eco-friendly degradable polybutylene succinate (PBS). A PP grafted with maleic anhydride was also added as a compatibilizer. Scanning electron microscopy observations indicated that the blend morphology was affected by the presence of OMMT, which acted as a compatibilizer between PP and PBS.Rheological measurements showed a significant increase of the complex viscosity when OMMT was added above a certain amount. X-ray diffraction indicated an intercalated structure for all nanocomposites. The addition of OMMT improved mechanical properties of neat matrices and blends. The electrical insulation properties were preserved for low concentrations of OMMT, up to 2 wt%. Then, to guarantee good mechanical properties without deteriorating electrical ones, while maintaining a sufficient bio-based composition, the 70/30 (PP/PBS) blend with clay concentrations of less than 2 wt% appeared to be the most satisfactory nanocomposite for applications in the field of electrical insulation.

Enhancing crystallization, miscibility, and processability of bio‐based polybutylene succinate/polypropylene blended composites via coffee husk reinforcement

“…Figure 9A shows that the viscosities of the blends and composites decrease with increasing shear rates, indicating shear thinning and non‐Newtonian behaviors. Previous works have clearly suggested that there are large differences in the viscosities between neat PP and PBS, with the viscosity of PP being more than 1000 times that of neat PBS 28 . Hence, the non‐compatibilized blend (50PP/PBS) has the lowest viscosity and shows no dependence on changes in the angular frequency.…”

“…It is also reported that the peaks at 2 θ = 14.1°, 16.8°, 18.5° are related to the (110), (040), and (130) crystal planes of the α‐phase crystal of PP while there is a small peak attributed to the (300) crystal plane of β‐phase crystal plane of PP at 16.1°. On the other hand, PBS has α‐phase monoclinic crystals represented by crystal planes (020), (021), (110), and (111) at 2 θ = 19.6°, 21.9°, 22.6°, and 28.7° 28,44 . The results indicated that the position of XRD peaks of each polymer did not change, regardless of the PP loading content or addition of compatibilizer.…”

“…Previous works have clearly suggested that there are large differences in the viscosities between neat PP and PBS, with the viscosity of PP being more than 1000 times that of neat PBS. 28 Hence, the non-compatibilized blend (50PP/PBS) has the lowest viscosity and shows no dependence on changes in the angular frequency. The viscosities of the 50M-PP blend and the reinforced composites show dependences at lower frequencies, with 50PP-mCH exhibiting a dramatic increase in viscosity.…”

“…The utility of PBS in advanced end‐use applications is limited owing to its low melt viscosity, low melt stability, slow crystallization, and high cost 25–27 . Miscible PP/PBS blends have been fabricated by incorporating a relatively high content of PP grafted with a maleic anhydride (PP‐g‐MA) compatibilizer to further improve the melt viscosity of the blend 28 . Kim et al 29 fabricated compatibilized PP/PBS composites filled with natural flour to improve their miscibility and viscoelastic behaviors.…”

“…[25][26][27] Miscible PP/PBS blends have been fabricated by incorporating a relatively high content of PP grafted with a maleic anhydride (PP-g-MA) compatibilizer to further improve the melt viscosity of the blend. 28 Kim et al 29 Similarly, cellulose-based biofillers from several plant and forestry wastes have been used as low-cost reinforcement for improving the properties of various composites. Owing to the extensive global consumption of coffee, the use of coffee wastes as a bio-filler is rapidly gaining interest.…”