ZnO nanoparticles as chain elasticity reducer and structural elasticity enhancer: Correlating the degradating role and localization of ZnO with the morphological and mechanical properties of PLA/PP/ZnO nanocomposite

Abstract

The main purpose of this study was to investigate the effect of zinc oxide (ZnO) nanoparticles on the morphological, mechanical, thermal, and rheological properties of PLA/PP blend. In this regard, nanocomposites containing 1, 3, and 5 wt% of ZnO nanoparticles were prepared by melt mixing. In addition, three different mixing procedures were adopted to study their effects on the microstructure of nanocomposites. The rheological behaviors demonstrated a higher elasticity and less compatibility for two phases in the case of nanocomposites containing nanoparticles in harmony with the morphological observations. Accordingly, it was correlated to the elasticity originating from the interphase, anticipated coalescence of dispersed particles as a result of degradation of PLA chains triggered by ZnO nanoparticles (ZnO‐NPs) and also agglomeration of ZnO‐NPs depending on the content of nanoparticles and chosen mixing procedure. It was also found that mixing method puts a remarkable influence on the microstructure and rheological behavior of nanocomposites. Results of mechanical characterizations and thermogravimetric analysis (TGA) also confirmed the degradation induced by ZnO nanoparticles.

Synergistic toughening of poly(lactic acid)/poly(ethylene vinyl acetate) (PLA/EVA) by dynamic vulcanization and presence of hydrophobic nanoparticles

“…During compounding the components, the thermodynamics tries to decrease the free energy of the system by localizing the NPs at the desirable phases (PLA, EVA, or their interface). At the equilibrium, the preferential localization of nanoparticles can be predicted from a thermodynamic point of view by calculating the wetting parameter (), according to Young's equation 41–43 : where represents the interfacial tension between the silica particles and polymer; and is the interfacial tension between the two polymers. If , NPs tend to locate in EVA polymer; For NPs prefer to be localized into the PLA phase, while indicates the thermodynamically preferred localization of NPs at the interface.…”

Preparation and study on the optical, mechanical, and antibacterial properties of polylactic acid/ZnO/TiO2 shared nanocomposites

“…8,10,11 Various researchers have used different strategies to improve the mentioned properties such as manufacturing PLA nanocomposites using mineral or natural fillers, depending on the special applications. 8,[12][13][14][15] As a result, metal oxide nanoparticles have shown a great potential to improve the mechanical properties, UV-shielding, and non-permeability. In this regard, zinc oxide (ZnO) and titanium oxide (TiO 2 ) semiconductor nanoparticles are among the most suitable fillers to enhance PLA performance.…”

“…16,19 ZnO is also a non-toxic and multi-functional mineral nanoparticle with high chemical stability, high catalytic activity, considerable ultraviolet light absorption, and antibacterial properties which is recognized as a safe material by the US Food and Drug Administration. 6,[13][14][15][16][17][20][21][22] Searching the literature, numerous publications are available regarding the PLA/ZnO and PLA/TiO 2 nanocomposites and their property improvements in terms of dispersion state, 23 mechanical, [17][18][19] thermal, 10,24,25 optical, 10,26 and antibacterial 16,27 properties. For instance, Therias et al 28 investigated how light affects PLA/ZnO nanocomposite films prepared by melt extrusion.…”

Preparation and properties of enhanced nanocomposites based on PLA/PC blends reinforced with silica nanoparticles

“…It is employed in many applications including electrical equipment, automotive parts, durable consumer goods, and especially in the packaging industry because of its availability and compostability. The main drawbacks of PLA that limits its applications are: low thermal stability, annealing behavior after moulding, brittleness, high hydrolytic susceptibility, relatively low glass transition temperature (T g ), cold crystallization behavior, and low crystallization rate as compared with the traditional petroleum-based plastics.. [1][2][3][4][5][6] To compensate these defects, incorporation of additives such as inorganic nanoparticles or blending with tough polymers like polycarbonate bisphenol A (PC), polyamides (PAs), etc, are considered. Nanoparticles or nanofillers can enhance its low crystallization rate and consequently modify annealing and cold crystallization behaviors.…”