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This paper aims to investigate the optimal formulation of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx)/ZnO bionanocomposites for food packaging applications with respect to filler content ratio. Bionanocomposite samples prepared by melt-compounding at various ZnO-NPs contents (1.5, 3, and 6 wt%) were evaluated in terms of optical, thermal, viscoelastic, and mechanical properties. UV–Vis spectroscopy revealed a significant enhancement in the photochemical stability of PHBHHx/ZnO bionanocomposites compared with neat PHBHHx, which exhibits a strong absorption band at wavelengths below 380 nm, thus confirming the anti-UV activity of ZnO nanoparticles. Thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA) demonstrated improved thermal stability and increased stiffness/mechanical strength with increasing ZnO-NPs content. Notably, the bionanocomposite with 3 wt% of ZnO exhibited the most substantial improvements, with a 20% increase in thermal decomposition temperature and a 30% increase in storage's modulus at room temperature than the neat PHBHHx. Moreover, a decrease in loss modulus (E″) and tanδ indicated reduced energy dissipation and enhanced material elasticity. Overall, incorporating 3 wt% ZnO nanoparticles into PHBHHx resulted in a bionanocomposite with superior photochemical stability, thermal stability, and viscoelastic properties compared to both neat PHBHHx and other bionanocomposite samples, which makes it as a promising candidate for food packaging applications. [ABSTRACT FROM AUTHOR]

The development of new bio‐based and biodegradable composites with enhanced performances is an efficient route to achieve a sustainable materials production. In this work, biocomposites materials based on PHBHHx reinforced with Agave leaves fibers (ALF) are elaborated by melt compounding at various filler content ratios, i.e., 10, 20, and 30 wt%. Thermal stability, tensile, and surface properties are investigated aiming to evaluate the effect of the ALF content on the material properties. The results show that the addition of ALF leads to reinforcement effect on PHBHHx, which is more pronounced at 30 wt%. Conversely, thermal stability of the biocomposites slightly decreases compared with the neat polymer, while the surface properties are almost unchanged whatever the filler content. [ABSTRACT FROM AUTHOR]

Hygrothermal aging of neat poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) (PHBV) and PHBV filled with an organomodified montmorillonite (C30B) at 3wt. was investigated at 65°C and 100% relative humidity (RH) up to 100 days. FT‐IR data indicated that the carbonyl intensity index decreased with exposure time for both samples, while the main degradation mechanism occurred through hydrolysis reaction. This led to chain scissions resulting in a decrease in molar mass. Water absorption increased with exposure time for both neat PHBV and PHBV/C30B (3wt%) bionanocomposite. Differential scanning calorimetry measurements showed a decrease in both crystallinity index and melting temperature after hygrothermal aging and thermogravimetric analysis data indicated also a decrease in thermal stability. Mechanical and viscoelastic properties were also altered, being, however, more pronounced for the neat PHBV. Overall, the PHBV bionanocomposite exhibited a better resistance toward hygrothermal aging at 65°C and 100% RH. [ABSTRACT FROM AUTHOR]

The article reports some experimental data on the effects of three types of clay: organo-modified montmorillonite (cloisite 30B (C30B)), sepiolite (SP9), and halloysite nanotubes (HNT) on the morphology and physicomechanical properties of polycaprolactone (PCL)/clays bionanocomposites prepared by melt compounding. The clays were incorporated separately into the PCL matrix at a loading rate of 5.00 wt%, which corresponds to 2.91 ± 0.53, 2.42 ± 0.02, and 2.68 ± 0.13 vol% for C30B, SP9, and HNT, respectively. Scanning electron microscopy analysis showed good dispersion of both C30B and SP9 in the polymer matrix, while the presence of a few HNT aggregates was observed on the fracture surface of the PCL bionanocomposite. Furthermore, the HNT aggregates were randomly dispersed. The results indicated an enhancement of the rheological and tensile properties of the PCL bionanocomposite samples filled with C30B and SP9 compared to those containing HNT. Indeed, it was shown an increase in Young's modulus of PCL from 450 ± 16 MPa to 563 ± 42 MPa, 645 ± 68 MPa, and 502 ± 66 MPa for PCL bionanocomposites loaded with C30B, SP9, and HNT, respectively. On the other hand, the thermal stability of the whole PCL bionanocomposite samples was reduced being, however, more pronounced for those containing HNT. The decomposition temperature recorded at 5.00 wt% loss (T 5%) indicated 384.7 ± 0.9 for neat PCL, while the PCL bionanocomposites filled with C30B, SP9, and HNT exhibited the values of 357.3 ± 0.5, 353.2 ± 0.9, and 368.4 ± 0.4, respectively. [ABSTRACT FROM AUTHOR]

In this study, biocomposites of poly(3‐hydroxybutyrate‐co‐3‐hydroxyhexanoate) (PHBHHx)/cellulose microcrystalline (MCC) extracted from olive husk flour are prepared by melt compounding at various filler content ratios, i.e., 10, 20, and 30 wt%. The effect of the MCC content on the morphology, thermal stability, crystallinity, and water uptake of the PHBHHx biocomposites is investigated. The results showed that the addition of MCC to PHBHHx decreased the thermal stability of the biocomposites compared to that of neat polymer, however more pronounced at a higher filler content. This is due probably to the tendency of MCC particles to agglomerate, inducing heterogeneities and defects within the polymer matrix observed by scanning electron microscopy. Furthermore, both crystallinity and water uptake after 24 h of immersion increased with the filler content. [ABSTRACT FROM AUTHOR]

Abstract: In this study, multifilament fibers based on neat poly(lactic acid) (PLA), PLA/cellulose nanowhiskers (CNWs), and PLA/cellulose microcrystalline (MCC) loaded at 1 and 3 wt.% were prepared by melt‐spinning process in the presence of PLA‐grafted maleic anhydride (PLA‐g‐MA) used as the compatibilizer and PEG as the plasticizer. This study showed that the incorporation of MCC in PLA matrix whatever the loading rate was not suitable for multifilament fibers spinning compared with CNW, due to the restricted drawability and a poor dispersion of the MCC within the PLA matrix. Furthermore, the whole characterization studies indicated that the incorporation of 1 wt.% of CNW in PLA with addition of the compatibilizer led to better thermal stability, flame retardancy, and multifilament tensile properties compared with neat PLA and with other filled PLA multifilament fibers. [ABSTRACT FROM AUTHOR]

The paper deals with the influence of surface treatment of olive husk flour (OHF) by trimethoxyoctadecylsilane (TMOS) on the morphology and physical properties of bio-composites based on poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). Biocomposites based on PHBV/OHF: 80/20 (w/w) before and after filler treatment were prepared by melt compounding, while the modification of OHF surface by TMOS was performed by thermo-chemical vapor deposition. Scanning electron microscopic observations showed that modification of OHF by TMOS led to homogeneous and finer dispersion of the filler particles in PHBV matrix, indicating improved compatibility between the two components. Further, TGA data revealed an increase in thermal stability of treated PHBV/OHF biocomposites. An increase in the crystalline index determined by DSC was also observed due to the nucleating effect of OHF in the polymer matrix, however more pronounced for the treated biocomposites. The latter exhibited better tensile properties, as confirmed by DMA results, showing higher reinforcing effect of OHF for the treated biocomposites. This study highlighted significant improvements of the properties of PHBV/OHF biocomposites through silane treatment of OHF. [ABSTRACT FROM AUTHOR]

Blends of poly(3-hydroxybutyrate- co-3-hydroxyvalerate) (PHBV) and polylactide (PLA) with different PHBV/PLA weight ratios (100/0, 75/25, 50/50, 25/75, 0/100) were prepared by melt compounding. Their mutual contributions in terms of thermal stability, flammability resistance, mechanical properties and rheological behavior were investigated. The study showed that the increase in PLA content in PHBV/PLA blends leads to enhanced properties. Consequently, thermal stability and flammability resistance were improved. Further, the rheological measurements indicated an increase in storage modulus and loss modulus of PHBV matrix by addition of PLA. [ABSTRACT FROM AUTHOR]

The olive pomace was modified chemically to improve the interface between the polymer matrix and the cellulosic fillers. The modification was done using various ester types having the same nature, however, with different chain lengths and one silane. Before the surface treatment, the olive pomace was extracted with acetone to remove contaminants on the surface, using Soxhlet apparatus. The transesterification of olive pomace with the different ester components, i.e., vinyl acetate, vinyl propanoate, and vinyl butanoate, and the condensation reaction with dichlorodimethylsilane was confirmed by Fourier transform infrared (FTIR) analysis. Moreover, the treatment of olive pomace with vinyl acetate improves the thermal stability and the sample records higher onset temperature of degradation as measured by thermogravimetric analysis (TGA). The results obtained indicated also that the reaction between the hydroxyl groups of waste flour and the acetyl, propionyl, pivalyl, and silane groups have occurred. The modified wood flours exhibited a decrease in the hydrophilicity as supported by the lower moisture content. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [ABSTRACT FROM AUTHOR]

In recent years, there has been a great interest in biodegradable polymer composites. Besides polylactides, polyhydroxyalcanoates (PHA) are the most commonly used as matrices due to their biodegradability, biocompatibility and good properties compared with synthetic polymers. Despite many advantages, bio-fillers still have limited applications as reinforcement due to a lack of adhesion to polymers and their inherent high moisture absorption. Therefore, achieving a good adhesion between bio-fillers and the polymer represents one of the major challenges in composite materials. Therefore, the objective of this paper was to investigate the effect of PHBV grafted maleic anhydride (PHBV-g-MA) compatibilizer used at 5 wt. %, on the morphology and properties of PHBV/OHF biocomposites at various filler contents, i.e., 10, 20 and 30 wt.%. The study showed that PHBV-g-MA improved filler dispersion in the matrix and promoted the interactions between PHBV and OHF resulting in improved thermal stability and tensile and barrier properties compared to the non-compatibilized biocomposites. [ABSTRACT FROM AUTHOR]