No abstract

Poly(lactic acid) (PLA) and NPK fertilizer with empty fruit bunch (EFB) fibers were blends to produced bioplastic fertlizer (BpF) composites for slow release fertilizer. Thermal properties of BpF composites were investigated by thermogavimteric analysis (TGA), differential scanning calorimetry (DSC), and morphological and degradation properties were anlayzed by scanning electron microscopy (SEM), soil burial test, respectively. TGA themogram display that neat PLA, PLA/NPK, and BpF composites degradate at different temperatures. DSC curves of PLA and other composites exhibited same glass transition temperature (Tg) value indicating that both major blend components are miscible. The Tg, crystallization temperature (Tc), melting temperature (Tm) values also decreased with increased amount of fertilizer and fibers. The Tm of BpF composites did not change with an increase in fertilizer content because thermal stability of PLA and PLA/NPK composites was not affected. Soil burial and fungal degradation test of PLA, PLA/NPK, and BpF composites were also carried out. Soil burial studies indicated that BpF composites display better biodegradation as compared with neat NPK. Fungal degradation study indicated that fungi exposure times of BpF composites show higher value of degradation as compared with PLA/NPK. We attribute that developed BpF composites will help oil palm plantation industry to use it as slow release fertilizer. POLYM. COMPOS. 36:576–583, 2015. © 2014 Society of Plastics Engineers

Graphene nanoplatelets (xGnP) were investigated as a novel nanoreinforcement filler in poly (lactic acid)(PLA)/poly (ethylene glycol)(PEG) blends by melt blending method. The prepared nanocomposites exhibited a significant improvement in tensile properties at a low xGnP loading. The tensile properties demonstrated the addition of 0.3wt% of xGnP led to an increase of up to 32.7%, 69.5% and 21.9% in tensile strength, tensile modulus and elongation at break of the nanocomposites respectively, compared to PLA/PEG blend. The nanocomposites also shows enhanced thermal stability compared with PLA/PEG blend in thermogravimetry analysis (TGA). Scanning electron microscopy (SEM) image of PLA/PEG/0.3wt% xGnP displays good uniformity and more homogenous morphology.

Slow-release bioplastic fertilizer (BpF) composites were developed by processing oil palm empty fruit bunch (EFB), fertilizer, and poly(hydroxybutyrate-co-valerate) (PHBv) using extrusion techniques with controlled formulation and temperature. The temperature was kept at 150°C for 3 to 5 min during processing using twin-screw extruder. The PHBv lost weight gradually with the increasing temperature and its thermal degradation occurred initially at 263.4°C and reached the maximum at 300.7°C. Scanning electron microscope (SEM) images showed that the bonding of all composites created small gaps between matrices polymer and fiber because the hydrophilic characteristic of EFB fibers weakened the interfacial bonding. PHBv/EFB/NPKC2 showed faster biodegradation over PHBv/NPKC1 and PHBv/NPKC2, which was 99.35% compared to 68.66% and 90.28%, respectively.

The objective of this work was to evaluate the adhesion and basic properties of kenaf stem, and its physical and mechanical properties on particleboard panels. In this study, rubberwood (RW) was used as a control. Single-layer experimental panels were produced from whole stem, core, and bast particles of kenaf. Findings revealed that the core part resulted in higher wettability and lower contact angle than the bast. Kenaf bast (KB) gave the highest buffering capacity, while kenaf core (KC) gave the lowest buffering capacity towards acid. The lowest specific gravity was shown by KC followed by kenaf whole stem (KWS) and KB. For particle analysis, KWS gave the highest acceptable particle distribution (73.9%), whilst KC, KB, and RW had particle distributions of 62.5, 68.1, and 56.8%, respectively. Particleboard panels produced from KWS had the highest average values of modulus of rupture and modulus of elasticity with good compaction under scanning electron microscopic. Panels made from bast particles had the lowest mechanical properties among the three types of panels. The internal bonding strengths and dimensional stability of the specimens followed the similar trend above. The results of this study indicate that the specific gravity and adhesion properties of the starting material play a role in determining the physical and mechanical properties of the particleboard panels.