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This study introduces an innovative utilizing polybutylene succinate (PBS) and polyvinyl alcohol (PVA) for seedling bags, enriched with glycerol (G) and calcium hydrogen phosphate (CaHPO4) fertilizer. The investigation examined the impact of PVA (10–50 wt.%) with fixed glycerol ratio of 20 phr, and CaHPO4 content (0–7 phr) on the composite. Notably, higher PVA content led to better dispersion of PVA particles within the PBS/G blend, reducing phase separation compared to lower PVA content. However, increased PVA content resulted in decreased mechanical properties due to incompatibility and phase separation, as well as interference with PBS crystallization. Regarding CaHPO4, the addition of a low fertilizer amount (3 phr) slightly reduced crystallinity (from 40% to 19%) but increased elongation at break (from 2.7% to 3.8%). Conversely, higher CaHPO4 content (5–7 phr) significantly enhanced tensile strength and elongation at break to 5.6 MPa and 6.3%, respectively, without affecting crystallinity. Importantly, CaHPO4 incorporation improved the dispersion of PVA within the PBS matrix. In practical application, PBS/PVA/G/CaHPO4 composites proved suitable for planting seedlings, which thrived in the bags over 42 days. This study underscores the potential of these composite materials for seedling cultivation, while future research may delve into optimizing fertilizer effectiveness in this context. [ABSTRACT FROM AUTHOR]

This study investigates the crystallization, microstructure, and performance of poly(lactic acid)/poly(butylene succinate) (PLA/PBS) thin films processed through blown film extrusion and biaxial orientation (BO) at various blend ratios. Succinic anhydride (SA) was used to enhance interfacial adhesion in PLA-rich blends, while blends near 50/50 formed co-continuous phases without SA. Biaxial stretching and annealing, adjusted according to the crystallization behavior of PLA and PBS, significantly influenced crystallinity, crystallite size, and molecular orientation. Biaxial stretching induced crystallization and ordered chain alignment, particularly at the cold crystallization temperature (Tcc), leading to a 70–80-fold increase in impact resistance compared to blown films. Annealing further enhanced crystallinity, especially at the Tcc of PLA, resulting in larger crystallite sizes. BO films demonstrated reduced thermal shrinkage due to improved PLA crystalline structure, whereas PLA-rich blown films showed higher shrinkage due to PLA's lower thermal resistance. The SA-miscibilized phase reduced oxygen transmission in blown films, while BO films exhibited higher permeability due to anisotropic crystal orientation. However, the annealing of BO films, especially at high temperature (Tcc of PLA), further lowered oxygen permeability by promoting the crystallization of both PLA and PBS phases. Overall, the combination of SA compatibilization, biaxial stretching, and annealing resulted in substantial improvements in mechanical strength, dimensional stability, and oxygen barrier properties, highlighting the potential of these films for packaging applications. [ABSTRACT FROM AUTHOR]

This research was focused on the properties of poly (vinyl alcohol) (PVOH) blended with pregelatinized starch (PSt) as a suitable material to make laundry bags for infected clothes application. PVOH and PSt (0, 10, 20, 30, and 40 wt.%) with glycerol 20 phr were melt-blended by twin-screw extruders. The samples were processed into the film by single layer-blown film extrusion. From the results, it was found that PVOH, glycerol, and pregelatinized starch had intermolecular interactions with each other, forming hydrogen bonding interactions between PVOH/pregelatinized starch and glycerol. The glass transition temperature (Tg) of a blend was shifted to a higher temperature by increasing the pregelatinized starch content leading to a reduction in the percent crystallinity. The presence of pregelatinized starch slightly increased the melt flow rate (MFI)/melt volume rate (MVR), apparent viscosity, and viscosity average molecular weight (Mv) of the blends due to the chain entanglement but it decreased the water solubility time and the moisture content. A co-continuous phase with small coalescence was found when 30% pregelatinized starch was added, increasing the elongation at break to 171%. On the other hand, the pregelatinized starch content was 40%, the elongation at break reduced to 154%. [ABSTRACT FROM AUTHOR]

Composites of a biodegradable thermoplastic aliphatic polyester, polybutylene succinate (PBS), with bentonite were investigated for morphological and mechanical properties. The bentonite was modified with soybean oil (SBO) and lard oil (LO) (2:98 clay:oil % by weight) by mechanical stirring and ultrasonication. The PBS/modified bentonite composite was prepared by using an internal mixer and processed by compression molding. Under bentonite modification conditions, XRD and SEM showed that the bentonite layers were broken into small layers, and the d-spacing between the layers was increased by edible oil molecules. A small plate like structure of modified bentonite composite was observed by SEM micrograph, which revealed short and long layer silicate structure non-directionally throughout the matrix phase. The mechanical properties of PBS were reinforced by this structure. The tensile modulus and elongation at break seem to depend on its directional bentonite. Interestingly, considerable improvement in impact strength was observed at over 2 wt% of clay. The impact strengths of PBS, PBS/modified BTN with SBO composite, and PBS/modified BTN with LO composite were increased from 1 to 1.5 and 2 kJ/m2, respectively. Comparatively, using LO modified bentonite had a better performance for increased interlayer and resulted in higher impact strength of the composite than that of SBO composite. The results demonstrated that PBS/modified bentonite using edible oil could be a potential alternative low cost, eco-friendly material with superior impact properties useful for further applications. [ABSTRACT FROM AUTHOR]

This study investigated the effect of polylactic acid (PLA)/poly‐d‐lactide (PDLA) stereocomplex (ST) on the improvement of the mechanical and thermal properties of various rubber‐toughened PLAs. In this work, natural rubber (NR), synthetic polyisoprene rubber (IR), silicone rubber (SI), acrylic rubber (ACM), acrylic core–shell rubber (CSR), thermoplastic copolyester (TPE) and thermoplastic polyurethane (TPU) were chosen as the toughening agents. 5 wt% PDLA was melt‐blended with PLA to form ST crystals in the presence of 15 wt% rubber in an internal mixer at 180 °C and 50 rpm. It was found that the melting temperature of ST crystal (Tm,sc) and the impact strength of ST/rubber blends were strongly correlated with the rubber domain size. For the blends of ST with compatible rubbers (ACM, CSR, TPE and TPU), the rubber domain sizes tended to be smaller with higher Tm,sc and higher impact strength than the blends with incompatible rubbers (NR, IR and SI). However, the presence of ST crystals in PLA/incompatible rubber blends, especially the blends with NR and IR, led to a significant increase in the rubber domain size and plunges in tensile toughness and impact strength. On the other hand, the presence of these crystals in PLA/compatible blends did not change the rubber size or the impact strength significantly compared with those without ST crystals except in the case of ST/ACM, which resulted in a large increase in the impact strength. Among all rubber types, CSR provided the highest impact strength for both the PLA and ST systems. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]