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The influences of annealing temperatures on the electrical characteristics of a p-NiO/n-TiO2 heterojunction diode were thoroughly investigated, taking into account changes in microstructure, morphology, and surface chemistry of the p-NiO/n-TiO2 films, which were deposited on an insulating SiO2/Si layer. During different annealing processes, considerable stress variations were observed in the p-NiO/n-TiO2 films due to the crystalline evolution of p-NiO and n-TiO2. Notably, the crystallization of the TiO2 layer, which serves as the intermediary between the back contact materials and NiO, led to the evident formation of grain structures. As the annealing temperature increased, the surface roughness also grew from 5.4 to 8.7 nm. At an annealing temperature of 500 °C, the formation of a parasitic NiTiOx phase was observed, particularly at the interface between NiO and TiO2. Conversely, the study also revealed that annealing temperature played a significant role in the rectifying behavior, barrier potential, and ideality factor of the diode. Among the various annealing processes, the most favorable results were achieved after annealing at 400 °C. At this temperature, the diode demonstrated the lowest ideality factor of 1.89, accompanied by superior rectifying behavior and a barrier potential of 0.70 eV. The findings clearly indicate that any alterations in the surface chemistry and microstructure of the film directly impact the diode's characteristics. Thus, optimizing the annealing temperature becomes crucial for enhancing the performance of the p-NiO/n-TiO2 heterojunction diode. [ABSTRACT FROM AUTHOR]

This study mainly aims both to prepare well-shaped crosslinked 3,3,4,4,5,5,6,6,7,7,8,8,8 tridecafluorooctyl-4-(acrloyloxy) benzoate (ABCF13) polymer microspheres and to investigate the influences of the prepared microspheres addition on the crystallinity, thermal, mechanical and morphological features of high density polyethylene (HDPE). The suspension polymerization method was used for the production of well-defined microspheres and, the content of the microspheres varied from 1.0% to 10.0% in the composites. The characterization of crosslinked poly(ABCF13) microsphere-loaded HDPE composites were performed via powder X-ray diffraction, differential scanning calorimeter, universal mechanical (tensile and impact) testers and scanning electron microscope (SEM) techniques. According to the experimental findings, a and b unit cell parameters increased initially and reached maxima with the sample including 5.0% microsphere, which were followed by dramatic decreases, while c parameter remained relatively unchanged. Thermal analysis also showed that the melting temperature of HDPE reduced with the initial loading of the microspheres, then stayed at a plateau value of about 129°C due to the formation of lattice distortions, generation of microstructural disorders and the defects in the crystal structures. The mechanical test results revealed that there existed considerable improvements in tensile strength, modulus and impact strength. The maximum tensile strength 25.66 MPa, elastic modulus 499.30 MPa and maximum absorbed energy in the impact test 26.84 kJ/m2 (29%, 42% and 41% improvement, respectively) were achieved with the blend involving 5.0% microsphere. After the maxima, the mechanical characters depicted weakening trend as the microsphere content increased in the matrix. The SEM analyses revealed that although there existed fibrillar formations in all samples, the extensions decreased with the increase of the microsphere content. While ductile behavior was observed with the formation of long-bulky extensions at low contents, brittleness started to prevail at high contents with some short and thin fibrils. [ABSTRACT FROM AUTHOR]

This present study centers sensitively on the determination of the effect of natural turkey feather fibers (TFFs) loading on fundamental features (thermal, mechanical, water-uptake, and micro-structural) of thermoplastic polyurethane (TPU). The composites with different TFFs contents (3, 6, 9, and 12 wt.%) were fabricated by the melt blending method using the twin screw extruder and micro-injection molder. The samples were characterized by means of differential scanning calorimeter (DSC), universal mechanical (tensile and hardness) tester, water-uptake, and scanning electron microscope (SEM) techniques. The thermal analysis depicted that the melting temperatures of the soft and hard segments as well as the crystallinity degree of TPU increased consistently with the increase of TFFs loading level thanks to the formation of better close-packed TPU chains in the matrices. As for the mechanical test results, when compared neat TPU, the tensile strengths were reinforced by 26.8% and 19.7%, and the modulus increased by 6.6% and 45.1% for the composite samples including 3% and 6% of TFFs, respectively. However, drastic diminishment were observed at further contents. Additionally, TFFs loadings brought about gradual increase in the water-uptake capacities of the composites due to the increasing of the number of voids and omnipresent flaws in TPU matrices. The taken SEM images also revealed that, at low contents, there existed the enrichment of interfacial adhesion between TFFs and TPU matrix, whereas the morphological appearance of the composites get worse at high contents accompanied by the formation of micro-structural defects. [ABSTRACT FROM AUTHOR]

The main scope of this comprehensive study is to investigate the effects of poly(p‐benzophenoneoxycarbonylphenyl acrylate), poly(BPOCPA), which presenting as only graft units or both graft and ungrafted units in the matrix, on the fundamental features of isotactic polypropylene (IPP). The graft copolymerization of BPOCPA onto IPP was performed with the aid of bulk melt polymerization at varying monomer content levels ranging from 5% to 40%. The thermal behavior, crystal quality, mechanical performance, and surface morphology of the samples were investigated by means of differential scanning calorimeter, X‐ray diffractometer (XRD), universal mechanical test, and scanning electron microscope (SEM) techniques. Thermal analyses depicted that there existed the noteworthy enhancements in both crystalline melting temperatures and percent crystallinities of matrix polymers. Furthermore, according to XRD results, a and b parameters increased significantly at low percentages of the graft units, while the parameter c decreased in all products in consistence with the content. As for the mechanical characterization, the grafting led to remarkable improvements in modulus, tensile and impact strength of the products. SEM micrographs indicated that the samples were completely homogeneous without any phase separation and the products exhibited brittle nature with some ductility. [ABSTRACT FROM AUTHOR]