Papers by Keyword: Film

Abstract: Cissampelos pareira, locally known as Krueo Ma Noy or Monoi, is a traditional Thai medicinal plant whose leaf mucilage has long been used as an edible gel and dessert ingredient. The mucilage, a natural hydrophilic polymer produced by plant metabolism, possesses film-forming potential that could be useful in pharmaceutical applications. This study aimed to develop and evaluate the mechanical properties of films prepared from dried C. pareira leaf mucilage, with the incorporation of various plasticizers—glycerin (Gly), propylene glycol (PG), polyethylene glycol-400 (PEG-400), and low-protein natural rubber latex (LPNRL)—to enhance film flexibility and usability. The unplasticized mucilage film exhibited a high tensile strength of 15.81 ± 0.58 MPa but was brittle, with low elongation at break recorded at 1.62 ± 0.24 percent. The addition of plasticizers significantly improved film elasticity, increasing elongation to a range of 21.41 to 29.93 percent, while reducing tensile strength to between 6.10 and 10.73 MPa. Among the plasticizers tested, LPNRL showed the most favorable mechanical profile, providing a flexible yet sufficiently strong film structure. These results indicate that C. pareira mucilage, when properly modified, can serve as a sustainable and biodegradable alternative for use in pharmaceutical film formulations, including wound dressings, transdermal systems, or oral thin films.

Abstract: A vacuum-assisted thermal evaporation method for the preparation of undoped and Zn-doped erbium sesquiselenide Er₂Se₃ thin films on various substrates using independent elementary sources is developed. The electrophysical parameters, such as electrical resistivity and thermo-electromotive force of the films, are measured from 77 up to 650 K.

Abstract: Colorimetric intelligent food packaging requires an environmentally friendly biopolymer matrix with strong physical properties to retain anthocyanins as sensitive dyes effectively. This retention is crucial for enhancing the colorimetric response used in monitoring food freshness. The objective of this research is to investigate the physicochemical properties of intelligent food packaging films based on the mixing order of pectin and chitosan matrices, along with anthocyanins extracted from rambutan peels. Films were prepared from pectin (P), chitosan (C), pectin-chitosan (PC), pectin-anthocyanins (PA), chitosan-anthocyanins (CA), and various order of mixing film solution consists of pectin, chitosan, and anthocyanins, including pectin-chitosan-anthocyanins (PCA), pectin-anthocyanins-chitosan (PAC), and chitosan-anthocyanins-pectin (CAP). The results demonstrated that the CAP film exhibited favorable tensile strength (TS) of 2.3564 MPa and elongation at break (EAB) of 56.40%. Additionally, the CAP film retained a significant number of total anthocyanins after drying, with a content of 19.01 mg/100g, a total phenolic content (TPC) of 3439.63 mg/100g, and a radical scavenging activity (RSA) of 95.54%. Fourier transform infrared (FTIR) spectroscopy revealed spectral bands in the 3300-3600 cm⁻¹ and 1200-1250 cm⁻¹ regions, suggesting interactions or bonds between anthocyanins and either pectin or chitosan, possibly involving hydrogen bonding or modifications in C–O group structures. The color of the films changed across a pH range of 5–10, transitioning from pink to pale yellow and finally to greenish yellow. Based on these findings, the CAP film is identified as a promising candidate for colorimetric intelligent packaging applications.

Abstract: The purpose of this work is to enhance the performance of photoanode element in Dye-Sensitised Solar Cells (DSSC) by using a Response Surface Methodology (RSM) technique. Most of previous work related to photoanode enhancement have relied on the traditional method known as One Factor at a Time (OFAT), which has the limitation to evaluate the interaction effect for TiO₂ Thickness and dye molarity. To address this issue, RSM is used to model and optimize the performance of DSSC parameters by studying the relationship between two parameters namely TiO₂ film thickness and the concentration of N719 dye molarity . The RSM technique helps in finding the best mathematical model on how these parameters interact and affect the result of Power Conversion Efficiency (PCE). The result from this study shown that these two variables, TiO₂ film thickness at 10 µm and the concentration of N719 at 0.4mM are significant and generated the highest value of PCE at 2.86%, with high coefficient of determination R² (0.9983). The R² of 0.9983 is close to 1 shows the strong correlation between the variables TiO₂ film thickness and the concentration of N719 dye molarity.

Abstract: Graphenic carbon (GC) provides a potential ability as photovoltaic material due to its tunable properties. Here, we investigate the optical energy gap and the thickness of B-GC material as a p-type in solar cell application. The GC was prepared from old charcoal powders of coconut shells by heating process at 400°C and B-GC powders were prepared by wet mixing method using boric acid as B atom source. B-GC films were then prepared by employing nebulizer as a nanospraying method. All samples were examined through various characterization techniques such as X-Ray Diffarction (XRD), SEM cross section, and UV-Vis spectroscopy. The amorphous characteristic of B-GC is confirmed by broad peaks in XRD patterns, similar to that of reduced graphene oxide (rGO). The present of B along with O and dominant C elements is determined by SEM-EDX result. The B dopants affect the optical bandgap energy (E_g) of GC as an intrinsic material. The thickness of B-GC films was found to be thinner than in a previous study that used a similar method but different equipment. The average thickness of B-GC films is in the range of 127 to 420 nm, followed by an increase in the deposition time for 5 to 20 s. Estimation of the E_g value indicated that B-GC has an energy gap around 2 eV, which is most suitable as a window layer in solar cell applications.

Abstract: Natural rubber latex (NRL) with the deproteinized process was interesting for cosmetic and transdermal drug delivery systems because of its notable characteristics. The purpose of this study was to develop in situ cooling films from deproteinized natural rubber latex (DNRL). Menthol, camphor, and volatile oils were added into DNRL emulsions for cooling effect and pain relief. The pH, rheological properties, particle size, and zeta potential of emulsions were examined. Then, the time of film-formation, morphology, and mechanical properties of the cooling NRL films were evaluated. The resultant emulsions revealed that their pH was about 5.7 - 6.3. The viscosity was in the range of 1000 – 3000 cps and indicated the pseudoplastic flow. The increasing amount of olive oil reduced the particle size and increased the negatively zeta potential of those emulsions. The film formation time of specimens was about 4.5 - 6.5 mins. The cooling films demonstrated smoothness and homogeneity. The presence of olive oil increased the softness of films. The increasing of oil volume increased the elasticity; however, it decreased the ductility of the films. This in situ cooling DNRL film was also effective forward for the development of a transdermal drug delivery system.

Abstract: The impact resistance improvement is important for window glass to protect people from injury. Although it has been proved that the impact resistance of a glass plate can be improved easily by fitting a thin polymeric film, its mechanism has not been clarified yet. The purpose of this study is to clarify the reinforcing mechanism of the impact resistance of a glass plate by fitting a polymeric film. To clarify it, a numerical simulation model was built using ANSYS Autodyn to simulate the dynamic fracture of a glass plate fitted with a polymeric film. The simulation model and results were examined by comparing them to the experimental result in the previous study. The Johnson-Holmquist (JH2) damage model was used for the constitutive law of the glass plate. A polymeric film with 0.2 mm thickness (3% with the glass plate) was modeled at the non-impact surface of the glass plate. The nodes of the glass plate at the interface with the film connected the nodes of the film by perfect bonding. By comparing the simulation results to the experiment, it was indicated the importance of modeling the remaining fragments of the glass plate and the adhesive layer of the film in simulating the dynamic fracture of the glass plate fitted with polymeric film.

Abstract: A series of liquid crystal elastomer (LCE) films (ABC films) were prepared by polymerization of polymethylhydrosiloxane (PMHS), liquid crystal (LC) monomer cholesterol 4-(allyloxy) benzoate (M_B) and cross-linking agent 4'-(undec-10-enoyloxy)-[1,1'-biphenyl]-4-yl dodec-11-enoate (M_C) . The chemical structures and LC properties of the monomers and polymers were characterised by Fourier Transform Infrared Spectrometer (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TG), polarized optical micrograph (POM) and X-ray diffractometer (XRD). M_B is a cholesteric LC and M_C is a smectic LC. The ABC films are cholesteric LCEs. The temperature at which 5% weight loss occurred for the ABC films are around 300 °C. The glass transition temperature of ABC films increases with the increase of LC monomer M_B content. The ABC films have a strong absorption around 200-330nm in the ultraviolet (UV) region, and the absorption range does not change with temperature.

Abstract: Petroleum-based polymers have significantly problems to the environment due to it cannot degrade in the nature. Biopolymer become to interesting materials for replacing these materials for overcome these disadvantages. Here, we intend to study the biocomposite films of polylactic acid (PLA) blend polybutylene succinate (PBS) composited with ZnO nanoparticles. The chemical reaction and the water absorbency of biocomposite films were investigated by FT-IR spectroscopy and swelling ratio, respectively. The FT-IR results showed that the biocomposite films did not have any chemical reactions between polymers chains and ZnO nanoparticles. The swelling ratio of biocomposite films have proportionally with the contact time. The photocatalytic activity of biocomposite film was investigated by the methylene blue degradation in the aqueous solution. It was found that the efficacy of photocatalytic activity increased with increases in the contact time.

Abstract: Structure of amorphous carbon can be composed of sp² (graphite), or sp³ (diamond), or a combination of both, depending on their fractions. Therefore, many researchers were exploring to use it as solar cell material. This research used the amorphous carbon of bio-product as a basic material in the form of palmyra sugar which was synthesized through the heating and doping process to produce n-type and p-type semiconductors. This research aims to analyze the effect of dopant and deposition time on electrical properties. The heating process was carried out at 250°C and the doping process was carried out by adding NH₄OH for a-C:N and H₃BO₃ for a-C:B. The deposition process was carried out by the nano-spray method using a variety of deposition time on the ITO substrate. The result of scanning electron microscopy (SEM) showed that the film thickness increased with the increase of deposition time. Besides, the result of four-point probe (FPP) showed that the dopant can increase electrical conductivity, but the film thickness did not influence it. The electrical conductivity obtained was 5x10^-1 - 6x10^-1 S/cm. And the result of further analysis, it can be concluded that electrical conductivity was still in the range of semiconducting material.