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The purpose of this paper is to investigate the effects of coupling agents on the structure and properties of the nanocomposite films and clarify their mechanism. Polyimide (PI)/Al₂O₃ nanocomposite films were prepared using different coupling agents.

Poly(amic acid) (PAA) was firstly synthesised from appropriate pyromellitic diannanocomposite and oxydianiline in N‐dimethylacetamide. Calculated amount of nano‐Al₂O₃ particles modified by different coupling agents (KH550, KH560, KH570 and AE3012) were added to PAA solution by an ultrasonic‐mechanical method and PI/nano‐Al₂O₃ film was fabricated by heat curing. The microstructure, thermal stability, mechanical properties and electric breakdown strength of the films were characterised.

The addition of coupling agents could greatly improve the dispersion homogeneity of Al₂O₃ nano‐particles in PI matrix. Results of corresponding characterisations indicated that both the thermal stability and mechanical properties of PI/Al₂O₃ nanocomposite film with KH550 were greater/better than others, while AE3012 could improve the electric breakdown strength.

In the present discussion, the effects of different coupling agents, KH550, KH560, KH570 and AE3012, were investigated. Results of this research work would be beneficial to an in‐depth understanding on the relationship between microstructure and properties of PI composites, and further promote the development of the high‐performance PI insulating materials.

The four coupling agents, KH550, KH560, KH570 and AE3012, were firstly used to disperse the nano‐Al₂O₃ particles in PI matrix. The effects of coupling agents on microstructure and properties of composites were discussed by the authors in detail.

Indium tin oxide (ITO) is a material belonging to the group of transparent conductive oxides, which are widely used in many fields of technology including optoelectronics and photovoltaics. However, the properties of ITO thin films depend on many factors. Therefore, the aim of the study was thorough investigation of the properties of sputtered ITO thin films of various thicknesses.

ITO coatings were deposited by magnetron sputtering in pure argon atmosphere using ceramic ITO target. Various deposition times resulted in obtaining thin films with different thickness, which had significant influence on the optoelectronic properties of deposited coatings. In this work the results of investigation of structural, surface, optical and electrical properties were presented.

Increase of the coating thickness caused change of the microstructure from amorphous to nanocrystalline and occurrence of grains with a size of 40 to 60 nm on their surface. Moreover, the fundamental absorption edge was red-shifted, whereas the average transmission in the visible wavelength range remained similar. Increase of the thickness caused considerable decrease of the sheet resistance and resistivity. It was found that even thin films with a thickness of 10 nm had antistatic properties.

The novelty and originality of presented work consists in, among other, determination of antistatic properties of ITO thin films with various sheet resistances that are in the range typical for dielectric and semiconducting material. To date, there are no reports on such investigations in the literature. Reported findings might be very helpful in the case of, for example, construction of transparent antireflective and antistatic multilayers.

The purpose of this paper is to analyse the properties of bacterial cellulose (BC) film, obtained through Kombucha tea fermentation.

Kombucha fungus was used to produce BC film under static cultivation conditions. Physical and mechanical properties under the influence of drying temperature and durability of BC material were investigated. Tensile properties were estimated by TINIUS OLSEN H10 KT test machine according to ISO 3376:2011, thickness was measured by DPT 60. BC structure was analysed by Scanning Electron Microscopy Quanta 200 FEG.

BC material with excellent deformation properties in wet state were obtained by fermenting Kombucha tea. Due to the presence of fermentation residues, Kombucha film is sensitive to drying temperature. The best deformation properties retain when BC material is dried at low temperature (about 25°C). BC material becomes stiffer and ruptures at lower deformations due to rapid water evaporation at higher drying temperature. It is confirmed that during time, the properties of BC film changes significantly and there may be problems with the durability of products from this material. BC film has an interesting set of properties, therefore its application to fashion industry without further preparation is limited.

A new approach is based on the evaluation of Kombucha material properties and investigation of BC as new type of material for fashion industry. Some recommendations for Kombucha BC film production are provided, basing on gained experience, experimental results and analysed literature. The advantages and disadvantages of material are discussed in the paper, in order to search for the ways to adapt the new type of material to fashion business.

The purpose of this paper is to present an overview of functional properties of the polysaccharide-based component and their application in developing edible film and coating for the food processing sector.

In this review study, approximately 271 research and review articles focusing on studies related to polysaccharide-based components and their film-forming properties. This article also focused on the application of polysaccharide-based edible film in the food sector.

From the literature reviewed, polysaccharide components and components-based edible film/coating is the biodegradable and eco-friendly packaging of the materials and directly consumed by the consumer with food. It has been reported that the polysaccharide components have excellent properties such as being nontoxic, antioxidant, antimicrobial, antifungal and with good nutrients. The polysaccharide-based edible film has lipid and gas barrier properties with excellent transparency and mechanical strength. In various studies, researchers worked on the development of polysaccharide-based edible film and coating by incorporating plant based natural antioxidants. This was primarily done for obtaining improved physical and chemical properties of the edible film and coating. In future, the technology of developing polysaccharide-based edible film and coating could be used for extending the shelf life and preserving the quality of fruits and vegetables at a commercial level. There is more need to understand the role of edible packaging and sustainability in the food and environment sector.

Through this review paper, possible applications of polysaccharide-based components and their function property in the formation of the edible film and their effect on fruits, vegetables and other food products are discussed after detailed studies of literature from thesis and journal article.

Protein-based films have good barrier characteristics against gas compared to synthetic films, but they have poor mechanical properties and high water vapour permeability (WVP) due to their hydrophilic nature. Sugarcane bagasse (SCB) is available abundantly in Southeast Asian countries and can be potentially utilized for its cellulose to increase the stiffness of the film. Hence, the purpose of this study was to develop a gelatine-based film from chicken feet incorporated with SCB.

Film-forming solutions (FFS) from chicken feet gelatine with different percentages of glycerol (25 and 35 per cent) were prepared by casting 4.0 g of FFS onto a rimmed silicone resin plate (50 × 50 mm²). Cellulose from SCB was purified and used to prepare hydrolyzed SCB. Films with 35 per cent glycerol were selected to be incorporated with different weight percentages (2.5, 5.0, 7.5 and 10.0 per cent) of hydrolyzed SCB to increase the tensile strength (TS) and lower the WVP of the films. Mechanical properties, colour and transparency of the films were also tested.

Films containing 35 per cent glycerol have lower TS but higher elongation at break compared to films prepared with 25 per cent glycerol. There were no significant differences between the films with 25 per cent and 35 per cent glycerol in thickness, WVP and transparency value tests. Film incorporated with 5.0 Wt.% SCB had a slight increment in TS (23.07 MPa) compared to the control film (22.50 MPa). WVP was also lowered from 2.18 × 10⁻¹¹gm⁻¹s⁻¹Pa⁻¹ to 1.85 × 10⁻¹¹gm⁻¹s⁻¹Pa⁻¹. The other properties, namely, thickness, colour measurement and transparency value, were significantly different (p < 0.05) but nearer to the properties of the control film.

This study incorporates hydrolyzed SCB to study the potential mechanical benefits in protein-based bio-films. There is potential to utilize agricultural waste (chicken feet and SCB) to develop food packaging films.

The purpose of this paper is to improve anti-corrosion, self-cleaning, hydrophily and sterilization properties of aluminum (Al) alloy.

A multifunctional coating for medical external application on Al alloy had been prepared by anodic oxidation, electrolytic coloring silver (Ag) and sealed in boiling water with nano-sized titanium dioxide (TiO₂) particles. The multifunctional coating was characterized by X-ray diffraction, scanning electron microscope and energy dispersive spectroscopy. Other properties such as corrosion-resistance, wipe-resistance, hydrophilicity, photochemical decomposition and bactericidal antiseptic effect were also investigated.

The results demonstrate that a golden film with multi-function had been obtained for medical external application. The main phase of coating is amorphous Al₂O₃, and nano-sized silver particle is electrodeposited in bottom of film hole, while nano-sized TiO₂ is sealed on the external surface of coating. The properties of film, such as anti-corrosion, self-cleaning, hydrophily, sterilization are better than those of Al alloy substrate.

Considering about this usage for medical external application, a multifunctional coating which has the properties such as decoration, anti-corrosion, sterilize and self-cleaning has been first prepared on Al alloy surface in the study. This coating would meet the requirements of medical external using and provide theoretical and practical foundation about Al alloy for medical use.

The purpose of this paper is to describe the synthesizing of polyesteramide (PEA) resins using an acid functional acrylic copolymer (ACR) and hydroxy ethyl fatty amide (HEFA) of dehydrated castor oil (DCO) and to study the effect of HEFA on the performance properties of the coating films of PEA resins.

The PEA resins are synthesised by using ACR (synthesised by using butyl methacrylate (BMA) and maleic anhydride (MA)), and HEFA. Different formulations are developed by using ACR and HEFA. The coatings are made using xylene/acetone as a solvent. These coatings are applied on mild steel panels and are cured at 110°C. Various mechanical, optical and chemical properties of the coating films are evaluated.

The study reveals that, HEFA of DCO is used successfully as a cross‐linking agent for the ACR to form the PEA resins. Incorporation of long chain fatty acid (C₁₈) moieties of the fatty amide in the PEA resins backbone is thought to serve as flexibliser, which lead to improved mechanical and chemical properties of the films. The optimum results are obtained from composition three of copolymer A having (3:1) (ACR:HEFA) molar ratio.

The PEA resins synthesised here are made up of ACR (synthesised by using BMA and MA), and HEFA of DCO. Besides, this ACRs can be synthesised from acrylic acid. In addition to this, one can also use HEFA synthesised from other oils.

This method provides a simple solution for the synthesis of PEA resins and resulting to their improved mechanical properties. The developed product is also an environment friendly product.

The method developed here for the synthesis of PEA resins form ACRs and HEFA is unique and can be used as an effective surface coating material. These studies will help to develop low volatile organic compounds product which could find numerous industrial applications in surface coatings for metal surfaces.

This paper aims to investigate how ball milling (BM) and load influence transfer film on counterbody and the correlation between transfer film and tribological properties of copper-based composites.

The copper-based mixed powders preprocessed by BM for different times were used to manufacture sintered materials. Specimens were tested by a custom pin-on-flat linear reciprocating tribometer and characterized prior and after tests by optical microscope, scanning electron microscope and energy-dispersive spectroscopy. Image J® and Taylor-hobson-6 surface roughness meter were used to quantify the coverage and thickness of the transfer film.

Main results show that an appropriate amount of BM time and applied load can contribute to the formation of the transfer film on counterbody and effectively improve the tribological properties of the copper-based material. The transfer film coverage is linearly related to the friction coefficient, thickness of transfer film and wear volume. As the transfer film coverage increases, the coefficient of friction decreases. As the thickness of the transfer film increases, the amount of wear increases.

This work intends to control and optimize the formation of transfer film, thereby helping improve the tribological properties of materials and providing a reference to guide the preparation of Cu-based composites with excellent tribological properties.

The purpose of this paper is to improve the properties of shellac by blending with novolac and to study the thermal behaviour of the blends with an ultimate aim to use as surface coating material.

Novolac was synthesized by reaction of phenol with formaldehyde in a molar ratio of 1:0.8, in acidic condition. Blending of shellac with novolac was done in solution and films of the blends, prepared on glass slides and tin panels, were baked at 150°C for 15 minutes. Properties of the films were studied as per standard procedures.

Films of shellac‐novolac blends showed improvement in gloss and impact resistance compared to those of shellac alone. Gloss of blends increased with the increase in concentration of novolac and further increased on baking the films. Scratch hardness of shellac decreased on blending with novolac. Baked films of the blends showed resistance to heat and water. Films of shellac‐novolac blends were found to be more resistant to polar solvents compared to non‐polar solvents.

Shellac, prepared from kusmi seedlac, was used in the study. Besides shellac, dewaxed decolorized lac (DDL), dewaxed lac (DL) and bleached lac (BL) could also be used for study on blending with novolac.

Blending of shellac with novolac improved the film properties of shellac. The study suggests that the compositions can be utilised in developing formulations of coating material with improved properties for metal surfaces.

The formulations based on modification of shellac with novolac and study of the film properties utilising various instruments are novel. The formulations based on shellac and novolac can find applications in the field of surface coating with desired purposes.

The purpose of this study was carried out to explore the potential use of carrageenan extracted from marine red seaweed (Kappaphycus alvarezii) collected from Munaikadu, Mandapam region, Ramanathapuram district, Tamil Nadu.

Biodegradable film was developed by using carrageenan extracted by using alcohol extraction method. To improve the mechanical properties of the film, rice starch was incorporated. The biodegradable films were made by phase inversion method with varied carrageenan concentration of 1%, 1.5% and 2% (w/v) and rice starch with concentration of 0%, 1%, 1.5% and 2% (w/v). Physical properties, optical properties, mechanical properties and other properties such as biodegradability, solubility and water vapor permeability of the developed biodegradable films were characterized. The results were analyzed in design expert software using Box–Behnken design.

Results show that the biodegradable film’s mechanical and water vapor permeability increases with an increase in carrageenan and rice starch concentration. The optimized film structure was obtained with carrageenan and rice starch composition of 1.5% and 2%, respectively.

The results shown a broad spectrum of commercial applications and future rice starch possibilities incorporated in the carrageenan-based biodegradable film.