Determination of the tensile properties and biodegradability of cornstarch-based biopolymers plasticized with sorbitol and glycerol

In this study, the effects of various quantities of sorbitol and glycerol plasticizers (0%, 30%, 45%, and 60%) on cornstarch-based film were examined to develop a novel polymer for usage with biodegradable materials. The film was prepared using the casting process. According to the test findings, the application of the plasticizer concentrations affected the thickness, moisture content, and water absorption of the film. When plasticizer concentrations were increased to 60%, the tensile stress and Young’s modulus of plasticized films dropped regardless of plasticizer type. However, the thin film with addition of 30% sorbitol plasticizer demonstrated a steady value of Young’s modulus (60.17 MPa) with an increase in tensile strength (13.61 MPa) of 46%, while the lowest combination of tensile strength and Young’s modulus is the film that was plasticized with 60% glycerol, with 2.33 MPa and 16.23 MPa, respectively. In summary, the properties and performance of cornstarch-based film were greatly influenced by plasticizer types and concentrations. The finest set of features in this research appeared in the film plasticized with 30% sorbitol, which achieved the best mechanical properties for food packaging applications

Mechanical performance and applications of cnts reinforced polymer composites—A review

Developments in the synthesis and scalable manufacturing of carbon nanomaterials like carbon nanotubes (CNTs) have been widely used in the polymer material industry over the last few decades, resulting in a series of fascinating multifunctional composites used in fields ranging from portable electronic devices, entertainment and sports to the military, aerospace, and automotive sectors. CNTs offer good thermal and electrical properties, as well as a low density and a high Young’s modulus, making them suitable nanofillers for polymer composites. As mechanical reinforcements for structural applications CNTs are unique due to their nano-dimensions and size, as well as their incredible strength. Although a large number of studies have been conducted on these novel materials, there have only been a few reviews published on their mechanical performance in polymer composites. As a result, in this review we have covered some of the key application factors as well as the mechanical properties of CNTs-reinforced polymer composites. Finally, the potential uses of CNTs hybridised with polymer composites reinforced with natural fibres such as kenaf fibre, oil palm empty fruit bunch (OPEFB) fibre, bamboo fibre, and sugar palm fibre have been highlighted

Use of industrial wastes as sustainable nutrient sources for bacterial cellulose (BC) production: mechanism, advances, and future perspectives

A novel nanomaterial, bacterial cellulose (BC), has become noteworthy recently due to its better physicochemical properties and biodegradability, which are desirable for various applications. Since cost is a significant limitation in the production of cellulose, current efforts are focused on the use of industrial waste as a cost-effective substrate for the synthesis of BC or microbial cellulose. The utilization of industrial wastes and byproduct streams as fermentation media could improve the cost-competitiveness of BC production. This paper examines the feasibility of using typical wastes generated by industry sectors as sources of nutrients (carbon and nitrogen) for the commercial- scale production of BC. Numerous preliminary findings in the literature data have revealed the potential to yield a high concentration of BC from various industrial wastes. These findings indicated the need to optimize culture conditions, aiming for improved large-scale production of BC from waste streams

Hybridization of MMT/Lignocellulosic fiber reinforced polymer nanocomposites for structural applications: a review

In the recent past, significant research effort has been dedicated to examining the usage of nanomaterials hybridized with lignocellulosic fibers as reinforcement in the fabrication of polymer nanocomposites. The introduction of nanoparticles like montmorillonite (MMT) nanoclay was found to increase the strength, modulus of elasticity and stiffness of composites and provide thermal stability. The resulting composite materials has figured prominently in research and development efforts devoted to nanocomposites and are often used as strengthening agents, especially for structural applications. The distinct properties of MMT, namely its hydrophilicity, as well as high strength, high aspect ratio and high modulus, aids in the dispersion of this inorganic crystalline layer in water-soluble polymers. The ability of MMT nanoclay to intercalate into the interlayer space of monomers and polymers is used, followed by the exfoliation of filler particles into monolayers of nanoscale particles. The present review article intends to provide a general overview of the features of the structure, chemical composition, and properties of MMT nanoclay and lignocellulosic fibers. Some of the techniques used for obtaining polymer nanocomposites based on lignocellulosic fibers and MMT nanoclay are described: (i) conventional, (ii) intercalation, (iii) melt intercalation, and (iv) in situ polymerization methods. This review also comprehensively discusses the mechanical, thermal, and flame retardancy properties of MMT-based polymer nanocomposites. The valuable properties of MMT nanoclay and lignocellulose fibers allow us to expand the possibilities of using polymer nanocomposites in various advanced industrial applications

Effect of incorporation of sugar palm (Arenga Pinnata [Wurmb] Merr.) fiber from various geographical regions towards the tensile and flexural properties of SPF/epoxy composites for engineering applications

The objective of this study is to evaluate the tensile and flexural properties of epoxy composites reinforced with sugar palm (Arenga pinnata) fiber (SPF) harvested from various geographical locations, in Malaysia; Kuala Jempol, Negeri Sembilan (SPFN9); Benta, Pahang (SPFP); and Tawau, Sabah (SPFS), and from Java, Indonesia (SPFJ). Due to its optimal chemical composition, which includes a higher proportion of cellulose (44.53%), hemicellulose (10.01%) and lignin (41.97%), SPFN9/epoxy composites have the best tensile and flexural strength, according to this study, with 27.09 MPa and 54.44 MPa, respectively. The composites demonstrate slight decreases in the tensile strength (about 27–36%) and flexural strength (about 26%–42%) compared to the neat one. This is associated with the insufficient filling of the polymer amount. The hydrophilic characteristic of SPF makes it tough to bind to hydrophobic epoxy, creating a difficulty with interfacial adhesion between the filler and matrix. Thus, the SPF needed to be treated prior to the fabrication of composites to improve its mechanical properties for structural and automotive applications

Development of kenaf biochar in engineering and agricultural applications

The aim of this review is to investigate the recent development of kenaf derived biochar and its composites in various engineering and agricultural applications including nanostructure catalysts and polymer composites as kenaf biochar and activated carbon are mainly used as material adsorbents and soil amendments. A systematic review on the effect of process parameters of thermal decomposition, pyrolysis towards the production of desired biochar, therefore, is in crucial needs. Based on existing literature, the properties and production of kenaf biomass and resultant biochar are discussed in this paper. This analysis focuses on the unique characteristics of kenaf crops and the resulting biochar, which has a surprisingly large surface area and increased pore volume, to explain their prospective applications, whether in environmental utilization or engineering applications. Range of optimum surface areas for kenaf biochar are around 800–1000 m2/g where they show high adsorption properties. Whereas, the pore volume of activated carbon usually exceeds 1 cm3/g. Recent developments in engineered kenaf biochar technology and its future directions for research and development are also discussed

Low-Temperature Thermal Degradation of Disinfected COVID-19 Non-Woven Polypropylene—Based Isolation Gown Wastes into Carbonaceous Char

Yields of carbonaceous char with a high surface area were enhanced by decreasing the temperature to improve the conversion of hazardous plastic polypropylene (PP), the major component in abundantly used isolation gowns. This study applied pyrolysis with different low pyrolytic temperatures to convert disinfected PP-based isolation gown waste (PP-IG) into an optimised amount of char yields. A batch reactor with a horizontal furnace was used to mediate the thermal decomposition of PP-IG. Enhanced surface area and porosity value of PP-IG derived char were obtained via an optimised slow pyrolysis approach. The results showed that the amount of yielded char was inversely proportional to the temperature. This process relied heavily on the process parameters, especially pyrolytic temperature. Additionally, as the heating rate decreased, as well as longer isothermal residence time, the char yields were increased. Optimised temperature for maximum char yields was recorded. The enhanced SBET values for the char and its pore volume were collected, ~24 m2 g−1 and ~0.08 cm3 g−1, respectively. The char obtained at higher temperatures display higher volatilisation and carbonisation. These findings are beneficial for the utilisation of this pyrolysis model in plastic waste management and conversion of PP-IG waste into char for further activated carbon and fuel briquettes applications, with the enhanced char yields, amidst the COVID-19 pandemic

Treatments of natural fiber as reinforcement in polymer composites-a short review

The demand for environmental awareness, preserving nature and being beneficial for societal economics has attracted the attention of many researchers and industries to examine the potential usage of natural fibers. There are a lot of beneficial natural fiber sources in a wide range of applications in the composites industry. It is worth mentioning that the performance of natural fiber-reinforced composites can be tailored through a certain natural fiber treatment, and hybridization by employing an appropriate number of synthetic fibers or with other natural fibers. In addition to cost-effectiveness balance, a balance between environmental impacts and desired performance can be achieved by designing the composite based on the product requirements. Yet, certain drawbacks such as incompatibility with the hydrophobic polymer matrix, hydrophilic nature and the tendency to absorb moisture during processing greatly reduce the potential of natural fibers to be used as reinforcements in polymer composites. In this short review, the main results presented in the literature are summarized, focusing on the properties and challenges of natural fibers, the processing behavior of natural fiber treatments, and paying attention to the use of physical and chemical treatments for the improvement of fiber-matrix interaction as reinforcement for polymeric matrices (thermoplastics, thermosets and biodegradables)

Kompozyty na osnowie polimeru przewodzącego z udziałem nanorurek węglowych w czujnikach gazu DMMP – przegląd literatury

A number of recent terrorist attacks make it clear that rapid response, high sensitivity and stability are essential in the development of chemical sensors for the detection of chemical warfare agents. Nerve agent sarin [2-(fluoro-methyl-phosphoryl) oxypropane] is an organophosphate (OP) compound that is recognized as one of the most toxic chemical warfare agents. Considering sarin’s high toxicity, being odorless and colorless, dimethyl methylphosphonate (DMMP) is widely used as its simulant in the laboratory because of its similar chemical structure and much lower toxicity. Thus, this review serves to introduce the development of a variety of fabricated chemical sensors as potential sensing materials for the detection of DMMP in recent years. Furthermore, the research and application of carbon nanotubes in DMMP polymer sensors, their sensitivity and limitation are highlighted. For sorption-based sensors, active materials play crucial roles in improving the integral performances of sensors. The novel active materials providing hydrogen-bonds between the polymers and carbon nanotubes are the main focus in this review.Przeprowadzone w ostatnich latach liczne ataki terrorystyczne jasno wskazują, że w wypadku czujników do wykrywania chemicznych środków bojowych są niezbędne: ich wysoka czułość, szybka reakcja i stabilność. Środek paralityczno-konwulsyjny sarin (2-fluorometylofosforylooksypropan) to związek fosforoorganiczny (OP) uznawany za jeden z najbardziej toksycznych dostępnych chemicznych środków bojowych. Ze względu na to, że jest on bezwonny, bezbarwny, a ponadto bardzo toksyczny, w badaniach laboratoryjnych szeroko stosuje się jego symulator – metylofosfonian dimetylu (DMMP), o podobnej strukturze chemicznej i znacznie mniejszej toksyczności. W artykule przedstawiono rozwój technologii czujników chemicznych do wykrywania gazu DMMP. Omówiono badania dotyczące wykorzystania kompozytów polimerowych z udziałem nanorurek węglowych w czujnikach gazu DMMP. W wypadku czujników, w których wykorzystuje się zjawisko sorpcji, kluczową rolę w poprawie ich wydajności odgrywają materiały aktywne. W niniejszym przeglądzie skupiono się na nowatorskich materiałach aktywnych, w których występują wiązania wodorowe między polimerem a nanorurkami węglowymi

Determination of the Tensile Properties and Biodegradability of Cornstarch-Based Biopolymers Plasticized with Sorbitol and Glycerol

In this study, the effects of various quantities of sorbitol and glycerol plasticizers (0%, 30%, 45%, and 60%) on cornstarch-based film were examined to develop a novel polymer for usage with biodegradable materials. The film was prepared using the casting process. According to the test findings, the application of the plasticizer concentrations affected the thickness, moisture content, and water absorption of the film. When plasticizer concentrations were increased to 60%, the tensile stress and Young’s modulus of plasticized films dropped regardless of plasticizer type. However, the thin film with addition of 30% sorbitol plasticizer demonstrated a steady value of Young’s modulus (60.17 MPa) with an increase in tensile strength (13.61 MPa) of 46%, while the lowest combination of tensile strength and Young’s modulus is the film that was plasticized with 60% glycerol, with 2.33 MPa and 16.23 MPa, respectively. In summary, the properties and performance of cornstarch-based film were greatly influenced by plasticizer types and concentrations. The finest set of features in this research appeared in the film plasticized with 30% sorbitol, which achieved the best mechanical properties for food packaging applications