Polycaprolactone (PCL) is one of the most used synthetic polymers for medical applications due to its biocompatibility and slow biodegradation character. Combining the inherent properties of the PCL matrix with the characteristic of nanofibrous particles, result into promising materials that can be suitable for different applications, including the biomedical applications. The advantages of nanofibrous structures include large surface area, a small diameter of pores and a high porosity, which make them of great interest in different applications. Electrospinning, as technique, has been heavily used for the preparation of nano- and micro-sized fibers. This review discusses the different methods for the electrospinning of PCL and its composites for advanced applications. Furthermore, the steady state conditions as well as the effect of the electrospinning parameters on the resultant morphology of the electrospun fiber are also reported.

Over the past decades, research has escalated on the use of polylactic acid (PLA) as a replacement for petroleum-based polymers. This is due to its valuable properties, such as renewability, biodegradability, biocompatibility and good thermomechanical properties. Despite possessing good mechanical properties comparable to conventional petroleum-based polymers, PLA suffers from some shortcomings such as low thermal resistance, heat distortion temperature and rate of crystallization, thus different fillers have been used to overcome these limitations. In the framework of environmentally friendly processes and products, there has been growing interest on the use of cellulose nanomaterials viz. cellulose nanocrystals (CNC) and nanofibers (CNF) as natural fillers for PLA towards advanced applications other than short-term packaging and biomedical. Cellulosic nanomaterials are renewable in nature, biodegradable, eco-friendly and they possess high strength and stiffness. In the case of eco-friendly processes, various conventional processing techniques, such as melt extrusion, melt-spinning, and compression molding, have been used to produce PLA composites. This review addresses the critical factors in the manufacturing of PLA-cellulosic nanomaterials by using conventional techniques and recent advances needed to promote and improve the dispersion of the cellulosic nanomaterials. Different aspects, including morphology, mechanical behavior and thermal properties, as well as comparisons of CNC- and CNF-reinforced PLA, are also discussed.

The need for utilization of environmentally friendly materials has emerged due to environmental pollution that is caused by non-biodegradable materials. The usage of non-biodegradable plastics has increased in the past decades in many industries, and, as a result, the generation of non-biodegradable plastic wastes has also increased. To solve the problem of non-biodegradable plastic wastes, there is need for fabrication of bio-based polymers to replace petroleum-based polymers and provide strategic plans to reduce the production cost of bioplastics. One of the emerging bioplastics in the market is poly (butylene succinate) (PBS) and it has been the biopolymer of choice due to its biodegradability and environmental friendliness. However, there are some disadvantages associated with PBS such as high cost, low gas barrier properties, and softness. To lower the cost of PBS and enhance its properties, natural lignocellulosic fibers are incorporated into the PBS matrix, to form environmentally friendly composites. Natural fiber-based biocomposites have emerged as materials of interest in important industries such as packaging, automobile, and construction. The bonding between the PBS and natural fibers is weak, which is a major problem for advanced applications of this system. As a result, this review paper discusses various methods that are employed for surface modification of the Fibers The paper provides an in-depth discussion on the preparation, modification, and morphology of the natural fiber-reinforced polybutylene succinate biocomposites. Furthermore, because the preparation as well as the modification of the fiber-reinforced biocomposites have an influence on the mechanical properties of the biocomposites, mechanical properties of the biocomposites are also discussed. The applications of the natural fiber/PBS biocomposites for different systems are also reported.

The utilization of layered nanofillers in polymer matrix, as reinforcement, has attracted great interest in the 21st century. This can be attributed to the high aspect ratios of the nanofillers and the attendant substantial improvement in different properties (i.e., increased flammability resistance, improved modulus and impact strength, as well as improved barrier properties) of the resultant nanocomposite when compared to the neat polymer matrix. Amongst the well-known layered nanofillers, layered inorganic materials, in the form of LDHs, have been given the most attention. LDH nanofillers have been employed in different polymers due to their flexibility in chemical composition as well as an adjustable charge density, which permits numerous interactions with the host polymer matrices. One of the most important features of LDHs is their ability to act as flame-retardant materials because of their endothermic decomposition. This review paper gives detailed information on the: preparation methods, morphology, flammability, and barrier properties as well as thermal stability of LDH/polymer nanocomposites.

Alginate has been a material of choice for a spectrum of applications, ranging from metal adsorption to wound dressing. Electrospinning has added a new dimension to polymeric materials, including alginate, which can be processed to their nanosize levels in order to afford unique nanostructured materials with fascinating properties. The resulting nanostructured materials often feature high porosity, stability, permeability, and a large surface-to-volume ratio. In the present review, recent trends on electrospun alginate nanofibers from over the past 10 years toward advanced applications are discussed. The application of electrospun alginate nanofibers in various fields such as bioremediation, scaffolds for skin tissue engineering, drug delivery, and sensors are also elucidated.

Composites based on ethylene vinyl acetate (EVA) copolymers with 18% and 28% VA contents and empty fruit bunch (EFB) fibre were reported in this study. The EVA-EFB composites were prepared by melt mixing using a Brabender plastograph mixer. Scanning electron microscopy (SEM) results show an improved extent of interfacial adhesion between the polymer and the fibre, with an increase amount of VA in the copolymers. Differential scanning calorimetry (DSC) results reveal that the melting and crystallization enthalpies decreased significantly with increasing VA content, while the presence of EFB fibre had very little influence on the melting and crystallization behaviour of both EVA18 and EVA28. Thermogravimetric analysis (TGA) results show that EVA18 is more thermally stable than EVA28 due to the higher amount of VA in EVA28, and the decomposition of EFB fibre seems to be retarded when it is incorporated into the EVA copolymers. Dynamic mechanical analysis (DMA) results show that both the storage modulus and loss modulus decrease significantly with an increase in VA content, and that these two properties observably increased with the incorporation of the fibre. The glass transition temperature also increased observably with increasing fibre loading, and decreased with an increase in the VA content. The stress and strain at break showed a similar decrease with increasing fibre content for both EVA18 and EVA28, while Young's modulus increased much more significantly with increasing fibre content for EVA28. Generally, it seems as if the improvement in interaction between EVA28 and EFB was not significant enough to overcome the inherent weak properties of EVA28.

It is well known that polymers are insulators, which limit their usage in other applications where thermal conductivity is essential for heat to be efficiently dissipated or stored. In the past, the improvement in the thermal conductivity of polym.rs with conductive fillers has been investigated by researchers. Carbon-based materials such as graphite, graphene and carbon nanotube, which feature excellent properties such as a high mechanical strength, a high thermal conductivity and a tailorable electronic configuration, have been added to different polymer matrices to enhance their thermal conductivity. Amongst others, graphite more especially expanded graphite merits special interest because of its abundant availability at a relatively low cost and lightweight when compared to other carbon allotropes. Herein, we describe the thermal conductivity of polymer/graphite composites and their applications.

Recently, the development of a unique class of layered silicate nanomaterials has attracted considerable interest for treatment of wastewater. Clean water is an essential commodity for healthier life, agriculture and a safe environment at large. Layered double hydroxides (LDHs) and other clay hybrids are emerging as potential nanostructured adsorbents for water purification. These LDH hybrids are referred to as hydrotalcite-based materials or anionic clays and promising multifunctional two-dimensional (2D) nanomaterials. They are used in many applications including photocatalysis, energy storage, nanocomposites, adsorption, diffusion and water purification. The adsorption and diffusion capacities of various toxic contaminants heavy metal ions and dyes on different unmodified and modified LDH-samples are discussed comparatively with other types of nanoclays acting as adsorbents. This review focuses on the preparation methods, comparison of adsorption and diffusion capacities of LDH-hybrids and other nanoclay materials for the treatment of various contaminants such as heavy metal ions and dyes.