Biocarbon Polymer Composites

For applications involving sustainable materials, bio-nanocarbon was examined as a material to improve the properties of fiber-reinforced nano-biocomposite. A thorough investigation has been conducted using nano biocarbon as a filler and reinforcing material. However, the composite's inferior mechanical, physical, and thermal properties are a result of a poor fiber-matrix interface. As a result, in this study, biocarbon nanoparticles were created and used as functional components to enhance the properties of polymeric composite materials. To emphasize the scientific and technological issues that need to be resolved in order to create artificial composites with bio-inspired structures, recent studies of bio-inspired nano-carbon composites are discussed in this study. These include the production techniques for resolving the nanocarbon dispersion problem and creating bio-inspired structures, as well as the microstructure and composite characteristics characterization. In order to reveal natural design principles and serve as a resource for future research, bio-inspired composites and their applications are thoroughly examined and explained.

To fulfill the current circular economy concept, several attempts to reuse and valorize wastes and by-products coming from different sectors (such as the agri-food, textile, and packaging industries, among others) are being carried out at least at a lab scale by academics, despite the increasing interest that also involves the industrial world. One of the up-to-date strategies to transform wastes and by-products into new added-value systems refers to the production of biochar (BC), a carbonaceous solid residue derived from the thermo-chemical conversion, under controlled conditions, of wastes or, more generally, biomasses. Apart from its conventional uses (such as for soil remediation, heat and power production, low-cost carbon sequestration, and as a natural adsorbent, among others), BC is gaining a continuously increasing interest as a multifunctional micro-filler for different thermoplastic and thermosetting polymer matrices. Undoubtedly, the wide possibility of producing BC from different biomass sources, wastes, and by-products offers an attractive prospect toward a circular bioeconomy with “zero waste”. When incorporated into a polymer at different loadings, BC can provide thermal and electrical conductivity, EMI shielding features, enhanced mechanical properties, and flame retardance as well. This chapter aims to summarize the current achievements in the design, preparation, and characterization of thermoplastic polymer/biochar composites, discussing the current limitations/ drawbacks, and providing the reader with some perspectives for the future. 

Biomass-derived waste management has become an increasingly pressing concern due to rising levels of environmental issues. As a result, interest has risen in finding ways to turn biomass wastes into useful products. The conversion of biowaste into biochar is one of the efficient and environmentally friendly methods of disposing of biowaste. Developing polymer composites by reinforcing biochar as the filler material is gaining popularity due to their affordability and exceptional thermal and mechanical properties. Animal waste is one of the biomass wastes that can be converted into biochar and can be used in various applications. This review work aimed at synthesizing biochar from animal wastes, preparing polymer composites, and analyzing the thermo-mechanical properties. This review also focuses on various animal feedstocks for the synthesis of biocarbon and methods to fabricate polymer composites. The biocarbon-induced polymer composites showed an improvement in mechanical and thermal properties with varying percentages of loading.

Food loss due to wastage is a severe issue for the entire world. Wastage accounts for up to one-third of lost food output globally. Although there are various ways to turn food waste into useful functional materials, landfilling is still a frequent practice. This results in greenhouse gas emissions, which increase the already significant greenhouse gas emissions linked to the agriculture sector. In this review, we start by identifying multiple biomass sources and synthesis methods for biochar made from biomass. This contains methods for the characterization of phase change polymer nanocomposite materials impregnated with biochar. In order to compare the thermal properties of phase change materials and gain an understanding of the various biowastes, a comprehensive methodology was used.

Fused Deposition Modeling (FDM) is a solid-based 3D printing process. It is one of the additive manufacturing technologies that is used to create a threedimensional (3D) object using a CAD model. In the FDM process, raw material also known as filament, is initially in the solid state. Nowadays, biocarbon-incorporated polymer-based nanocomposite is used as a filament in the FDM process, due to the enhanced strength of the base polymer. In this paper, a review of carbon extracted from natural waste, such as tea powder, coffee grounds, egg shells, ocean plastic, coconut shells, etc., is presented The extraction procedure of biocarbon is given in detail. The results indicate that the strength enhancement of polymers can be achieved by incorporation of derived carbon from industry as well as agriculture waste. In addition, biocarbon-based polymer nanocomposite filaments in the FDM process can be developed by reinforcing the polymer matrix with carbon nanoparticles. Future work of this review process will explore the biobased carbon from various waste resources. The application of biocarbon-based polymer nanocomposites for the 3D printing process is highlighted.

The use of carbonaceous fillers in polymeric biocomposite materials has been widely studied due to their potential to add better engineering properties to biocomposites and expand their field of applications. Currently, due to the growing global concerns over environmental pollution and climate change, carbonaceous fillers derived from biomass are the preferred choice for production of the sustainable biocomposite materials. Rice husk ash (RHA), an abundant and sustainable carbonaceous filler obtained from the burn of rice husk in kilns of the processing rice was incorporated into the PBAT/PLA blend. The influence of RHA loading on the tensile properties of FDM-3D printed samples was investigated. Neat PBAT/PLA filament and its biocomposite filaments with 2.5, 5.0 and 7.5 wt. % RHA were prepared by the extrusion process. The filaments were characterized by FTIR, TG, and SEM. FDM-3D printed specimens were subjected to tensile tests. 

In the past 20-25 years, biochar has been promoted as a valuable resource of a carbon filler in polymer composites, sustainable agriculture, and environmental quality protection given its improved porous structure and electrochemical properties in comparison to other carbon-based materials. Recent works focusing on biochar and biochar-based nanocomposites are highlighting such properties and are even enhanced with nanotechnology. The higher porosity attributed to biochar is highlighted along with its great electrochemical properties able to retain nutrients for longer and favors their slow release. The use of biochar as a filler material to improve the electrical conductivity properties of polymers and the emphasis on various parameters, such as pyrolysis temperature, the type of feedstock, and compaction pressures on the electrical conductivity of the resultant composites are discussed.

With the advancement toward global sustainability, there is a widespread demand for sustainable materials that can be used for various applications. Carbon has gained much attention in the past few decades due to its scope of utilization in energy and environment related applications. Biomass resources are considered a prominent precursor for the synthesis of carbon-based materials due to their availability and economic viability. In this study, high-quality graphitic carbon is synthesized from Coconut Shell Powder (CSP) by pyrolysis and reinforced into a low-density polyethylene (LDPE) matrix for fabricating films for packaging applications. A custom-built high-temperature autogenic pressure reactor was used for conducting the pyrolysis to synthesize carbon from the coconut shell powder and a blown film extruder was used for fabricating composite films. For preparing the films, coconut shell powder-derived carbon was added to the LDPE matrix at various weight percent loadings of 0.25, 0.5, and 1 wt.%, respectively. Various analytical techniques such as scanning electron microscopy, X-ray diffraction, Raman spectroscopy, thermogravimetric analysis, tensile test, and differential scanning calorimetry were used for studying the properties of carbon and LDPE/carbon composite films. Upon adding carbon as fillers, there were significant improvements in the tensile and thermal degradation properties of the polymer carbon composite films. Upon the incorporation of carbon into the LDPE matrix, the crystallinity and tensile strength were found to improve by a maximum of 29% and 13%, respectively.

The world at large has acknowledged the importance of environmental issues. The depletion of natural resources, such as drinking water, and the emission of greenhouse gases that result in climatic change and the deterioration of human health, are the primary concerns. As urban areas expand rapidly, they exert enormous strain on nearby water supplies, leading to a global freshwater demand surge that is outpacing population expansion. The development of polymer nanocomposites has contributed significantly to the search for viable answers to pressing ecological concerns. Their ability to eradicate pollutants, including gas emissions, heavy metals, and dyes in wastewater has garnered researchers’ attention. In this overview, polymer nanocomposites, as well as the composites reinforced with biocarbon that are used in environmentally friendly ways, are discussed in detail. The adsorption mechanism and applications of polymer nanocomposites for the removal of hazardous metal ions and dyes were also studied.