Agro-wastes are derived from diverse sources including grape pomace, tomato pomace, pineapple, orange, and lemon peels, sugarcane bagasse, rice husks, wheat straw, and palm oil fibers, among other affordable and commonly available materials. The carbon-rich precursors are used in the production bio-based polymers through microbial, biopolymer blending, and chemical methods. The Food and Agriculture Organization (FAO) estimates that 20–30% of fruits and vegetables are discarded as waste during post-harvest handling. The development of bio-based polymers is essential, considering the scale of global environmental pollution that is directly linked to the production of synthetic plastics such as polypropylene (PP) and polyethylene (PET). Globally, 400 million tons of synthetic plastics are produced each year, and less than 9% are recycled. The optical, mechanical, and chemical properties such as ultraviolet (UV) absorbance, tensile strength, and water permeability are influenced by the synthetic route. The production of bio-based polymers from renewable sources and microbial synthesis are scalable, facile, and pose a minimal impact on the environment compared to chemical synthesis methods that rely on alkali and acid treatment or co-polymer blending. Despite the development of advanced synthetic methods and the application of biofilms in smart/intelligent food packaging, construction, exclusion nets, and medicine, commercial production is limited by cost, the economics of production, useful life, and biodegradation concerns, and the availability of adequate agro-wastes. New and cost-effective production techniques are critical to facilitate the commercial production of bio-based polymers and the replacement of synthetic polymers.

The fundamental objective of the review article was to explore the ecological sustainability of greenhouse covering material based on the following themes; considerations for greenhouse materials, properties of polymers and glass, additives, fillers, stabilizers and reinforcements, performance, Ultraviolet (UV) transmittance, phase change materials (PCMs), and environmental sustainability. A comparison of various polymers (polyvinyl chloride (PVC), acrylic, D-polymer, Linear low-density polyethylene (LLDPE), polyolefins), and silica glasses illustrated that each type of greenhouse cladding material has its unique merits and limitations. The performance of silica glasses, PVC, polyolefins was influenced by weather, greenhouse design, plant under cultivation, percentage UV transmittance, incorporation of additives and stabilizers, reinforcements, and integration of photovoltaic panels into the greenhouse roof among other factors. Polymers can be customized to achieve 0%UV transmittance, slow-insecticide release, and anti-microbial properties. In contrast, glass materials are preferred based on suitable photosynthetically active radiation (PAR) transmittance and near-infrared (NIR) reflection and less risk of photo-oxidation. From an ecological perspective, polymers can be recycled via mechanical and chemical recycling, closed-loop cycling, and polymerization of bio-based feedstock. However, post-consumer plastic films do not possess the same optical and energy properties as virgin polymers. The combined benefits of different polymers suggest that these materials could be adopted on a large scale over the long-term.

The construction sector, in modern times, is faced by a myriad of challenges primarily due to the increase in the urban population and dwindling natural resources that facilitate the production of construction materials. Furthermore, higher awareness on climate change is forcing companies to rethink their strategies in developing more sustainable construction materials. Diverse types of agro-waste ranging from rice husk ash (RHA), sugarcane bagasse ash (SCBA), and bamboo leaves ash (BLA) among others have been identified as potent solutions in the development of sustainable construction materials. In this review paper, six different construction materials, made using agro-waste products, are examined. The materials include brick/masonry elements, green concrete, insulation materials for buildings, reinforcement materials for buildings, particleboards, and bio-based plastics. The main criterion adopted in selecting the materials regards their popularity and wide-scale use in modern construction applications. Additionally, as this research emphasizes identifying alternative approaches to develop sustainable construction materials, the focus is directed toward mainstream materials whose continued use has an adverse impact on the environment. The findings obtained from the review showed that the use of agro-waste to develop sustainable construction materials was effective, as the developed materials adhered to established building standards. Therefore, this indicates that agro-waste materials have the potential to replace conventional construction materials and hence achieve economic, environmental, and social sustainability in the long run.

The aim of this paper is to present a detailed methodology for the three‐dimensional finite element analysis of asymmetric slim floor beams under fire conditions. A fully controlled solution process is suggested through a detailed step‐by‐step presentation of the simulation parameters incorporated into the model. Work has been carried out so that any asymmetric slim floor beam can be assessed using the same consistent method, which is validated against two reported fire tests. Time–temperature and time–vertical displacement curves are calculated for the appropriate comparisons with experimental results, which show that the proposed methodology can accurately predict the thermal and structural behaviour of such beams.

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