Biocomposite materials have a significant function in saving the environment by replacing artificial plastic materials with natural substances. They have been enrolled in many applications, such as housing, automotive engine components, aerospace and military products, electronic and circuit board components, and oil and gas equipment. Therefore, continuous studies have been employed to improve their mechanical, thermal, physical properties. In this research, we conduct a comprehensive review about corn fiber and corn starch-based biocomposite. The results gained from previous studies were compared and discussed. Firstly, the chemical, thermal, and mechanical properties of cornstarch-based composite were discussed. Then, the effects of various types of plasticizers on the flexibility of the cornstarch-based composite were addressed. The effects of chemical treatments on the properties of biocomposite using different cross-linking agents were discussed. The corn fiber surface treatment to enhance interfacial adhesion between natural fiber and polymeric matrix also were addressed. Finally, morphological characterization, crystallinity degree, and measurement of vapor permeability, degradation, and uptake of water were discussed. The mechanical, thermal, and water resistance properties of corn starch and fibers-based biopolymers show a significant improvement through plasticizing, chemical treatment, grafting, and cross-linker agent procedures, which expands their potential applications.

In arid locations, global warming raises the indoor air temperature and energy utilization of residential and commercial buildings. Developing effective passive cooling solutions is critical for lowering room air temperatures and improving building energy consumption. The phase change materials (PCMs) based thermal energy storage (TES) roofing systems have received more attention in recent years due to their ability to decrease the energy consumption of the buildings. The PCMs were used in different ways, such as encapsulated PCM systems, free cooling applications, air-conditioning systems, and sorption cooling systems. The results of various studies have revealed that a decrease in indoor air temperature of approximately 1–3°C was obtained. Integration of PCMs with other cooling techniques may further improve the building cooling effects. The current study attempts to improve the cooling effect by integrating a PCM with a double-skin aluminium radiation reflector (ARR) in the summer seasons of an arid region like the Sultanate of Oman. Field investigations indicated that the double skin PCM-ARR cool roof room had a substantial drop in room air and roof surface temperatures than a standard bare concrete roof. The experimental investigation revealed that the room air, interior, and exterior roof surface temperatures of the double skin PCM-ARR roof model were reduced by 3.63°C (9.08%), 12.68°C (30.1%), and 16.92°C (37.3%) than the reference roof model, respectively. The corresponding average reduction in the heat flux was 18 W/m². The presence of dynamic air between PCM and ARR resulted in the roof’s superior thermal resistance (convective heat flux). The experimental research has shown that during the summer seasons, the double skin roof PCM-ARR substantially lowers temperatures of interior air and roof surface of buildings.

Indoor air temperatures and energy consumption of residential building is increasing at an alarming rate. The design and development of passive and hybrid roof cooling systems with effective cooling techniques play a vital role in improving the thermal performance especially in arid regions. This study investigates the energy efficiency of five laboratory models of double skin passive and hybrid roof cooling systems. A comparative study on the thermal performance of these five systems reveals a highest 14.5°C (41%) and 69^oC (79%) reduction in the room and roof surface temperature with double skinned evaporative cooling roof system with forced convection. Similarly, significant reduction in room air and roof surface temperatures are also observed with the other types of double skin passive and hybrid roof cooling systems in comparison with the reference system. The studies have conclusively proven that the double skin passive and hybrid roof cooling systems can appreciably reduce the indoor air and roof surface temperature of residential and commercial buildings.