This work aims to provide an extensive evaluation on the use of polylactic acid (PLA) as a green, biodegradable thermal insulation material. The PLA was processed by melt extrusion followed by compression molding and then subjected to different annealing conditions. Afterwards, the thermal insulation properties and structural capacity of the PLA were characterized. Increasing the annealing time of PLA in the range of 0–24 h led to a considerable increase in the degree of crystallization, which had a direct impact on the thermal conductivity, density, and glass transition temperature. The thermal conductivity of PLA increased from 0.0643 W/(m·K) for quickly-cooled samples to 0.0904 W/(m·K) for the samples annealed for 24 h, while the glass transition temperature increased by approximately 11.33% to reach 59.0 °C. Moreover, the annealing process substantially improved the compressive strength and rigidity of the PLA and reduced its ductility. The results revealed that annealing PLA for 1–3 h at 90 °C produces an optimum thermal insulation material. The low thermal conductivity (0.0798–0.0865 W/(m·K)), low density (~1233 kg/m3), very low water retention (<0.19%) and high compressive strength (97.2–98.7 MPa) in this annealing time range are very promising to introduce PLA as a green insulation material.

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Benzamides were converted into benzonitriles with BrCCl 3 -PPh 3 -Et 3 N in CH 2 Cl 2 in an Appel-type reaction. Benzaldoximes could be transformed to benzonitriles under identical conditions. It was found that the reaction system BrCCl 3 -(2 equiv.)PPh 3 was also suitable for these transformations with PPh 3 replacing Et 3 N.

Heat transfer fluids (HTFs) are used widely in many industrial processes. They collect and transport thermal energy in process heating, metal working, machine cooling with applications in the aerospace, automotive, and marine industries. Also, these fluids comprise one of the key technological components in electricity generation from concentrating solar power systems (CSPs), where they can store thermal energy as a sensible heat reservoir for later delivery to the power conversion system in absence of solar radiation. In the current work, a new one pot strategy towards biarylated ethers as novel Heat Transfer Fluids, while using minimal amount of reaction solvent, has been developed.