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An effective method was adopted to improve the thermo-mechanical properties of the epoxy composite by functionalization of the sisal fiber. Initially, a neat sisal fiber was acetylated with molar solution of acidic mixture (0.5:1 of HNO3:H2SO4) that removed the content of lignin and hemicellulose and increased the crystallinity of the sisal fiber. The acetylated sisal ( a-sisal) fiber was further treated with 3-aminpropyltriethoxy silane to graft the silanol moieties on sisal fiber. The functionalization of the sisal fiber with 3-aminpropyltriethoxy silane exhibits the strong interaction with epoxy, resulting in homogenous dispersion of the sisal fiber in epoxy. The composite possesses great enhancement in thermal and mechanical properties. The tensile strength in functionalized sisal epoxy composite ( CP-f-Sisal) was significantly enhanced up to 23% in comparison to non-functionalized sisal epoxy composite ( CP-n-Sisal) by adding 15 wt.% of the sisal fiber. In addition, the functionalized sisal epoxy composite ( CP-f-sisal) shows better thermal stability as compared to non-functionalized sisal epoxy composite ( CP-n-sisal). Similar results are attributed by investigating the kinetics of thermal stability parameters that include activation energy and integral procedure decomposition temperature.

This paper demonstrated the effect of functionalized magnesium oxide (MgO) nanoparticles with 3-(Aminopropyl) triethoxysilane (APTES) as llers on the mechanical and thermal properties of epoxy composite. The functionalization of MgO (S-MgO) considerably improved the inteface between the MgO and epoxy resin. The mechanical properties of the composites revealed that the addition of functionalized MgO improved their tensile strength, modulus of elasticity, and ductility when compared to neat epoxy. In compare to neat epoxy, the in-plane thermal conductivity of the epoxy composite with S-MgO ller improved by 10 folds. These observations indicated that the silane functionalization on MgO contributes to the formation of a strong interfacial bond and a compact interconnected network between the ller and the epoxy matrix.

The advancement in electronic device miniaturization has led to an increase in thermal issues. The reliability of these devices depends on heat dissipation, leading to the development of thermal interface materials (TIMs). In this study, the influence of morphology and surface modification on the thermal characteristics of magnesium oxide (MgO) incorporated epoxy composites was investigated. A wet precipitation method was employed for the synthesis of spherical S-MgO. However, oblong hexagonal H-MgO was obtained via a hydrothermal process. Fillers were functionalized with (3-Aminopropyl) triethoxysilane (APTES) to improve interfacial bonds. APTES modified oblong hexagonal MgO (AH-MgO) showed better thermal conductivity compared to APTES modified spherical MgO (AS-MgO). By the inclusion of 20 wt. % filler, the thermal conductivity of AH-MgO was enhanced ∼8.5 fold (1.88 W.m −1 .K −1 ) compared to neat epoxy (0.2 W.m −1 .K −1 ), which remains lower in AS-MgO ∼1.8 W.m −1 .K −1 (8 fold). AH-MgO-Epoxy exhibits improved thermal stability with an activation energy (Ea) of 98.10 KJ mol −1 in comparison to AS-MgO-Epoxy (90.56 KJ mol −1 ). The oblong hexagonal structure of AH-MgO facilitates more phonon transportation due to the elongated thermal conductive paths. Moreover, surface modification further advances interface with the epoxy matrix. The developed composite can be use as alternative TIMs for electronic packaging.

Agriculture residue is produced every year in millions of tons worldwide and can be used as cheaper and environmentally friendly adsorbent. Herein, the biochar was synthesized by pyrolysis from coconut hull, corncob, rice husk, peanut hull and wheat straw. Total organic carbon was determined by standard TC-IC method, i.e., for Wheat Straw was found 20% highest among others agricultural residue and selected for biochar/MnFe2O4 composite synthesis. FTIR spectroscopy showed a band at 630 cm−1 that confirms the presence of MnFe2O4. BET surface analysis data showed the average specific surface area of biochar in the range of (4.3–79.389 m2 g−1). The surface area of biochar/MnFe2O4 composite was 149.96 m2 g−1, which was highest of all synthesized biochar’s. Adsorption study was carried out by using a specified amount of biochar for the specified time in a 50 ml wastewater sample of known chemical oxygen demand (COD) value. Biochar/MnFe2O4 adsorbent composite showed greater COD reducing the capacity of 70% than that of biochar produced without the formation of precipitates of MnFe2O4. The combination of various appealing attributes including cost-effective, environmentally friendly, and good COD reducing ability makes adsorbent a good option to be used in industrial applications specifically in the field of water treatment.