Development and characterization of fully bio‐based polybenzoxazine‐silica hybrid composites for low‐k and flame‐retardant applications

Abstract

In the present work, new classes of bio‐based polybenzoxazines were synthesized using eugenol as phenol source and furfurylamine and stearylamine as amine sources separately through solventless green synthetic process routes and were further reinforced with varying percentages (1, 3, 5, and 10 wt%) of silica (from rice husk) to attain hybrid composites. The molecular structure, cure behaviour, thermal stability, dielectric properties, and flame‐retardant behaviour of both benzoxazine monomers and benzoxazine composites were characterized using appropriate modern analytical techniques. The eugenol‐based benzoxazines synthesized using furfurylamine (FBz) and stearylamine (SBz) were cured at 223°C and 233°C, respectively. The differential scanning calorimetry (DSC) data reveal the glass transition temperatures (Tg) of FBz and SBz were 157°C and 132°C, respectively, and the maximum decomposition temperature (Tmax) as obtained from thermogravimetric analysis (TGA), were found to be 464°C and 398°C for FBz and SBz, respectively. The dielectric constants for FBz and SBz obtained at 1 MHz were 3.28 and 3.62, respectively. Furthermore, varying weight percentages (1, 3, 5, and 10 wt%) of 3‐mercaptopropyltrimethoxysilane (3‐MPTMS) functionalized bio‐silica reinforced the composite materials as evidenced by their improved thermal stability and lower dielectric constant. Data obtained from thermal and dielectric studies suggested that these polybenzoxazines could be used in the form of adhesives, sealants, and composites for high performance inter‐layer low‐k dielectric applications in microelectronics.

Hybrid Conversion of5‐Hydroxymethylfurfural to5‐Aminomethyl‐2‐furancarboxylic acid: Toward New Bio‐sourced Polymers

“…In total, 15 heterogeneous metal catalysts were screened on 1 a at small scale (1 mL), in glass sealed vials, to limit evaporation. The tested catalysts, which were selected according to their ability and versatility to oxidize short‐chain alcohols are listed in Table 1 [28b,37] …”

Eco-Friendly Sustainable Poly(benzoxazine-co-urethane) with Room-Temperature-Assisted Self-Healing Based on Supramolecular Interactions

“…The appearance of a vibration band at 960 cm –1 corresponds to the oxazine ring, which confirms the formation of the benzoxazine ring. 19 , 29 , 30 In the oxazine ring, the C–H out-of-plane bending is observed at 728 cm –1 . The vibration peaks around 1055–1118 cm –1 represent the symmetric stretching of C–O–C, and the peak at 1243 cm –1 represents the asymmetric stretching of C–O–C; also, the peak at 1355 cm –1 represents the C–N–C vibration.…”

Recent Advances in Flame Retardant Bio-Based Benzoxazine Resins

“…When synthesizing benzoxazine monomers, phosphorus-containing groups like DOPO can also be introduced to further enhance the flame retardancy of the monomers [59]. Furthermore, some silicon-containing monomers can also be introduced into benzoxazine monomers to prepare some composite material with better properties such as low water absorption, excellent mechanical property, flame retardancy, and so on [18,60,61]. Lin et al [38] achieved high-performance bio-based benzoxazines from renewable materials like furfurylamine and vanillin-derived biphenol (Fig.…”