Facile Synthesis of Phosphorus-Free Biobased Epoxy Resin with Exceptional Flame Retardancy, Mechanical Properties, and Heat Resistance AITranslate

Basic Information:

DOI：https://doi.org/10.1021/acsapm.3c01928

Chinese Library Classification Number:

Citation Information:

Preparing biobased epoxy resins with intrinsic flame retardancy, excellent mechanical properties, and high heat resistance has the potential to be used in high heat and flame-retardant fields (e.g., aerospace industry, electrical, and electronic areas). However, seeking renewable epoxy resins with those goals is still challenging. In this work, we prepare a biobased epoxy precursor (PGE) derived from phloretin via a one-step epoxidizing reaction and then solidified by 4,4′-diaminodiphenyl sulfone (DDS) to obtain the target epoxy resin (PGE/DDS). The high molecular chain rigidness and char yield by in situ-generated Schiff bases combined with aromatic rings endow the PGE/DDS with high glass transition temperature (Tg up to ∼259.2 °C), excellent mechanical properties (i.e., Young’s modulus and hardness up to ∼5.41 and ∼0.35 GPa, respectively), and intrinsic flame retardancy. PGE/DDS resin passed V-0 rating in the underwriters laboratories-94 (UL-94) test with a limiting oxygen index (LOI) of 33.5% and significantly decreased the peak heat release rate (PHRR) and total heat release (THR) by 71.1 and 41.2%, respectively. Furthermore, the PGE/DDS resin exhibits enhanced dimensional stability due to its increased cross-linking density and additional antibacterial characteristics because of the in situ-generated Schiff bases. Our strategy will promote the facile preparation and application of biobased epoxy resins with high performance and versatile properties in high heat and flame-retardant fields.