Simultaneously improving the fire safety and mechanical properties of epoxy resin with iron phosphonated grafted polyethylenimine. (December 2022)

• Record Type: Journal Article
• Authors: Shi, Xiao-Hui; Liu, Qing-Yun; Li, Xue-Lin; Yang, Si-Yi; Wang, De-Yi
• Is Part Of: Polymer degradation and stability. Volume 206(2022)
• Publication Date: 2022-12
• Subjects: Hyperbranched flame retardant -- Iron phosphonated grafted polyethylenimine -- Epoxy resin -- Toughening; Polymers -- Deterioration -- Periodicals; Stabilizing agents -- Periodicals; Polymères -- Dégradation -- Périodiques; Stabilisants -- Périodiques; 668.9
• DOI: 10.1016/j.polymdegradstab.2022.110173
• Languages: English
• ISSNs: 0141-3910

Abstract

Highlights: A hyperbranched multifunctional additive (PEIP-Fe) for epoxy resin designed. The fire safety such as flame retardancy, smoke suppression and toxicity were all improved with 3 wt% of PEIP-Fe. Simultaneously, the impact strength, tensile strength, flexural strength and Tg of EP were all enhanced with 3 wt% of PEIP-Fe. Abstract: Endowing epoxy resins with enhanced flame retardancy, toughness and strength as well as glass transition temperature (Tg ) simultaneously is a big challenge in academia and industry fields. Herein, a hyperbranched multifunctional additive (PEIP-Fe) was designed, which was prepared through a Mannich condensation reaction of polyethyleneimine and phosphorous acid and followed by combining with ferric. When 3 wt% of PEIP-Fe was incorporated into epoxy resin, the impact strength, tensile strength, flexural strength and Tg were all enhanced due to the multiple toughening mechanisms, good compatibility and the increased cross-linking density. Simultaneously, fire safety such as flame retardancy, smoke suppression and toxicity were all improved. The flame-retardant mechanism was verified in both condensed-phase and gas-phase by catalytic charring and free radical scavenging, forming compact and continuous char layer and releasing phosphorus-containing species respectively. This work provides new thinking for the design of multifunctional and high efficiency additives for epoxy resin.