摘要
Fabricating a high-performing thermoset using bio-based flame retardant is critical for the sustain-able development of engineering materials with superior fire safety and robust mechanical properties.Herein,the epoxy(EP)composites with the industrial requirements are manufactured with a novel high-efficient,lignin-based flame retardant named DAL-x,which is fabricated by grafting 9,10-dihydro-9-oxa-10-phosphaze-10-oxide(DOPO)onto lignin.The resulting DAL-x/EP composite exhibits excellent flame retardancy with a desirable UL-94 V-0 rating and a satisfactory limiting oxygen index(LOI)of 29.8%due to the appropriate phosphorus content of DAL-x with adjustable molecular chain structure.More-over,the DAL-x/EP composite shows an unexpected improvement in the elastic modulus(∼36%)and well-preserved strength and ductility compared with those of pure EP.This work offers a feasible strat-egy for creating efficient bio-based flame retardants utilizing industrial waste lignin and preparing high-performance EP composites that meet the demanding requirement of fire retardancy in industries,con-tributing to the circular economy and sustainability.
基金
financially supported by the National Natural Science Foundation of China(Nos.51873196 and 51903222)
the Australian Research Council(Nos.LP220100278,DP190102992 and FT190100188)
the Natural Science Foundation of Zhejiang Province(No.LY21E030001)
the“Pioneer”and“Leading Goose”R&D Program of Zhejiang(No.2022C03128).