Abstract
The potential prospect of expandable graphite (EG) in the development of polymer composites is severely limited by required large additions and poor interface compatibility with the polymer. Inspired by mussels, polydopamine (PDA) can be used as an effective interface modifier for EG to prepare ultra high molecular weight polyethylene (UHMWPE) composites with superior mechanical properties and high flame retardancy. The surface of expandable graphite (EG) was coated with a thin adhesive PDA film through self-polymerization of dopamine. The modified expandable graphite (EG@PDA) was combined with APP to prepare UHMWPE flame retardant composites. Compared with UHMWPE/APP/EG (with 20 wt% APP/EG), UHMWPE/APP/EG@PDA (with 20 wt% APP/EG@PDA) gives a decrement by 16.7% in limiting oxygen index, 29.7% in the peak of the heat release rate, 20.4% in total heat release and 49.3% in total smoke release, with an increment by 37% in tensile strength and 67.9% in elongation at break, respectively. It is suggested that the presence of PDA as an interface modifier can greatly improve the interfacial compatibility between EG and UHMWPE. Moreover, it can lead to forming more char residue and reducing the release of smoke particulates during combustion of the composites.
Highlights
With the wide application of ame-retardant composite materials, researchers are paying more and more attention to the mechanical properties of materials while pursuing ame retardant properties.[1]
The thermal stability, ammability and mechanical properties of Ultra-high-molecular-weight polyethylene (UHMWPE)/ammonium polyphosphate (APP)/expandable graphite (EG)@PDA were investigated by thermogravimetry analysis (TGA), limiting oxygen index (LOI) determination, vertical burning test (UL-94), cone calorimeter test (CCT) and tensile test, respectively
It is suggested that the surface of EG@PDA covered by polydopamine which formed by selfpolymerization of dopamine
Summary
With the wide application of ame-retardant composite materials, researchers are paying more and more attention to the mechanical properties of materials while pursuing ame retardant properties.[1]. Polydopamine (PDA) is a mussel-inspired bio-polymer which was discovered by Lee et al in 2007.14 Mussels can strongly attach to diverse substrates with high binding strength, even on wet surfaces. This phenomenon can be explained by the presence of PDA. Paper of EG and providing the composites excellent mechanical properties and ame retardancy Considering all of those aspects, PDA is used as a novel interface modi er to coat onto the surface of EG. A er the introduction of EG@PDA into UHMWPE/ APP, its mechanical properties, ame retardancy and smoke suppression of UHMWPE composites could be effectively enhanced. The thermal stability, ammability and mechanical properties of UHMWPE/APP/EG@PDA were investigated by thermogravimetry analysis (TGA), limiting oxygen index (LOI) determination, vertical burning test (UL-94), cone calorimeter test (CCT) and tensile test, respectively
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
