Energy efficient out-of-oven manufacturing of natural fibre composites with integrated sensing capabilities and improved water barrier properties

Tailored Out-of-Oven Energy Efficient Manufacturing of High-Performance Composites with Two-Stage Self-Regulating Heating via a Double Positive Temperature Coefficient Effect

“…Very recently, our group has conducted studies on the pyroresistive performance of conductive polymer composites (CPCs), leading to the development of reliable self-regulating heating performance which can be utilized for sustainable OoO curing with in situ temperature adjustment. − By employing a single-step positive temperature coefficient (PTC) effect, which involves a sharp increase in the electrical resistance of the CPC due to the polymer matrix thermal expansion at the switching temperature ( T sw ), the heating can be self-regulated without overheating due to the disconnection of conductive pathways. When the temperature drops below T sw , the polymer shrinks back, reconnecting the conductive pathways and resuming the heating with the temperature under control. , Compared to composites cured by traditional oven heating, OoO curing requires only a few percentages of energy consumption, which significantly contributes to the sustainable manufacturing of composite materials, , especially considering the growing demand of advanced composites. The integrated CPC layer used in OoO curing also can be utilized as an embedded smart surface layer, providing additional functions ranging from structural health monitoring to deicing, toward a multifunctional lightweight composite structure.…”

“…Very recently, our group has conducted studies on the pyroresistive performance of conductive polymer composites (CPCs), leading to the development of reliable self-regulating heating performance which can be utilized for sustainable OoO curing with in situ temperature adjustment. 22 − 27 By employing a single-step positive temperature coefficient (PTC) effect, which involves a sharp increase in the electrical resistance of the CPC due to the polymer matrix thermal expansion at the switching temperature ( T sw ), the heating can be self-regulated without overheating due to the disconnection of conductive pathways. When the temperature drops below T sw , the polymer shrinks back, reconnecting the conductive pathways and resuming the heating with the temperature under control.…”

“…When the temperature drops below T sw , the polymer shrinks back, reconnecting the conductive pathways and resuming the heating with the temperature under control. 25 , 27 Compared to composites cured by traditional oven heating, OoO curing requires only a few percentages of energy consumption, which significantly contributes to the sustainable manufacturing of composite materials, 22 , 27 especially considering the growing demand of advanced composites. The integrated CPC layer used in OoO curing also can be utilized as an embedded smart surface layer, providing additional functions ranging from structural health monitoring to deicing, toward a multifunctional lightweight composite structure.…”