Low-dimensional carbonaceous nanofiller induced polymer crystallization

Low-dimensional carbonaceous nanofillers (LDCNs), i.e., fullerene, carbon nanofiber, carbon nanotube, and graphene, have emerged as a new class of functional nanomaterials world-wide due to their exceptional electrical, thermal, optical, and mechanical properties. One of the most promising applications of LDCNs is in polymer nanocomposites; these materials endow the polymer matrix with significant physical reinforcement and/or multi-functional capabilities. The relations between properties, structure and morphology of polymers in the nanocomposites offer an effective pathway to obtain novel and desired properties via structure manipulation, wherein the interfacial crystallization and the crystalline structure with the matrix are critical factors. By now, extensive studies have reported that LDCNs are highly effective nucleating agents that can significantly accelerate their crystallization kinetics and/or induce unique crystalline morphologies in nanocomposites. This review presents a thorough survey of the current literature on the issues relevant to LDCN-induced polymer crystallization. After a brief introduction to each type of LDCN and its derivatives, LDCN-induced crystallization kinetics with or without flow fields, crystalline modification, and interfacial crystalline morphologies are thoroughly reviewed. Then, the origins of LDCN-induced polymer crystallization are discussed in depth based on molecular simulation and experimental studies. Finally, an overview of the challenges in probing LDCN-induced polymer crystallization and the outlook for future developments in polymer/LDCN nanocomposites conclude this paper. Understanding LDCN-induced polymer crystallization offers a helpful guidance to purposefully regulate the structure and morphology, then achieving high-performance polymer/LDCN nanocomposites.