title: Dramatically enhanced mechanical performance of nylon-6 magnetic composites with nanostructured hybrid one-dimensional carbon nanotube-two-dimensional clay nanoplatelet heterostructures.
abstract: Mechanically robust, magnetic nylon-6 nanocomposites reinforced by one-dimensional (1D) carbon nanotube (CNT)-two-dimensional (2D) clay nanoplatelet hybrids have been prepared using a simple melt-compounding technique. The direct iron-catalyzed chemical vapor deposition (CVD) growth of multiwalled CNTs utilizes iron oxide-immobilized clay nanoplatelets as substrates, carrying out in situ intercalation and exfoliation of clay nanoplatelets. By using such a hybridization and coexfoliation method, the as-obtained heterostructured hybrids used without any purification are demonstrated to be ideal and excellent nanofillers for mechanical reinforcement for fabricating nylon-6 nanocomposites, due to their homogeneous dispersion and strong interfacial interaction with the polymer matrix. The nucleation sites provided by the nanohybrids seem to be favorable to the formation of thermodynamically stable α-phase crystals of nylon-6 with much higher stiffness and hardness than γ-form of nylon-6, namely, a silicate-induced crystal transformation from the α-form to the γ-form of nylon-6 was greatly inhibited or "shielded" by the CNT-wrapped clay nanoplatelets. Furthermore, the nanostructured CNT-clay hybrid heterostructures containing residual iron oxide nanoparticles show novel magnetic properties in both bulk solids and polymer nanocomposites. Therefore, this can be probably developed into a facile and practical method to fabricate polymer nanocomposites with high performance and multifunctionality.
authors.affiliation: Key Laboratory of Molecular Engineering of Polymers of Ministry of Education, Department of Macromolecular Science, Fudan University, Shanghai 200433, P. R. China.
authors.forename: Chao
authors.initials: C
authors.lastname: Zhang
authors.forename: Weng Weei
authors.initials: WW
authors.lastname: Tjiu
authors.forename: Tianxi
authors.initials: T
authors.lastname: Liu
authors.forename: Wai Yi
authors.initials: WY
authors.lastname: Lui
authors.forename: In Yee
authors.initials: IY
authors.lastname: Phang
authors.forename: Wei-De
authors.initials: WD
authors.lastname: Zhang