Size-controlled self-assembly of anisotropic sepiolite fibers in rubber nanocomposites

作者：Di Credico Barbara^*; Cobani Elkid; Callone Emanuela; Conzatti Lucia; Cristofori Davide; D'Arienzo Massimiliano; Dire Sandra; Giannini Luca; Hanel Thomas; Scotti Roberto; Stagnaro Paola; Tadiello Luciano; Morazzoni Franca

来源：Applied Clay Science, 2018, 152: 51-64.

DOI：10.1016/j.clay.2017.10.032

• Sepiolite
• Rubber nanocomposite
• Self-assembly
• Organoclay
• Filler networking

The development of advanced polymer nanocomposites requires a strong filler-polymer interfacial interaction and an optimal filler nanodispersion. The incorporation of the clays into a polymer matrix frequently does not improve the composite mechanical properties, owing to both poor dispersion and macroscopic particle dimensions. In this work, pristine and organically-modified sepiolites (Sep) were structurally modified by an acid treatment, which provides nano-sized sepiolite (NS-Sep) fibers with reduced particle size and increased silanol groups on the surface layer. NS-Sep fibers were used to prepare styrene-butadiene rubber nanocomposites with enhanced mechanical properties.
Dynamic-mechanical analysis of clay polymer nanocomposites demonstrated that the NS-Sep fibers provided an excellent balance between reinforcing and hysteretic behavior, compared to the large-sized pristine Sep and isotropic silica. This was related to the enhanced interfacial chemical interaction between NS-Sep and rubber, as well as to the size and self-assembly of anisotropic nanofibers to form filler network structures, as supported by transmission electron microscopy analysis.
The preparation of nanocomposites, based on Sep nanofibers obtained by a simple and versatile acid treatment, can thus be considered an alternative approach for the designing of advanced clay polymer nano composites.

• 出版日期2018-2