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Monofilament composites of Co-continuous Polyamide12/Poly (Methyl Methacrylate)...

Polymer-polymer/carbon nanotube (CNT) composite fibres with a co-continuous morphology were developed, aiming at structural and functional applications. The objective was to produce fibres with electrical conductivity, provided by the incorporation of CNT, maintaining the mechanical properties at a level that allowed typical textile processing. If this goal is achieved, then the fibres may be incorporated into ...

The role of disorder on the AC and DC electrical conductivity of vapour grown c...

Four dispersion methods were used for the preparation of vapour grown carbon nanofibre (VGCNF)/epoxy composites. It is shown that each method induces certain levels of VGCNF dispersion and distribution within the matrix, and that these have a strong influence on the composite electrical properties. A homogenous VGCNF dispersion does not necessarily imply higher electrical conductivity. In fact, it is concluded ...

Multi-objective ant colony optimization for the twin-screw configuration problem

The Twin-Screw Configuration Problem (TSCP) consists in identifying the best location of a set of available screw elements along a screw shaft. Due to its combinatorial nature, it can be seen as a sequencing problem. In addition, different conflicting objectives may have to be considered when defining a screw configuration and, thus, it is usually tackled as a multi-objective optimization problem. In this resea...

Dispersion of carbon nanotubes in poly(lactic acid)

Carbon nanotubes (CNT) grow as entangled bundles that are difficult to disperse in polymer matrices, or even in solvents. However, their dispersion level in the polymer matrix strongly affects the final nanocomposite properties1. Previous studies have shown that filler dispersion can be assisted by the functionalization of the CNTs2. In the present work, CNTs were chemically functionalized to bond pyrrolidine g...

Study of solids conveying in single screw extruders based on flow dynamics and ...

Flow of granular matter is presently a subject of extensive research, due to the characteristics of this type of systems (e.g., dilatancy, segregation, arching, clustering) and relevance to various application areas, such as civil construction, agriculture, food processing, geophysics, pharmacology [1, 2]. The plasticating process in single screw polymer extrusion is one of the areas where this research can hel...

Near-infrared spectroscopy for on-line monitoring of nanoclay dispersion in pol...

A comparative study of the dispersion of carbon nanofibres in polymer melts

The dispersion of carbon nanofibres (CNF) in a polymer matrix using two melt mixing methods is studied. Distributive and dispersive mixing were evaluated by optical and electron microscopy. The CNF were chemically modified to improve the interface with the matrix. The results showed that the two methods produced good distribution of the filler, but extensional stresses induced higher dispersion. The latter corr...

Dispersion of carbon nanotubes in poly(lactic acid)

Carbon nanotubes (CNT) present excellent mechanical, electrical and thermal properties, and are expected to impart these properties into their composites. However, the CNT are grown as entangled bundles that are difficult to disperse in polymer matrices, or even in solvents. Several approaches have been tried for the efficient dispersion of CNT in polymer matrices, ranging from the CNT chemical modification to ...

Monofilament composites with carbon nanotubes for textile sensor applications

The aim of this work was to develop polymer matrix/carbon nanotube composite monofilaments to incorporate in textile products, to be used as sensors. The carbon nanotube polymer composite (CPC) monofilaments were produced with the required electrical and mechanical properties for the development of a textile sensor of water vapor. The monofilaments selected were formed by polylactic acid (PLA), and were incorpo...

Estimating the sustainability of carbon nanotube composites: reprocessing studies

Polylactide (PLA) has attracted particular attention in the area of environmentally degradable polymer materials. Some applications require the incorporation of a reinforcement material to produce a composite with specific properties. It was observed that PLA /carbon nanotube (CNT) composites present adequate properties for liquid sensing. The health risks involved in the use of carbon nanotubes are still unde...