Liquid-State and Solid-State Properties of Nanotube/Polypropylene Nanocomposites Elaborated via a Simple Procedure

Rheology of Polymer Processing in Spain (1995-2020)

The contribution of Spanish scientists to the rheology involved in polymer processing during the last 25 years is investigated. It is shown that the performed research covers, at different levels, all industrial polymeric materials: thermoplastics, thermosets, adhesives, biopolymers, composites and nanocomposites, and polymer modified bitumen. Therefore, the rheological behaviour of these materials in processing methods such as extrusion, injection moulding, additive manufacturing, and others is discussed, based on the literature results. A detailed view of the most outstanding achievements, based on the rheological criteria of the authors, is offered.

Mechanical and rheological properties of polystyrene-block-polybutadiene-block-polystyrene copolymer reinforced with carbon nanotubes: effect of processing conditions

Styrene-b-butadiene-b-styrene (SBS)-based nanocomposites filled with unmodified and –COOH functionalized carbon nanotubes (CNTs) have been formulated at different processing conditions in order to provide an understanding of the influence of the processing temperature and mixing speed on the nanofillers dispersion and on the overall properties of the nanocomposites. The evaluation of the nanocomposites’ mechanical and rheological behavior reveals that the effect of the processing speed on the final properties is almost negligible. Differently, the processing temperature influences strongly the mechanical and rheological properties of SBS-based nanocomposites. Indeed, for the nanocomposites formulated at high temperatures a significant enhancement of the overall properties with respect to the neat matrix has been achieved. Moreover, morphological analyses show that the state of dispersion of both unmodified and functionalized CNTs progressively improves as the processing temperature increases. Particularly, at low processing temperatures a segregated morphology in which the nanofillers are selectively confined in the domains of the SBS matrix has been obtained, while the nanocomposites formulated at 180°C show a homogeneous and uniform CNTs dispersion throughout the matrix and a strong level of interfacial adhesion between the copolymer chains and the dispersed nanofillers.