Prof. Enrico Boccaleri of the Università del Piemonte Orientale (Italy) presented the work done with Marco Milanesio, Luca Palin, Giuseppe Rombolà and Gianluca Sarti on ‘Functional nano-additives for the modification of the properties of p-PVC for cable applications’ at Cables 2018, held in Cologne in March.

Nanotechnologies represent an interesting perspective for the development and application of efficient functional additives in polymers.

Despite a restricted number of papers in literature, a comprehensive study of nano-additives in PVC, carried out by the researchers, demonstrates their suitability also for this matrix.

The study consisted in an exhaustive experimental work, which saw the participation of a pool of PVC producers and manufacturers and the strong collaboration with Nova Res S.r.l., a company born as an academic spin-off and expert in tailoring of the applications of new materials to industrial contexts.

The work considered the features provided by nanostructured materials applied to p-PVC with particular focus on cables. P-PVC nanocomposites have been developed using both laboratory and quality assessment/regulatory methods strating from a on typical cable formulation, using commercially available nano-additives and utilising industrial-grade pilot equipments.

The results show that positive effects at nanoscale level are evident even with a limited amount of additives (i.e. down to 0.3 phr) in several features, combining chemical effects on thermal stability, degradation and HCl evolution with improved or unmodified physical performances.

The study highlighted in fact several noteworthy features, due to the role of additives as:

• Active materials during polymer processing, reacting with the polymer during extrusion preventing degradation, or changing the melt flow properties widening the processing conditions.
• Reinforcing and/or stabilising agents, exploiting nano-level widespread and distributed interactions with the PVC matrix, promoting an improved durability and higher mechanical performances.
• Synergistic role, able to enhance and tune the efficacy of other (nano)additives, in particular for the thermal stabilization, the HCl release and the distribution of fillers at nanoscale level, reducing the amount needed to promote reinforcement effects.