NEW NAVAL FILLERS FOR INDUSTRIAL APPLICATIONS IN THE YACHTING

In the Italian economy, the yachting field has a remarkable importance, indeed Italy is among the leading boat manufacturers both in Europe and in the world. The coatings for external surface of ships play a fundamental role, because they have to resist to aggressive environment and to thermal stresses respecting the Safety of Life at Sea rules and maintaining all the aesthetic properties typical of a luxury product (brightness, light reflection, their durability over time...). To respond to these demands the multi-coat systems are essential. They are protective systems based on the overlap of different layers with different thicknesses and aim, where the fundamental layer, from the mechanical point of view, is represented by the filler, a composite material with the first aim to fill the surface imperfections. The two-component fillers have been extensively studied in the present research project and they consist of one A component (based on epoxy resin) and one B component (the curing agent, based on polyamide); once mixed in opportune ratios they form the filler to apply. Being composite materials, in the two matrices are present several extenders (hollow glass microspheres, talc, carbonates...) and some additives (dispersants, rheological modifiers and anti-foam agents). In these composites several critical aspects are present and they are related both to the stability of the materials in the can (with respect to their rheology) and to the applied products (including the applications conditions, the mechanical properties and thermal stresses). This project was carried out in collaboration with Boero Bartolomeo SpA, one of the oldest paint factories in Europe, leader in Italy in paint building sector and leader in world for the yachting field, and for this reason, it was not possible to publish some details of the research work, due to confidentiality agreements. Targets of this research project are: the transition from empirical, typical of paint industry, to scientific knowledge in the formulation methodology, the optimisation of existing formulations and the development of a new filler for North European market, all this with particular attention to sustainability of the raw materials. Following the targets, this work, from a scientific point of view, permitted: 1) to deepen the knowledge of these materials, transforming traditional and empirical know-how, into scientific knowledge; 2) to carry out a systematic study of the raw materials, from the extenders to the additives, characterising them and observing their effects both on the single components and on the cross-linked products; 3) to better know the mechanism and time involved in the curing process, through infrared spectroscopy and calorimetric analysis, in different environmental conditions; 4) to treat rheological data with multivariate analysis. From an industrial point of view, the work permitted: 1) the better knowledge of the raw materials used; 2) the investigation of new raw materials, further introducing the company in the sustainable sector; 3) the development of the new filler that meets the requirements of a North European market.