Riduzione dell'impatto ambientale nella coagulazione del poliuretano in tessuti tecnici [Low environmental impact process for the coagulation of the polyurethane in technical fabrics]

In recent years, the use of multilayer textile products obtained by coating and coagulation of polyurethane polymers faced a growing interest in many markets due to the exceptional characteristics in terms of textile “hand” and appearance, similar to natural leather [1-3]. Typically, the synthetic leather production cycle uses a nitrogenous organic compound known as Dimethylformamide (DMF), as a natural solvent for polymers to be coated and coagulated in the outer layer. Since DMF, an organic compound with exact denomination N,N-Dimethylformamide QP (CH3) 2NOH, is a volatile compound characterized by acute toxicity, the manufacturing process has a strong environmental impact [4]. In 2004 the Italian normative assimilated a new European Directive enacting the regulation 44/04 VOC (volatile organic compounds) thus imposing the application of the European Council Directive 1999/13/EC of 11 March 1999 on the limitation of emissions of volatile organic compounds due to the use of organic solvents in certain activities and installations. The new rules limit the emission of DMF from mg/nm3 a 2 mg/ nm3. As a consequence, the plant costs to be sustained by SME for reducing DMF emission are considerably high, as well as disproportionate to the real quality improvement of the realized product. In order to confront this important issue, Tuscany Region (Italy) funded a project entitled “Research and Development of an innovative process for polyurethane coagulation characterized by low environmental impact”. The project aimed at developing an innovative process of coagulation of the polyurethane in aqueous solution in order to completely replace the conventional DMF based process. The project is managed by Manteco s.r.l. and the partners are Paola Textile Ltd. And SA-ME s.r.l. The innovative process is currently patented in Italy.