2026-04-17T11:23:27Zhttps://recercat.cat/oai/request

oai:recercat.cat:2117/3289312026-01-15T06:11:01Zcom_2072_1033col_2072_452950

00925njm 22002777a 4500 dc Gamardella, Francesco author Flor López, Sílvia de la author Ramis Juan, Xavier author Serra Albet, Maria Àngels author 2020-06-01 Networked poly(thiourethane) materials with Tgs around 130 °C, derived from two aliphatic isocyanates (isophorone diisocyanate, IPDI and 4,4'-methylene bis(cyclohexyl isocyanate), HMDI) and one aromatic diisocyanate (toluene-2,4-diisocyanate, TDI) have been prepared with the same trithiol as comonomer (trimethylol propane tris(3-mercaptopropionate), S3) in stoichiometric proportions in the presence of dibutyltin dilaurate (DBTDL) as the catalyst. The higher reactivity of TDI allowed the preparation of this material in absence of catalyst. The evolution of the curing process has been followed by FTIR. Thermomechanical studies have been performed to determine their viscoelastic properties and their vitrimeric behaviour. The materials were able to reach a complete relaxation stress state thanks to the exchange process of the thiourethane moiety. Among them, TDI derived material experimented the fastest relaxation. The materials were also characterized by thermogravimetry and tensile tests. The recycled materials obtained by grinding the original thermosets and hot-pressing the powder have been fully characterized by mechanical, thermomechanical and FTIR studies, which allowed to confirm their recyclability without appreciable changes in the network structure. The presence of DBTDL in the materials has been proved to be necessary to reach a good recyclability. Postprint (author's final draft) Àrees temàtiques de la UPC::Enginyeria dels materials Àrees temàtiques de la UPC::Enginyeria química Heat resistant plastics Vitrimers Poly(thiourethane) Thermosets Recyclability Covalent adapatable networks Plàstics termostables Recyclable poly(thiourethane) vitrimers with high Tg. Influence of the isocyanate structure