The present invention relates to a method of fast curing a polythiourethane based transparent casted substrate. comprising in a preferred embodiment providing a first component A comprising a polythiourethane pre-polymer Al having isocyanate or isothiocyanate end groups. providing a second component B comprising a polythiourethane pre-polymer BI having thiol end groups. mixing together first and second components A and B and filling a molding cavity of a casting mold assembly with the resulting mixture. curing said mixture to obtain a transparent substrate, wherein at least one latent catalyst that is heat-activatable is added in the process prior to curing step 4). and said catalyst is subsequently activated to accelerate the polymerization reaction forming the polythiourethane based transparent substrate.

A vitrimerized polymer composition includes a polyurethane with partially broken down crosslinking ligands, a catalyst, and a dynamic recyclable network in which a portion of the catalyst forms ligands with a portion of the polyurethane.