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A series of triphenylamino (TPA)-chalcones and triphenylamino-β-arylchalcones, displaying either D-π-D or D-π-A architecture, were synthesized through aldol condensations and Heck reactions. The chalcone derivatives display intense absorption bands ranging from 389 to 432 nm and molar extinction coefficients of ca. 10 5 L mol-1 cm-1 corresponding to π-π* electronic transitions. The photoluminescence emissions are peaked between 470 and 563 nm with large Stokes shifts (80-131 nm), attributed to charge transfer in the excited state. The dyes present low fluorescence quantum yields, which is attributed to radiationless excited state deactivation related to aryl rings rotation. Spectroscopic and electrochemical methods were used to determine the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels. Both optical and electrochemical properties of the TPA-chalcone derivatives are considerably affected by the substitution pattern of the chalcones aryl rings and also by the β-arylation of the olefin moiety.

The synthetic rubber industry is of great importance and it is present in the daily life of world society. Butadiene rubber or polybutadiene is one of the most used polymers in this field, mainly in tire production. Therefore, the control of operational conditions and final properties of the polymer formed are important points to be studied as they are a challenge for the industry. Thus, the present work focus in simulate the batch polymerization of polybutadiene using the Aspen Plus software, where 1,3-butadiene, titanium tetrachloride, triethylaluminium, and hexane were used as monomer, catalyst, cocatalyst and solvent, respectively. Four cases were simulated changing the number of active catalyst sites in order to predict and compare the final properties of polybutadiene resins including the average molar masses, the molar mass distribution and the evolution of operation conditions that are used at plant to monitor the course of the reaction like the reaction temperature and pressure. The simulations show that three and four active catalyst sites are capable to synthesize polymers with similar properties than commercial and bench-scale polybutadienes.

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