CATALYTIC DEGRADATION OF POLYSTYRENE. MODELING OF MOLECULAR WEIGHT DISTRIBUTION. EXPERIMENTAL VALIDATION

GIANOGLIO PANTANO, IOANA A.; DÍAZ, MÓNICA F.; ASTEASUAIN, MARIANO; BRANDOLIN, ADRIANA; SARMORIA, CLAUDIA

Los Cocos, Córdoba, Argentina

Simposio; V Argentine-Chilean Polymer Symposium; 2009

PLAPIQUI, INTEMA, INTEC, UNS, UNMDP, UNL, UNC

Reactive compatibilization of PE/PS blends is a recycling technique that may generate materials with suitable properties from waste streams. Compatibilization is reached through a Friedel-Crafts alkylation catalyzed by Aluminum chloride and styrene that produces a PS/PE graft copolymer. Under these conditions PS degradation takes place as a side reaction. Studies on the degradation of PS revealed that it is degraded when a strong Lewis acid such as Aluminum chloride is added. In this work, PS degradation is deeply studied as an initial step in the development of a mathematical model of the complete compatibilization reaction. Previously, we have modeled the effect of AlCl3 on PS, predicting accurately the PS average molecular weights during the reaction. However, it should be pointed out that final properties depend not only on average molecular weights but on the complete molecular weight distribution (MWD). Then, MDW evolution was predicted for PS degradation by means of a mathematical model where the mass balances were transformed using probability generating.In the present work we validate model results on MWD with experimental data obtained in our laboratory.