Steady-State Optimization in a Continuous Emulsion Copolymerization of Styrene and Butadiene

VEGA, J.R.; GUGLIOTTA, L.M.; BRANDOLINI, M.C.; MEIRA, G.R.

LATIN AMERICAN APPLIED RESEARCH

PLAPIQUI(UNS-CONICET)

Lugar: Bahia Blanca; Año: 1995 vol. 25 p. 207 - 214

0327-0793

The production of styrene/butadiene rubber (SBR) in a train of continuous stirred-tank reactors (CSTR´s) is optimized, in the sense of improving its steady state (SS) productivity and product quality. The theoretical SS optimization is based on: a) the mathematical model of an industrial plant; b) the development of a specific algorithm, that feeds the monomer into the first reactor at a flow beloz that of particle saturation, to increase productivity; and c) novel expressions that allow to control the number average molecular weight (Mn) along the reaction train. In the normal SS operation, the complete recipe is fed into the first reactor. In the optimized SS, the monomers and the modifier are fed along the reactor train, while the total feed is increased to maintain the normal SS conversion. When exactly the same latex quality is required, then polymer production can be increased by around 6.5%. But by admitting slightly reduced particle diameters, then production increases of 30% or more can be achieved. Mn can be independently fixed along the train; or more generally, it can b e forced to follow any prespecified profile. the final product presents a reduced chemical composition drift, and similar values of polydispersity and degrees of branching.