PLASMA POLYMERIZATION OF STYRENE AND ACRYLIC ACID ON POLY(3-HYDROXYBUTYRATE) MEMBRANES FOR METHANOL/MTBE SEPARATION BY PV

MERCEDES VILLEGAS; ELZA F. CASTRO VIDAURRE; ALBERTO C. HABERT; JUAN C. GOTTIFREDI

Torun

Congreso; International Scientific Conference on Pervaporation, Vapor Permeation and Membrane Distillation; 2011

Nicolaus Copernicus University - Faculty of Chemistry NCU - Foundation Amicus

In this contribution, plasma polymerized styrene and acrylic acid on poly(3-hydroxybutyrate) (PHB) polymer films were evaluated as a suitable medium for methanol/MTBE separation by pervaporation (PV), and compared with previous investigations made with the virgin PHB membranes [1]. The substrate dense membranes were synthesized by solution-casting and the composite membranes where prepared in an inductively coupled radiofrequency (13.56MHz) plasma reactor. Experiments were performed at different powers (7.2 to 29.2W), using the polymerizable monomers mentioned, as well as mixtures of them with non polymerizable gases, such as argon and air. The depositions were also performed at different pressures in the reactor chamber (Figure 1). Depositions chemical characteristics were determined through FTIR spectroscopy, hydrophilic character and superficial energy through contact angle measurements, and SEM images were also taken to analyze the deposition morphology. Regarding PV measurements, the separation factor exceeded that of virgin membranes in all cases (Figure 1), reaching a maximum value of 19 for the acrylic acid polymerized at low pressure and power. Fluxes were lower than the original PHB membrane but the PSI were always higher. PV results were interpreted, discussed and linked to the others characterizations performed. [1] Villegas, M., Castro Vidaurre, E.F., Habert, A.C., Gottifredi, J.C., J. Membr. Sci. 367 (2011) 103.