טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
Ph.D Thesis
Ph.D StudentAriel Sluszny
SubjectSilane-Modified Polymer Films: Development, Characterization
and Performance as Pervaporation Membranes
DepartmentDepartment of Materials Science and Engineering
Supervisors Full Professor Silverstein Michael
Professor Emeritus Narkis Nava


Abstract

The potential toxicity of trace organic contaminants such as trihalomethanes in water has driven the development of techniques for their removal from potable water.  In pervaporation, an emerging technology, contaminants selectively pass through a dense membrane and into a vapor phase. In this research, novel membranes were prepared by modifying a commercial poly(vinyl chloride) (PVC) film with a vinyl organosilane, (g‑methacryloxypropyltrimethoxysilane, MPTS). The influence of the synthesis route on the membrane structure, properties and pervaporation performance was studied.  The membranes were characterized using Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), thermal analysis, gel content determination, scanning electron microscopy (SEM) and atomic force microscopy (AFM). The membranes’ interaction with liquids and their performance in the batch pervaporation of haloorganics from water were studied. Semi-interpenetrating polymer networks (semi-IPN) were synthesized when an initiator was used to promote the vinyl reaction before extensive hydrolysis and condensation took place. When there was no initiator, the hydrolysis and condensation were more extensive, yielding a phase separated morphology. The MPTS-modified PVC membranes were more resistant to haloorganics and exhibited better performance in batch pervaporation Than did PVC.  The membranes with the phase separated structure exhibited higher permeabilities and selectivities than the semi-IPN membranes.