5TH International Congress on Technology - Engineering & Science - Kuala Lumpur - Malaysia (2018-02-01)

Preparation And Characterization Of Amino Acid – Modified Pvc Adsorbing Film For Methyl Red Removal

Polyvinyl chloride (PVC), as an available, low cost and formulating versatile polymer is widely used in different industries [1, 2]. Regarding to its good film forming properties, PVC is one of the most applicable polymers to prepare polymeric films such as nanocomposites and different kind of membranes, for many years [2]. However in the case of adsorbing films or adsorbing UF membranes, PVC was not be used lonely. Indeed there is no study which focused on the high adsorbing ability of PVC. Anyhow, it can be used as support of adsorbents which deposit on PVC film surface or inserted into its matrix. In most cases, nanoparticles are incorporated as adsorbent into polymer matrix and leads to the formation of nanocomposite films [3-5]. On the other hand, functionalization of polymer chains can also be conducted to improve adsorbing capacity of polymers such as PVC. In this case, appearing new functional groups provide surface properties to adsorb materials based on the physical or chemical mechanism. Acidification or applying functional polymers such as Tannin and amino acids are the most common methods to provide film polymer with an appropriate reaction sites or antifouling effects [5-7]. Amino acids include NH2 and COO- functional groups and thus they can be interact with positively or negatively charged solute and eliminate them from aqueous solution [5]. Accordingly the current study was focused on the effect of incorporation of one kind of amino acid in PVC matrix on adsorption performance of resultant polymeric film. For this purpose, Methionine as amino acid was inserted into polymer matrix using solution blending method. Accordingly, certain amount of Methionine was added to NMP/water solution and stirred for 1h then PVC was added to solution and stirred for 12h. After degassing, the resultant solution was cast on glass plate and immersed in water bath to form porous film. The resultant samples were nominated according to the Table 1. ATR-FTIR analysis was conducted to investigate the interaction between amino acid and polymer chains. Regarding to the FTIR spectra of modified PVC (Fig. 1), it is observed that the bands around 1600 cm-1 become broader and the bond correspond to COOH group became more intense (3400 cm-1 and 2900 cm-1). This implies that NH2 functional groups of methionine react with the C-Cl and form C-N bonds [8]. Therefore, it is expected that carboxylic groups of Methionine detect on PVC film and can be easily react with positively charged solutes during adsorption process. The adsorption capacity of resultant films was studied through removal of methyl red from aqueous solution at pH of 4. Methyl red as azo dye includes positive charges at acidic range of pH [9]. the adsorption experiments was performed at static conditions and results are presented in Fig2. According to the Fig.2 one can concluded that modification of PVC film can improved adsorption capacity of PVC and can be recommended as new formulation for preparation of adsorbing UF membranes.
Mahdieh Namvar-Mahboub, Amir Mohammad Ghadimi