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1630573 
Journal Article 
Modification of Tefzel film by Graft Copolymerization of Acrylonitrile and Methacrylonitrile for use as Membrane 
Kaur, I; Chauhan, GS; Misra, BN 
1998 
Yes 
Desalination
ISSN: 0011-9164 
Elsevier Science B.V., P.O. Box 211 Amsterdam 1000 AE Netherlands 
119 
1-3 (Sep 20 
359-360 
English 
WOS:000076265200055 
Tefzel a copolymer of ethylene and tetrafluorethylene with the repeat unit (CH sub(2)- CH sub(2)- CF sub(2)- CF sub(2)-) sub(n). It is a tough polymeric film with properties from both polyethylene and polytetrafluorethylene. Its use in various fields where functional groups are required is limited. In order to incorporate functional moieties to this polymeric backbone grafting of vinyl monomers such as Acrylonitrile (AN) and methacrylonitrile (MAN) has been attempted by preirradiation method, in aqueous medium. Optimum conditions for obtaining maximum percentage of grafting have been evaluated for both the monomers. Maximum grafting of AN (56.6%) and MAN (77.7%) is obtained at a total dose of 0.672 x 10 super(4) Gy and 0.576 x 10 super(4) Gy and [AN] = 3.018 moles/L and [MAN} = 1.177 moles/L using 100 ml of water. Effect of different alcohols such as methanol, ethanol, isopropanol, n-butanol, cyclohexanol on percentage grafting of AN and MAN has also been studied. It has been found that all the alcohols decreased percentage of grafting. Characterization of the Tefzel grafted films has been carried out by IR spectroscopic analysis which showed peaks at 2230 cm super(-1) due to grafted poly(Acrylonitrile) and poly (Methacrylonitrile) and thermogravimetric analysis. The primary thermograms of Tefzel film,, Tefzel-g-poly (AN) and Tefzel-g-poly(MAN) on comparison reveal that the grafted film becomes more thermally stable than the ungrafted Tefzel film. The initial decomposition temperature (IDT) of Tefzel film (392.3 degree C) is much less than the IDT of both AN and MAN grafted films i.e. (426.3 degree C) which is the same for both the grafted films. The final decomposition temperature (FDT) of Tefzel is also lower (501 degree C) continuing up to 681.6 degree C as compared to (512.3 degree C) for Tefzel-g-poly(AN) which continues up to 613.3 degree C and 511.4 degree C for Tefzel-g-poly(MAN) which continues up to 589.7 degree C. The total residue left behind is 0% in the case of Tefzel while for grafted films the residue left is 10% for AN grafted Tefzel film and 16% for MAN grafted Tefzel film. These observations indicate that upon grafting the film becomes thermally stable. The following plausible mechanism is proposed for grafting of AN and methcrylonitrile onto Tefzel film. The effect of all the reaction parameters such as total dose, monomer concentration, amount of water, reaction time etc. that effects the grafting reactions has been evaluated and the results are explained in the light of the proposed mechanism. 
Temperature; Membranes; Polymers; Optimization; Decomposition; Films; Alcohols; Infrared spectroscopy; 1998)