Mahamuni,

Sorry, you did not describe plastics you wont to analyse.The plastic should be desintegated to very fine powder. Desintegration should be carried out at subzero temperatures /e.g. - 10oC/ to avoid oxidation and evaporation of phenolics. In general, you could extract phenolic compounds fom your sample via extraction with water/or better 95% ethanol/ containing 2% of NaOH.

After extraction evaporate /or freeze dry in case water solution of alkali was used/ and acidify the extract with smaller volume of acetic acid solution in ethanol to release the phenolics. Evaporate excess of the acid and dissolve your final concentrate /phenols/ in small amount of THF, DMF or other suitable solvent and analyse by HPLC....

Note: it would be correct to test different times of extraction an check the phenolics concentration using chromatography /time to reach maximum yield/.

R.S.

Thanks Prof. Solar. Indeed I need to analyse the residual content (free) of monomer/Plastisizer present in the polymer. In specific I need to study the Free BPA in different polymers as follows, PET, HDPE,LDPE, PS, SAN, PP and PVC. If you could direct me towards any available protocol in this regard, I would be thankful.

Thanks for the response,

I am sorry, my field of chemistry is very different of yours and so I cannot help you much. I prefer to give you the name of person that is following me on RG. His name is Prof. Juraj Ladomerský - you might contact him. He is head of Dept. of environmentalistics of Faculty of ecology and environmentalistic of Technical University in Zvolen. He may be skilled in recyling and analysing the chmicals /plasticizers, antioxidants ec./ you mentiond in your text.

Best regards,

R. Solár.

Dear Mahamuni Durai,

If you want extract the BPA from plastic polymers with the aim of performing migration studies, the directives (FDA, EmEA) impose to study the release of additives in different conditions. In litterature, the migration studies were performed with distilled water, distilled water with 3% acetic acid, distilled water with 10% ethanol, at 25°C, in autoclave, at 60°C...

In the framework of my PhD, I studied the release of different plastic polymers at room temperature, in autoclave, and this in different conditions of pH (water at pH2, water at pH 7, and water at pH9), and in different conditions of time (1 hour, 7 days, 1 month)

I hope I have helped you

Best regards

C.Pouech

Thanks for your interest to answer my query Prof. Pouech. I do have protocol(s) for study the migrated BPA from ploymers into food matrices. But I need protocols to quantify the residual (free) BPA present in the polymer. For polycarbonate (PC) plastic, 1g of polymer is dissolved with 20ml of dichloromethane (DCM) and then reprecipitated with methanol; while the free BPA is migrated to methanol, later quanified with HPLC (Biles, J. Eet al., Determination of bisphenol-A in reusable polycarbonate food contact plastics and migration to food-simulating liquids. J. Agric.

Food Chem., 1997, 45, 3541–3544.).

Now Can i have adopt this procedure for other polymers? But the thing is the solvents for diddollution and reprecipitation arediffer to various polymers.

Please Help me...

The studies dealing with the dissolution and reprecipitation of polymers that I have read have performed the dissolution step with toluene and the redisssolution step with methanol as for example :

- Polymer degradation and Stability 95 (2010) 740-745;

- Polymer Testing 32 (2013) 901-906;

- Chromatographia Vol.48 (1998) N°7-8;

- Journal of Supercritical Fluids 50 (2009) 22-28

- And, the authors of "Journal of Chromatography A 629 (1993) 283-293" have used chloroforme and ethyl acetate.

Best regards

C.Pouech

Thanks prof.Pouech. i am working on it. let me clarified later