Interior marking into oxo-biodegradable polyethylene shopping bags to assess the presence of pro-oxidant additive by using ATR-FTİR technique

Durmuş, Yasemin
The production and consumption of synthetic polymeric materials and relevant plastic items have been increasing dramatically in last 50 years. Polyethylene (PE) with high versatility (HDPE, LDPE, LLDPE etc) has easy processability, and good thermal stability, resulting in the greatest applicability. Green house covers, mulch films, shopping bags, garbage bags, bottles etc. are all produced from PE. PE based materials are used for a short period time -and often only once- and then discarded. Polyethylene biodegrades slowly, especially when it is deprived of sunlight. This causes environmental pollution. Because of its low mass and highly contaminated state after use, recycling of PE is economically unfeasible. The use of pro-oxidant chemicals in its matrix is the solution to the environmental problems PE causes. Since the degraded products are more easily metabolized by microorganisms. Prooxidants containing transition metals, particularly Fe3+ stearate, are widely used as additives. In this study, the purpose was to introduce a marking material into oxobiodegradable polyethylene shopping bags to assess the presence of pro-oxidant additives, by using the ATR-FTIR and FTIR. Three different polymer markers; nitrile rubber, polyamide 12 and thermoplastic polyurethane, were used for this purpose. Selected polymer markers were preferred for being compatible, nontoxic, nonvolatile, cheap and available. It is shown that if these markers are added properly into the PE, even at very low concentrations like 0.09% by mass, could be detected by ATR-FTIR and FTIR. The best of the markers is assumed be nitrile rubber because of its unit absorption at 2238 cm-1 of CN group. Also, for selected samples, mechanical testing and thermal analysis were carried out to observe the properties of the polymer matrix and is found to be not altered the mentioned properties