Green Recycling of waste Optical Disc to Urethane Products

Abstract

<span style="font-size:11.0pt;font-family: " times="" new="" roman";mso-fareast-font-family:"times="" roman";mso-bidi-font-family:="" mangal;mso-ansi-language:en-gb;mso-fareast-language:en-us;mso-bidi-language:="" hi"="" lang="EN-GB">A new green recycling method of Polycarbonate (PC) plastic, from waste optical disks (ODs), to urethane products is proposed. Recycling involves the reaction of PC with glycol and urea at 180ºC under ammonia saturated condition. Optimum weight ratio (ethylene glycol to urea and PC) and time for recycling was decided with the help of sequential UV spectroscopic analysis at different weight ratios and time. IR spectroscopy evidences the presence of ethylene glycol carbamate (EGC) as active reaction intermediate. The resultant product mixture consists of following as the major reaction products: (<i>i</i>) BPA-C (Bisphenol A Carbamate; 4-[2-(4-hydroxyphenyl)propan-2-yl]phenyl carbamate) (40%); (<i>ii</i>) BPA-DC (Bisphenol A dicarbamate; propane-2,2-diyldibenzene-4,1-diyl dicarbamate) (45%) and ; (<i>iii</i>) BPA-CC (Bisphenol A carbamoylcarbamate; 4-{2-[4-(carbamoyloxy)phenyl]propan-2-yl}phenyl carbamoylcarbamate) (13%) as shown by LC-MS, NMR and elemental analysis. It is found that proposed process is 3.2 times more greener then the parallel process using process mass intensity (PMI) calculation. These products are found to be potent antimicrobial which can extend its application as material resources.</span>