Mukesh Ambani has just taken over as the world's richest Indian, leaving behind LN Mittal. But like every other industry, his company, the world's No 1 polyester maker, is also going through the same rigours of any other manufacturer. NDTV has learnt that Reliance is about to shut a polypropylene cum co-polymer unit with an annual capacity of 30,000 tonnes located in the main plant at Baroda, once owned by IPCL.