...MEXICO CITY (S&P Global Ratings) Aug. 1, 2016--S&P Global Ratings said today that its ratings and outlook on Alpek S.A.B. de C.V. (###-/Stable/--) are not immediately affected following the company's announcement of a preliminary negotiations with Petroleo Brasileiro S.A. - Petrobras (B+/Negative/--) to acquire a 100% stake in the latter's Companhia Petroqufmica de Pernambuco (Petroqufmica Suape) and Companhia Integrada TOxtil de Pernambuco (Citepe). Alpek has 60-day exclusive negotiation period extendable to additional 30 days. The closing of the transaction is subject to further corporate, and the regulatory approvals. Given that the acquisition is still under negotiations and there are no details on the terms and conditions of this potential acquisition, it's too early to determine the impact of the transaction on the ratings. However, we will continue to monitor Alpek's key credit metrics, liquidity, and financial policy to be in line with its current strong liquidity and modest financial...