Culture is abysmal, and this will take a long time to change.
The quality of middle management (the person who will probably be your boss) is sporadic at best. Lots of managers end up leading groups because they were good individual contributors, but they actually don't know the first thing about leading teams. I've worked for good, mediocre and absolutely horrible managers - and the horrible ones seem to do just fine at LYB because they have figured out how to blame their incompetence on the people working for them.
Bureaucracy and politics (especially between departments) makes this a frustrating place to work. Very little cooperation.
Lean structure plus moderately high turnover means that everyone is usually working at least two jobs.
Flat structure means your boss won't have much time to spend with you. This leads to management pretty much only interacting when mistakes are made - IE you should never expect someone to thank you for doing a good job.
