Asian propylene prices fell on Sept. 11, as weak demandpersisted.The Asian propylene market continued to grapple withsubdued demand from China on thin downstream productionmargins, while the weakness in upstream crude oil market led topoor buying sentiment among market participants.South Korean and Chinese buyers were facing sufficientstockpiles and were not looking to replenish their inventory now,a producer said.On the supply front, additional cargoes for September loadingwere heard from Southeast Asia, further lengthening the marketand increasing downward pressure on prices, sources said.Some market participants noted expectations of a temporaryprice support from the planned turnaround at GS Caltex's mixedfeedsteam cracker in late September.South Korea's GS Caltex plans to shut its mixed-feed steamcracker in Yeosu on Sept. 26 for 65 days of turnaround anddebottlenecking,CFR China propylene down $5/mt on the dayat $855/mt on Sept....