国内期货主力合约涨跌互现，20号胶（NR）、丁二烯橡胶涨超1%

Group 1 - The domestic futures market showed mixed results on October 15, with the main contracts experiencing both gains and losses [1] - Natural rubber (20号胶) and butadiene rubber saw increases of over 1% [1] - On the downside, styrene (苯乙烯), iron ore (铁矿石), pure benzene (纯苯), and soda ash (纯碱) all fell by more than 1%, while hot-rolled coil (热卷) dropped nearly 1% [1]