1,2-Propylene glycol 1-monobutyl ether 1-Butoxy-2-propanol 2-Hydroxy-3-butoxypropane 2-Propanol, 1-butoxy- 5131-66-8 NSC2211 Propylene glycol monobutyl ether WLN: QY1&1O4 n-Butoxypropanol