Water-lock releasing chemical agent for oil and gas reservoirs, preparation method therefor and use thereof

A compound represented by the following formula (I):

• wherein, the second olefin oxide segment is selected from ethylene oxide, butylene oxide and styrene oxide;
• the total number of propylene oxide units in the propylene oxide segment is any integer of 1-40, preferably 2-20, more preferably 4-20, e.g. 8-20;
• the total number of second olefin oxide units in the second olefin oxide segment is any integer of 0-40, preferably 2-20, more preferably 4-20, e.g. 8-20;
• L is a linking group, for example C1-6 alkylene (e.g. —CH2— and —CH2CH2—), —CO—, —NH—;
• preferably, L is —CH2—;
• R is at least one of C1-C20 alkylene and a substituted C1-C20 alkylene, preferably, R is at least one of C1-C6 alkylene and a substituted C1-C6 alkylene;
• n is an integer of 1-20, preferably 4-12;
• x is any integer of 0-40, preferably 2-20, for example 4-20, e.g. 8-20;
• preferably, x is not 0;
• y is any integer of 0-40, preferably 2-20, for example 4-20, e.g. 8-20;
• X is one of —COOM, —SO3M, —OSO3M, and —OPO3M2, wherein M is a charge-balancing cation, M is preferably an alkali metal cation, an alkaline earth metal cation or an ammonium cation, more preferably Na+, K+ or NH4+.