Solid polymer electrolyte and lithium secondary battery comprising same

A solid polymer electrolyte comprising a polymer including a first repeating unit represented by the following Chemical Formula 1:

• wherein, in Chemical Formula 1,
• R is hydrogen or an alkyl group having 1 to 3 carbon atoms;
• and
• a is an integer of any one of 1 to 800,
• wherein the polymer further includes at least one or more of a second repeating unit represented by the following Chemical Formula 2a and a third repeating unit represented by Chemical Formula 2b:
• in Chemical Formula 2a,
• R1 is hydrogen or an alkyl group having 1 to 3 carbon atoms;
• R2 and R3 are each independently an alkylene group having 1 to 3 carbon atoms;
• b is an integer of any one of 1 to 800;
• and
• o is an integer of any one of 10 to 100,
• in Chemical Formula 2b,
• R4 is or an alkyl group having 1 to 3 carbon atoms;
• R5 to R9 are each independently an alkylene group having 1 to 3 carbon atoms;
• c is an integer of any one of 1 to 800;
• and
• o1 to o4 are each independently an integer of any one of 1 to 120.