Lipocationic polymers and uses thereof

A polymer comprising a formula:

• wherein:
• X1 is alkyl(C≦18) or substituted alkyl(C≦18);
• X2 is hydrogen, alkyl(C≦18), or substituted alkyl(C≦18);
• R1 is -A-Z;
• wherein:
• A is an alkanediyl(C≦18) or substituted alkanediyl(C≦18);
• Z is —NR3R4;
• wherein:
• R3 and R4 are each independently selected from hydrogen, alkyl(C≦18), substituted alkyl(C≦18);
• or R3 and R4 are taken together and are alkanediyl(C≦18) or substituted alkanediyl(C≦18);
• R2 is alkyl(C≦24), alkenyl(C≦24), substituted alkyl(C≦24), or substituted alkenyl(C≦24);
• x and y are each independently 0, 1, 2, 3, 4, or 5;
• m and n are each independently an integer between 0 and 250, provided that at least one of m and n is greater than 1;
• and
• the repeating units defined by m and n are randomly distributed throughout the polymer;
• or a pharmaceutically acceptable salt thereof.