Surfactant

A surfactant of formula (I):

• A-(L1)a-(CH2)b-(L2)c-X (I)
• wherein
• A is a perfluoropolyether, wherein said perfluoropolyether comprises a repeat unit of the formula -[CF(CF3)CF2O]m—, wherein m is an integer from 10 to 100;
• L1 is CONR′, wherein R′ is selected from H and C1-6 alkyl;
• a is 0 or 1;
• b is 0 or an integer between 1 and 10;
• L2 is a linking group;
• c is 0 or 1;
• and
• X is selected from:
• (a) any one of
• wherein R3 is selected from C1-6 alkyl, and (CH2)dO(CH2CH2O)eRx, wherein Rx is H or C1-6 alkyl, d is a positive integer from 2 to 6, and e is 0 or a positive integer from 1 to 100;
• R4 is selected from C1-6 alkyl;
• and W− is a counter ion;
• (b)-any one of
• wherein R1 and R2 are independently selected from C1-6 alky;
• R4 is selected from C1-6 alkyl;
• Z is —(CH2)rO(CH2CH2O)g(CH2)s—Y-(L2)c-(CH2)b-(L1)a-A, wherein r is a positive integer from 2 to 6, g is 0 or a positive integer, s is 0 or a positive integer from 2 to 6, Y is
• wherein R1 and R2 are independently selected from H and C1-6 alkyl;
• R4 is selected from C1-6 alkyl;
• and W− is a counter ion.