Polymer blend comprising fluorinated block copolyester

A polymer blend comprising a poly(alkylene arylate) and 0.1 to 10 weight percent based upon the total weight of the blend of a block copolymer having a blockiness index, B, in the range of 0.56 to 0.8, comprising a first block comprising a plurality of non-fluorinated alkylene arylate repeat units adjacent to one another;

• and a second block comprising a plurality of fluoroether functionalized alkylene arylate repeat units adjacent to one another;
• said non-fluorinated alkylene arylate repeat unit represented by Structure I
• wherein each R is independently H or C1-C10 alkyl, and R3 is C2-C4 alkylene which can be branched or unbranched;
• and, said fluoroether functionalized repeat units are represented by Structure II,
• wherein, Ar represents a benzene or naphthalene radical;
• each R is independently H, C1-C10 alkyl, C5-C15 aryl, C6-C20 arylalkyl;
• OH, or a radical represented by the Structure (III)
• with the proviso that only one R can be OH or the radical represented by the Structure (III);
• R1 is a C2-C4 alkylene radical which can be branched or unbranched,
• X is O or CF2;
• Z is H, Cl, or Br;
• a=0 or 1;
• and,
• Q represents the Structure (IIa)
• wherein q=0-10;
• Y is O or CF2;
• Rf1 is (CF2)n, wherein n is 0-10;
• and,
• Rf2 is (CF2)p, wherein p is 0-10, with the proviso that when p is 0, Y is CF2.