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Decolorization of hydroxy-containing methacrylate homopolymers and copolymers

  • US 5,750,772 A
  • Filed: 01/30/1997
  • Issued: 05/12/1998
  • Est. Priority Date: 01/30/1997
  • Status: Expired due to Fees
First Claim
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1. A process for decolorizing homo- and co-polymers of hydroxy-containing methacrylates of the formula ##STR2## wherein n>

  • 2,m>

    4 and b>

    1;

    wherein said homo- and co-polymers are prepared in the presence of a chain transfer catalyst;

    comprising the steps of exposing the polymers to;

    (a) an acid having a pKa less than about 2;

    (b) a chelating bidentate nitrogen ligand containing a fragment of the formula alkylidene(NR2)x (imidazolyl)ywherein y>

    1 and (y+x)>

    2;

    said alkylidene is C2 to C10 ;

    each R is independently H or C1 to C10 alkyl;

    and(c) a polar absorbent medium.

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