Patent ID: 7816472

Claim:
A polymer prepared by a method comprising: providing an isocyanate-reactive component; providing a diacetylene-containing isocyanate-reactive component; providing an isocyanate-functional component; providing a reactive emulsifying compound; and optionally providing a catalyst; combining the isocyanate-reactive component, the diacetylene-containing component, the isocyanate-functional component, the reactive emulsifying compound, and the optional catalyst in an organic solvent and allowing them to react to form a diacetylene-containing polymer; and dispersing, and optionally chain extending, the diacetylene-containing polymer in a dispersing medium comprising water to form an aqueous dispersion comprising the diacetylene-containing polymer; wherein the diacetylene-containing polymer undergoes a color change upon irradiation to form a polydiacetylene-containing polymer; wherein the reactive emulsifying compound is represented by Formula (IV): wherein: G is selected from the group consisting of OH, NHR and SH; Q is a negatively charged moiety selected from COO − and SO 3 − , or a group that forms such a negatively charged moiety upon ionization; each of X, Y and R 1 may be the same or different; X, Y, R, and R 1 are independently selected from aliphatic organic radicals free of reactive functional groups having from about 1 to about 20 carbon atoms, and combinations thereof; R can be hydrogen; and R 1 is optional if Q is COO − and SO 3 − ; or the reactive emulsifying compound is represented by Formula (V): wherein: G is selected from the group consisting of OH, NHR and SH; each of X and Y may be the same or different; each of X and Y are independently selected from aliphatic organic radicals having from about 1 to about 20 carbon atoms, free of reactive functional groups, and combinations thereof; and R can be hydrogen or an aliphatic organic radical having from about 1 to about 20 carbon atoms, free of reactive functional groups.