Patent 7316816 was granted and assigned to Agency for Science, Technology and Research on January, 2008 by the United States Patent and Trademark Office.
The invention is directed to a copolymer comprising at least three types of monomeric units, said three types of monomeric units comprising:a temperature-sensitive unit,a hydrophilic unit, anda hydrophobic unit comprising at least one pH-sensitive moiety;wherein said hydrophobic monomeric unit is derived from a copolymerisable unsaturated fatty acid.