1. Beijing Advanced Innovation Center for Soft Matter Science and Engineering College of Materials Science and Engineering Beijing University of Chemical Technology Beijing 100029 China
2. Beijing Engineering Research Center for the Synthesis and Applications of Waterborne Polymers Beijing University of Chemical Technology Beijing 100029 China
3. Department of Polymer Science and Engineering University of Massachusetts Amherst Massachusetts 01003 USA
4. Materials Sciences Division Lawrence Berkeley National Laboratory 1 Cyclotron Road, Berkeley California 94720 USA