报告题目：Surfactants and Sensors Based on Polymer-Coated Nanoparticles

报 告 人：Prof. Bumjoon Kim （Korea Advanced Institute of Science and Technology (KAIST)）

报告时间：2014年11月26日下午3：00

报告地点：化学楼二楼一号会议室

Abstract:

        The mixing of polymers and NPs has opened pathways for engineering flexible composites that exhibit advantageous optical, electrical, magnetic and mechanical properties. We have developed a general scaffold for the design of novel functional nanomaterials from building blocks of polymer and inorganic particles and/or nanorods. The key role of our research involves the judicious selection of polymer shells to enhance the functionality of inorganic cores for their practical application, including their use as surfactants, thus creating new polymeric materials, sensors and organic electronics. Here I would like to introduce two examples of polymer-coated nanoparticles (NPs). In the first part of talk, I will discuss the size and shape effect of polymer coated NPs as a surfactant on the polymer blend system. We have developed a simple and powerful approach to fabricate a continuous conducting polymer film with an ultralow threshold that is based on Au NP surfactants. The addition of a very small amount of Au NPs dramatically reduced the volume fraction threshold for producing the conducting polymer film with high electrical and mechanical properties. In the second part of talk, I will introduce a powerful strategy of using size controlled Au NP surfactants to tailor both the external shape and internal nanoscale morphology of block copolymer (BCP) particles. The key to the successful generation of these novel structures is the use of size-controlled Au NPs, in which the relative size-ratio of Au NPs (d) over the Au NP-hosting domain (L), i.e., d/L, was critical for their precise positioning to determine their ability to function as surfactants in emulsions. The size-dependent assembly of Au NPs was preferentially localized at the interface between the P4VP domain at the surface of the particle and the surrounding water, which generated a balanced interfacial interaction between the two different PS/P4VP domains of the BCP particles and surrounding water, producing convex lens-shaped BCP particles.
Selected publication:

(1)   Kang, D.J. et al. ACS Nano 2011, 5, 9017.

(2)   Paek, K. et al. ACS Nano 2014, 3 2848.

(3)   Kim, H. J. et al. ACS Nano 2014, In Press.

(4)   Kim, Y. J. et al. J. Am. Chem. Soc. 2014, 136, 2767.
(5)   Ku, K. H. et al. J. Am. Chem. Soc. 2014, 136, 9982.