Title of Talk

Controlling the Self-Assembled Nanostructures of Liquid Crystalline Block Copolymers

 

Abstract

Liquid crystalline polymers (LCPs) can be used as rod blocks to construct rod-coil or rod-rod block copolymers (BCPs). Among the LCPs studied in literatures, mesogen-jacketed liquid crystalline polymers (MJLCPs), a special class of LCPs, have attracted increasing interest in recent years. As proposed by Zhou et al., bulky pendants in MJLCPs are considered to be densely packed around the backbone and force the backbone to adopt an extended conformation. The rod length of an MJLCP can be tuned by the degree of polymerization, while the rod diameter can be altered by varying the chemical structure of the side chain. The bulk self-assembled nanostructures of liquid crystalline BCPs, which are composed of MJLCPs as the rod blocks and CO₂-philic polydimethlysiloxane (PDMS) as the flexible block, can be adjusted by temperature changes, liquid crystalline (LC) phase transitions of MJLCPs (Figure 1), and the selective swelling of PDMS by supercritical CO₂. And many order-order transitions can be induced.

Figure 1. Order-order transition of PDMS-b-PBPCS induced by the liquid crystalline phase transition of PBPCS.

 

References:

1. Leibler, L. Macromolecules 1980, 13, 1602.

2. Matsen, M. W.; Schick, M. Phys. Rev. Lett. 1994, 72, 2660.

3. Matsen, M. W.; Bates, F. S. Macromolecules 1996, 29, 1091.

4. Chen, X.-F.; Shen, Z.; Wan, X.-H.; Fan, X.-H.; Chen, E.-Q.; Zhou, Q.-F. Chem. Soc. Rev. 2010, 39, 3072.

Zhihao Shen, Associate Professor

 

College of Chemistry and Molecular Engineering

Peking University, Beijing, 100871, China

e-mail: zshen@pku.edu.cn

 

Profile. Zhihao Shen received a B.S. degree from Nanjing University in 1994. Then he earned a Ph.D. degree in Polymer Science from The University of Akron under the supervision of Prof. Stephen Z. D. Cheng in May 2001. After working as a postdoctoral researcher for several years in both academia and industry, he joined the College of Chemistry and Molecular Engineering at Peking University as an associate professor in October 2007. His main research interests are condensed matter physics of polymers, including design and characterization of liquid crystalline homopolymers and block copolymers, exploration of nanotemplates and nanofiltration membranes based on block copolymers. He has published more than 60 scientific papers in journals such as Macromolecules and Polymer Chemistry since joining Peking University.

 

Selected Publications

1. Shi, L.-Y.; Zhou, Y.; Fan, X.-H.; Shen, Z. Macromolecules 2013, 46, 5308.

2. Shi, L.-Y.; Hsieh, I.-F.; Zhou, Y.; Yu, X.; Tian, H.-J.; Pan, Y.; Fan, X.-H.; Shen, Z. Macromolecules 2012, 45, 9719.

3. Shi, L.-Y.; Shen, Z.; Fan, X.-H. Macromolecules 2011, 44, 2900.

4. Zhou, Q. H.; Zheng, J. K.; Shen, Z.; Fan, X. H.; Chen, X. F.; Zhou, Q. F. Macromolecules 2010, 43, 5637.

5. Xu, Y. D.; Yang, Q.; Shen, Z.; Chen, X. F.; Fan, X. H.; Zhou, Q. F. Macromolecules 2009, 42, 2542.