top of page

RESEARCH

Research Overview

(UPDATED 2021-09)

    We are a polymer physics research group located at USM's Polymer Science and Engineering department. Our research interest lies in various fundamental polymer physics phenomena related to conjugated polymers and their derivative devices. Specifically, we study structure, dynamics, and morphology of conjugated polymers and aim to link their molecular structures to their macroscopic properties (electronic, optical, mechanical) through advanced metrology with an emphasis on scattering techniques. Our long term goal to develop new material, and engineer new electronic devices to address the need in the energy, health and societal needs.

​

    Our group regularly use various large user facilities across the United States supported by DOE, as well as in-house X-ray beam line by Xenocs. 

​

Synchrotrons

 

Neutron sources

​

​

Previous Ph.D student thesis defense.

Dr. Song Zhang " Structural Origin Of Thermal, Mechanical Properties and Morphological Behaviors Of Semiconducting Polymers"

Link to thesis defense video, click here. 

​

Dr. Daniel Weller "Copolymer Microphase Separation, Properties, And applications"

Link to thesis defense video, click here. 

​

Dr. Luke Galuska "Thermomechanics of Semiconducting Polymers and Their Morphological Phenomena"

Link to thesis defense video, click here. 

​

Dr. Zhiqiang Cao "Understanding the Structure and Dynamics of Conjugated Polymers by Deuteration and Neutron Scattering"

Link to thesis defense video, click here. 

​

Dr. Nathaniel Prine "Using AFM-IR to Study Nanoscopic Phase Behavior of Polymer Blends and Photovoltaic Bulk Heterojunctions"

Link to thesis defense video, click here. 

​

Dr. Guorong Ma "Understanding Chain Dynamics and Conformation Of Conjugated Polymers In Films and Solutions"

Link to thesis defense video, click here. 

​

Dr. Sonia Stanciu "Enhancing Light Upconversion By Singlet-Sink-Type Triplet-Triplet Annihilation In Polymer Glasses"

Link to thesis defense video, click here.

​

Dr. Yunfei Wang "Development and Structural Origin Of Stretchable Semiconducting Polymers and Composites"

Link to thesis defense video, click here.

​

​

Screenshot 2023-09-27 at 1.46.38 PM.png

TOPIC 1: THIN-FILM MECHANICS FOR ELETRONICS

 

    We developed new multimodal metrology to understand the confinement effect on the conjugated polymeric film especially with the film thickness at 10s of nm scale. Conventionally, thin-film mechanics is challenging for any films below 10s of nm. Our group has developed a new methodology to probe thin-film mechanics on the supported liquid surface and free-standing film. Our team also proposed to use fracture energy as a better parameter to gauge the mechanical property of confined thin films. Combined with molecularly engineered polymers with systematically controlled building block variation, we aim to obtain fundamental new knowledge that could give new insights for future flexible and stretchable electronics. Our technique has been widely adopted by a wide range of researchers in the stretchable electronics community.  For more details, refer to our recent invited review article on thin-film characterization to highlight our contribution in this area.

​

Screenshot 2023-09-27 at 1.50.43 PM.png

TOPIC 2: POLYMER DYNAMICS FOR CONJUGATED POLYMER

​

     Dynamics concerns polymer chain movement in a wide range time and length scale. It is crucial to understand the stability of any organic electronic devices, as well as materials response to external stimuli such as mechanical or electrical. The dynamic property received much less attention compared to its optoelectronic property, despite its important role in device stability. Broadly speaking, our group is a leading team to develop a fundamental understanding of polymer dynamics using a wide range of characterization tools.   We use new metrology, fast scan DSCs, inelastic neutron scattering combined with molecular dynamos simulation, to study the design role that controls the chain dynamics for conjugated polymers.  We also work with theorist to develop method to predict, control the glass transition temperature for conjugated polymers. For more details, refer to our recent invited review article on glass transition temperature for conjugated polymers.

 

​

Screenshot 2023-09-27 at 1.46.25 PM.png

TOPIC 3: SINGLE CHAIN CONFORMATION FOR CONJUGATED POLYMER

        

   Although considerable progress has been made to optimize the optical and electronic properties of CPs, it remains a challenge to experimentally characterize conjugated backbone conformation (chain rigidity, planarity, and short-range order) and relate these to the optical and electronic properties (effective conjugation length, electronic coupling, etc.). This has left fundamental gaps in our knowledge of the most basic structure/property relationships within these systems, precluded the study of fundamental physical phenomena, and constrained the design and realization of new electronic materials and device functionalities. We aim to develop new methodologies to efficiently deuterate conjugated polymerS, understand the role of chain conformation, chain aggregation and how this impacts solid state optical, mechanical and electronic properties. We extensive use of neutron scattering and contrast variation techniques to probe single chain conformation. For more details, refer to our recent invited perspective article on the rigidity of the conjugated polymers.

 

 

Screenshot 2023-09-27 at 1.46.48 PM.png

Topic 4: NEW MORPHOLOGY CHARACTERIZATION CAPABILITY
   
      Our society is in constant need to develop new materials for new applications. Equally important is to develop characterization tools and techniques to study new materials. The ability to quantify the nanoscopic chemical information of polymeric materials is crucial for their structure-property relationship study. Our group used atomic force microscopy coupled with inferred laser. We aim to provide a synergistic characterization tool to couple inverse morphology characterization tools using scattering technique and real space tools from microscopy. Additionally, the ability to perform in situ or in operando characterization combine with X-ray or Neutron scattering enables precise understanding of morphology change at the molecular level. This also enables one to better design new advanced materials. Our group utilized in situ characterization capability at various DOE labs. 

Current Collaborators

  •   Derya Baran ( King Abdullah University of Science and Technology) - Doped polymer and thermoelectric

  •   Zhenan Bao (Stanford University) - Conjugated polymer synthesis and characterization 

  •   Yu-Cheng Chiu (National Taiwan University of Science and Technology) - Device fabrication  

  •   Lei Fang (Texas A&M University) - Conjugated polymer synthesis and characterization

  •   Christine Luscombe (Okinawa Institute of Science and Technology) - Conjugated polymer synthesis

  •   Boran Ma (University of Southern Mississippi) - Data science
  •   Jianguo Mei (Purdue University) - Conjugated polymer synthesis and characterization 

  •   Sarah Morgan (University of Southern Mississippi)   - Conjugated polymer characterization 

  •   Adam Moule ( University of California at Davis)  -  Inelastic scattering and DFT modeling

  •   Ting Lei (Peking University) - Conjugated polymer synthesis and characterization 

  •   Chad Risko (University of Kentucky) - Molecular dynamics simulation of functional polymers

  •   Simon Rondeau-Gagné (University of Windsor) - Conjugated polymer synthesis and characterization

  •   Bob Schroeder (University College London) - Conjugated polymer synthesis and characterization 

  •   Barry Thompson (University of Southern California) - Conjugated polymer synthesis and processing

  •   Wenjie Xia (Iowa State University) - Simulation of glass transition

  •   Jie Xu ( Argonne National Laboratory) - High throughput experiment

  •   Wei You (University of North Carolina at Chapel Hill) - Stable OPV materials and devices

​

Past Collaborators (within last 4 years)

  •    Jason Azoulay (University of Southern Mississippi)  - Conjugated polymer synthesis and characterization

  •    Kunlun Hong (Oak Ridge National Laboratory) -  Deuterated material synthesis and characterization 

  •   Robson Storey (University of Southern Mississippi)   - Elastomers synthesis and characterization

  •   Carlos Lopez-Barron (Exxon Mobile) - Elastomeric Material characterization 

  •   Dongshan Zhou (Nanjing University) - Glass transition

  •   Sergei Nazarenko (University of Southern Mississippi)   -  Membrane transportation

Current Supports

DOE BES

Neutron scattering program

Chemical and processing program

EPSOCR program

DOE user facility 

NSF

CHE- MSN program

DMR- POL program

OIA program

MRI program

AS-267478289059860_1440783201791_l.jpeg

ERDC 

Previous Supports

Exxon-Mobil

w5rnTVtV_400x400.jpg

ORAU

images (1).jpg

Qatar QNRF

Unknown-2.png

3M Inc

Office_of_Naval_Research_Official_Logo.png

ONR 

bottom of page