Active Materials and Additive Manufacturing Lab
 

Education

  • Sc.D., Massachusetts Institute of Technology, 2003
  • Ph.D.,Tsinghua University, China, 1999
  • B.S., Tsinghua University, China, 1994

Background

Dr. Qi joined Tech in January 2014 as an associate professor and was promoted to a full professor in March 2016. Prior, he was an associate professor at University of Colorado Boulder (2004-2013) and was a postdoctoral fellow at MIT (2003-2004). He is currently seeking talented undergraduate and PhD students and postdocs.

Research

  • Mechanics of Materials; Soft active materials; 3D/4D printing technology; 3D printing of active materials and structures; Design of active materials and structures; Recyclable polymer systems; Experimental characterization and constitutive modeling of nonlinear thermoviscoelastic behaviors of polymers; Polymer physics and mechanics; Photo-mechanics of light activated polymers; Shape memory polymers; Nonlinear finite element analysis; Mechanics of soft tissue growth.

Dr. Qi’s research falls in the general area of finite deformation multiphsyics modeling of soft active materials. The material systems include: shape memory polymers, shape memory elastomeric composites, light activated polymers, covalent adaptive network polymers (or vitrimers). Particularly, he is interested in understanding and modeling the evolution of material structure and mechanical properties of these materials under environmental stimuli, such as temperature, light, etc, and during material processing, such as 3D printing. To assist understanding of mechanical properties, his group routinely conducts thermomechanical or photo-mechanical experiments. Constitutive models developments are typically based on the observations from these experiments. The ultimate goal of the constitutive models is to integrate them with finite element through user material subroutines so that these models can be used to solve complicated 3D multiphysics problems involving nonlinear mechanics.

His current research projects include 4D printing of active materials, mechanics in 3D printing technology, active polymer design and manufacturing, reprocessing and recycling polymers. For 3D/4D printing, his group is developing 3D hybrid printing methods by using a variety of 3D printing technologies, such as inkjet, Stereolithography (SLA), Direct Ink Write (DiW), Fused Deposition Modeling (FDM), to print active and functional materials, such as shape memory polymers, liquid crystal elastomers, conductive polymers, epoxies, and cellulose nanocrystals. For reprocessing and recycling polymers, his group is developing methods and technologies to recycling thermosetting polymers and composites, such as fiber reinforced epoxy composites. These projects are conducted through supports by NSF and AFOSR, and through collaborations with Singapore University of Technology and Design (SUTD), and Air Force Research Laboratories (AFRL).

 

  • The ASME Warner T. Koiter Medal (2024)
  • Highly Cited Researcher by Clarivate (2024) (more 21000 citations based on Web of Science).
  • The T. H. H. Pian Award from International Conference on Computational & Experimental Engineering and Sciences (ICCES) (2024)
  • James R. Rice Medal, Society of Engineering Science (2023)
  • Gerhard Kanig Lecture by the Berlin-Brandenburg Association for Polymer Research (2019)
  • Sigma Xi Best Faculty Paper Award (2018)
  • ASME Fellow (2015)
  • The Woodruff Faculty Fellow (2015)
  • J. T. Oden Faculty Fellowship, UT Austin, (2012)
  • AFRL summer faculty fellowship (2010-2012)
  • Mechanical Engineering Outstanding Research Award (2009)
  • Mechanical Engineering Chair Faculty Fellow (2008)
  • NSF Career Award (2007)
  • Woodward Outstanding Mechanical Engineering Faculty (2006-2007)

Selected Publications

  • Yue, L., Su, Y.L., Li, M., Yu, L., Sun, X., Cho, J., Brettmann, B., Gutekunst, W.R., Ramprasad, R., Qi,  H.J., Chemical circularity in 3D printing with biobased Δ‐valerolactone, Advanced Materials, 2024, 36 (34), 2310040. https://doi.org/10.1002/adma.202310040
  • Yue, L., Su, Y.L., Li, M., Yu, L., Montgomery, S.M., Sun, X., Finn, M.G., Gutekunst, W.R., Ramprasad, R., Qi, H.J., One-Pot Synthesis of Depolymerizable δ-Lactone Based Vitrimers, Advanced Materials, 2023, 35 (29), 2300954. https://doi.org/10.1002/adma.202300954
  • Qi, H., Yu, K., Shi, Q., Kuang, X., Methods of Recycling and Reshaping Thermosetting Polymers and Composites Thereof, US 11,421,095 B2 (08/2022).
  • Qi, H., Yu, K., Shi, Q., Methods of Recycling and Reshaping Thermosetting Polymers and Composites Thereof, US 10,829,612 B2 (11/2020).
  • Yu, K., Shi, Q., Dunn, M.L., Wang, T., Qi, H.J., Carbon fiber reinforced thermoset composite with near 100% recyclability, Advanced Functional Materials, 2016, 26 (33), 6098-6106. https://doi.org/10.1002/adfm.201602056
  • Kuang, X., Zhou, Y., Shi, Q., Wang, T., Qi, H.J., Recycling of epoxy thermoset and composites via good solvent assisted and small molecules participated exchange reactions, ACS Sustainable Chemistry & Engineering, 2018, 6 (7), 9189-9197. https://doi.org/10.1021/acssuschemeng.8b01538
  • Yu, K., Taynton, P., Zhang, W., Dunn, M.L., Qi, H.J., Reprocessing and recycling of thermosetting polymers based on bond exchange reactions, RSC Advances, 2014, 4 (20), 10108-10117. https://doi.org/10.1039/C3RA47438K
  • Ryu, J., D’Amato, M., Cui, X., Long, K.N., Qi, H.J., Dunn, M.L., Photo-origami—bending and folding polymers with light, Applied Physics Letters, 2012, 100, 161908. https://doi.org/10.1063/1.3700719
  • Long, K.N., Scott, T.F., Qi, H.J., Bowman, C.N., Dunn, M.L., Photomechanics of light-activated polymers, Journal of the Mechanics and Physics of Solids, 2009, 57 (7), 1103-1121. https://doi.org/10.1016/j.jmps.2009.03.003
  • Yue, L., Montgomery, S.M., Sun, X., Yu, L., Song, Y., Nomura, T. Tanaka, M., Qi, H.J., Single-vat single-cure grayscale digital light processing 3D printing of materials with large property difference and high stretchability, Nature Communications, 2023, 14 (1), 1251. https://doi.org/10.1038/s41467-023-36909-y
  • Kuang, X., Wu, J., Chen, K., Zhao, Z., Ding, Z., Hu, F., Fang, D., Qi, H.J., Grayscale digital light processing 3D printing for highly functionally graded materials, Science Advances, 2019, 5 (5), eaav5790. https://doi.org/10.1126/sciadv.aav5790
  • Roach, D.J., Sun, X., Peng, X., Demoly, F., Zhou, K., Qi, H.J., 4D Printed Multifunctional Composites With Cooling‐Rate Mediated Tunable Shape Morphing, Advanced Functional Materials , 2022, 32 (36), 2203236. https://doi.org/10.1002/adfm.202203236
  • Peng, X., Wu, S., Sun, X., Yue, L., Montgomery, S.M., Demoly, F., Zhou, K., Zhao, R.R., Qi, H.J., 4D printing of freestanding liquid crystal elastomers via hybrid additive manufacturing, Advanced Materials, 2022, 34 (39), 2204890. https://doi.org/10.1002/adma.202204890
  • Peng, X., Kuang, X., Roach, D.J., Wang, Y., Hamel, C.M., Lu, C., Qi, H.J., Integrating digital light processing with direct ink writing for hybrid 3D printing of functional structures and devices, Additive Manufacturing, 2021, 40, 101911. https://doi.org/10.1016/j.addma.2021.101911
  • Roach, D., Hamel, C.M., Dunn, C.K., Johnson, M.V., Kuang, K., Qi, H.J., The m4 3D printer: A multi-material multi-method additive manufacturing platform for future 3D printed structures, Additive Manufacturing, 2019, 29, 100819. https://doi.org/10.1016/j.addma.2019.100819
  • Yuan, C., Roach, D.J., Dunn, C.K., Mu, Q., Kuang, X., Yakacki, C.M., Wang, T.J, Yu, K., Qi, H.J., 3D printed reversible shape changing soft actuators assisted by liquid crystal elastomers, Soft Matter, 2017, 13 (33), 5558-5568. https://doi.org/10.1039/C7SM00759K
  • Wu, J, Zhao, Z., Hamel, C.M., Mu, X., Kuang, X., Guo, Z., Qi, H.J., Evolution of material properties during free radical photopolymerization, Journal of the Mechanics and Physics of Solids, 2018, 112, 25-49. https://doi.org/10.1016/j.jmps.2017.11.018
  • Nguyen, T.D., Qi, H.J., Castro, F., Long, K.N., A thermoviscoelastic model for amorphous shape memory polymers: incorporating structural and stress relaxation, Journal of the Mechanics and Physics of Solids, 2008, 56 (9), 2792-2814. https://doi.org/10.1016/j.jmps.2008.04.007
  • Qi, H.J., Nguyen, T.D., Castro, F., Yakacki, C.M., Shandas, R., Finite deformation thermo-mechanical behavior of thermally induced shape memory polymers, Journal of the Mechanics and Physics of Solids, 2008, 56 (5), 1730-1751. https://doi.org/10.1016/j.jmps.2007.12.002
  • Qi, H.J., Boyce, M.C., Stress–strain behavior of thermoplastic polyurethanes, Mechanics of Materials, 2005, 37 (8), 817-839. https://doi.org/10.1016/j.mechmat.2004.08.001
  • Westbrook, K.K., Parakh, V., Chung, T., Mather, P.T., Wan, L.C., Dunn, M.L., Qi, H.J., Constitutive modeling of shape memory effects in semicrystalline polymers with stretch induced crystallization, Journal of Engineering Materials and Technology, 2010, 132(4): 041010. https://doi.org/10.1115/1.4001964
  • Taynton, P., Ni, H., Zhu, C., Yu, Y., Loob, S., Jin, Y., Qi, H.J., Zhang, W., Repairable woven carbon fiber composites with full recyclability enabled by malleable polyimine networks, Advanced Materials, 2016 28 (15), 2904-2909. https://doi.org/10.1002/adma.201505245
  • Taynton, P., Yu, K., Shoemaker, R.K., Jin, Y., Qi, H.J., Zhang, W., Water-driven malleability in a highly recyclable covalent network polymer, Advanced Materials, 2014, 26(23), 3938-3942. https://doi.org/10.1002/adma.201400317
  • Ge, Q., Qi, H.J., Dunn, M.L., Active materials by four-dimension printing, Applied Physics Letters, 2013, 103, 131901. https://doi.org/10.1063/1.4819837