1
|
Zhang J, Lei J, Feng P, Floudas G, Zhang G, Zhou J. Capillary filling of star polymer melts in nanopores. J Chem Phys 2024; 160:054903. [PMID: 38341697 DOI: 10.1063/5.0188955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2023] [Accepted: 01/15/2024] [Indexed: 02/13/2024] Open
Abstract
The topology of a polymer profoundly influences its behavior. However, its effect on imbibition dynamics remains poorly understood. In the present work, capillary filling (during imbibition and following full imbibition) of star polymer melts was investigated by molecular dynamics simulations with a coarse-grained model. The reversal of imbibition dynamics observed for linear-chain systems was also present for star polymers. Star polymers with short arms penetrate slower than the prediction of the Lucas-Washburn equation, while systems with long arms penetrate faster. The radius of gyration increases during confined flow, indicating the orientation and disentanglement of arms. In addition, the higher the functionality of the star polymer, the more entanglement points are retained. Besides, a stiff region near the core segments of the stars is observed, which increases in size with functionality. The proportion of different configurations of the arms (e.g., loops, trains, tails) changes dramatically with the arm length and degree of confinement but is only influenced by the functionality when the arms are short. Following full imbibition, the different decay rates of the self-correlation function of the core-to-end vector illustrate that arms take a longer time to reach the equilibrium state as the functionality, arm length, and degree of confinement increase, in agreement with recent experimental findings. Furthermore, the star topology induces a stronger effect of adsorption and friction, which becomes more pronounced with increasing functionality.
Collapse
Affiliation(s)
- Jianwei Zhang
- Faculty of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China
| | - Jinyu Lei
- Faculty of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China
| | - Pu Feng
- School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510640, China
| | - George Floudas
- Max Planck Institute for Polymer Research, 55128 Mainz, Germany
- Department of Physics, University of Ioannina, 45110 Ioannina, Greece
- Institute of Materials Science and Computing, University Research Center of Ioannina (URCI), 45110 Ioannina, Greece
| | - Guangzhao Zhang
- Faculty of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China
| | - Jiajia Zhou
- South China Advanced Institute for Soft Matter Science and Technology, School of Emergent Soft Matter, South China University of Technology, Guangzhou 510640, China
- Guangdong Provincial Key Laboratory of Functional and Intelligent Hybrid Materials and Devices, South China University of Technology, Guangzhou 510640, China
| |
Collapse
|
2
|
Kong W, Neuman A, Zhang AC, Lee D, Riggleman RA, Composto RJ. Capillary filling dynamics of polymer melts in a bicontinuous nanoporous scaffold. J Chem Phys 2024; 160:044904. [PMID: 38270239 DOI: 10.1063/5.0184427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 01/01/2024] [Indexed: 01/26/2024] Open
Abstract
Polymer infiltrated nanoporous gold is prepared by infiltrating polymer melts into a bicontinuous, nanoporous gold (NPG) scaffold. Polystyrene (PS) films with molecular weights (Mw) from 424 to 1133 kDa are infiltrated into a NPG scaffold (∼120 nm), with a pore radius (Rp) and pore volume fraction of 37.5 nm and 50%, respectively. The confinement ratios (Γ=RgRp) range from 0.47 to 0.77, suggesting that the polymers inside the pores are moderately confined. The time for PS to achieve 80% infiltration (τ80%) is determined using in situ spectroscopic ellipsometry at 150 °C. The kinetics of infiltration scales weaker with Mw, τ80%∝Mw1.30±0.20, than expected from bulk viscosity Mw3.4. Furthermore, the effective viscosity of the PS melt inside NPG, inferred from the Lucas-Washburn model, is reduced by more than one order of magnitude compared to the bulk. Molecular dynamics simulation results are in good agreement with experiments predicting scaling as Mw1.4. The reduced dependence of Mw and the enhanced kinetics of infiltration are attributed to a reduction in chain entanglement density during infiltration and a reduction in polymer-wall friction with increasing polymer molecular weight. Compared to the traditional approach involving adding discrete particles into the polymer matrix, these studies show that nanocomposites with higher loading can be readily prepared, and that kinetics of infiltration are faster due to polymer confinement inside pores. These films have potential as actuators when filled with stimuli-responsive polymers as well as polymer electrolyte and fuel cell membranes.
Collapse
Affiliation(s)
- Weiwei Kong
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Anastasia Neuman
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Aria C Zhang
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Daeyeon Lee
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Robert A Riggleman
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Russell J Composto
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| |
Collapse
|
3
|
Ren T, Hinton ZR, Huang R, Epps TH, Korley L, Gorte RJ, Lee D. Increase in the effective viscosity of polyethylene under extreme nanoconfinement. J Chem Phys 2024; 160:024909. [PMID: 38214386 DOI: 10.1063/5.0185144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2023] [Accepted: 12/12/2023] [Indexed: 01/13/2024] Open
Abstract
Understanding polymer transport in nanopores is crucial for optimizing heterogeneously catalyzed processes in polymer upcycling and fabricating high-performance nanocomposite films and membranes. Although confined polymer dynamics have been extensively studied, the behavior of polyethylene (PE)-the most widely used commodity polymer-in pores smaller than 20 nm remains largely unexplored. We investigate the effects of extreme nanoconfinement on PE transport using capillary rise infiltration in silica nanoparticle packings with average pore radii ranging from ∼1 to ∼9 nm. Using in situ ellipsometry and the Lucas-Washburn model, we discover a previously unknown inverse relationship between effective viscosity (ηeff) and average pore radius (Rpore). Additonally, we determine that PE transport under these extreme conditions is primarily governed by physical confinement, rather than pore surface chemistry. We refine an existing theory to provide a generalized formalism to describe the polymer transport dynamics over a wide range of pore radii (from 1 nm and larger). Our results offer valuable insights for optimizing catalyst supports in polymer upcycling and improving infiltration processes for nanocomposite fabrication.
Collapse
Affiliation(s)
- Tian Ren
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Center for Plastics Innovation, University of Delaware, Newark, Delaware 19716, USA
| | - Zachary R Hinton
- Center for Plastics Innovation, University of Delaware, Newark, Delaware 19716, USA
- Department of Materials Science and Engineering, University of Delaware, Newark, Delaware 19716, USA
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, USA
| | - Renjing Huang
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Thomas H Epps
- Center for Plastics Innovation, University of Delaware, Newark, Delaware 19716, USA
- Department of Materials Science and Engineering, University of Delaware, Newark, Delaware 19716, USA
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, USA
| | - LaShanda Korley
- Center for Plastics Innovation, University of Delaware, Newark, Delaware 19716, USA
- Department of Materials Science and Engineering, University of Delaware, Newark, Delaware 19716, USA
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, USA
| | - Raymond J Gorte
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Center for Plastics Innovation, University of Delaware, Newark, Delaware 19716, USA
| | - Daeyeon Lee
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Center for Plastics Innovation, University of Delaware, Newark, Delaware 19716, USA
| |
Collapse
|
4
|
Kawaguchi D, Sasahara K, Inutsuka M, Abe T, Yamamoto S, Tanaka K. Absolute local conformation of poly(methyl methacrylate) chains adsorbed on a quartz surface. J Chem Phys 2023; 159:244902. [PMID: 38146829 DOI: 10.1063/5.0184315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 11/30/2023] [Indexed: 12/27/2023] Open
Abstract
Polymer chains at a buried interface with an inorganic solid play a critical role in the performance of polymer nanocomposites and adhesives. Sum frequency generation (SFG) vibrational spectroscopy with a sub-nanometer depth resolution provides valuable information regarding the orientation angle of functional groups at interfaces. However, in the case of conventional SFG, since the signal intensity is proportional to the square of the second-order nonlinear optical susceptibility and thereby loses phase information, it cannot be unambiguously determined whether the functional groups face upward or downward. This problem can be solved by phase-sensitive SFG (ps-SFG). We here applied ps-SFG to poly(methyl methacrylate) (PMMA) chains in direct contact with a quartz surface, shedding light on the local conformation of chains adsorbed onto the solid surface. The measurements made it possible to determine the absolute orientation of the ester methyl groups of PMMA, which were oriented toward the quartz interface. Combining ps-SFG with all-atomistic molecular dynamics simulation, the distribution of the local conformation and the driving force are also discussed.
Collapse
Affiliation(s)
- Daisuke Kawaguchi
- Department of Applied Chemistry, Kyushu University, Fukuoka 819-0395, Japan
- Center for Polymer Interface and Molecular Adhesion Science, Kyushu University, Fukuoka 819-0395, Japan
| | - Kazuki Sasahara
- Department of Applied Chemistry, Kyushu University, Fukuoka 819-0395, Japan
| | - Manabu Inutsuka
- Department of Applied Chemistry, Kyushu University, Fukuoka 819-0395, Japan
| | - Tatsuki Abe
- Department of Applied Chemistry, Kyushu University, Fukuoka 819-0395, Japan
| | - Satoru Yamamoto
- Center for Polymer Interface and Molecular Adhesion Science, Kyushu University, Fukuoka 819-0395, Japan
| | - Keiji Tanaka
- Department of Applied Chemistry, Kyushu University, Fukuoka 819-0395, Japan
- Center for Polymer Interface and Molecular Adhesion Science, Kyushu University, Fukuoka 819-0395, Japan
| |
Collapse
|
5
|
Hwang U, Nam JD, Lee D. Dual Porosity-Enhanced Antireflection Coatings with Continuous Gradient. ACS APPLIED MATERIALS & INTERFACES 2023; 15:40913-40922. [PMID: 37585736 DOI: 10.1021/acsami.3c07254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/18/2023]
Abstract
The incorporation of porous structures into films and coatings can transform their properties for applications in optics, separation, electronics, and energy generation and storage. Packing nanoparticles (NPs) is a versatile approach for fabricating nanoporous films with a tunable structure and properties. The mechanical fragility of NP packing-based films and coatings, however, significantly impedes their widespread utilization. Although infiltrating a polymer into the interstices of these NP packings has been shown to enhance their mechanical durability, this method completely eliminates the porosity of the structures, compromising their properties and functionality. This study presents a new approach to fabricate highly loaded porous nanocomposite films with a gradient in the refractive index by infiltrating subsaturating amounts of poly(methyl methacrylate) (PMMA) into disordered packings of hollow silica NPs. We demonstrate that dual porosity is a critical feature that enhances their antireflection (AR) and mechanical properties. The hollow cores of NPs prevent a substantial increase in the refractive index of the resulting films. Moreover, the interparticle voids allow for mechanical reinforcement to occur when the NP packings are infiltrated with PMMA, making them even more suitable for AR coatings. The refractive index and gradient across the nanocomposites can be tailored by adjusting the amount of PMMA infiltrated into the NP packing, the shape of hollow NPs, and the annealing time. The nanocomposite coatings with a continuous gradient in refractive index exhibit excellent AR properties and enhanced mechanical durability. Combined with the unique structural tunability afforded by the dual porosity, this approach provides a scalable and effective way to create robust and graded nanoporous structures for various applications.
Collapse
Affiliation(s)
- Uiseok Hwang
- Department of Chemical and Biomolecular Engineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
- Department of Polymer Science and Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Jae-Do Nam
- Department of Polymer Science and Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Daeyeon Lee
- Department of Chemical and Biomolecular Engineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| |
Collapse
|
6
|
Zhang J, Lei J, Tian W, Zhang G, Floudas G, Zhou J. Capillary Filling of Polymer Chains in Nanopores. Macromolecules 2023. [DOI: 10.1021/acs.macromol.2c02157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2023]
Affiliation(s)
- Jianwei Zhang
- Faculty of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China
| | - Jinyu Lei
- Faculty of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China
| | - Wenzhang Tian
- Faculty of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China
| | - Guangzhao Zhang
- Faculty of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China
| | - George Floudas
- Max Planck Institute for Polymer Research, 55128 Mainz, Germany
- Department of Physics, University of Ioannina, 45110 Ioannina, Greece
- Institute of Materials Science and Computing, University Research Center of Ioannina (URCI), 45110 Ioannina, Greece
| | - Jiajia Zhou
- South China Advanced Institute for Soft Matter Science and Technology, School of Emergent Soft Matter, South China University of Technology, Guangzhou 510640, China
- Guangdong Provincial Key Laboratory of Functional and Intelligent Hybrid Materials and Devices, South China University of Technology, Guangzhou 510640, China
| |
Collapse
|
7
|
Qiang Y, Turner KT, Lee D. Role of Polymer–Nanoparticle Interactions on the Fracture Toughness of Polymer-Infiltrated Nanoparticle Films. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c01567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Yiwei Qiang
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Kevin T. Turner
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
- Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Daeyeon Lee
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| |
Collapse
|
8
|
Venkatesh RB, Lee D. Interfacial Friction Controls the Motion of Confined Polymers in the Pores of Nanoparticle Packings. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c01282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- R. Bharath Venkatesh
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Daeyeon Lee
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| |
Collapse
|