Article
Engineering, Environmental
Eunse Chang, Jinchuan Zhao, Chongxiang Zhao, Guangming Li, Patrick C. Lee, Chul B. Park
Summary: A new toughening strategy with nano-structured rubber inclusion is proposed in this study, which effectively enhances the toughness of polypropylene. By integrating vulcanization and in situ fibrillation processes, PP nanocomposites toughened with EPDM nano-fibrils are successfully fabricated, leading to unique properties and improved fracture behavior at a lower EPDM loading. The superior toughening efficiency of the crosslinked EPDM nanofibrillar network may be explained by a collective toughening mechanism involving multiple micro-scale mechanisms.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Yongzheng Shi, Na Yang, Jin Niu, Shubin Yang, Feng Wang
Summary: A rubber-derived lithium-conducting elastomer with high resilience and improved ionic conductivity has been developed by sulfur vulcanization of nitrile butadiene rubber with a polymerizable ionic liquid. The elastic lithium-conductor exhibits high resilience, excellent cyclic durability, and high room-temperature ionic conductivity, leading to a solid-state lithium/LiFePO4 battery with high capacity and capacity retention.
Article
Chemistry, Applied
F. Cantamessa, F. Carniato, A. Fina
Summary: This paper discusses the preparation of thermoreversibly crosslinked composite rubbers that are industrially viable and environmentally sustainable. A maleimide-functionalized silica (Sil-M) is used as a reinforcement filler and crosslinking agent on furan-grafted ethylene-propylene rubber (EPRgF) via Diels-Alders reaction. The composite rubbers are prepared by reactive melt blending without using organic solvents. Mechanical properties are compared between EPRgF/Sil-M and unfunctionalized EPRgF/Sil to show the impact of DA crosslinking. The study also investigates the combination of Sil-M and bismaleimide to optimize crosslinking and material performance.
REACTIVE & FUNCTIONAL POLYMERS
(2023)
Article
Chemistry, Physical
Xiaoxiao Guo, Shujian Cheng, Ke Xu, Bo Yan, Yile Li, Weiwei Cai, Jiafa Cai, Binbin Xu, Yinghui Zhou, Yufeng Zhang, Xue-ao Zhang
Summary: In this study, graphene aerogels are transformed from thermal insulators to thermal conductors through high-temperature annealing. The annealed graphene aerogels exhibit high thermal conductivity and excellent elasticity, making them suitable for thermal management of high-power electronic devices.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2022)
Article
Materials Science, Ceramics
Sawao Honda, Shinobu Hashimoto, Benoit Nait-Ali, David S. Smith, Yusuke Daiko, Yuji Iwamoto
Summary: Highly textured porous alumina was successfully fabricated using pulse electric current sintering (PECS) method, and its properties were measured in two directions. It was found that the porosity and thermal conductivity of the porous alumina varied along different directions, and the bending strength and thermal shock strength also showed significant differences in the two directions.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2022)
Article
Polymer Science
Yulong Zhang, Wei Liu, Qiang Zhou, Yiting Meng, Ye Zhong, Jing Xu, Chuan Xiao, Guangpu Zhang, Yanan Zhang
Summary: A new hydrophobic reinforcing filler was developed by modifying the hydrophilic surface of silica particles using a vinyl silazane coupling agent. The modified particles showed reduced aggregation of hydrophobic particles. The study also investigated the effects of the vinyl-modified silica particles on the dispersibility, rheology, and thermal and mechanical properties of liquid silicone rubber composites for high-performance silicone rubber matrix. The results demonstrated that the vinyl-modified silica rubber composites had lower viscosity and higher thermal stability, conductivity, and mechanical strength compared to silica rubber composites.
Article
Chemistry, Multidisciplinary
Yuge Ouyang, Xiaofei Li, Huafeng Tian, Liuyang Bai, Fangli Yuan
Summary: This paper introduces a thermal conductive polymer composite consisting of silicone rubber and branched Al2O3, with a continuous three-dimensional network structure and high thermal conductivity. The composite meets the requirements in the field of electrical insulation, while also having high strength and improved performance parameters.
Article
Materials Science, Ceramics
Mitsuhiro Ishida, Yutaro Sashiyama, Hirofumi Akamatsu, Katsuro Hayashi, Kazuki Nakanishi, George Hasegawa
Summary: Porous polyimide (PI) monoliths were successfully synthesized from porous poly(amic acid) (PAA) xerogels by thermal imidization. The PAA xerogels exhibited low-density and good morphological stability, while the PI monoliths had higher porosity and flexibility. The porous PI thermal insulators demonstrated high temperature stability in air.
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
(2022)
Article
Nanoscience & Nanotechnology
Shizhou Jiang, Dmitry Lebedev, Loren Andrews, J. Tyler Gish, Thomas W. Song, Mark C. Hersam, Oluwaseyi Balogun
Summary: Two-dimensional (2D) semiconductors with ambient encapsulation exhibit unique physical properties desirable for various applications. However, limited studies have been conducted on the in-plane thermal conductivity measurements in encapsulated 2D semiconductors. To address this challenge, the authors integrated the FDTR and OTRS techniques in the same experimental platform.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Materials Science, Composites
Dan Yang, Qungui Wei, Liyuan Yu, Yufeng Ni, Liqun Zhang
Summary: Functionalized hexagonal boron nitride platelets modified and grafted with bis-(gamma-triethoxysilylpropyl)-tetrasulfide were used to prepare BN-PCPA-Si69/NR composites with significantly improved thermal conductivity, mechanical properties, and dielectric characteristics. The composite with 30% volume content of BN-PCPA-Si69 platelets showed a 5.4-fold increase in thermal conductivity and a maximum tensile strength of 17.0 MPa.
COMPOSITES SCIENCE AND TECHNOLOGY
(2021)
Review
Polymer Science
Zulfiqar Ali, Yuan Gao, Bo Tang, Xinfeng Wu, Ying Wang, Maohua Li, Xiao Hou, Linhong Li, Nan Jiang, Jinhong Yu
Summary: This paper discusses the research progress and application of carbon fiber composites as thermal management materials, focusing on the mechanical properties and thermal conductivity of carbon fiber, as well as its advantages in preparing thermal conduction paths.
Article
Polymer Science
Bai Han, Jinghui Dai, Wanliang Zhao, Wei Song, Zhi Sun, Xuan Wang
Summary: Nanocomposite doping and the introduction of thermal conductivity groups are effective methods to improve the dielectric properties and thermal conductivity of polyethylene. In this study, functionalized nano-zeolite was successfully prepared and doped in polyethylene to prepare nanocomposites. The porous structure of the nano-zeolite and the introduction of TAICS-ZSM-5-HBP particles greatly improved the thermal conductivity of the nanocomposites.
Article
Electrochemistry
Rafael Barbosa, Roger Goncalves, Guilherme Eduardo de Oliveira Blanco, Matheus Colovati Saccardo, Kaique Afonso Tozzi, Ariel Gustavo Zuquello, Carlos Henrique Scuracchio
Summary: This study analyzed the applicability of natural rubber nanocomposites filled with carbon black and carbon nanotubes as multisensory devices through Electrochemical Impedance Spectroscopy (EIS). The results showed that impedance magnitude can be used instead of calculated resistivity, especially in lower and medium strain ranges. In higher strains, capacitive behavior becomes predominant, and piezo-capacitance becomes the ideal parameter to be measured providing higher sensitivities.
ELECTROCHIMICA ACTA
(2022)
Article
Thermodynamics
Dongliang Ding, Qiuyu Zhang, Guangzhao Qin, Yanhui Chen
Summary: Thermal conductivity of polymer composites with oriented anisotropic fillers is accurately predicted using a super-cell model with off-set fillers based on a hexagonal prism primitive-cell. The model systematically evaluates the impact of various factors on the anisotropic thermal conductivity of polymer composites and shows excellent agreement with experimental results. This work provides a practical means to predict thermal conductivity and has guiding significance for designing thermal management materials.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Engineering, Chemical
Li Xu, Liqian Zhu, Suyun Jie, Zhiyang Bu, Bo-Geng Li
Summary: The reversibly cross-linked rubber based on reversible covalent bonds is prepared through chain extension and cross-linking reactions, and it has controllable mechanical and thermal properties, as well as recyclability and self-healing at high temperature due to the exchange reaction of imine bonds.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2022)
Article
Polymer Science
David Nieto Simavilla, Aristotelis P. Sgouros, Georgios G. Vogiatzis, Christos Tzoumanekas, Vasilis Georgilas, Wilco M. H. Verbeeten, Doros N. Theodorou
Article
Polymer Science
Cristian Rodriguez-Tinoco, David Nieto Simavilla, Rodney D. Priestley, Michael Wuebbenhorst, Simone Napolitano
Article
Chemistry, Physical
Andres Cordoba, Jay D. Schieber, Tsutomu Indei
JOURNAL OF CHEMICAL PHYSICS
(2020)
Article
Polymer Science
David Nieto Simavilla, Anabella A. Abate, Jie Liu, Yves H. Geerts, Patricia Losada-Perez, Simone Napolitano
Summary: The study found that the beta relaxation slows down upon heating in a specific temperature range, but this phenomenon gradually disappears under confinement at the nanoscale level. Regardless of sample size, the relaxation dynamics could be described using an asymmetric double well potential.
Article
Biochemistry & Molecular Biology
Sameer Varma, Joseph P. R. O. Orgel, Jay D. Schieber
Summary: The study found that removal of hydroxylation has minimal effect on the macroscopic structure of collagen, but does have some impact on local structure, hydrogen bonding capacity, and electrostatic attraction. Experimental observations show that hydroxylation removal has minimal effect on collagen's D-band length, gap-overlap ratio, monomer width, and monomer length. Interestingly, de-hydroxylation also has a minor effect on the fibril's Young's modulus, with accompanying changes in triple-helix windings.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2021)
Article
Polymer Science
Diego Becerra, Andres Cordoba, Jay D. Schieber
Summary: The study using the discrete slip-link model (DSM) reveals nonuniversality in the nonlinear rheology of polymer melts at large strain rates during the inception of shear flow, despite the theory predicting universal behavior for maximum shear stress and strain at maximum stress based on entanglement activity and Kuhn steps. Primitive path stretching is shown to correspond to the transition of strain-rate-free values to values that scale with dimensionless strain rate. Additionally, differences in scaling exponents for melt and solution data suggest variations in steady-state shear stress, with DSM showing agreement with melt data.
Article
Mechanics
Jay D. Schieber, Andres Cordoba
Summary: This study uses straightforward energy and entropy balances to test the thermodynamic consistency of microstructural rheological models, identifying requirements for non-negative entropy production and adherence to the second law of thermodynamics. Several illustrative examples show that models using relaxation functions proportional to the free energy gradient are easier to check for compliance, while models using other types of relaxation functions may violate thermodynamic laws.
Article
Polymer Science
Andy Kiessling, David Nieto Simavilla, Georgios G. Vogiatzis, David C. Venerus
Summary: Thermal conductivity is an important property in determining the performance of polymers, but its dependence on molecular weight is found to be minimal and not proportional to the square root of the molecular weight as previously accepted.
Article
Mechanics
Jeffrey G. Ethier, Pouria Nourian, Rafikul Islam, Rajesh Khare, Jay D. Schieber
Summary: The text discusses extracting viscoelastic properties of a complex fluid using single-particle microrheology by embedding a micrometer-sized particle and tracking its motion through the fluid. It introduces a simple correction to the GSE equation to improve accuracy in molecular dynamics simulations. The corrected HSE equation allows for smaller box sizes, significantly reducing computational costs.
JOURNAL OF RHEOLOGY
(2021)
Article
Mechanics
Andres Cordoba, Jay D. Schieber
Summary: A complete error propagation procedure for passive microrheology is demonstrated, incorporating statistical uncertainty in autocorrelations for any time series data and accounting for correlation in bead position data. Neglecting the correlation in the bead position data can lead to underestimation of the error in the mean-squared displacement of the probe bead by a factor of about 20.
Article
Mechanics
David Nieto Simavilla, Marco Ellero
Summary: In this study, a mesoscopic viscoelastic fluid that mimics polymeric solutions was used to investigate the flow around a periodic array of cylinders. The balance between inertia and elasticity in the flow was studied, and it was found that increasing the flow rate initially reduces the drag coefficient on the cylinder, but beyond a critical point, inertia becomes dominant and causes drag enhancement. The study also observed the migration of polymer chains away from the channel walls and in the wake of the cylinder, which was attributed to stress gradients induced by the curvature of streamlines and convection of the depleted layers at the walls.
JOURNAL OF NON-NEWTONIAN FLUID MECHANICS
(2022)
Article
Oncology
Marcela Mercado-Montoya, Tatiana Gomez-Bustamante, Enrique Berjano, Steven Mickelsen, James Daniels, Pablo Hernandez-Arango, Jay Schieber, Erik Kulstad
Summary: Proactive esophageal cooling significantly reduces temperatures and damage in the esophagus during high-power short-duration ablation. These findings provide a mechanistic rationale for the high level of safety achieved so far using proactive esophageal cooling and highlight the inadequacy of temperature monitoring alone in avoiding thermal damage to the esophagus.
INTERNATIONAL JOURNAL OF HYPERTHERMIA
(2022)
Article
Mechanics
D. Nieto Simavilla, P. Espano, M. Ellero
Summary: This work investigates the eigendynamics of the conformation tensor in polymer solutions and separates the effects of nonaffine motion from other sources of non-Newtonian behavior. The study proposes a micro-macromapping approach to improve polymer constitutive modeling in multiscale simulations.
JOURNAL OF RHEOLOGY
(2023)
Article
Chemistry, Physical
D. Nieto Simavilla, V Ramakrishnan, S. K. Smoukov, D. C. Venerus
Summary: Investigations on the diffusion of small molecules or particles in polymeric materials are important for various technologies and understanding polymer chain dynamics. This study focuses on systems where the probe size is comparable to or smaller than a characteristic length of the polymer chain. The research uses forced Rayleigh scattering to study the diffusion of a molecular probe in entangled polymer melts and finds that the diffusion coefficient is significantly larger than predicted by the Stokes-Einstein relation. Anomalous, non-Fickian diffusion is observed, where the measured diffusion coefficient can abruptly change.
Article
Physics, Fluids & Plasmas
Rudi J. A. Steenbakkers, Marat Andreev, Jay D. Schieber
Summary: This study evaluates the thermodynamic consistency of an anisotropic mobile slip-link model for entangled flexible polymers, focusing on the dynamics of entanglements and chain motion, as well as the contribution of confinement potentials to the stress tensor. The model is formulated in the framework of nonequilibrium thermodynamics, demonstrating the cancellation mechanism of stress contributions due to anisotropic confinement potentials in flow, as necessary for model validity and agreement with previous predictions.