Article
Polymer Science
Dashan Mi, Zhongguo Zhao, Haiqing Bai
Summary: The orientation and dispersion of nanoparticles greatly affect the conductivity and mechanical properties of nanocomposites. This study investigates the influence of different molding methods and shear conditions on the dispersion and orientation of carbon nanotubes (CNTs) in polypropylene/CNTs nanocomposites. It is found that high dispersion of CNT agglomerates hinders the formation of a conductive network, while increased orientation of CNTs results in current only flowing in the orientation direction.
Article
Materials Science, Composites
Ashish Kaushal, Vishal Singh
Summary: In this study, the mechanical, DC conductivity, and electromagnetic interference (EMI) shielding properties of multiwalled carbon nanotubes (MWCNTs) and carbon fiber reinforced polypropylene (CNC) nanocomposites were investigated. The results showed that the combination of CF and MWCNT improved the tensile strength and modulus of the nanocomposites, and the percolation behavior improved the DC electrical conductivity. The CNC nanocomposites exhibited high EMI shielding effectiveness in the X-band for a 2 mm thick sample, and efforts have been made to develop a compatible EMI shielding material using multiple fillers.
POLYMER COMPOSITES
(2022)
Review
Materials Science, Composites
Uwa O. Uyor, Patricia A. Popoola, Olawale M. Popoola, Victor S. Aigbodion
Summary: Polypropylene (PP) is widely used in engineering applications, but lacks desired thermal properties and mechanical strength. The incorporation of carbon nanotubes (CNTs) in the PP matrix has improved its engineering properties while retaining its lightweight and flexibility. Despite challenges, the development of PP-CNTs composites shows promising advancements and has important industrial applications.
JOURNAL OF THERMOPLASTIC COMPOSITE MATERIALS
(2023)
Article
Polymer Science
Nicoleta-Violeta Stanciu, Felicia Stan, Ionut-Laurentiu Sandu, Catalin Fetecau, Adriana-Madalina Turcanu
Summary: This paper investigated the material properties of polypropylene (PP) nanocomposites filled with multi-walled carbon nanotubes (MWCNTs) and found that the addition of MWCNTs affects the melt shear viscosity, specific volume, thermal conductivity, mechanical properties, and electrical properties of the materials. The study revealed that increasing MWCNT loading results in higher melt shear viscosity, lower specific volume, thermal conductivity below 0.35 W/m·K, and the nanocomposite becomes electrically conductive at 3 wt.% loading.
Article
Materials Science, Composites
U. O. Uyor, A. P. Popoola, O. M. Popoola, V. S. Aigbodion
Summary: The study showed that significant improvements in the electrical conductivity and relative dielectric permittivity of PP-CNTs/GNs nanocomposites can be achieved by optimizing melt processing parameters.
JOURNAL OF COMPOSITE MATERIALS
(2021)
Article
Materials Science, Composites
Vivek Khare, Sudhir Kamle
Summary: The dispersion of functionalized carbon nanotubes in polypropylene was optimized and investigated using thresholding based image segmentation, with MWCNT concentration optimized up to 1%. The proposed clustering algorithm successfully detected MWCNT concentration significantly up to 1% based on SEM images. The developed nanocomposite films were then used to fabricate artificial flapping wings inspired by dragonflies, with the natural frequency found to be maximum for the 1% MWCNT-COOH-PP wing.
JOURNAL OF THERMOPLASTIC COMPOSITE MATERIALS
(2021)
Review
Chemistry, Multidisciplinary
L. Lavagna, R. Nistico, S. Musso, M. Pavese
Summary: Three decades of scientific scrutiny on carbon nanotubes (CNTs) have shown that challenges in handling and dispersing CNTs, as well as their limited interaction with other materials due to their structure, can impact technological applications. A thorough understanding of CNT properties and selecting appropriate dispersion procedures are essential for achieving desired nanocomposite properties. Advanced knowledge on CNT synthesis, functionalization methods, and dispersion techniques is crucial for addressing these challenges.
MATERIALS TODAY CHEMISTRY
(2021)
Article
Polymer Science
Mohammed H. Al-Saleh, Mohammed S. Valliyengal, Noran Mousa, Maria Ruksar
Summary: The study found that MWCNT dispersed better in HDPE, with a marginal increase in crystallinity when MWCNT was added, while the impact on LDPE crystallinity was minimal. However, the AC electrical conductivity of HDPE and LDPE nanocomposites were almost the same.
JOURNAL OF MACROMOLECULAR SCIENCE PART B-PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Moran Ben Basat, Noa Lachman
Summary: This study presents a quality control approach for water-based SWCNT dispersions using a unique combination of physical and chemical methods, with UV-Vis spectroscopy, rheological measurements, and precipitant sheet resistance as key characterization methods. The fast and easy measurement of these methods provides a quick indication of dispersion quality and stability, which can be correlated with microscopy and Raman spectroscopy for validation.
Article
Materials Science, Multidisciplinary
Taiyo Shimizu, Hideaki Nakajima, Kazufumi Kobashi, Takeo Yamada, Kenji Hata
Summary: The study focuses on controlling the electrical conductivities of CNT buckypapers by utilizing mixed dispersions of different types of CNTs, achieving seamless transitions between two sole counterparts. Additionally, an intriguing correlation between electrical conductivities and thermal diffusivities of the obtained buckypapers was discovered. This finding could provide valuable insights for applications involving both electrical and thermal conduction by CNTs.
Article
Chemistry, Multidisciplinary
Tyler Albright, Jared Hobeck
Summary: This research explores a high-fidelity stochastic modeling framework to predict the electromechanical properties of conductive polymer composites (CPCs) at bulk scales. CPC dogbone specimens are manufactured and their properties are characterized through testing. The modeled predictions agree with experimental results and are compared to predictions from an analytical model.
Article
Polymer Science
Kwan-Woo Kim, Woong Han, Byung-Joo Kim
Summary: This study investigated the effects of carbon fibers and graphite flakes on the heat dissipation properties and mechanical strength of composite materials. It was found that fillers with high thermal conductivity, such as carbon fibers and graphite flakes, improved heat dissipation performance, while carbon fibers enhanced mechanical strength. However, the performance of the composite materials varied significantly depending on the ratio of fillers. The optimal mixing ratio of fillers with different shapes was determined to achieve enhanced physical properties.
Article
Chemistry, Multidisciplinary
Ezgi Ucar, Mustafa Dogu, Elcin Demirhan, Beate Krause
Summary: This study investigates the preparation of Poly(methyl methacrylate) (PMMA)/single-walled carbon nanotubes (SWCNT) composites by melt mixing. The results show that a low electrical resistivity and suitable SWCNT dispersion and distribution can be achieved by direct incorporation method with high rotation speed. The composites exhibit a low percolation threshold of 0.05-0.075 wt%, the lowest reported for melt-mixed PMMA/SWCNT composites. The thermal behavior and thermoelectric properties of the composites were also studied.
Article
Polymer Science
Astrid Diekmann, Marvin C. V. Omelan, Ulrich Giese
Summary: Incorporating nanofillers into elastomers leads to composites with great potential, but concerns arise due to agglomeration of fillers. Different carbon nanotube pretreatment methods were analyzed to improve filler dispersion in polydimethylsiloxane (PDMS)/CNT composites. While solvent dispersion led to increased electrical conductivity, it also caused a softening effect due to solvent residues. Chemical functionalization improved compatibility but damaged CNTs, overshadowing the conductivity and reinforcement enhancement effects.
Article
Chemistry, Analytical
Abraham Balam, Raul Pech-Piste, Zarel Valdez-Nava, Fidel Gamboa, Alejandro Castillo-Atoche, Francis Aviles
Summary: The electrical and electromechanical responses of nanocomposite films consisting of carbon nanotubes and polypropylene were studied. The effects of alternating current and direct current on the electrical response were investigated. The results showed that the contribution of capacitance to the electrical response was significant at certain frequencies. The sensitivity of the piezoresistive response was higher for alternating current compared to direct current, and the sensitivity to strain was lower in the dielectric configuration.
Article
Materials Science, Composites
Oliver Voigt, Beate Krause, Petra Poetschke, Michael T. Mueller, Sven Wiessner
Summary: The thermoelectric behavior of polypropylene (PP) based nanocomposites containing single walled carbon nanotubes (SWCNTs) and five kinds of ionic liquids (Ils) dependent on composite composition and electron beam irradiation (EB) was studied. It was found that it is possible to prepare n-type melt-mixed polymer composites from p-type commercial SWCNTs with relatively high Seebeck coefficients when adding four of the selected Ils. The highest Seebeck coefficients achieved in this study were +49.3 mu V/K (PP/2 wt.% SWCNT) for p-type composites and -27.6 mu V/K (PP/2 wt.% SWCNT/4 wt.% IL type AMIM Cl) for n-type composites.
JOURNAL OF COMPOSITES SCIENCE
(2022)
Article
Biochemistry & Molecular Biology
Raghvendra Singh Anju, Raghvendra Singh Yadav, Petra Potschke, Juergen Pionteck, Beate Krause, Ivo Kuritka, Jarmila Vilcakova, David Skoda, Pavel Urbanek, Michal Machovsky, Milan Masar, Michal Urbanek
Summary: Nanocomposites consisting of CuxCo1-xFe2O4-rGO-TPU exhibit highly efficient electromagnetic interference shielding, with maximum shielding effectiveness values of 42.9 dB, 46.2 dB, and 58.8 dB. This performance is attributed to good impedance matching, conductivity, dielectric properties, and magnetic loss. These materials are promising candidates for lightweight, flexible, and highly efficient EMI shielding.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Polymer Science
Tzu-Han Kao, Zhi Qiao, Po Yuen Ho, Oliver Ditzer, Ningwei Sun, Brigitte Voit, Franziska Lissel
Summary: Polytriarylamines (PTAAs) are amorphous polymers that can be reversibly oxidized to generate stable radical cations, widely used in perovskite solar cells due to their stability. Linear unsubstituted PTAA can be synthesized for a better match with perovskite systems, providing a favorable HOMO energy level of -5.47 eV.
JOURNAL OF POLYMER SCIENCE
(2022)
Article
Engineering, Multidisciplinary
Jianwei Zhang, Gengyuan Liang, Ying Xiao, Wenshu Zhao, Jun Tang, Su Ju, Shuxin Bai, Petra Potschke, Jurgen Pionteck
Summary: In this study, a dense layered film with excellent mechanical and electrical properties was achieved by introducing CNT/PU mixture as the mortar to bind graphene layers. The film showed good compatibility with ionic liquid and exhibited potential applications in various fields, such as flexible infrared camouflage devices.
COMPOSITES PART B-ENGINEERING
(2022)
Article
Polymer Science
Carolin Bunk, Lucas Loser, Nora Fribiczer, Hartmut Komber, Lothar Jakisch, Reinhard Scholz, Brigitte Voit, Sebastian Seiffert, Kay Saalwachter, Michael Lang, Frank Bohme
Summary: A new method for synthesizing model amphiphilic polymer co-networks using heterocomplementary coupling reactions was investigated, showing nearly model-like gel structure with only a small amount of pending arms as the most significant network defects.
Article
Chemistry, Physical
Dan Xiao, Meng-Ting Zheng, Uwe Gohs, Udo Wagenknecht, Brigitte Voit, Xue-Qing Xiao, De-Yi Wang
Summary: A sustainable green electron reactive processing method was designed and developed in this study to enhance the fire safety of PP nanocomposites. The experimental results showed that electron reactive processing could reduce the smoke production and heat release rate of the PP nanocomposites without compromising their tensile properties.
RADIATION PHYSICS AND CHEMISTRY
(2022)
Article
Chemistry, Physical
Ioannis Konidakis, Beate Krause, Gyu-Hyeon Park, Nithin Pulumati, Heiko Reith, Petra Potschke, Emmanuel Stratakis
Summary: The incorporation of carbon nanotubes (CNTs) within polymer hosts offers a great platform for the development of advanced thermoelectric composite materials. Different formulations of CNT/polymer composites have been investigated to optimize their thermoelectric performance. The dynamics of charged excitons within CNTs and their derived structures have also been studied to understand the recombination processes of free charge carriers. This study focuses on the combination of thermoelectric parameters and charge carrier dynamics in CNT-containing polymer composites, and the results show the correlation between the Seebeck coefficient and exciton lifetimes, as well as the independent relationship between volume conductivity and exciton lifetimes.
ACS APPLIED ENERGY MATERIALS
(2022)
Article
Polymer Science
Xinlei Tang, Juergen Pionteck, Petra Poetschke
Summary: In this study, the piezoresistive behavior of carbon black and partially crystalline poly(vinylidene fluoride) (PVDF) composites was improved through the addition of either amorphous poly (methyl methacrylate) (PMMA) or partially crystalline poly(butylene succinate) (PBS). The addition of 30 wt% PBS significantly reduced the electrical percolation threshold, enabling the use of low concentration carbon black for piezoresistive testing. The resulting composite exhibited nearly linear piezoresistive behavior with a significantly enhanced relative electrical resistance change delta R/R-0 of 71.8 +/- 7.1% at 5% strain.
Article
Polymer Science
Antonio Jose Paleo, Beate Krause, Delfim Soares, Manuel Melle-Franco, Enrique Munoz, Petra Potschke, Ana Maria Rocha
Summary: The thermoelectric properties of melt-processed poly(ether ether ketone) (PEEK) composites with 10 wt.% of carbon nanofibers (CNFs) were investigated at temperatures ranging from 30 degrees C to 100 degrees C. The composites exhibited a negative temperature effect in their electrical conductivity and a lower Seebeck coefficient compared to the as-received CNFs. The negative Seebeck coefficient was attributed to impurities in the CNFs, while the lower Seebeck coefficient was caused by a slight electron withdrawing effect from the PEEK matrix.
Article
Chemistry, Analytical
Beate Krause, Sarah Imhoff, Brigitte Voit, Petra Poetschke
Summary: The combination of single-walled carbon nanotubes (SWCNTs) with polyvinylpyrrolidone (PVP) in melt-mixed composites was investigated for the first time. It was found that the addition of 5 wt% PVP could switch the Seebeck coefficient from positive to negative in polycarbonate (PC) composites. In poly(butylene terephthalate) (PBT) composites, the Seebeck coefficient decreased with the addition of 8 wt% PVP. However, in poly(ether ether ketone) (PEEK) composites, the effect of PVP on the Seebeck coefficient was minimal.
Article
Thermodynamics
Qusay Doraghi, Alina Zabnienska-Gora, Les Norman, Beate Krause, Petra Poetschke, Hussam Jouhara
Summary: Researchers are exploring new lead-free thermoelectric materials that can convert wasted heat into electric energy. The use of polymers with lower efficiency but higher electrical conductivity and Seebeck coefficients is increasingly discussed in the literature. This article presents two thermoelectric generator models based on polypropylene melt-mixed with single-walled carbon nanotubes, which show promising results for future TEG modules.
THERMAL SCIENCE AND ENGINEERING PROGRESS
(2023)
Article
Materials Science, Multidisciplinary
Jose Roberto Bautista-Quijano, Harald Bruenig, Petra Poetschke
Summary: The selection of suitable polymers using Hansen Solubility Parameters (HSPs) and Relative Energy Differences (REDs) for electrically conductive nanocomposites in sensor applications is discussed. Polycarbonate (PC) was found to be a highly liquid-sensitive polymer, and it can be easily spun into sensing fibers. By melt-mixing PC with carbon nanoparticles such as Multi-walled Carbon Nanotubes (MW) and Carbon Black (CB), electrically conductive materials were obtained which showed improved spinnability and sensing abilities.
MATERIALS RESEARCH EXPRESS
(2023)
Article
Polymer Science
Enrique Caldera-Cruz, Takuya Tsuda, Nataliya Kiriy, Heidi Thomas, Paulius Imbrasas, Roman Tkachov, Tim Achenbach, Sebastian Reineke, Anton Kiriy, Brigitte Voit
Summary: This study presents three novel host materials for OLEDs, which enable the fabrication of low-cost electronic devices using low-temperature solution-processing methods. These materials possess important properties and play a crucial role in OLEDs.
Article
Nanoscience & Nanotechnology
Antonio J. Paleo, Yadienka Martinez-Rubi, Beate Krause, Petra Potschke, Michael B. Jakubinek, Behnam Ashrafi, Christopher Kingston
Summary: The integration of SWCNTs in fabric-like sheets simplifies handling and allows for composites with higher nanotube contents. In this study, p-type SWCNT-TPU fabric materials with a wide range of SWCNT contents were developed using a one-step filtration method. The mechanical and thermoelectric properties of these nanocomposites were tailored by varying the SWCNT/TPU wt % ratio, resulting in improved strength and stretchability compared to pristine SWCNT buckypaper. These findings represent a significant step towards the development of easy-to-process self-supporting and stretchable materials for flexible thermoelectric devices.
ACS APPLIED NANO MATERIALS
(2023)
Article
Nanoscience & Nanotechnology
Beate Krause, Ioannis Konidakis, Emmanuel Stratakis, Petra Poetschke
Summary: Polymer composites based on polycarbonate (PC) and polyetheretherketone (PEEK) filled with single-walled carbon nanotubes (SWCNTs, 0.5-2.0 wt %) were evaluated for thermoelectric applications. Both composites showed positive Seebeck coefficients, indicating p-type thermoelectric behavior. The addition of phosphonium-based ionic liquid THTDPCl was able to change the conductivity type from p-type to n-type in both composite types. The ratio of SWCNT to IL was also found to influence the thermoelectric properties.
ACS APPLIED NANO MATERIALS
(2023)
