interpenetrating networks
Recently Published Documents


TOTAL DOCUMENTS

457
(FIVE YEARS 77)

H-INDEX

49
(FIVE YEARS 6)

2022 ◽  
Vol 9 ◽  
Author(s):  
Edigar Muchuweni ◽  
Edwin T. Mombeshora ◽  
Bice S. Martincigh ◽  
Vincent O. Nyamori

In recent years, carbon-based materials, particularly carbon nanotubes (CNTs), have gained intensive research attention in the fabrication of organic solar cells (OSCs) due to their outstanding physicochemical properties, low-cost, environmental friendliness and the natural abundance of carbon. In this regard, the low sheet resistance and high optical transmittance of CNTs enables their application as alternative anodes to the widely used indium tin oxide (ITO), which is toxic, expensive and scarce. Also, the synergy between the large specific surface area and high electrical conductivity of CNTs provides both large donor-acceptor interfaces and conductive interpenetrating networks for exciton dissociation and charge carrier transport. Furthermore, the facile tunability of the energy levels of CNTs provides proper energy level alignment between the active layer and electrodes for effective extraction and transportation of charge carriers. In addition, the hydrophobic nature and high thermal conductivity of CNTs enables them to form protective layers that improve the moisture and thermal stability of OSCs, thereby prolonging the devices’ lifetime. Recently, the introduction of CNTs into OSCs produced a substantial increase in efficiency from ∼0.68 to above 14.00%. Thus, further optimization of the optoelectronic properties of CNTs can conceivably help OSCs to compete with silicon solar cells that have been commercialized. Therefore, this study presents the recent breakthroughs in efficiency and stability of OSCs, achieved mainly over 2018–2021 by incorporating CNTs into electrodes, active layers and charge transport layers. The challenges, advantages and recommendations for the fabrication of low-cost, highly efficient and sustainable next-generation OSCs are also discussed, to open up avenues for commercialization.


2021 ◽  
pp. 52073
Author(s):  
Wenjie Sun ◽  
Jiaming Luo ◽  
Lei Zhang ◽  
Yujie Liang ◽  
Yue Chen ◽  
...  

Gels ◽  
2021 ◽  
Vol 7 (4) ◽  
pp. 277
Author(s):  
Kamol Dey ◽  
Silvia Agnelli ◽  
Elisa Borsani ◽  
Luciana Sartore

The mechanical milieu of the extracellular matrix (ECM) plays a key role in modulating the cellular responses. The native ECM exhibits viscoelasticity with stress relaxation behavior. Here, we reported the preparation of degradation-mediated stress relaxing semi-interpenetrating (semi-IPN) polymeric networks of hydroxyethyl cellulose in the crosslinked gelatin-polyethylene glycol (PEG) architecture, leveraging a newly developed synthesis protocol which successively includes one-pot gelation under physiological conditions, freeze-drying and a post-curing process. Fourier transform infrared (FTIR) confirmed the formation of the semi-IPN blend mixture. A surface morphology analysis revealed an open pore porous structure with a compact skin on the surface. The hydrogel showed a high water-absorption ability (720.00 ± 32.0%) indicating the ability of retaining a hydrophilic nature even after covalent crosslinking with functionalized PEG. Detailed mechanical properties such as tensile, compressive, cyclic compression and stress relaxation tests were conducted at different intervals over 28 days of hydrolytic degradation. Overall, the collective mechanical properties of the hydrogel resembled the mechanics of cartilage tissue. The rate of stress relaxation gradually increased with an increasing swelling ratio. Hydrolytic degradation led to a marked increase in the percentage dissipation energy and stress relaxation response, indicating the degradation-dependent viscoelasticity of the hydrogel. Strikingly, the hydrogel maintained the structural stability even after degrading two-thirds of its initial mass after a month-long hydrolytic degradation. This study demonstrates that this semi-IPN G-PEG-HEC hydrogel possesses bright prospects as a potential scaffolding material in tissue engineering.


2021 ◽  
Vol 25 ◽  
pp. 101246
Author(s):  
Lin Wang ◽  
Shanshan Wu ◽  
Xing Guo ◽  
Jing Fan ◽  
Shaobing Zhou ◽  
...  

2021 ◽  
Vol 3 ◽  
pp. 97-107
Author(s):  
N.М. Zhunusbekova ◽  
◽  
Т.К. Iskakova ◽  
N.S. Chinibayeva ◽  
G.К. Kussainova ◽  
...  

The presence of a three-dimensional hydrophilic network structure ensures the uniqueness and wide practical application of hydrogels in industry, medicine, agriculture, etc. On their basis, soft contact lenses, dressings, superabsorbents, catalysts, soil structuring agents, preventing root drying and improving plant survival, have been created. The aimof this work is to synthesize new water-swellable polymer composites by combining monomer units of various natures based on acrylic acid and agar-agar with imidazole, differing in hydrophilic-hydrophobic balance. Results and discussion: The synthesis of new double and ternary polymer composites based on acrylic acid and agar-agar with imidazole was carried out, their physicochemical and complex-forming properties with transition metal ions in an aqueous medium were investigated. Comparative analysis showed that the complexation of interpenetrating networks with FeCl3 is more pronounced than with CoCl2. This fact can be associated with the difficulty of introducing a cobalt ion into the ligand plane during the formation of a metal complex, which further affects the binding to the functional groups of the network. The specific binding of the obtained polymer composites with metal salts was shown, which is carried out through the formation of ion pairs with the participation of counterions and coordination-unsaturated metals, which make the main contribution to the formation of extracomplexes and are responsible for the coordination of oxygen-containing ligands.


Author(s):  
Damian Jędrzejowski ◽  
Marzena Pander ◽  
Wojciech Nitek ◽  
Wojciech Bury ◽  
Dariusz Matoga

Author(s):  
A. V. Shibaev ◽  
D. A. Muravlev ◽  
V. V. Skoi ◽  
A. V. Rogachev ◽  
A. I. Kuklin ◽  
...  

Micromachines ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 943
Author(s):  
Jeongah Kim ◽  
Bo-Young Kim ◽  
Seong Dae Park ◽  
Ji-Hun Seo ◽  
Chan-Jae Lee ◽  
...  

Because electronics are becoming flexible, the demand for techniques to manufacture thin flexible printed circuit boards (FPCBs) has increased. Conventional FPCBs are fabricated by attaching a coverlay film (41 μm) onto copper patterns/polyimide (PI) film to produce the structure of coverlay/Cu patterns/PI film. Given that the conventional coverlay consists of two layers of polyimide film and adhesive, its thickness must be reduced to generate thinner FPCBs. In this study, we fabricated 25-μm-thick poly(amide-imide-urethane)/epoxy interpenetrating networks (IPNs) to replace the thick conventional coverlay. Poly(amide-imide-urethane) (PAIU) was synthesized by reacting isocyanate-capped polyurethane with trimellitic anhydride and then mixed with epoxy resin to produce PAIU/epoxy IPNs after curing. Thanks to the soft segments of polyurethane, the elongation of PAIU/epoxy IPNs increased with increasing PAIU content and reached over 200%. After confirming the excellent thermal stability and chemical resistance of the PAIU/epoxy IPNs, we fabricated FPCBs by equipping them as coverlays. The mechanical durability of the FPCBs was evaluated through an MIT folding test, and the FPCB fabricated with PAIU/ep-2 was stable up to 164 folding cycles because of the balanced mechanical properties.


Sign in / Sign up

Export Citation Format

Share Document