scholarly journals Chemically Fueled Self-sorted Hydrogels

2021 ◽  
Author(s):  
Nishant Singh ◽  
Álvaro Lopéz-Acosta ◽  
Georges Formon ◽  
Thomas Hermans
Keyword(s):  
Mechanical Properties ◽  
High Precision ◽  
Supramolecular Assemblies ◽  
Gelation Kinetics ◽  
Two Component

Narcissistic self-sorting in supramolecular assemblies can help to construct materials with more complex hierarchies. Whereas controlled changes in pH or temperature have been used to this extent for two-component self-sorted gels, here we show that a chemically fueled approach can provide three-component materials with high precision. The latter materials have interesting mechanical properties, such as enhanced or suppressed stiffness, and intricate multi-step gelation kinetics. In addition, we show that we can achieve supramolecular templating, where pre-existing supramolecular fibers first act as a templates for growth of a second gelator, after which they can selectively be removed.

scholarly journals Chemically Fueled Self-sorted Hydrogels

2021 ◽  
Author(s):  
Nishant Singh ◽  
Álvaro Lopéz-Acosta ◽  
Georges Formon ◽  
Thomas Hermans
Keyword(s):  
Mechanical Properties ◽  
High Precision ◽  
Supramolecular Assemblies ◽  
Gelation Kinetics ◽  
Two Component

Narcissistic self-sorting in supramolecular assemblies can help to construct materials with more complex hierarchies. Whereas controlled changes in pH or temperature have been used to this extent for two-component self-sorted gels, here we show that a chemically fueled approach can provide three-component materials with high precision. The latter materials have interesting mechanical properties, such as enhanced or suppressed stiffness, and intricate multi-step gelation kinetics. In addition, we show that we can achieve supramolecular templating, where pre-existing supramolecular fibers first act as a templates for growth of a second gelator, after which they can selectively be removed.

scholarly journals Effect of Photoinitiator on Precursory Stability and Curing Depth of Thiol-Ene Clickable Gelatin

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1877
Author(s):  
Kai-Hung Yang ◽  
Gabriella Lindberg ◽  
Bram Soliman ◽  
Khoon Lim ◽  
Tim Woodfield ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Visible Light ◽  
Rheological Properties ◽  
Swelling Ratio ◽  
Sodium Persulfate ◽  
Photo Polymerization ◽  
Gelation Kinetics ◽  
The Stability ◽  
Over Time

Recent advances highlight the potential of photopolymerizable allylated gelatin (GelAGE) as a versatile hydrogel with highly tailorable properties. It is, however, unknown how different photoinitiating system affects the stability, gelation kinetics and curing depth of GelAGE. In this study, sol fraction, mass swelling ratio, mechanical properties, rheological properties, and curing depth were evaluated as a function of time with three photo-initiating systems: Irgacure 2959 (Ig2959; 320–500 nm), lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LAP; 320–500 nm), and ruthenium/sodium persulfate (Ru/SPS; 400–500 nm). Results demonstrated that GelAGE precursory solutions mixed with either Ig2959 or LAP remained stable over time while the Ru/SPS system enabled the onset of controllable redox polymerization without irradiation during pre-incubation. Photo-polymerization using the Ru/SPS system was significantly faster (<5 s) compared to both Ig2959 (70 s) and LAP (50 s). Plus, The Ru/SPS system was capable of polymerizing a thick construct (8.88 ± 0.94 mm), while Ig2959 (1.62 ± 0.49 mm) initiated hydrogels displayed poor penetration depth with LAP (7.38 ± 2.13 mm) in between. These results thus support the use of the visible light based Ru/SPS photo-initiator for constructs requiring rapid gelation and a good curing depth while Ig2959 or LAP can be applied for photo-polymerization of GelAGE materials requiring long-term incubation prior to application if UV is not a concern.

scholarly journals Adhesive Bonding of Aluminium Alloy A5754 by Epoxy Resins

10.14311/1835 ◽  
2013 ◽  
Vol 53 (4) ◽  
Author(s):  
Ivan Michalec ◽  
Milan Marônek
Keyword(s):  
Mechanical Properties ◽  
Thermal Stability ◽  
Aluminium Alloy ◽  
Epoxy Resins ◽  
Adhesive Bonding ◽  
Thin Sheets ◽  
Two Component ◽  
Promising Area

Joining thin sheets of aluminium and its alloys is a promising area in the field of joining materials. Nowadays, joining methods that do not melt the material itself are increasingly being utilised. This paper deals with adhesive bonding of aluminium alloy A5754 by two-component epoxy resins. Theresults show that joints bonded by Hysol 9466 have appropriate mechanical properties, but that joints bonded by Hysol 9492 have better thermal stability.

Spinning Process and Mechanical Properties Analysis of PTT Filament Core Spun Yarn

2011 ◽  
Vol 239-242 ◽  
pp. 1207-1210
Author(s):  
Yuan Xue ◽  
En Long Yang
Keyword(s):  
Mechanical Properties ◽  
Mechanical Property ◽  
Elastic Recovery ◽  
Staple Fiber ◽  
Ring Spinning ◽  
The Core ◽  
Outer Sheath ◽  
Spun Yarn ◽  
Two Component ◽  
Spinning Process

The two component filament/staple fiber core-spun yarn is spun on FA506 ring spinning frame with PTT filament as interlaced yarn and Tencel staple fiber as outer sheath. The spinning process and process parameters were analyzed. The morphology, mechanical property and wear-resisting property of two component core-spun yarn were tested. Results indicate that elastic recovery rate of core-spun is up to 90.6%; broken strength is up to 20 cN/tex after boiling water treatment. The core-spun yarn can be used as a new kind of knitting yarn for sweater.

scholarly journals Annealing multicomponent supramolecular gels

Nanoscale ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 3275-3280 ◽  
Author(s):  
Ana M. Fuentes-Caparrós ◽  
Francisco de Paula Gómez-Franco ◽  
Bart Dietrich ◽  
Claire Wilson ◽  
Christopher Brasnett ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Supramolecular Gel ◽  
Two Component ◽  
Supramolecular Gels

Annealing in a two-component supramolecular gel leads to a self-sorted network, which has significantly different mechanical properties to the as-prepared gels.

Mechanical Properties of AlSi9Mg Alloy with a Sodium Modifier

2014 ◽  
Vol 223 ◽  
pp. 78-86
Author(s):  
Tomasz Lipiński ◽  
Paweł Szabracki
Keyword(s):  
Mechanical Properties ◽  
Aluminium Alloys ◽  
Silicon Content ◽  
Eutectic Phase ◽  
Coarse Grained ◽  
Hypoeutectic Alloy ◽  
Β Phase ◽  
Two Component ◽  
Si Content ◽  
Direct Use

Al–Si alloys are among the most popular casting metals. Two-component aluminium alloys with silicon are not suitable for direct use after melting. Subject to their silicon content, Al Si alloys have a coarse-grained eutectic phase, and alloys with more than 13% Si content also feature large crystallites or β-phase needles. The β-phase is hard, but also fragile. Large crystallites are good planes of division, and they reduce the mechanical properties of alloys.In this study, the Al-9% Si alloy was refined with a sodium modifier. The modifier was added to the mould by the in-mould method. The modifier's influence on the microstructure and mechanical properties of the alloy was presented graphically. The results of the analysis indicate that the compound modifier influenced the evaluated properties of the Al-9%Si hypoeutectic alloy.

Interfacial Structure and Lattice Mismatch in Lamellar TiAl Alloys

1994 ◽  
Vol 364 ◽  
Author(s):  
Dennis M. Dimiduk ◽  
Yongqian Sun ◽  
Peter M. Hazzledine
Keyword(s):  
Mechanical Properties ◽  
High Precision ◽  
Lattice Mismatch ◽  
Interfacial Structure ◽  
Internal Stresses ◽  
Tial Alloys ◽  
Weak Beam ◽  
Convergent Beam ◽  
Beam Diffraction ◽  
Twist Boundaries

AbstractThe gamma lamellae in TiAI alloys are rotated relative to each other approximately by multiples of 60˚ so that close packed planes and directions nearly align. However, the deviations caused by the tetragonality of the lattice are important in determining the structure of the interfaces and the internal stresses in the lamellae. These, in turn, strongly affect the mechanical properties of the alloys. In this paper two new electron optical techniques are used to quantify the deviations from pure twist boundaries (1) selected area diffraction from two adjacent twin-related lamellae permits c/a to be measured with high precision, (2) convergent beam diffraction is used to measure tilt components of lamellar boundaries and also rotations of vectors within the lamellar boundaries. The results are discussed in connection with the weak beam observations of interface dislocation structures.

Design of the Novel Calibration Platform for Piezoelectric Dynamometers

2012 ◽  
Vol 580 ◽  
pp. 3-6
Author(s):  
Chang Yin Gao ◽  
Wan Quan Li
Keyword(s):  
High Precision ◽  
Force Sensor ◽  
Vertical Force ◽  
The Novel ◽  
Calibration Standard ◽  
Static Calibration ◽  
High Rigidity ◽  
Two Component ◽  
Torque Load ◽  
Component Force

In order to accomplish the static calibration of piezoelectric dynamometer, the principle and structure of a multifunctional high-precision, high rigidity static calibration platform is manufactured in this paper. The screw loading mechanisms are used to achieve vertical force and horizontal forces, and its value can directly obtained by the standard measuring ring. The torque load adopts “force × lever arm" law, that is, the two horizontal loading mechanisms are relatively shifted to form force arm, and at the same time two parallel forces that have the same magnitude and opposite directions are generated. After accuracy and rigidity experiments, the static calibration platform has reached the calibration standard stipulated by CIRP-STCC. Undoubtedly, the calibration platform can use to calibrate unidirectional force, two component force sensor, three-component piezoelectric dynamometer and the drilling dynamometer, such as sensitivity, linearity, repeatability, hysteresis and crosstalk.

Mechanically Modulated, Ultra-high Precision Logic Delivery of Molecules by Bio-inspired Macroporous Ceramic Sponge

MRS Advances ◽  
2017 ◽  
Vol 2 (19-20) ◽  
pp. 1125-1130 ◽  
Author(s):  
Changlu Xu ◽  
Yanjie Bai ◽  
Huilin Yang ◽  
Lei Yang
Keyword(s):  
Mechanical Properties ◽  
Controlled Release ◽  
Pore Structure ◽  
High Precision ◽  
Cyclic Deformation ◽  
Material Characterization ◽  
Drug Loading ◽  
Compressive Strain ◽  
Moisture Contents ◽  
Controlled Release System

ABSTRACTInspired by sea sponges, porous Al2O3/starch composite sponges were designed and fabricated as a new controlled release system enabling mechano-triggered logic delivery of molecules. Results of material characterization indicate that the all the composite sponges had a high macro-porosity of >80%, and dehydrated sponges revealed favorable pore structure for drug loading and retaining. The composite sponges have moisture-dependent mechanical properties and samples with appropriate moisture contents revealed high resilience and mechanical robustness under cyclic deformation. Based on the unique mechanical properties of the composite sponge, mechanically modulated, nano-gram precision delivery of model molecules was achieved in an AND logic manner gated by both moisture and compressive strain.

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