Impact of Network Architecture and Lipid Physical State on the Mechanical Properties and Scaling Behavior of Emulsion-filled Gelatin Gels

Fibrin gels, prepared from fibrinogen and thrombin, the key proteins involved in blood clotting, were among the first biomaterials used to prevent bleeding and promote wound healing. The unique polymerization mechanism of fibrin, which allows control of gelation times and network architecture by variation in reaction conditions, allows formation of a wide array of soft substrates under physiological conditions. Fibrin gels have been extensively studied rheologically in part because their nonlinear elasticity, characterized by soft compliance at small strains and impressive stiffening to resist larger deformations, appears essential for their function as haemostatic plugs and as matrices for cell migration and wound healing. The filaments forming a fibrin network are among the softest in nature, allowing them to deform to large extents and stiffen but not break. The biochemical and mechanical properties of fibrin have recently been exploited in numerous studies that suggest its potential for applications in medicine and bioengineering.

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Metalation/De-metalation as a Post-Gelation Strategy to Tune the Mechanical Properties of Catenane-Crosslinked Gels

10.33774/chemrxiv-2021-7hj2k ◽

2021 ◽

Author(s):

Mark A. Nosiglia ◽

Nathan D. Colley ◽

Mark S. Palmquist ◽

Abigail O. Delawder ◽

Sheila L. Tran ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Free Radical ◽

Network Architecture ◽

Tensile Testing ◽

Degrees Of Freedom ◽

Interlocked Molecules ◽

Shear Moduli ◽

Mechanical Bonding ◽

General Method

Mechanically interlocked molecules (MIMs) possess unique architectures and non-traditional degrees of freedom that arise from well-defined topologies that are achieved through precise mechanical bonding. Incorporation of MIMs into materials can thus provide an avenue to discover new and emergent macroscale properties. Here, the synthesis of a phenanthroline-based [2]catenane crosslinker and its incorporation into polyacrylate organogels is described. Specifically, Cu(I) metalation and de-metalation was used as a post-gelation strategy to tune the mechanical properties of a gel by controlling the conformational motions of integrated MIMs. The organogels were prepared via thermally initiated free radical polymerization, and Cu(I) metal was added in MeOH to pre-treated, swollen gels. De-metalation of the gels was achieved by adding cyanide salts and washing the gels. Changes in Young’s and shear moduli, as well as tensile strength, were quantified through oscillatory shear rheology and tensile testing. The reported approach provides a general method for post-gelation tuning of mechanical properties using metals and well-defined catenane topologies as part of a network architecture.

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Numerical Study on Mechanical Properties of Quasi-Continuous SiCp/Al Network Composites with Various Particle Size Ratios (PSRs)

International Journal of Applied Mechanics ◽

10.1142/s1758825119500650 ◽

2019 ◽

Vol 11 (07) ◽

pp. 1950065 ◽

Cited By ~ 2

Author(s):

Xiang Gao ◽

Xuexi Zhang ◽

Aibin Li

Keyword(s):

Mechanical Properties ◽

Particle Size ◽

Yield Strength ◽

Network Architecture ◽

Numerical Study ◽

Reinforcement Particle ◽

Load Direction ◽

Network Parameter ◽

Element Analysis ◽

Premature Failure

Recent works verified that network reinforcement design enhanced the modulus and strength of discontinuously reinforced metal–matrix composites (MMCs). The particle size ratio (PSR), i.e., the ratio of matrix to reinforcement particle diameters, defines the particle clustering degree and is an important network parameter. The effects of PSR on the mechanical properties of network SiCp/Al composites were studied via finite element analysis. The results showed that the composites with PSR [Formula: see text]:1 exhibited similar mechanical property. In contrast, composites with PSR [Formula: see text]:1 showed enhanced modulus (87.5–89.5[Formula: see text]GPa) and yield strength (303–315[Formula: see text]MPa) over homogeneous composites (modulus 75.9[Formula: see text]GPa and yield strength 299[Formula: see text]MPa). The enhanced mechanical properties were attributed to the higher load-bearing capacity of the reinforcement walls parallel to the load direction (PaW). However, premature failure and thus reduced elongation occurred with PSR [Formula: see text]:1 because network layers perpendicular to the load direction (PeW) acted as crack propagation paths. So, a threshold PSR of 7:1–8:1 was proposed for effective network design. The sacrifice of elongation needs to be solved for optimized network architecture designs.

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Swelling Behavior and Mechanical Properties of Chemically Cross-Linked Gelatin Gels for Biomedical Use

Journal of Biomaterials Applications ◽

10.1177/088532829901400204 ◽

1999 ◽

Vol 14 (2) ◽

pp. 184-191 ◽

Cited By ~ 35

Author(s):

Xia Lou ◽

Traian V. Chirila

Keyword(s):

Mechanical Properties ◽

Swelling Behavior ◽

Gelatin Gels

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Synergistic Effect of Carbon Nanotubes and Graphene on Diopside Scaffolds

BioMed Research International ◽

10.1155/2016/7090635 ◽

2016 ◽

Vol 2016 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

Tingting Liu ◽

Ping Wu ◽

Chengde Gao ◽

Pei Feng ◽

Tao Xiao ◽

...

Keyword(s):

Mechanical Properties ◽

Carbon Nanotubes ◽

Tissue Engineering ◽

Network Architecture ◽

Body Fluid ◽

Degradation Rate ◽

Synergetic Effect ◽

Cell Culturing ◽

3D Network ◽

The Matrix

A synergetic effect between carbon nanotubes (CNTs) and graphene on diopside (Di) scaffolds was demonstrated. 3D network architecture in the matrix was formed through the 1D CNTs inlaid among the 2D graphene platelets (GNPs). The mechanical properties of the CNTs/GNPs/Di scaffolds were significantly improved compared with the CNTs/Di scaffolds and GNPs/Di scaffolds. In addition, the scaffolds exhibited excellent apatite-forming ability, a modest degradation rate, and stable mechanical properties in simulated body fluid (SBF). Moreover, cell culturing tests indicated that the scaffolds supported the cells attachment and proliferation. Taken together, the CNTs/GNPs/Di scaffolds offered great potential for bone tissue engineering.

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