Synergistic regulation mechanism of bionic structure and poly (vinylsulfonic acid) sodium (PVSNa) coating for high load bearing lubrication

AbstractSilicone elastomers-based materials have been extensively involved in the field of biomedical devices, while their use is extremely restricted due to the poor surface lubricity and inherent hydrophobicity. This paper describes a novel strategy for generating a robust layered soft matter lubrication coating on the surface of the polydimethylsiloxane (PDMS) silicone elastomer, by entangling thick polyzwitterionic polyelectrolyte brush of poly (sulfobetaine methacrylate) (PSBMA) into the sub-surface of the initiator-embedded stiff hydrogel coating layer of P(AAm-co-AA-co-HEMA-Br)/Fe, to achieve a unified low friction and high load-bearing properties. Meanwhile, the stiff hydrogel layer with controllable thickness is covalently anchored on the surface of PDMS by adding iron powder to provide catalytic sites through surface catalytically initiated radical polymerization (SCIRP) method and provides high load-bearing capacity, while the topmost brush/hydrogel composite layer is highly effective for aqueous lubrication. Their synergy effects are capable of attaining low friction coefficient (COFs) under wide range of loaded condition in water environment with steel ball as sliding pair. Furthermore, the influence of mechanical modulus of the stiff hydrogel layer on the lubrication performance of layered coating is investigated, for which the COF is the lowest only when the modulus of the stiff hydrogel layer well matches the PDMS substrate. Surprisingly, the COF of the modified PDMS could remain low friction (COF < 0.05) stably after encountering 50,000 sliding cycles under 10 N load. Finally, the surface wear characterizations prove the robustness of the layered lubricating coating. This work provides a new route for engineering lubricious silicon elastomer with low friction, high load-bearing capacity, and considerable durability.

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Evaluation of a hybrid scaffold/cell construct in repair of high-load-bearing osteochondral defects in rabbits

Biomaterials ◽

10.1016/j.biomaterials.2005.07.040 ◽

2006 ◽

Vol 27 (7) ◽

pp. 1071-1080 ◽

Cited By ~ 150

Author(s):

Xin Xin Shao ◽

Dietmar W. Hutmacher ◽

Saey Tuan Ho ◽

James C.H. Goh ◽

Eng Hin Lee

Keyword(s):

High Load ◽

Osteochondral Defects ◽

Hybrid Scaffold ◽

Load Bearing

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Synergistic regulation mechanism of selectin and integrin on leukocyte adhesion under shear flow

Journal of Applied Mechanics ◽

10.1115/1.4052367 ◽

2021 ◽

pp. 1-32

Author(s):

Wei Kang ◽

Long Li ◽

Jizeng Wang

Keyword(s):

Shear Flow ◽

Leukocyte Adhesion ◽

Hydrodynamic Process ◽

Regulation Mechanism ◽

Leukocyte Rolling ◽

Cooperative Effects ◽

Inflammatory Site ◽

Synergistic Regulation ◽

Effective Phase ◽

Kinetics Of

Abstract In the process of inflammation, the hydrodynamic process of circulating leukocyte recruitment to the inflammatory site requires the rolling adhesion of leukocytes in blood vessels mediated by selectin and integrin molecules. Although a number of experiments have demonstrated that cooperative effects exist between selectins and integrins in leukocyte rolling adhesion under shear flow, the mechanisms underlying how the mechanics of selectins and integrins synergistically may govern the dynamics of cell rolling is not yet fully resolved. Here we present a mechanical model on selectin- and integrin- jointly mediated rolling adhesion of leukocyte in shear flow, by considering two pairs' binding/unbinding events as Markov processes and describing kinetics of leukocyte by the approach of continuum mechanics. Through examining the dynamics of leukocyte rolling as a function of relative fraction of selectin and integrin pairs, we show that, during recruitment, the elongation of intermittent weak selectin bonds consuming the kinetic energy of rolling leukocyte decelerates the rolling speed and enables the integrin pairs to form strong bonds, therefore achieving the arrestment of leukocyte (firm adhesion). The coexistence of selectins and integrins may also be required for effective phase transition from firm adhesion to rolling adhesion, due to dynamic competition in pairs' formation and elongation. These results are verified by the relevant Monte Carlo simulations and related to reported experimental observations.

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New Approach for Versatile Self Piercing Riveting: Joining System and Auxiliary Part

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.883.3 ◽

2021 ◽

Vol 883 ◽

pp. 3-10

Author(s):

Fabian Kappe ◽

Mathias Bobbert ◽

Gerson Meschut

Keyword(s):

Boundary Conditions ◽

Research Work ◽

High Load ◽

Continuous Increase ◽

New Approach ◽

Load Bearing ◽

Mechanical Joining ◽

Wide Range ◽

Riveting Process

The increasing use of multi-material constructions lead to a continuous increase in the use of mechanical joining techniques due to the wide range of joining possibilities as well as the high load-bearing capacities of the joints. Nevertheless, the currently rigid tool systems are not able to react to changing boundary conditions, like changing the material-geometry-combination. Therefore research work is crucial with regard to versatile joining systems. In this paper, a new approach for a versatile self-piercing riveting process considering the joining system as well as the auxiliary joining part is presented.

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Continuously Growing Ultrathick CrN Coating to Achieve High Load-Bearing Capacity and Good Tribological Property

ACS Applied Materials & Interfaces ◽

10.1021/acsami.7b16426 ◽

2018 ◽

Vol 10 (3) ◽

pp. 2965-2975 ◽

Cited By ~ 25

Author(s):

Zechao Li ◽

Yongxin Wang ◽

Xiaoying Cheng ◽

Zhixiang Zeng ◽

Jinlong Li ◽

...

Keyword(s):

Bearing Capacity ◽

Tribological Property ◽

High Load ◽

Load Bearing Capacity ◽

Load Bearing ◽

Crn Coating

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Synergized high‐load bearing bone replacement composite from poly(lactic acid) reinforced with hydroxyapatite/glass fiber hybrid filler—Mechanical and dynamic mechanical properties

Polymer Composites ◽

10.1002/pc.25807 ◽

2020 ◽

Vol 42 (1) ◽

pp. 57-69

Author(s):

John O. Akindoyo ◽

M.D.H. Beg ◽

S. Ghazali ◽

H‐P. Heim ◽

M. Feldmann ◽

...

Keyword(s):

Mechanical Properties ◽

Lactic Acid ◽

Glass Fiber ◽

Dynamic Mechanical Properties ◽

High Load ◽

Poly Lactic Acid ◽

Hybrid Filler ◽

Load Bearing ◽

Dynamic Mechanical ◽

Bone Replacement

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Structural bionic design for thin-walled cylindrical shell against buckling under axial compression

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406211407820 ◽

2011 ◽

Vol 225 (11) ◽

pp. 2619-2627 ◽

Cited By ~ 5

Author(s):

D Xing ◽

W Chen ◽

J Ma ◽

L Zhao

Keyword(s):

Cylindrical Shell ◽

Axial Compression ◽

Cross Section ◽

Cylindrical Shells ◽

High Load ◽

Vascular Bundles ◽

Bionic Design ◽

Load Bearing ◽

Thin Walled ◽

The Cross

In nature, bamboo develops an excellent structure to bear nature forces, and it is very helpful for designing thin-walled cylindrical shells with high load-bearing efficiency. In this article, the cross-section of bamboo is investigated, and the feature of the gradual distribution of vascular bundles in bamboo cross-section is outlined. Based on that, a structural bionic design for thin-walled cylindrical shells is presented, of which the manufacturability is also taken into consideration. The comparison between the bionic thin-walled cylindrical shell and a simple hollow one with the same weight showed that the load-bearing efficiency was improved by 44.7 per cent.

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