High lubricity meets load capacity: cartilage mimicking bilayer structure by brushing up stiff hydrogels from subsurface
File(s)
Accepted version
Author(s)
Type
Journal Article
Abstract
Natural articular cartilage has ultralow friction even at high squeezing pressure. Biomimicking cartilage with soft materials has been and remains a grand challenge in the fields of materials science and engineering. Inspired by the unique structural features of the articular cartilage, as well as by its remarkable lubrication mechanisms dictated by the properties of the superficial layers, a novel archetype of cartilage‐mimicking bilayer material by robustly entangling thick hydrophilic polyelectrolyte brushes into the subsurface of a stiff hydrogel substrate is developed. The topmost soft polymer layer provides effective aqueous lubrication, whereas the stiffer hydrogel layer used as a substrate delivers the load‐bearing capacity. Their synergy is capable of attaining low friction coefficients (order 0.010) under heavily loaded conditions (order 10 MPa contact pressure) in water environment, a performance incredibly close to that of natural articular cartilage. The bioinspired material can maintain low friction even when subjected to 50k reciprocating cycles under high contact pressure, with almost no wear observed on the sliding track. These findings are theoretically explained and compounded by multiscale simulations used to shed light on the mechanisms responsible for this remarkable performance. This work opens innovative technology routes for developing cartilage‐mimicking ultralow friction soft materials.
Date Issued
2020-09-24
Date Acceptance
2020-06-01
Citation
Advanced Functional Materials, 2020, 30 (39)
ISSN
1616-301X
Publisher
Wiley
Journal / Book Title
Advanced Functional Materials
Volume
30
Issue
39
Copyright Statement
© 2020 Wiley‐VCH GmbH. This is the peer reviewed version of the following article, which has been published in final form at https://onlinelibrary.wiley.com/doi/10.1002/adfm.202004062. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.
Sponsor
Engineering & Physical Science Research Council (EPSRC)
Grant Number
EP/N025954/1
Subjects
Science & Technology
Physical Sciences
Technology
Chemistry, Multidisciplinary
Chemistry, Physical
Nanoscience & Nanotechnology
Materials Science, Multidisciplinary
Physics, Applied
Physics, Condensed Matter
Chemistry
Science & Technology - Other Topics
Materials Science
Physics
high load-bearing
hydrogels
low friction
polymer brushes
subsurface polymerization
HIGH MECHANICAL STRENGTH
DOUBLE-NETWORK HYDROGELS
ARTICULAR-CARTILAGE
FRICTION
LUBRICATION
POLYMER
SOFT
COMPRESSION
TOUGHNESS
REPAIR
02 Physical Sciences
03 Chemical Sciences
09 Engineering
Materials
Publication Status
Published
Article Number
ARTN 2004062
Date Publish Online
2020-08-02