Investigation of tribological properties of HEMA-based cryogels as potential articular cartilage biomaterials

ABSTRACT

Tribology is one of the most important issues for the repair and regeneration of living tissues in the human body, as it deals with the wear, lubrication, and friction of interrelated surfaces. Hydrogels show potential as cartilage regeneration agents due to their biocompatibility and behave similarly to the lubricating mechanisms found in cartilage tissue. Cryogels, which are included in the class of hydrogels, are more stable than hydrogels in terms of mechanical strength, and references to the tribological properties of these polymers in the literature have been minimal so far. In this study, poly(HEMA-N-vinyl formamide) (poly(HEMA-NVF) and poly(HEMA-N-vinylpyrrolidone) (poly(HEMA-NVP) cryogels with improved hydrophilic properties were synthesized with pure poly(HEMA) cryogel. The swelling properties of HEMA-based cryogels were examined under the heading of various parameters, and their physicochemical characterizations were characterized via FTIR, SEM, mercury intrusion porosimetry, elemental analysis (EDX), and TGA methods. Before investigating tribological properties, a cytotoxicity test was performed for all cryogels. Then, in line with the study’s primary purpose, the tribological properties of cryogels were examined. Abrasion tests were carried out on a pin-on-disc tester linked with ASTM G99-05 standard. According to the results, the friction coefficient of poly(HEMA-NVF) and poly(HEMA-NVP) cryogels is 21.62% and 10.51% higher than poly(HEMA) cryogel, respectively. In addition, the results of abrasion and 3D surface topography images prove that the poly(HEMA-NVP) cryogel wears less and its surface is less deformed than other cryogels.

Graphical Abstract

KEYWORDS:

• Cryogel
• friction coefficient
• wear rate
• wear resistance

Disclosure statement

The authors have declared no conflict of interest.

Additional information

Notes on contributors

Koray Şarkaya

Gülşah AKINCIOĞLU received her Ph.D. degree in Machine Engineering from Duzce University, Turkey, in 2018. Dr. Gülşah Akıncıoğlu works as a faculty member in the Machine Design Department of Gümüşova Vocational School in Düzce University. He has worked on brake pads, cryogenic treatment, Manufacturing and Engineering, Traditional and Non-Traditional Manufacturing Methods, Machinability. He also has many international and national articles papers in Engineering Sciences.

Gülşah Akıncıoğlu

Koray Şarkaya received his Ph.D. degree in Biochemistry from Hacettepe University in Ankara, Turkey. Currently, Koray Şarkaya is an Assistant Professor of Biochemistry Department at Pamukkale University, where he is conducting research activities in Biochromatography, Affinity techniques, and Polymer Science.

Sıtkı Akıncıoğlu

Sıtkı Akıncıoğlu received his Ph.D. degree in the Department of Machine Engineering, Karabuk University, Turkey, in 2015. He has been working as a lecturer (Assoc. Prof. Dr.) in Duzce University, Gümüşova Vocational School, Mechanical Design Department in Turkey since 2008. He has many studies in the field of Mechanical Engineering. His research interests include cryogenic treatment, brake pads, modern manufacturing, friction, wear, and machine design.