Interfacial optimization of fiber-reinforced hydrogel composites for soft fibrous tissue applications

Julianne L Holloway; Anthony M Lowman; Mark R VanLandingham; Giuseppe R Palmese

doi:10.1016/j.actbio.2014.05.004

Interfacial optimization of fiber-reinforced hydrogel composites for soft fibrous tissue applications

Acta Biomater. 2014 Aug;10(8):3581-9. doi: 10.1016/j.actbio.2014.05.004. Epub 2014 May 9.

Authors

Julianne L Holloway¹, Anthony M Lowman¹, Mark R VanLandingham², Giuseppe R Palmese³

Affiliations

¹ Department of Chemical and Biological Engineering, Drexel University, 3141 Chestnut St, Philadelphia, PA 19104, USA.
² US Army Research Laboratory, Aberdeen Proving Ground, MD 21005, USA.
³ Department of Chemical and Biological Engineering, Drexel University, 3141 Chestnut St, Philadelphia, PA 19104, USA. Electronic address: grp27@drexel.edu.

PMID: 24814880
DOI: 10.1016/j.actbio.2014.05.004

Abstract

Meniscal tears are the most common orthopedic injuries to the human body, yet the current treatment of choice is a partial meniscectomy, which is known to lead to joint degeneration and osteoarthritis. As a result, there is a significant clinical need to develop materials capable of restoring function to the meniscus following an injury. Fiber-reinforced hydrogel composites are particularly suited for replicating the mechanical function of native fibrous tissues due to their ability to mimic the native anisotropic property distribution present. A critical issue with these materials, however, is the potential for the fiber-matrix interfacial properties to severely limit composite performance. In this work, the interfacial properties of an ultra-high-molecular-weight polyethylene (UHMWPE) fiber-reinforced poly(vinyl alcohol) (PVA) hydrogel are studied. A novel chemical grafting technique, confirmed using X-ray photoelectron spectroscopy, is used to improve UHMWPE-PVA interfacial adhesion. Interfacial shear strength is quantified using fiber pull-out tests. Results indicate significantly improved fiber-hydrogel interfacial adhesion after chemical grafting, where chemically grafted samples have an interfacial shear strength of 256.4±64.3kPa compared to 11.5±2.9kPa for untreated samples. Additionally, scanning electron microscopy of fiber surfaces after fiber pull-out reveal cohesive failure within the hydrogel matrix for treated fiber samples, indicating that the UHMWPE-PVA interface has been successfully optimized. Lastly, inter-fiber spacing is observed to have a significant effect on interfacial adhesion. Fibers spaced further apart have significantly higher interfacial shear strengths, which is critical to consider when optimizing composite design. The results in this study are applicable in developing similar chemical grafting techniques and optimizing fiber-matrix interfacial properties for other hydrogel-based composite systems.

Keywords: Composite; Hydrogel; Interfacial strength; Meniscus; Poly(vinyl alcohol).

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adhesiveness
Animals
Biocompatible Materials / chemical synthesis*
Biocompatible Materials / therapeutic use
Elastic Modulus
Hardness
Humans
Hydrogels / chemistry*
Hydrogels / therapeutic use
Materials Testing
Polyethylenes / chemistry*
Polyethylenes / therapeutic use
Polyvinyl Alcohol / chemistry*
Polyvinyl Alcohol / therapeutic use
Soft Tissue Injuries / therapy*
Stress, Mechanical
Surface Properties
Tensile Strength

Substances

Biocompatible Materials
Hydrogels
Polyethylenes
ultra-high molecular weight polyethylene
Polyvinyl Alcohol