Effect of Polymer Infiltration on the Flexural Behavior of β-Tricalcium Phosphate Robocast Scaffolds

Materials

Francisco J. Martínez-Vázquez¹  Antonia Pajares¹  Fernando Guiberteau¹ 

[1]Department of Mechanical, Energy and Materials Engineering, University of Extremadura, Avda de Elvas s/n., 06006 Badajoz, Spain

关键词: polymer impregnation;    robocasting;    scaffolds;    β-tricalcium phosphate;    bending strength;    toughness;   

DOI  :  10.3390/ma7054001

来源: mdpi

【 摘 要 】

The influence of polymer infiltration on the flexural strength and toughness of β-tricalcium phosphate (β-TCP) scaffolds fabricated by robocasting (direct-write assembly) is analyzed. Porous structures consisting of a tetragonal three-dimensional lattice of interpenetrating rods were impregnated with biodegradable polymers (poly(lactic acid) (PLA) and poly(ε-caprolactone) (PCL)) by immersion of the structure in a polymer melt. Infiltration increased the flexural strength of these model scaffolds by a factor of 5 (PCL) or 22 (PLA), an enhancement considerably greater than that reported for compression strength of analogue materials. The greater strength improvement in bending was attributed to a more effective transfer of stress to the polymer under this solicitation since the degree of strengthening associated to the sealing of precursor flaws in the ceramic rod surfaces should remain unaltered. Impregnation with either polymer also improved further than in compression the fracture energy of the scaffolds (by more than two orders of magnitude). This increase is associated to the extraordinary strengthening provided by impregnation and to a crack bridging toughening mechanism produced by polymer fibrils.

【 授权许可】

CC BY   
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