Mechanical
Properties of Porous β‑Tricalcium Phosphate Composites
Prepared by Ice-Templating and Poly(ε-caprolactone) Impregnation
Stefan Flauder
Roman Sajzew
Frank A. Müller
10.1021/am507333q.s002
https://acs.figshare.com/articles/media/Mechanical_Properties_of_Porous_Tricalcium_Phosphate_Composites_Prepared_by_Ice_Templating_and_Poly_caprolactone_Impregnation/2215987
In
this study ceramic scaffolds of the bioresorbable and osteoconductive
bioceramic β-tricalcium phosphate (β-TCP) were impregnated
with the bioresorbable and ductile polymer poly(ε-caprolactone)
(PCL) to investigate the influence of the impregnation on the mechanical
properties of the porous composites. The initial β-TCP scaffolds
were fabricated by the ice-templating method and exhibit the typical
morphology of aligned, open, and lamellar pores. This pore morphology
seems to be appropriate for applications as bone replacement material.
The macroporosity of the scaffolds is mostly preserved during the
solution-mediated PCL impregnation as the polymer was added only in
small amounts so that only the micropores of β-TCP lamellae
were infiltrated and the surface of the lamellae were coated with
a thin film. Composite scaffolds show a failure behavior with brittle
and plastic contributions, which increase their damage tolerance,
in contrast to the absolutely brittle behavior of pure β-TCP
scaffolds. The energy consumption during bending and compression load
was increased in the impregnated scaffolds by (a) elastic and plastic
deformation of the introduced polymer, (b) drawing and formation of
PCL fibrils which bridge micro- and macrocracks, and (c) friction
of ceramic debris still glued together by PCL. PCL addition also increased
the compressive and flexural strength of the scaffolds. An explanatory
model for this strength enhancement was proposed that implicates the
stiffening of cold-drawn PCL present in surface flaws and micropores.
2015-01-14 00:00:00
energy consumption
lamellar pores
Composite scaffolds show
PCL addition
plastic contributions
damage tolerance
compression load
plastic deformation
Mechanical Properties
TCP
pore morphology
impregnated scaffolds
failure behavior
strength enhancement
PCL fibrils
polymer
bone replacement material
surface flaws