Barbieri Thesis - BioMedical Materials program (BMM)

Chapter 4 – Conntrol
of mechanical
and degraddation
properties s in composites
4.3. Resuults
4.3.1. Characterizationn
of apatite
XRD showwed
that the ssynthesized
powder p is a caalcium
phosph hate apatite (F Figure 2a)
with similarities
to hydrroxyapatite
ref ference (i.e. JCCPDS
9–432) ). Using CR (F Figure 2b,
Table 2) wwe
observed tthat
the synthe esized apatitee
had all the ch haracteristic vibrational v
bands forr
a calcium phhosphate
apat tite. Needle–liike
apatite particles
measuring
300–
400 nm inn
length and 220–40
nm in width w were seeen
with TEM (F Figure 2c).
4.3.2. Characterizationn
of composites
XRD andd
CR patternss
showed tha at, when the ffiller
content increased, there
were
corresponnding
increasees
in the inten nsity of the appatite
peaks while w the char racteristic
peaks of the copolymeer
decreased (Figure 2a,b; Table 2). The ese observations
were
supportedd
by the effecctive
apatite contents c meassured
with burn
test (Table 1). 1
Figure 2. ( a) XRD and (b) CR spectra for unsintered u apatitte,
M0, M25 and M50. The rectangles
in (a)
represent XXRD
peaks for aapatite
(continuou us line) and coppolymer
(dotted li ine) respectively.
Stars and
filled circless
in (b) represeent
apatite and copolymer c CR ppeaks
respective ely. (c) TEM pic cture of the
synthesizedd
unsintered apattite.
These ressults
demonsttrated
that we introduced innto
the copolym mer amounts of apatite
close to those expeccted
(i.e. 0, 25 and 50% %wt. apatite; M0, M25 and a M50
respectiveely).
Images ttaken
with TE EM and BSEMM
showed that t apatite partic cles were
uniformly distributed inn
the polymer matrix, with nno
agglomerat tes or voids (F Figure 3).
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