
56-6 Chemical Variables
program temperature and the actual melting temperature for known melting standards (i.e., mercury,
water, tin, benzoic acid). A penetration probe is used to obtain the onset temperatures for two melting
st
andards
. e tw
o-point
ca
libration
as
sumes
th
e
re
lationship
Eq
uation
56.11 be
tween
th
e
ac
tual
sp
eci-
men
te
mperature
(T
t
) and the observed extrapolated onset temperature (T
0
). S and I are the slopes and
intercept, respectively, in the TMA thermal curve (Figure 56.2):
T T S I
t
= × +( )
0
(56.11)
ermomechanical
me
thods
ar
e
ge
nerally
ap
plied
on so
lid-shaped
sa
mples
li
ke
po
lymeric
pr
oducts
.
Spe
cial
cl
amps
ar
e
us
ed
fo
r
te
st