Chemistry Reference
In-Depth Information
treatment time 100 s) enlarges the surface energy to 110 mJ/m
2
and a reduction
is observed to only
65 mJ/m
2
within a fortnight storage time in air environ-
ment. This combination of plasma treatment and ion bombardment reduces aging
effects [163].
The treatment of thin polymer film on the powered electrode in a capacitively
coupled RF discharge (13.56 MHz) leads to changes of its surface properties caused
by modifications of chemical composition. Figure 8.32a represents the IR absorp-
tion spectrum, see Section 7.1 (FTIR-spectroscopy), of a thin LD-PE film with
∼
1.0
0.8
CH (str.)
0.6
LD-polyethylene
Asym.
Sym.
0.4
CH (def.)
0.2
0.0
3500
3000
2500
Wavenumber [cm
-1
]
2000
1500
1000
(a)
6
Oxygen plasma
treatment
(-HC=CH-)
CH
4
C=O
OH (str.)
Functional
groups
2
0
CO,
OH (def.)
-2
Degradation,
etching
-4
3500
3000
2500
Wavenumber [cm
-1
]
2000
1500
1000
(b)
FIGURE 8.32
IR-absorption spectrum of thin polyethylene film (ca. 30 nm) taken by FTIR-
(ATR)-spectroscopy (a) and the ratio spectrum of PE thin film before/after 3 s oxygen (5 Pa)
RF plasma treatment, which provides both the degradation and functionalization of PE (b).
