Biomedical Engineering Reference
In-Depth Information
(vinyl alcohol) used in this work was obtained from Cargill Dow LLC,
Winibest Marketing Ltd, China and from FlukaAG (Switzerland), respec-
tively. All the purchased chemicals used as such. The composite films were
developed using Magic mold releasing agent and with Teflon mold of one
square feet with 3 mm depth. The solvent acetonitrile was purchased from
Rankem and used with purification. Finally the composite films were air
dried in the hot air oven.
9.2.2 MODIFICATION OF CELLULOSE
Cellulose was treated with the saturated sodium hydroxide solution at
room temperature and stirred for 2 hrs. After 2 hrs, solid obtained was fil-
tered off. Salt formation was confirmed by solubility test, since it is freely
soluble in water.
This salt was treated with 2-(Trifluromethyl) benzoylchloride in pres-
ence of pyridine as a base cum solvent and stirred overnight at 100 °C.
Then dumped in to water; solid was filtered off. This product was con-
firmed by IR analysis, which shows the absence of peak at 3332 cm
-1
.
Figure 9.1 represents the IR spectra of cellulose and modified cellulose.
Cellulose Fiber OH + NaOH Cellulose Fiber O
-
Na
+
+ H
2
O
Cellulose Fiber O
-
Na
+
+ R-COCl Cellulose Fiber OCO-R + NaCl
FIGURE 9.1
IR spectras of simple cellulose and modified cellulose.
Search WWH ::
Custom Search