Penentuan secara Potentiometric Angka Epoxy

Peralatan
Potentiometer = 751 GPD Titrino / Titroprocessor
Electrodes = 6.0430.100 Ag Titrode; input 1

Pereaksi
c(HClO4) = 0.1 mol/L; D0

Sample
app. 0.2 g UHU resin
25 mL c(TBA) = 0.2 mol/L in acetic acid
TBA = Tetrabutyl ammonium bromide

Remarks
Determination reaction:
O OH
R-CH-CH-R’ + H+ → [R-CH-CH-R’]+
OH OH
[R-CH-CH-R’]+ + Br - → R-CH-CH-R’
Br
Calculations:

Epoxy.No=EP1*C01*C02*C03/C00;3;

Epoxy.No = epoxy number, number of epoxide groups per 100 g of sample
C01 = factor for conversion mL L (0.001)
C02 = concentration of titrating agent (0.1 mol/L)
C03 = factor for 100 g of sample (1000)
Stir sample in solvent during 3 minutes before titration


Answer

Epoxy.No = 8.828 x 0.001 x 0.1 x 1000 / 0.2261 = 0.390

EP1 = 8.828 mL
C00 = 0.2261 g

Literature
I. Gyenes, “Titrationen in nichtwässrigen Medien“
Ferdinand Enke Verlag, Stuttgart (1970), p. 598