Table I. Anhydride Analyses by the Morpholine Method Bis-4 -az+Brilliant
.\nh)dnde
Acetic Phthalic
Succinic Itaconic
oA
AnIqdridL
98.27 98.17 95.44 95.47 90.77 90.44 97.31 97.17 97.20 97.21
Yel!o!v
Dimetli)! Yelloi.-\ieth)!enr
.2cid
1.54 1.54 4.45 4.45 9.42 9.42 2.34 2.34 2.34 2.34
Total
.Anhydride
99.71 99.61 99.99
98.53 98.28 95.21 95.34 90.3 5 90.44 97-85 97.80 97.99 97.46
100.02 100.19 99 .a6 99.65 99.51 99.54 99.55
moreover, the visual sharpness of the bis-&azo transition enhances its use as a replacement for dimethyl yellow. The bis-4-azo-brilliant yellow mixed indicator is currently being evaluated by ASTM Committee E-15 as a substitute for dimethyl yellow in E-435-74, Acetic Anhydride Assay Method (3). ACKNOWLEDGMENT The capable assistance of E. J. Taylor, who performed most of the experimental work, is gratefully recognized.
Blue
Total
\
