DETERMINATION OF COTTON/VISCOSE BLEND:
PROCEDURES
STEP 1: PREPARE SODIUM ZINCATE SOLUTION BY TAKING AN EQUIVALENT OF 180GM OF
SODIUM HYDROXIDE AND DISSOLVING IT IN 180-200ML OF WATER IN A BEAKER. TO THIS,
ADD WITH CONSTANT STIRRING 80 GM OF ZINC OXIDE. HEAT THE CONTENTS IN THE BEAKER
TO ALMOST BOILING UNTIL CLEAR OR SLIGHTLY TURBID SOLUTION APPEARS. COOL, ADD
ABOUT 200ML WATER, STIR THOROUGHLY AND MAKE UP TO 500ML WITH WATER
STEP 2: TAKE A TEST SPECIMEN OF ABOUT 2GM AND DETERMINE THE OVEN DRY MASS
OF IT BY PUTTING ON A CONDITIONING CABINET AT 105±3 DEG CENTRIGRADE FOR 3 HOURS
STEP 3: CUT THE REPRESENTATIVE SAMPLE INTO SMALL PIECES AND PUT IT INTO A
BEAKER.
STEP 4: DILUTE 100ML OF SODIUM ZINCATE SOLUTION WITH 200ML OF DISTILLED
WATER AND MIX THOROUGHLY. ADD THE DILUTED SOLUTION OF SODIUM ZINCATE TO THE
BEAKER AND SHAKE THE CONTENTS OF THE BEAKER VIGOROUSLY, AT INTERVALS, FOR 20
MINUTES
STEP 5: DECANT THE LIQUID THROUGH A NYLON FILTER CRUCIBLE. ADD ABOUT 200ML
DILUTE AMMONIA SOLUTION TO THE RESIDUE IN THE BEAKER AND SHAKE THE CONTENTS FOR
5MINUTES AND AGAIN FILTER
STEP 6: WASH THE RESIDUE WITH DILUTE ACETIC ACID SOLUTION.
STEP 7: ADD WATER TO THE RESIDUE IN THE BEAKER, SHAKE AND TRANSFER THE
SOLUTION AND THE RESIDUE TO THE NYLON FILTER GLASS. WASH OUT ANY REMAINING
FIBRES IN THE BEAKER WITH MORE WATER AND FILTER THE WASHINGS THROUGH THE NYLON
FILTER CRUCIBLE
STEP 8: DRY THE RESIDUE AT 105±3 DEG CENTRIGRADE AND DETERMINE THE OVEN
DRY
MASS
OF THE RESIDUE
CALCULATIONS:
W=
OVEN DRY WEIGHT OF THE SAMPLE
F
= OVEN DRY WEIGHT OF THE RESIDUE
P
= PERCENTAGE BY WEIGHT OF VISCOSE FIBRE
= (W - F) X 100
W
