BS ISO 1304:2016 pdf download – Rubber compounding ingredients — Carbon black — Determination of iodine adsorption number
Ordinary laboratory equipment (beakers, funnels, porcelain spoon, weighing bottles, etc.), plus the following:
4.1 Analytical balance, with sensitivities:
a) 0,01 g (for 6.1.5 and 7.3.5);
b) 0,1 mg (for other paragraphs).
4.2 Oven, preferably of the gravity-convection type, capable of temperature regulation to within ±1 °C at 125 °C and temperature uniformity to within ±5 °C.
4.3? Stoppered? one-mark? volumetric? flasks, preferably class A in accordance with ISO 1042, of capacities:
a) 2 000 cm 3 , with a tolerance of ±0,60 cm 3 ;
b) 1 000 cm 3 , with a tolerance of ±0,40 cm 3 .
4.4 Repetitive dispenser, 25 cm 3 capacity, calibrated to within ±0,03 cm 3 accuracy, or one-mark pipettes, high precision, of capacities:
a) 20 cm 3 , with a tolerance of ±0,03 cm 3 ;
b) 25 cm 3 , with a tolerance of ±0,03 cm 3 .
If class A pipettes in accordance with ISO 648 are used, no calibration is necessary. In other cases,pipettes shall be calibrated to the nearest 0,01 cm 3 with distilled water, a temperature correction being made if necessary to show the true delivery at any volume used to within 0,01 cm 3 . The true delivered volume is the read volume plus (or minus) the calibration correction at that volume. For high-precision volume determination (see 7.2.2, 7.3.2, 8.3.3, 8.3.6 and 8.3.8), it is recommended that the 20 cm 3 and 25 cm 3 pipettes have calibration corrections of the same magnitude and in the same sense.
4.5 Digital burettes, with 0,01 cm 3 increment counter and zero-reset control, calibrated to within ±0,05 cm 3 accuracy, or burettes (for method A only), high precision, side-arm filling, graduated in
0,05 cm 3 and with automatic zero, of capacities:
a) 25 cm 3 , with a tolerance of ±0,05 cm 3 ;
b) 50 cm 3 , with a tolerance of ±0,05 cm 3 .
If class A burettes in accordance with ISO 385 are used, no calibration is necessary. In other cases,burettes shall be calibrated to the nearest 0,01 cm 3 with distilled water, a temperature correction being made if necessary to show the true delivery at any volume used to within 0,01 cm 3 . The true delivered volume is the read volume plus (or minus) the calibration correction at that volume.
4.6 Stoppered bottles, with ground-glass stoppers, of capacities 250 cm 3 and 500 cm 3 .
4.7 Glass bottle, with ground-glass stopper, of capacity 2 000 cm 3 .
4.8 Amber-glass bottles, with ground-glass stoppers, of capacities 1 000 cm 3 and 2 000 cm 3
4.9 Centrifuge tubes, of capacity 50 cm 3 , with screw cap and polyethylene liner.
Cork, rubber or metal stoppers shall not be used.
4.10 Mechanical shaker, capable of 240 strokes/min, with 25 mm stroke length.
4.11 Centrifuge, minimum speed 105 rad/s (1 000 r/min).
4.12 Desiccator, with silica gel as desiccant.
4.13 Magnetic stirrers and spin bars.
4.14 Automatic titrator (for method B only), equipped with a combined electrode for potentiometric
Unless otherwise stated, all chemicals shall be of reagent grade.
5.1 Water, deionized or distilled.
5.2 Iodine (I 2 ).
5.3 Potassium iodide (KI).
5.4 Potassium iodate (KIO 3 ).
5.5 Sodium thiosulfate pentahydrate (Na 2 S 2 O 3 ·5H 2 O).
5.6 n-Amyl alcohol (C 5 H 11 OH).
5.7 Sulfuric acid (H 2 SO 4 ), mass fraction 98 %, ρ = 1,84 Mg/m 3 .
5.8 Soluble starch (for method A only).
5.9 Salicylic acid (C 7 H 6 O 3 ) (for method A only).
6 Preparation of solutions
6.1 Iodine solution, 0,023 64 mol/dm 3 (0,047 28 N), containing 9,5 parts of potassium iodide to 1 part of iodine.
NOTE Since the test result depends on the concentration of both iodine and potassium iodide in the solution,the instructions for the preparation and the standardization of the solution (7.3) have to be followed precisely.
6.1.1 Weigh, to the nearest 0,01 g, 114,00 g of potassium iodide (5.3) into a 100 cm 3 beaker.
6.1.2 Place about three-quarters of the KI in a clean 2 000 cm 3 volumetric flask (4.3) through a large diameter funnel.
6.1.3 Add enough water (5.1) to cover the KI. Swirl to dissolve, and allow to stand until the solution attains ambient temperature.
6.1.4 Place the remainder of the KI in a 250 cm 3 beaker with enough water (5.1) to dissolve it.
6.1.5 Weigh, to the nearest 0,01 g, 12,00 g of iodine on the balance [4.1 a)] in a weighing bottle fitted with a ground-glass stopper. Use only a porcelain spoon to transfer the iodine crystals, and close the
weighing bottle when making weighings.
6.1.6 Transfer the iodine through a funnel to the potassium iodide solution prepared in 6.1.3.
6.1.7 Wash thoroughly the weighing bottle with portions of the KI solution prepared in 6.1.4 until no colour remains, and transfer the washings through the funnel to the 2 000 cm 3 volumetric flask.
6.1.8 Wash the funnel with the rest of the KI solution prepared in 6.1.4.
6.1.9 Add water (5.1) to almost fill the volumetric flask, cap it with the ground-glass stopper, invert it 2 or 3 times to homogenize and let it stand for about one hour.
6.1.10 Open the flask, make up to the mark with water (5.1), insert a spin bar in the flask, place it on the magnetic stirrer (4.13) and stir for 2 h at least at medium speed.
At medium speed, the depth of the vortex should be about 5 mm.
6.1.11 Transfer the solution to an amber-glass bottle (4.8) and let it stand overnight prior to any use.