1、 FORD LABORATORY TEST METHOD AO 005-08 Date Action Revisions 2001 01 30 Revised Editorial no technical change A. Cockman 1992 04 30 Printed copies are uncontrolled Page 1 of 2 Copyright 2001, Ford Global Technologies, Inc. ACIDITY OF TOLYLENE DIISOCYANATE Application This is a method for determining
2、 the acidity of tolylene diisocyanate (a compound of high resilient polyurethane foam). Apparatus Required Flask Three 500 mL Erlenmeyer. VWR Catalog No. 29137-120 or equivalent. Buret 10 mL VWR Catalog No. 17452-368 or equivalent. Pipet 20 mL VWR Catalog No. 52967-242 or equivalent. Materials Requi
3、red Bromophenol Blue Eastman Kodak No. 752. n-Propyl Alcohol (n-Propanol) Reagent grade. CAUTION: Low flash point, refer to Fire Control Bulletin No. 18 (1). Methyl Alcohol Reagent grade. CAUTION: Low flash point, refer to Fire Control Bulletin No. 18 (1). Potassium Hydroxide Reagent grade. CAUTION:
4、 Corrosive, refer to Industrial Hygiene Bulletin No. 10. (1) Refer to Industrial Hygiene for health and safety comments. (Industrial Hygiene Field Service, Telephone (313) 33-78955). FORD LABORATORY TEST METHOD AO 005-08 Page 2 of 2 Copyright 2001, Ford Global Technologies, Inc. Solutions Required B
5、romophenol Blue Indicator Add bromophenol blue to methyl alcohol to make a 1 % solution (by volume). Potassium Hydroxide Solution Add potassium hydroxide to methyl alcohol to make a 0.02 N solution. Conditioning and Test Conditions All test values indicated herein are based on material conditioned i
6、n a controlled atmosphere of 23 +/- 2 C and 50 +/- 5 % relative humidity for not less than 24 h prior to testing and tested under the same conditions unless otherwise specified. Procedure 1. Add 5 drops of the 1.0 percent methyl alcohol solution of bromophenol blue indicator to three 500 mL Erlenmey
7、er flasks each of which contain 200 mL of n-propanol. The indicator should give the n-propanol solvent a yellow color. Note: Do not use n-propanol which yields a blue or blue-green color. 2. Neutralize the solvent in each flask to a permanent dark green color using the 0.02 N methyl alcohol - potass
8、ium hydroxide solution. Reserve one Erlenmeyer flask with green-colored solvent as a color comparator (for para 4). 3. Into each of the other two flasks pipet 20 mL of the sample of tolylene diisocyanate and swirl to effect solution. Do not cool the flasks. Allow the reaction mixture to stand for 30
9、 - 40 minutes. CAUTION: Tolylene diisocyanate is classified as a Poison B by the Dept. of Transportation. Refer to Industrial Hygiene for health and safety comments. 4. Titrate with the 0.02 N methyl alcohol - potassium hydroxide solution to the dark green end point (refer to para 2) using a 10 mL s
10、emimicro buret. 5. Calculation: A x N x 3.65 = % acidity by weight (as hydrochloric acid) 24.4 A = mL of N normal KOH required N = Actual normality of the KOH solution Chemicals, materials, parts, and equipment referenced in this document must be used and handled properly. Each party is responsible for determining proper use and handling in its facilities.
