1、 FORD LABORATORY TEST METHOD EU-AU 050-01 Date Action Revisions 2001 01 31 Revised Editorial no technical change A. Cockman 1993 01 04 Printed copies are uncontrolled Page 1 of 4 Copyright 2001, Ford Global Technologies, Inc. DETERMINATION OF COATING WEIGHT OF HIGH FREQUENCY ADHESIVES Application Th
2、is procedure is used to determine the coating weight in gf/m2 of PVC copolymer based high frequency adhesives applied to cardboards or other material. The material under test is volatilised by heating in an oxygen stream and totally burnt in an oxyhydrogen flame. The combustion products are absorbed
3、 in a receiver. Apparatus and Reagents Required Combustion Apparatus For solid substances. Dr. Wickbold system (see sketch) Type 3. Source: Heraeus - Schott Quarzschmelze GmbH 6450 Hanau Germany pH Meter With glass electrode suitable for pH measurement. For the potentiometric titration a combined co
4、mparison electrode (Ag-AgCl) is required. (Reference solution KNO3 saturated.) Magnetic Agitator and Stirring Rods Measuring Flasks 100 mL Beakers 250 mL Burettes 25 mL Fish Tail Burner Vacuum Pump Analytical Balance FORD LABORATORY TEST METHOD EU-AU 050-01 Page 2 of 4 Copyright 2001, Ford Global Te
5、chnologies, Inc. Quartz Combustion Boats Sodium Hydroxide Solution (NaOH 1 Normal - for absorption. Sulphuric Acid (H2SO4) 20 % by Volume Prepared from 95 - 97 % sulphuric acid. Silver Nitrate Solution (AgNO3) 0.02 Normal. Potassium Pyrosulphate (K2S2O7) Conditioning and Test Conditions All test val
6、ues indicated herein are based on material conditioned in 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. Cut from the coated cardboard at least 5 specimens ea
7、ch 6 - 9 cm2 within +/- 1 mm2. Individually granulate each specimen and spread evenly in a quartz boat. If inorganic substances are present in the adhesive, potassium pyrosulphate must be added to the sample to act as a flux. 2. The quartz boat is inserted in the gasifying chamber (A), the chamber l
8、ocked with the ground glass joint (E) and the cock (F) opened. 3. A 100 mL measuring flask is connected to the combustion apparatus. Open the cock between the combustion apparatus and the measuring flask. 4. Set under a vacuum of 150 - 300 mm mercury. 5. After opening of the cooling water valve, the
9、 burner (B) is ignited. The oxygen flow rate should be 1000 1/h and hydrogen flow rate should be 400 1/h. The length of the oxyhydrogen flame is to be adjusted to approximately 10 cm. 6. The burner (B) is inserted into the ground glass joint and the absorption solution (NaOH) valve opened. The drop
10、sequence is adjusted to 3 4 drops/s for chlorine traces and to 7 8 drops/s for a higher chlorine content. FORD LABORATORY TEST METHOD EU-AU 050-01 Page 3 of 4 Copyright 2001, Ford Global Technologies, Inc. 7. After the cock (F) is closed the flow rate of oxygen in the gasifying chamber is adjusted t
11、o 200 1/h for substances with low carbon content, and for substances with high carbon content of 600 1/h. To volatilise the material under test the gasifying chamber is heated from outside using the fish tail burner. The normal time for volatilising is approximately 2 minutes. Note: If the oxyhydrog
12、en flame of the burner does not burn free of soot or the flame does not fill the combustion chamber, the flow rate of oxygen must be adjusted. 8. After combustion is complete, the fish tail burner is turned off, the quartz boat is removed and the cock (F) of the ground glass joint opened with the gr
13、ound-in stopper (E) inserted. 9. Any specimen particles retained in the gasifying chamber are to be flushed into the oxyhydrogen flame by spraying several times with distilled water. 10. The absorption solution intake valve (S) and cock between the measuring flask and the receiver are closed. The me
14、asuring flask is removed and a new flask is attached for the next test. 11. On completion of the test, the hydrogen, oxygen, vacuum pump and cooling water are turned off, in this order. 12. The contents of the measuring flask are poured quantitatively into the 250 mL beaker. The distillate is acidif
15、ied with the 20 % sulphuric acid to pH2 and is titrated with the 0.02 Normal silver nitrate solution. 13. Carry out a blank combustion test and determine the resultant titration value with 0.02 Normal AgNO3 solution (blank value). Evaluation The amount of adhesive in gf/m2 is calculated as follows:
16、K (gf/m2) = 7.09 x (A - B) x 100 F x C1 Where: A = Original titration value of 0.02 Normal AgNO3 in mL. B = Blank titration value of 0.02 Normal AgNO3 in mL. (1 mL .02 Normal AgNO3 = .709 x 103 grms chlorine.) F = Area of specimen in cm2 (to the nearest sq mm). Cl = Percentage chlorine in the adhesi
17、ve as determined by FLTM EU-AU 50-2. Note: In case of unforeseen difficulties, e.g., fracture of the apparatus, the hydrogen valve must be instantly closed. Chemicals, materials, parts, and equipment referenced in this document must be used and handled properly. Each party is responsible for determi
18、ning proper use and handling in its facilities. FORD LABORATORY TEST METHOD EU-AU 050-01 Page 4 of 4 Copyright 2001, Ford Global Technologies, Inc. DETERMINATION OF COATING WEIGHT OF HIGH FREQUENCY ADHESIVES A. Gasifying Chamber S. Absorption Solution Intake Valve B. Burner for combustion of the VM. Vacuum Gauge Volatilized specimen VP. Vacuum Pump E. Ground Class Joint R. Check Valve F. Stop Cock St. Flowmeter C. Combustion Chamber WB. Wing Burner W. Cooling Water D. Absorption Vessel
