1、 FORD LABORATORY TEST METHOD EU-AU 050-02 Date Action Revisions 2000 08 30 Revised Editorial no technical change A. Cockman 2000 05 18 Edi torial no technical change A. Cockman 1993 01 04 Printed copies are uncontrolled Page 1 of 4 Copyright 2000, Ford Global Technologies, Inc. DETERMINATION OF CHLO
2、RINE CONTENT OF HIGH FREQUENCY ADHESIVES Application This procedure is used to determine the percentage of chlorine in PVC copolymer high frequency adhesives based on solid content. The material under test is volatilized by heating in an oxygen stream and totally burnt in an oxyhydrogen flame. The c
3、ombustion products are absorbed 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 potenti
4、ometric titration a combined comparison electrode (Ag - AgCl) is required. (Reference solution KNO 3 saturated.) Magnetic Agitator and Stirring Rods Measuring Flasks 100 mL Beakers 250 mL Burettes 25 mL Fish Tail Burner Vacuum Pump Analytical Balance Quartz Combustion Boats FORD LABORATORY TEST METH
5、OD EU-AU 050-02 Page 2 of 4 Copyr ight 2000, Ford Global Technologies, Inc. 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) Condition
6、ing and Test Conditions All test values indicated herein are based on material conditioned in a controlled atmosphere of 23 +/ - 2 C a nd 50 +/ - 5 % relative humidity for not less than 24 h prior to testing and tested under the same conditions unless otherwise specified. Procedure 1. Weigh a specim
7、en of adhesive in a quartz boat to the nearest .1 mgf. The weight of the specimen used i s based on the chlorine content of the adhesive and must be chosen as follows: Approximately 25 mgf at 30 - 60 % Cl by weight Approximately 50 mgf at 10 - 30 % Cl by weight Minimum 100 mgf at 1 - 10 % Cl by weig
8、ht 0.5 - 3 g at below 1 % Cl by weight 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 locked with the ground glass joi nt (E) and the cock (F) opened. 3
9、. 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 burner (B) is ignited. The oxygen flow rate should be 1000 1/h
10、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 sequence is adjusted to 3 4 drops/s for chlorine traces and to 7
11、 - 8 drops/s for a higher chlorine content. FORD LABORATORY TEST METHOD EU-AU 050-02 Page 3 of 4 Copyr ight 2000, Ford Global Technologies, Inc. 7. After the cock (F) is closed the flow rate of oxygen in the gasifying chamber is adjusted to 200 1/h for substances with low carbon content, and for sub
12、stances with high carbon content of 600 1/h. To volatilize the material under test the gasifying chamber is heated from outside using the fish tail burner. The normal time for vol atilizing is approximately 2 minutes. Note: If the oxyhydrogen flame of the burner does not burn free of soot or the fla
13、me does not fill the combustion chamber, the flow rate of oxygen must be adjusted. 8. After combustion is complete, the fish tail bur ner is turned off, the quartz boat is removed and the cock (F) of the ground glass joint opened with the ground - in stopper (E) inserted. 9. Any specimen particles r
14、etained in the gasifying chamber are to be flushed into the oxyhydrogen flame by spraying s everal times with distilled water. 10. The absorption solution intake valve (S) and cock between the measuring flask and the receiver are closed. The measuring flask is removed and a new flask is attached for
15、 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 acidified with the 20 % sulphuric acid to pH2 and is titrated
16、 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 AgNO 3 solution (blank value). Evaluation The chlorine content in percent by weight is calculated as follows : Chlorine (% weight) = 0.709 x (A - B) x 100
17、 W Where: A = Original titration value of 0.02 Normal AgNO 3 in mL. B = Blank titration value of 0.02 Normal AgNO 3 in mL. W = Weight of specimen in mfg. Note: In case of unforeseen difficulties, e. g., fracture of the apparatus, the hydrogen valve must be instantly closed. Chemicals, materials, par
18、ts, and equipment referenced in this document must be used and handled properly. Each party is responsible for determining proper use and handling in it s facilities. FORD LABORATORY TEST METHOD EU-AU 050-02 Page 4 of 4 Copyr ight 2000, Ford Global Technologies, Inc. DETERMINATION OF COATING WEIGHT
19、OF HIGH FREQUENCY ADHESIVES A. Gasifying Chamber S. Absorption Solution Intake Valve B. Burner for combustion of the VM. Vacuum Gauge volatilized specimen E. Ground Class Joint VP. Vacuum Pump F. Stop Cock R. Check Valve C. Combustion Chamber St. Flowmeter W. Cooling Water WB. Wing Burner D. Absorption Vessel
