Identification of Rubber polymer
Needed Glassware
Hard glass Tube,Bent glass tube with cork stopper, Test tube
Hard glass Tube,Bent glass tube with cork stopper, Test tube
Required chemical Reagents:-
Solution I –
Dissolve 1.0 g of p-dimethylamine benzaldehyde and 10 mg of hydroquinone in 100 ml of methanol. Add 10 ml of ethylene glycol and 5 ml of concentrated hydrochloric acid. Dilute the reagent with methanol to obtain relative density of 0.85 at 25°C.
Solution II –
Dissolve 2.0 g of sodium citrate crystals 200 mg of citric acid and 30 mg each of indicators bromocresol green and metanil yellow in 500ml of water.
Procedure –
Place 0.5 to 2.0 g of sample in a hard glass tube equipped with a bent glass condensing tube of about 4 mm bore by means of cork stopper. Heat the test tube on a Bunsen burner. When the sample starts decomposing immerse the other end of condensing tube into a test tube containing Solution II. If a red colour develops then it confirms
polychloroprene rubber. If no colour change is observed then pass the vapours into Solution I and note the colour change. Then add 5 cm3 of methanol and heat on a water bath and note if there is any colour change. shown in pic.
Burning Testing
Reference:- IS 3400 part 22