DRC of Cenex

AIM:
To determine the DRC of Cenex(Concentrated latex.

REAGENTS:

• 2% acetic acid solution
• distilled water.

APPARATUS:

• Cotton waste
• Rubber stopper
• Wash bottle
• 50ml Erlenmeyer flask
• Electronic balance
• 250ml beaker
• Oven
• Glass rod
• Measuring jar

PROCEDURE:

• Shake the sample bottle of latex.
• Transfer 20-25ml of above latex into 50ml Erlenmeyer flask provided with a stopper.

• Weigh about 7-10gm latex in a 250ml beaker.

• Note the weight. A duplicate is also done.
• Add twice the amount of distilled water per gm of latex.

• Add double the amount of 2% acetic acid per gm of latex with constant stirring using a glass rod till the serum gets clear.

• When the serum gets clear, filter through whatman No:1 filter paper
• Thickness of the coagulum is reduced to about 2mm by hand roller.
• Collect any small particles of coagulum from the beaker & filter paper by rubbing with the main bulk.
• Wash the coagulum with running water for atleast 6 changes of water.
• Dry the coagulum at a temperature of 50 degree celsius in an oven for 12 hours.

• If it is not dried uniformly, then pass the coagulum through a mixing mill. Again dry in an oven at 60 degree for1 hour.
• Cool for a while & take the final weight.

• From the weight of the dried film & the initial weight of latex taken, the DRC of Cenex can be calculated.