Polymerization Experiment

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    11-May-2015

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  • 1.Polymerization
    During INTERNSHIP AT MAHIDOL
    Done by: Cindy & Jack

2. Polymerization
Is a process of reacting monomer molecules together reacting in a chemical reaction to form 3-D networks or polymer chains.
3. Monomers & Polymers
MONOMERS are atoms or a small molecule that may bind chemically to other to form polymers.
Polymers are large molecules composed of repeating structural units.
4. Atomic Transfer Radical Polymerization
ATRP is a type of polymerization that can control the length of a polymer
There are 3 components, which includes a monomer, catalyst, and a initiator
5. In this Experiment...
We used Two monomers:

  • Methyl Methacrylate (MMA)

6. StyreneTwo catalysts:
- Copper Bromide (CuBr)
- Liquid TRENFCIM
Two initiator:
- 1-Bromoethylrenzene
- Ethyl 2-Bromoisobuthylate(??)
7. Order of experimentation
Polymerization of MMA
Polymerization of Styrene
Polymerization of MMA and Styrene at the same time
Copolymerization of MMA + Styrene
Copolymerization of Styrene + MMA
- First two were to let us be familiarized with polymerization
8. Purpose
Check whether the theory and the experiment matches or not.
To find out which monomer the catalyst suits more.
To study properties of polymer products and copolymer products
9. Hypothesis
We could have hypothesized, however, we knew nothing about polymerization, so we had no idea what would happen. Therefore,we could not hypothesize.
10. Materials Used
High vacuum
grease
Trap
Parafilm (30)
Argon Gas
Argon (g)
Medium size towel (2)
Stand
Vacuum pump
Thermostat container
Styrene (l)
Ethyl-2-bromoisobuthyl (l)
CuBr (s)
Ligand TRFNFclm (s)
Mask
Aluminum Oxide (s)
Stopper
Column
Cotton
THF
Plastic Spoon
Spatula
short Eyedropper
Long eyedropper
Square Dry Ice (10)
Acetone (l)
Hammer
MMA (l)
Goggles
Weighing papers
Gloves
Magnetic bar
Funnel
Anti-bump
Stirrer
Magnetic stirrer
11. Procedure
The step by steps in the experiment werent complicated but it just took a lot of time and had us ending up like this..
12. Setting Trap
Apply grease to the cap of the trap
Put the trap on the stand
Connect the 2 tubes from the vacuum to the trap
Use parafilm to wrap around the tubes to prevent leakage
Turn on the vacuum machine
Open the argon gas tank
Wait for 30 minutes
Put the trap in a thermostat container
Get dry ice and put it in the container
Once its full, pour acetone in the container slowly
Cover the top with a rag
13. Setting Side-Arm flask
Get a side-arm flask from the oven
Quickly set it on the stand
Adjust the stopper cock onto the flask
Stick the rubber stopper on the opening
Vacuum it for 5 minutes
Change it to argon gas for 20 seconds
Repeat the last two steps 2 more times
14. Weighing Catalyst
Get the catalyst needed from the desiccator
Put the weighing paper in the weighing scale and zero it
Using a spatula get the amount of catalyst needed
Do it again using a different spatula and weighing paper if there are more catalysts
Quickly open the rubber stopper and put the catalysts needed
Vacuum it 3 times
15. Injecting the monomer
Bring out the monomer from the fridge
Store it at room temperature
Get a needle from the oven and stick it on a plastic syringe
Using the needle pump the argon out 3 times
Using the needle with the syringe take 2mL out of the monomer
Using tissue, adjust the amount of monomer needle by flipping the needle backwards
Inject it in the flask
Get a glass stopper from the oven
Apply grease on it
Quickly replace it with the rubber stopper
16. Freeze Pump Thaw
Put the side arm flask in a thermostat container
Add dry ice into the container
Slowly pour in acetone into the container
Wait till the liquid solution freezes
Vacuum it for 10 minutes
Close the valve on the flask
Take the flask out of the container
Leave it for it to melt
After it turns to liquid, put it back in the container
When it freezes, open the valve
Vacuum it for 10minutes
Repeat steps 6~11 again
Close the valve
Take the flask out and let it melt
Change the glass stopper to a rubber stopper before
it melts
17. Stirring
Get a magnetic stirrer
Set the flask on top of it
Place a piece of tissue under the flask
Set it to 300rpm
Stir it for 5minutes
18. Injecting the Initiator
Go to the oven and get needle syringe and a glass bottler(idk how to call)
Get the initiator from the desiccator (1-bromoethylrenzene)
Pour a little bit initiator into the glass bottle
Get the needle and pump the argon out 3 times
Put it in the flask
Move it to the magnetic stirrer with heat ( temperature depends on the catalyst)
Stir it
Add THF to stop the reaction
19. Removing Catalyst
Wear a mask
Get a column with a stopper and fix it on a stand
Put a small piece of cotton in the column enough to block the bottom
Get 20 spoons of aluminum oxide in a beaker
Pour in THF enough to cover the aluminum oxide
Mix it well using
Pour it down the column
Using THF let most of aluminum oxide go in the column
Let all the aluminum oxide on the walls of the column go to the bottom
Hit the column with a tube so that itll be packed
Place a beaker under the column and open the valve
20. Removing Catalyst
When a little bit of THF is left, close the valve
Using a dropper drop THF in the column along the walls
Repeat the steps until the THF in the column is clear
When it gets clear, close the valve
Get the solution in the side arm flask
Using another magnetic bar, take the magnetic bar inside out
Get a long dropper and use it to drop towards the wall of the column
When done, using THF rinse the side arm flask and pour it in the column (twice)
Use a dropper with THF to rinse the walls of the column too
Get a flask and replace it with the beaker under the column
Open the valve, and make it a drop per 2 seconds
Pour THF in the column if the opening near the stopper cock isnt transparent
21. Removing Solvent
Pour the solution in the flask using a funnel into a 250mL round bottom flask
Open the vacuum machine
Set it to 40 degrees
Connect the anti-bump to the machine
Right next to the anti-bump connect the round bottom flask
Close the top(??) to reduce pressure
Lock the anti-bump and the round bottom flask using a blue clip
Rotate it for 20~30 minutes
22. Removing Solvent
Open the top(??) to increase pressure back
Take the blue clip out and take out the round bottom flask
Using a dropper drop 2 droppers of dichloromethane into the round bottom flask
Pour 50mL of methanol into the round bottom flask
Leave it for 5 minutes
Pour the methanol in the round bottom flask out into a beaker
Using a spatula gather all the precipitate in the flask into a ball
Vacuum it for __ hours
23. Results (MMA)
24. Results (styrene)
25. Results (MMA then Styrene)
26. Results (Styrene then MMA)
27. Results (random)
28. Conclusion
To conclude, we had to compare between the theory and the real experiment. We have an answer to this which is that the theorys expected numbers are not same as the ones in the real experiment.In the theory, the polydispersity number should be 1 for all, however, we got 1.3 or even higher, 2. Therefore, we could say that those two things are two different things.
It has been concluded thatthe catalyst we used was more suitable for styrene than mma because in the results the polydispersity of styrene was closer to 1; and others it was more than 1.5 which means the catalyst cant control the process.
29. The polydispersity of MMA was about 1.92 and for Styrene was about 1.3 . According to the theory, they both should have approximately 1.These are the properties that is the most important.
30. A BIG THANKS TO
P Dear for helping us throughout the experiment
P Man for taking us to MahidolSalaya campus
Dr. Ekasith for allowing the internship to Mahidol
& so many other people for helping