Polymerization Kinetics Lab Manual
Set-up
1.) Set paraffin oil baths to desired temperature, two hours before the start
of lab.
2.) Dry molecular sieves in oven for 15 minutes.
Methyl Methacrylate Preparation
1.) Weigh out 1.2g sodium hydroxide (NaOH).
2.) Combine NaOH with 600mL distilled water (H2O) in a 1000mL flask.
3.) Measure out 600mL methyl methacrylate (MMA) underneath fume
hood.
4.) In inverted flask with stopcock closed, add the 600mL MMA.
5.) Add 200mL of the NaOH solution to the inverted flask.
6.) Shake thoroughly for a minute. (prevent leaking)
7.) Allow mixture to separate into an organic and aqueous phases.
8.) Decant the aqueous phase out the bottom.
9.) Follow steps 5-8 two more times.
10.) Add about 2g molecular sieve to the inverted flask.
11.) Shake for a few minutes.
12.) Use a Buchner funnel, with filter paper and pour MMA solution
over the filter paper to filter out the molecular sieve.
13.) Store solution in refrigerator.
Butyl Methacrylate Preparation
1.) Same method as set forth for preparation of methyl methacrylate.
Run Solutions (follow these steps for different runs perform under hood)
1.) Determine the monomer solution to solvent ratio you want (i.e. 80:20)
2.) Measure out MMA solution and solvent according to the desired ratio.
The sum of the two volumes should sum to 70mL. (i.e. for 80:20 ratio,
56mL MMA solution, 14mL solvent)
3.) Combine MMA and solvent in 250mL beaker.
4.) Measure out the desired amount of initiator and add to solution.
(For example: For 2g/L initiator, add 0.140g for bulk polymerization,
0.112g for 80:20 ratio.).)
5.) Add magnetic stirrer and mix thoroughly.
6.) For preparation of butyl methacrylate the steps are the same.
Dilatometer filling
1.) Attach vacuum hose to short end of dilatometer.
2.) Open dilatometer stopcock.
3.) Place long end in run solution beaker.
4.) Turn on vacuum pump.
5.) Suck solution up until reaction bulb is filled. (When using Benzoyl
Peroxide initiator and MMA, more air bubbles will be present, so run
solution through dilatometer until most of air is sucked through.)
6.) Close stopcock and turn off vacuum pump at same time.
Experimental runs
1.) Placed filled dilatometer in paraffin oil bath.
i. Make sure reaction bulb is completely submerged.
2.) Use rubber band and paper towel to absorb overflowing solution.
i. Allow paper towels to dry underneath hood before discarding.
3.) Set cathetometer to 40cm and line up cross hairs to the dilatometer.
4.) Once meniscus reaches cross hairs start stopwatch.
i. Make sure to use a stopwatch with splits.
5.) Move cathetometer to 39 cm.
6.) When meniscus reaches crosshairs record time.
7.) Do this until meniscus drops to 9 cm.
8.) Remove dilatometer from bath and wipe off oil from sides.
Polymer isolation/ dilatometer clean up (PMMA)
(Polymer solution may be stored in refrigerator if time does not permit this step)
9.) Attach vacuum hose to Erlenmeyer flask with drilled cap.
10.) Attach hose from cap to short end of dilatometer.
11.) Turn vacuum on and collect solution in flask.
12.) Once all is sucked out, transfer solution into 200mL beaker in ice
bath to stop reaction.
13.) Add about 50mL cyclohexane to solution in ice bath to precipitate
out poly(methyl methacrylate) (PMMA).
14.) Let sit for 10 minutes in ice bath.
15.) Immediately clean dilatometer to prevent clogging.
Clean by doing successive runs through dilatometer with acetone, acetone,
water and acetone.
16.) Take solution and filter out PMMA using filter paper and Buchner
funnel (should look like a gooey wad).
17.) Take filtered out PMMA and dissolve it in 50mL of a common
solvent (toluene).
18.) In large beaker add about 150mL methanol and stir with magnetic
stirrer.
19.) Continuously drop about 30mL of PMMA solution into methanol.
20.) PMMA should precipitate out in white powder like flakes
(marshmallow looking wad with B.P. and MMA).
21.) With filter and small Buchner funnel, filter the PMMA out of the
methanol.
22.) Scrape off the PMMA from the filter paper and add to vial.
Polymer isolation/ dilatometer clean up (PBMA)
9.) Attach vacuum hose to Erlenmeyer flask with drilled cap.
10.) Attach hose from cap to short end of dilatometer.
11.) Turn vacuum on and collect solution in flask.
12.) Once all is sucked out, transfer solution into 200mL beaker in ice
bath to stop reaction.
13.) Add about 30ml of methanol to precipitate out the polybutyl
methacrylate
14.) Let sit in ice for ten minutes
15.) Immediately clean dilatometer to prevent clogging.
16.) Clean by doing successive runs through dilatometer with acetone,
acetone, water and acetone.
17.) Take solution and filter out PMMA using filter paper and Buchner
funnel (should look like a gooey wad).
18.) Take filtered out PMMA and dissolve it in 50mL of a common
solvent (toluene).
19.) In large beaker add about 150mL methanol and stir with magnetic
stirrer.
20.) Continuously drop about 30mL of PMMA solution into methanol.
PMMA should precipitate out in white powder like flakes
(marshmallow looking wad with B.P. and MMA).
21.) With small Buchner funnel and filter paper cut to the size of the
funnel, filter the PMMA out of the methanol.
22.) Scrape off the PMMA from the filter paper and add to vial.
Gel Permeation Chromatography (GPC)
1.) First weigh out approximately 1mg of the polymer.
2.) Place sample in a new vial and add about 1mL of tetrahydrofuran
(THF) for every 0.1mg of polymer.
3.) Next add about 0.1L of toluene for every 2.5mL of the solution. This
serves as a reference value in the refractive index reading.
4.) Allow the sample to completely dissolve.
5.) Take about 0.5mL of the sample and inject it into the GPC.
6.) Take computer detection results as data.
Cleanup
1.)
2.)
3.)
4.)
Clean all glassware with acetone and dry.
Do NOT clean any glassware that has touched MMA in the sink.
Discard of all waste in labeled waste bottle.
Allow paper products, filter paper, etc to dry under hood before
disposing.
5.) Empty collection container from vacuum into labeled waste container.
6.) Turn off oil baths and lights.
Complete List of References
Bicerano, Jozef. Prediction of Polymer Properties (2nd Ed.). New York: Marcel Dekker,
Inc., 1996.
Biesenberger, Joseph A., Sebastian, Donald H. Principles of Polymerization
Engineering. Malabar, FL: Krieger Publishing Company, 1993. p. 716
Brandup, J., Immergut, E.H. Polymer Handbook (2nd Ed.). New York: John Wiley &
Sons, 1975. pp. II-105,106
Brar, A. S. and G. S. Kapur, “Sequence Determination in Methyl Methacrylate - n - Butyl
Methacrylate Copolymer by C NMR Spectroscopy,” Polymer Journal vol. 20, no.9 pp
811-817, 1988.
Buback, Michael. “Propagation rate coefficients in free-radical homopolymerizations of
butyl methacrylate and dodecyl methacrylate”. Chem. Phys. 198, 3451-3464
Burnett, G. M., G. G. Cameron, and M. M. Zafar, “Polymerization of Methyl Methacralate in Solution,” European Polymer Journal, 6, 823-830 (1970).
Clouet, G. and P. Corpart, “Studies on Bulk Polymerization of Methacralate. I. Thermal
Polymerization,” J. Polym. Sci. A, 31, 2815-2824 (1993).
Flory, P.J. Principles of Polymer Chem., Cornell Univ. Press, Ithaca (1953).
Fogler, Scott H. Elements of Chemical Reaction Engineering (3rd Ed.). Upper Saddle
River, NJ: Prentice Hall PTR, 1999. p. 367
Krasavina, N.B., R. A. Navolokina, and YE. N. Zil’berman. “Regularities of Initiation of
Deep Polymerization of Methyl Methacrylate using Benzoyl Peroxide,” Polymer
Science USSR, v 26, n4, pp 947-952, 1984.
Laurence, R.L., Ross, R.T. Continuous Polymerization Reactors, AICHE, New York,
1976
Odian, G. Principles of Polymerization, Wiley, New York (1981).
Ross, Robert T. Jr. and Laurence, Robert L., “Gel Effect and Free Volume in the Bulk
Polymerization of Methyl Methacrylate,” AiChE Symposium Series, v. 72, n.160, p
74-79 (1976).
Rudin, Alfred. The Elements of Polymer Science and Engineering. San Diego:
Academic Press, 1982. pp. 52, 194-198, 208, 210
Seymour, R. B. and C. E. Carraher, Polymer Chemistry: An Introduction, Dekker, New
York (1992).
Wilks, Edward S. Industrial Polymers Handbook. New York: Wiley-VCH, 2001.
http://www.calpoly.edu/~bdillon/Files/MW/mwmw/mwmw.html
http://www.psrc.usm.edu/macrog/pmma.htm
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