R. P. Quirk1 University of Arkansas Fayeneville 72701
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Macromolecular Chemistry organic An interini course
A variety of subject material has been developed recently for use in interim courses, as illustrated in numerous articles published in this Journal (1,2). However, the topic of macromolecular chemistry has not been developed for use in a short course format. During 1972-1975, a 3-4 week module on organic polymer chemistry has been offered a t the University of Arkansas. This report was written to provide background information, resource material, and a course outline to stimulate chemistry teachers to incorporate analo g material ~ ~ on macromolecular chemistry into their curricula. The main impetus for developing this offering was the realization that, in spite of the fact that a majority of our chemistry graduates go to work for chemical industry involved in polymer production, most undergraduate chemistry students have little, if any, direct contact with macromolecular chemistry. One of the primary objectives of this course was
Table 2. Sample Problem Set Questions 1. Arrange the following polymers i n order of increasing Tmp and explain your order: Nylon 620. Nylon 66, Nylon 610. 2. Describe experimental conditions which could be used t o ore-
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I. Introduction and Hirtoricai 118. 191 A. Colloid Chemirtry. 18bol19io 8. Macromolecular Hypothesis, 1920 ii. Polvmerization Reactinns --. . A. Chain Growth 8. SteD Growth Addition Polymers versus condensation POiY" Ring-Opening Polymerization (20) 111. l e r Synthesis (21-23) PolYcondenration Reactions (Step Grow'th) 1. Esterification (24. 25) 2. Amidation 3. Urethane Svnthesir 176) ,--, 4. Silicone s;htherir (27, 28) Addition Polymerization (Chain Growtt 1. Free Radical (29) 2. Cationic (30) 3. Anionic- ,~ ? I )- - , Ring-Openmg Polymer~zation 1. Cycllc Ethers and EDoxlder (32, 3 3 )
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VI.
VII.
ViII. IX.
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Characterization of Polymers A. Molecular Weight B. Melting Point C. Giarr Transition Temperature (34) Factors Affecting Polymer Propertier A. I 8. Regularity of C h i i n Structure C. Fiexibillty of the Main Chain (35-37) D. Strength of Intermolecular Forcer Structure-Property Reiationmipr (37, 38) A. Homopoiymerr 8. COPOlYmerr 1. Random (R, S and cis-, trans-) 2. lsotactic, Syndiotactic, Atactic 3. Block Copolymers (39, 40) Effects of Branching and Crorrlinking A. Cryrtallinity 8. Flexibilitv C. vulcaniz&n D. Bakelite Plasticizers Bulk Propertie6 of Poiymerr A. Plastic R. .Finer -. .. ..
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C. Rubber (41) ootionai soeeiai Tnair.
L?Thereferences lirted after each topic refer t o citations listed at the end of this paper. These specific references, i n addition t o the general textbooks, should be consulted for each topic.
570 1 J m l of ChemicalEducation
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-~, ~ . . .. . . .. noncrystalline p&y&er; however, the iree-radical po~ymeriration o f 1.1-difiuoroethylene Producer a crystalline polymer. Provide an explanation for the effect o f rubrtituents on this polymer property. 9. Arrange the following linear polymers in order of decreasing crystalline melting point5 ( i f any are permanently amorphous. list them reparatelyl. Explain your order: Atactic oalvoro~
Table 1. Course Outline Far a Macromolecular
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formaldehyde polymerization reaction. 4. What types of polymers are used in latex mints? ~ e s c r i b e briefly the fiim-forming Process far therepaints and &&re this w i t h analogour procerrer for oil-bared paints. 5. What types of reactions can be used t o vulcanize (crors-link) a linear polymer such as polY(dimethylsiloxane)? 6. A polymer is formed by the condensation reaction between maieic anhydride and ethylene glycol. Styrene is then added and polymerized with a free-radical initiator. Describe the
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10. Write structures for the following common polymeric materials Mylar, Bakelite. Lucite. Saran. Orlon, natural rubber. Neoprene. Teflon. SBR rubber, epoxy resins. For each o f there Polymers, suggest methods for their preparation.
to show students that macromolecular chemistrv is an interesting and challenging field which restson thesnme l'oundation of basic chemical principles as do the traditional cheniical areas. More specific courseohjectives were to Provide students with an appreciation for the unique aspects of organic polymer synthesis. 2) Provide students with a hasic understanding of structureproperty relationships for organic polymers. 3) Provide students with the challenge of searching the chemical literature in specific subject areas. Course Structure A lecture-discussion format was found to he quite effective for the relatively small class sizes involved (-10 students1 year). The inherently interesting and ubiquitous nature of polymer chemistry was conducive for lively discussion sessions. At the first class meeting, the students were presented with an overall course outline (see Table 1) and a list of current hooks, journals, and reference articles which were available for each topic. The availability of good reference hooks on polymer chemistry (3-13) and inexpensive paperback hooks (14-17)2 for class use should help both the student and the instructor master the necessarv hackmound information. Midway through the course, the students were given problem sets which were to he completed outside of class and turned in to the instructor for grading. These problem sets were de1)
'Visiting professor, Institute of Polymer ~cience,University of Akron. ,.I ,h t i p pnprrbark hcmksareexperially uvrfulforstudenw and for Instructurs whew spec~alityarea is not polymer ehrrnistrv.
signed to require the students to review classroom material, to utilize the available librarv resources. and to annlv their knowledge and understanding to new areas. The pidbiem set served as one of the nrimarv learnine exneriences for the students. Sample prdhfem sit questions i15) are listed in Table 2 as an indication of the obiectives which can be achieved in this type of course. At thk end of the course, an in-class examination was given t o evaluate each student's achievement. One theme pervaded the entire course: Most of the interesting and basic aspects of polymer chemistry can be grasped by application of relatively simple chemical concepts such as rotational barriers, chiral centers, structural regularity, and intermolecular forces (see item V in Table 1)with which students are alreadv familiar. It is rewardim for both the student and the instrucior to come to this realization Conclusion This hrief description of a short rourse on organic polymer chemistrv should show that it is possible for a non-specialist in polymer chemistry to offer sukh a course. The availability of numerous, quality texts (many in paperback editions) and the interest and enthusiasm of the students for this material will help any instructor to overcome the initial reluctance to develop such a course. I t is strongly recommended that macromolecular chemistry be presented to all undergraduates, either in the format presented herein, or integrated into the regular course material. Literature Clted
included therein. 13) Flory. P. J.. "Principle of Polymer Science," Cornell U~ivemityPress. Ithaca. N.Y.. 1953. 141 Billmeyer. F. W., Jr.. "Tertbmk of Polymer Science," 2nd Ed.. Wilcy-Interwianee. New Yotk, 1971. I51 Lon.. R.W., "Organic Chemistry of Synthetic High Polymers," Wilcy-Interscience, New York. 1967. (61 Seymour, R. B., "lntrduelion to Polymer Chemistry," McCrew-Hill. New Yark, 1 911~ .....
I71 Deanin. R. D.. "Polvmer Structure. Pronortie. and Aoolicationa."Cahners. Boaton.
Rolf, W. J.. Smtt,J. &and Pacitti. J.."Handbook ofCommonPolymers."CRC Press. Cleveland,Ohio 1971. Wiseman, P., "An lntmduction to Industrial Organic Chemistry," Applied Science Publishers, London. 1972. Odian, G., "Principles of Polymerization," McGraw-Hill, New Ymk, I970. Stcvens. M. P., "Polymer Chemistry: An lntrduetior " Addisan-Wesley. Fading, Mass., 1975: also available in paperback. O'Drismll, K. F,"The Nature and Chcmistryof High Pnlgmen,"Reinhold, New York, 1 9fd .....
Alfrey, T.. and Gurnee. E. F., "Organic Polymers," hutice-Hall. Englewood Clilfa, New Jersey, 1967. Treloar, L. R. G., "Introduction to P n l w c r Science." Wykeham Publicafions, London. 1970. Msndelkern, L., "An lntroductlon to Maeromoleeule." Springer-Vcrlsg, New York,
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Sandier. S. R.. and Ksro, W.."Polymer Synthesis," Volume 1, Academic Press, New lWd ............
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Sorsmmn, W. R.. and Campbell.T. W., "Prepsrsfive Mcthdsof PolymerChemi3try," Wiley-Inferscience. New York. 1961. Brown,A. E.,and Reinhart,K.A.,Science, 173.287 119711. Camthem, W. H.. Chem. RPU.,8.353 119311. Bailey. M. E., J.CHEM. EDUC.. 48.809119711. Noll, W.. "Chemistry and Teehnuiagy of Silicone," Academic Press. New York. ,as*
Watt.J. A.C.,Chem. Brit.. 6.519 119701. Morton, M., J. CHEM. EDUC.. 50, 740 119731. Kennedy, J . P.,"Cationie Polymerization ofolefine." Wiley.lntePsience,NewYork, ,976.
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M.. '"Maeromoleeular Science, MTP lntemstianal Review of Science, Physical Chemistry Series One."IEdiLor: Barn. C. E. H J , Univemity Park Pres. Baltimore, Maryland, 1972. Volume 8. pp. 1-48. Dreyluss,P., Chem. Teehnol.. 3,358 (1973). Price. C. C..Ace. Chsm Res., 7.294 119741. J0hari.G.P.. J.CHEM. EDUC.,11,23 119741. Lowe. J . P., Prog Phys. O r g Chem.. 6.111968). Norlh, A. M., "Eesays in Chcmiotry," (Editon: Bradley, J. N., Gillsrd, R. D., and Hudson, R.F.1, Aesdemie Prera, 1972, Volume 4, pp. 1-18, Price, C. C., J. CHEM. EDUC., 50.744 119731. Bunn,C.,Chem. BrLt.. 11,171 (19751. Rrnanrl R Arc Chem Rae
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