180 likes | 2.44k Views
Polyethylene naphthalate (PEN). Moni Muraki Heidi Pecoraro CHEM 231 November 28, 2005. Esterification Reaction. ethylene glycerol. +. H 2 O. naphthalene dicarboxylic acid. Ethylenenaphthalene Monomer. naphthalene group. ethylene group. Condensation Polymerization.
E N D
Polyethylene naphthalate(PEN) Moni MurakiHeidi PecoraroCHEM 231November 28, 2005
Esterification Reaction ethylene glycerol + H2O naphthalene dicarboxylic acid
Ethylenenaphthalene Monomer naphthalene group ethylene group
Condensation Polymerization • Same reaction that forms monomer • Step-growth polymerization – combines two molecules and removes a small molecule • Polyesters are formed by this mechanism • Heat (∆) catalyzes the reaction • Not chain-growth polymerization – instead any two reactive molecules can combine
PEN Polymerization H2O H2O
PEN: Uses • Can be processed into films, fibers, and containers • Film: media tapes • Fibers: electrical insulation, cords/cables, tire cord, narrow- and broad-woven fabrics, synthetic molecular membranes • Containers: bottles, jars, tableware
PEN: A Brief History • In the UK, ICI Alkali Division laboratories produced polyethylene in 1935 • Polyethylene has thermoplastic properties that were vital to the development of radar • 1953 – DuPont first commercial production of PEN fiber for carpets • Currently >2000 patents for PEN products
PEN: Health Risks? • None found, however: • Exposure to high amounts of naphthalene can damage or destroy RBCs and has been shown to cause cancer in rats • Classified as possibly carcinogenic in humans • Ethylene glycol is a suspected toxin in the following systems: • Cardiovascular, developmental, GI, liver, kidney, neurological, reproductive, respiratory, and skin/sense organs
PEN: Health Risks? • Polyethylene hazards: skin and eye irritation • Polyethylene terephthalate (PET) – a close relative of PEN: phthalates (which can act as endocrine disruptors) leach into water or food if the container is heated
PEN: Properties • High temperature resistance • High glass transition temp (unlike PET) • High UV resistance • Resistant to hydrolysis in alkaline or very hot aqueous conditions • Rigid, transparent, colorless • Thus, slow degradation
PEN: Recycling • Commercial recycling firms • Bottles and jars – recyclable and reusable • Containers can be recycled • PEN can be sterilized at high temperatures
References • E.S. Stevens. 2001. Green Plastics: An introduction to the new science of biodegradable plastics. <http://www.pupress.prinston.edu/chapters/s7228.html>, accessed November 22, 2005. • The History of Plastics. 2005. <http://www.bpf.co.uk/bpfindustry/History of Plastics.cfm>, accessed November 25, 2005 • Color your carpet. 2005. History of Dyes. <http://www.coloryourcarpet.com/History/ DyeHistory.html>, accessed November 25, 2005 • British Petroleum. 2001. Elements: naphthalates from bp-expanding the use of polyesters. 1(1):Summer 2001. • H. Meimberg, S. Thalhammer, A. Brachmann, B. Muller, L.A. Eichacker, W.M. Heckl, G. Heubl. 2003. Selection of chloroplasts by laser microbeam microdissection for single-chloroplast PCR. Biotechniques 34(6):1238-43. • M.S.M. Alger (ed). 1989. Polymer science dictionary. Elsevier Science Publishers LTD. 346p. • P.Y. Bruice. 2004. Organic Chemistry. 4th ed. Pearson Education, Inc. 1148p. • T. Furatani. 2005. Organic Chemistry Lecture, NSCC. November 23, 2005. • Wikipedia. 2005. Naphthalene. <http://en.wikipedia.org/wiki/Naphthalene>, accessed November 18, 2005. • Scorecard: the pollution information site. 2005. Ethylene glycol. <http://www. scorecard.org/chemical-profiles/summary>, accessed November 18, 2005. • M.L. Berins. 1991. Spi Plastics Engineering Handbook of the Society of the Plastics Industry, Inc., 5th ed. Van Nostrand Reinhold Publisher. 67p. • Polymer Science Learning Center. 2005. Polyester. <http://www.pslc.ws/ mactest/pet.htm>, accessed November 25, 2005. • Sirex. 2005. 3R-Foam, Range of Applications. <http://www.recycledfoam. com/applications.htm>, accessed November 25, 2005. • Landscape Structures. 2005. Recycled Polyethylene Bench. <http://www.playlsi.com /Products/Accessories/SiteAmenities/Recycled+PolytheyleneBench/RecycledPoly Bench.htm>, accessed November 25, 2005. • Plastics resource.com. 2005. Information on plastics and the environment. <http://www.plasticsresource.com>, accessed November 2, 2005.