112.008 Design & Manufacturing IISpring 2004Polymer Processing I-What is polymer?-Polymer Science2.008 spring 2004 S. Kim 2Plastics $120 Billion shipments, 1999 US One of the greatest inventions of the millennium – Newsweek Music LPs, CDs No-sticking TEFLON Stre-e-e-tching SPANDEX ApplicationsName it2.008 spring 2004 S. Kim 3Plastic Intensive VehiclesCorvetteLotus2.008 spring 2004 S. Kim 4Automotive Plastics and Composites Use Exterior doors hoods  fenders  bumper covers (most cars have soft fascia) Interior instrument panels, door trim, seats, consoles Engine valve covers, intake manifolds, fluid containers, etc.2.008 spring 2004 S. Kim 5Recreational Plastics and Composites Use Snow Equipment skis, snow boards, snow mobiles, etc. Water Sports Equipment water skis, water crafts, snorkel equipment, fishing gear diving equipment and clothes Land Sports Equipment shoes, roller blades, skate boards, tennis, golf, etc.2.008 spring 2004 S. Kim 6Commercial Plastics Usage Packaging Wrapping, bags, bottles, foams, shrink wrap. Textiles Clothing, carpets, fabrics, diapers, netting for sports Furniture, Appliances, House wares Telephones and other communication equipment, computer housings and cabinets, luggage, seating, components for washers, dryers, etc. Musical instruments, CDs, VCRs, TVs, cases Construction Moldings, counter tops, sinks, flooring, cups, paints, etc. Tyvek22.008 spring 2004 S. Kimexcerpt from Prof. J. Greene, CSU7Medical Plastics and Composites Use Containers Bottles, bags Drug delivery IV bags, syringes tubing and tools for surgery Implants, artificial skins The use of plastic materials in the medical field, about 4 billion dollars in 2000 (US).2.008 spring 2004 S. Kim 8MaterialsSolid materialsmetalsceramicsPlasticsthermoplasticsthermosettselastomersPlastic: Greek,plastikos, means to form or mold2.008 spring 2004 S. Kim 9Plastics,Polymers, Macromolecules Poly (many) + mer (structural unit)-[C2H4]n- ,poly[ethylene] Metal: single atoms, metallic bond Ceramic: metallic oxides, ionic bond or dipole interactions, van der Waals bondsHHCCHHspaghettiHHCCHH2.008 spring 2004 S. Kim 102.008 spring 2004 S. Kim 11ThermoplasticsamorphouscrystallineTransparentTranslucentOpaque2.008 spring 2004 S. Kim 12Crystalline vs. amorphous Crystals, lamella structure Degree of crystallinity Translucent/opaque32.008 spring 2004 S. Kim 13Amorphous vs. Semi crystalline PolymersTgTg+60°CGlassy solidRubberyMeltVˆTgTmBrittleTough and flexibleMeltVˆ(a)(b)2.008 spring 2004 S. Kim 14Early Plastics•Phenolics (named Bakelite by Leo Bakeland)–Resin could be shaped and hardened with heat–Phenol and formaldehyde reaction after heat–Replacement for shellac, natural plastic (1907)•Nylon66- W. H. Carothers of DuPont (1920’s)•PVC- W. Semon of B.F. Goodrich (1929)2.008 spring 2004 S. Kim 15Polymers PE (Polyethylene)-Crystalline PVC (Polyvinyl chloride)-Amorphous PP (Polypropylene)-C PS (Polystyrene)-A PU (Polyurethane)-Thermoset PET (Polyethyleneterephthalate)-C PPO (Polyphenyleneoxide)_A PMMA (Polymethylmethacrylate) -A PEEK (Polyether-ether-ketone )-C Acetal, TEFLON -C2.008 spring 2004 S. Kimexcerpt from Prof. J. Greene, CSU16Major Plastic Materials (1995) LDPE ($0.38/lb) 6.4 M metric tons (1000 kg) HDPE ($0.29/lb) 5.3 M metric tons  PVC ($0.26/lb) 5.1 M metric tons  PP ($0.28/lb) 4.4 M metric tons  PS ($0.38/lb) 2.7 M metric tons  PU ($0.94/lb) 1.7 M metric tons  PET ($0.53/lb) 1.6 M metric tons  Phenolic ($0.75/lb) 1.5 M metric tonsTotal 28.6 M metric tons (82% of market) Nylon ($1.40/lb) 0.4 M metric tons  PTFE ($6.50/lb) <0.1 M metric tons  PEEK ($36.00/lb) <0.05 M metric tons 2.008 spring 2004 S. Kim 17Recycling of Plastics State and Federal Regulation Codes for plastics 1 PET 2 HDPE 3Vinyl/PVC 4LDPE 5PP 6PS 7Other12.008 spring 2004 S. Kim 18Polyethylene  Ethylene is produced by cracking higher hydrocarbons of natural gas or petroleum LDPE commercialized in 1939  Density of 0.910 - 0.925 g/cc Properties include good flex life, low warpage, and improved stress-crack resistance Disposable gloves, shrink packages, vacuum cleaner hoses, hose, bottles, shrink wrap, diaper film liners, and other health care products, films for ice, trash, garment, and product bags HDPE commercialized in 1957 Density of 0.941 - 0.959 g/cc MW from 200K to 500 K Densities are 0.941 or greater-Ultra HDPE Properties include improved toughness, chemical resistance, impact strength, and high abrasion resistance, high viscosities Trash bags, grocery bags, industrial pipe, gas tanks, and shipping containers, chairs, tables42.008 spring 2004 S. Kim 19Polypropylene PP invented in 1955 by Italian Scientist F.J. Natta. Advantages Low Cost, Excellent flexural strength, good impact strength Processable by all thermoplastic equipment Low coefficient of friction, excellent electrical insulation Good fatigue resistance, excellent moisture resistance Service Temperature to 160 C, very good chemical resistance Disadvantages High thermal expansion, UV degradation Poor weathering resistance Subject to attack by chlorinated solvents and aromatics Difficulty to bond or paint Oxidizes readily Flammable2.008 spring 2004 S. Kim 20PVC  Polyvinyls were invented in 1835 by French chemist V. Semon. PVC was patented in 1933 by BF Goodrich Company in a process that combined a plasticizer which makes it easily moldable and processed. Rigid-PVC Pipe for water drain, sewage Pipe for structural yard and garden structures Plasticizer-PVC or Vinyl Latex gloves Latex clothing Paints and Sealers Signs2.008 spring 2004 S. Kim 21PS (Polystyrene) PS Homopolymer (crystal): Clear and colorless with excellent optical properties and high stiffness. Brittle.  Impact polystyrene (IPS): Graft copolymer or blend with elastomers Properties are dependent upon the elastomer content, medium impact high impact and super-high impact Copolymers include SAN (poly styrene-acrylonitrile), SBS (butadiene), ABS. Expandable PS (EPS) is very popular for cups and insulation foam.  EPS is made with blowing agents, such as pentane and isopentane.  cell size and distribution2.008 spring 2004 S. Kim 22ABS ABS was