I just want to say one word to you... just one word... Plastics -the graduate
Quiz! 1. What is your name? 2. Which are polymers: wood, skin, Jell-O, DNA 3. Where does almost all plastic come from? 4. Which requires more energy to produce: Paper or Plastic bags?
What are Polymers? greek for many parts long chains of repeating molecules (monomers) natural polymers: proteins, starch, cellulose synthetic polymers...
What is Plastic? synthetically polymerized material... typically from hydrocarbons from crude 6-10 percent of U.S. oil consumption - approximately 2 million barrels a day * green plastic oil can * lawrence livermore, 2004; metabolix 2007
Thermoplastics vs Thermosets THERMO (heat) PLASTIC (deform) THERMO (heat) SET (permanent)
Thermosets melamine Permanent, Chemical Reaction! Polymer Chains are cross-linked. Usually two-part exothermic, or heat treated phenolics Used in for high temp, high tolerance, or joining not recyclable. vulcanized rubber
Thermoplastics most common with toys easy to (re)shape with different processes. chains relax mostly recyclable 9 common thermoplastics Acrylonitrile-Butadiene-Styrene (ABS) PolyVinyl Chloride (PVC) PolyPropylene (PP) PolyEthylene (PE) PolyStyrene (PS) PolyMethylMethArylate (Acrylic) PolyCarbonate (PC) PolyEsters (PET, PETE) PolyAmide (Nylon, PA)
Plastic Shaping Processes Compression Molding (thermosets) Injection Molding Thermoforming Blow Molding Rotational Molding
Compression Molding for complex parts with various thickness thermosets
Injection Molding for thin constant thickness parts gate, parting lines, ejector pins mass production, molds are expensive
Thermoforming glass transition, relaxing the chains for thin sheets, simple one sided forms
Blow Molding for open thin walled hollow parts milk jugs, most bottles
Rotational Molding for simple closed hollow shapes good for inexpensive large parts
Crazing network of small voids or cracks strain whitening
Thermoplastics Acrylonitrile-Butadiene-Styrene (ABS) PolyVinyl Chloride (PVC) popular toy plastics PolyPropylene (PP) PolyEthylene (PE) ABS PVC PP PE PolyStyrene (PS) popular clear plastics PolyMethylMethArylate (Acrylic) PolyCarbonate (PC) PolyEsters (PET, PETE) PS PMMA PC PET PolyAmide (Nylon, PA)
Thermoplastics Game popular toy plastics ABS PVC PP PE popular clear plastics Physical Properties: feel, look, smell density, stiffness, opacity, surface finish Manufacturing Properties: What are the processes used with this plastic? thickness, detail, size? PS PMMA PC PET Design Considerations: Which types of products use this plastic? What is the cost of these products?
ABS Hard with high impact resistance Takes color well with excellent surface finish Consumer product cases Most expensive out of PVC, PP, PE
PolyVinylChloride (PVC) cheap, heavy, rigid, durable but not tough without plasticizers vinyl designer toys - not constant thickness outdoor/water products characteristic smell environment concerns
PolyEthylene (PE) most common plastic HDPE, LDPE cheap, very flexible, easy to (blow) mold, less dense than water waxy feel, milky, crazes highly resistant to food, water, salt, chemicals
PolyPropylene (PP) VERY similar to PE but... a bit more rigid doesn t fatigue: hinges, snaps shinier surface with better color acceptance harder to scratch and craze
Compare ABS, PVC, PP, PE ABS PVC PP PE Hard Colorful Strong Durable/Gummy Flexible* Unique shapes No Fatigue Tough Shiny Surface Flexible Food/Chemical Safe Waxy Stiff Flexible High $ Low $ Nicest Finish Worst Finish
Polystyrene (PS) clear, hard, cheap, brittle, tinny sound typically foamed to Styrofoam good for lightweight insulation if it cracks or crazes easily
PolyMethylMethAcrylate PMMA, Acrylic, Plexiglass transparent like glass, hard, brittle, but stronger than PS great for laser cutting can weld with superglue PMMA particles suspended in water
Polycarbonate (PC) the engineering plastic expensive, extremely tough and rigid... and clear
Polyesters (PET, PETE) cheap, transparent, easy to blow mold food products, barrier to moisture tough, able to withstand high pressures easy to recycle, require less energy than glass bottles
Compare PS, PMMA, PC, PET PS Acrylic PC PET tin sound brittle light weight glass like less brittle tough hard water proof tough blow mold Brittle Strong Low $ High $
Team Quiz 1. What is your team name? 2. Identify the plastic that makes up the majority of each toy piece. 3. What makes you think it is that plastic? / Why was that plastic used?
Plastic Recycling not everything gets recycled (even if it s recyclable) collecting air, sorting, shredding, cleaning processing 80% is sent to landfill 8% is incinerated 7% is recycled * * 2001 Environment Agency report
Energy In Plastic Energy Density of Crude Oil ~ 40MJ/kg 5 lbs of plastic Gallon of Gasoline ~
Paper vs. Plastic 2 plastic bags use 13% less energy to make than one paper bag and produce 72% less pollutants than one paper bag but do not degrade and come from a non renewable resource * institute for lifecycle environmental assessment
Logistics ONLY 3 Weeks left! PLAYsentations are Wednesday May 7th, 7pm, Coffman Theatre Rehearsal is Monday May 6th, 4-10 pm, Coffman Theatre (30 min slots) Presentation Consultations: April 28 and 30 during lecture (Kate Maple and Chris Schlichting) Marketing Consultations: April 23 during lecture (Kate Reiling, Katie Konrath, ++) Keynote workshop? PLAYsentations guidelines next week
Questions