Polymer Facts

By: Scarlett Lonsky, Troy Tratt, and Catherine Kopp

History

Applications

• John W. Hyatt won a contest using Celluloid (trees, grains) to replace ivory in 1868

Innovative Traditional

• Natural Polymers: Silk, Wool, Proteins Chemically Combined in 1800s: Rubber, Gun Cotton

• In 1909: First semi-synthetic (came from multiple substances) polymers, made by Bakelite

• water bottles
• clothing
• plastic bags
• utensils

• skin healer
• plastic lumber
• tendon builder
• water collection

• In 1911: First synthetic fiber (made through a chemical process), produced by Rayon

• After World War Two, polymers became more important due to the loss of natural resources

latex, wool, silk nylon, acrylic, neoprene

• The reasons people use certain plastics: water proof; durable; they aren't conductors of heat; flexible; strong

• Examples of Recyclable Plastics: water bottles, bags

Polymer Facts

• polymers are usually synthetic--man-made

Raw Materials

Cites

Original Form

able to create things for a specific purpose

Examples

Where they come from:

• environment--forests and animals

• tar
• shellac
• horns
• tortoise shells
• oil
• natural gas
• certain tree saps
• celluloid--trees and grains

• they conserve natural resources
• polymers are usually created from natural things--they are then processed with heat and pressure
• People use polymers because they are durable, waterproof, and they don't conduct heat

• http://www.plasticpackagingfacts.org/Plastics-101
• http://www.styron.com/image/plastics-life-cycle-2.jpg
• http://www.thesaurus.com/browse/resistance
• plastics.americanchemistry.com
• plymerexpert.fr
• ensinger-online.com
• http://plastics.americanchemistry.com/Education-Resources/Plastics-101/The-Basics-Polymer-Definition-and-Properties.html
• http://www.cmu.edu/gelfand/k12-teachers/polymers/natural-synthetic-polymers/index.html
• http://dictionary.reference.com/browse/synthetic?s=t
• http://www.chemheritage.org/research/policy-center/oral-history-program/projects/rubber-matters/feature-polymers-a-brief-history.aspx
• http://sciencelearn.org.nz/Contexts/Enviro-imprints/Looking-Closer/Measuring-biodegradability
• Cope's Plastics Book, By: Dwight Cope, 272 pages, The Goodheart-Willcox Co.
• Engineering Materials Technology, By: James A. Jacobs and Thomas F. Kilduff, 633 pages, Premtice Hall Career and Technology

After Processing

Examples

• hair pieces
• jewelry
• water bottles
• lining to mechanical pencils
• clothes
• garbage bags
• containers

RECYCLED/REUSE:

• water bottles are turned in for money
• you wear clothes many times before they wear out
• mold certain plastics into a different use
• use sturdier bags at the grocery store instead of new plastic bags every time
• recycled plastics: Thermoplastics (molecular chains aren't cross-linked)

Electrical Properties

Mechanical Properties

High density and molecular weight

Leads to, "increase in tensile strength, hardness, creep resistance, and fluxural strength."

• plastics are good insulators
• resist the heat of silicons and fluorocarbons well
• arc resistant ("ability of a material to withstand the arcing effect of an electrical current.")

Leads to decrease in "impact resistance and percentage of elongation."

The living hinge--polypropylene and polyethylene:

• bends like a hinge
• is connected throughout (no additional materials)

When carbonized, either:

• become a conductor (flames create thin tracks between electrodes)

• become an incandescent (glowing hot) conductor

Material Classification

Acoustical Properties

Comparative Characteristics

Thermal Properties

• has sound properties--polymers are used for dampening sound
• need to put holes in it and shape it well for it to allow sound to travel (used in auditoriums)

Common plastics:

8 Properties of Polymers:

• loose strength at low temperatures
• (low-no stress) can not take temperatures above 150 Degrees Celsius

Thermoplastics:

• molecular chains are not linked together

• have plastic elastic ability and are thermo-formable(being able to be welded)

hard rubbery, supper cooled liquid liquid

• not good conductors of heat

containers, outlet liners

• volume decreases when cooling as a result of the "thermal mixing of the atoms and molecular chains..." slowing down

Thermoset Plastics:

Electrical

Acoustical

Environmental

Physical

Mechanical

Thermal

Chemical

Optical

• molecular chains are close together and are "cross linked"

Environmental Properties

• polymers are usually made from petroleum
• for the most part, plastics are recycled versions of natural gas, crude oil, or coal (They can also come from celluloid--trees and grains)
• many medical devices rely on polymers
• Polymers decompose slowly--plastic bags take, "500 years to forever," to biodegrade (scientists use respirometry tests to figure this out)
• plastics can be processed:

Chemical Properties

• they can't be shaped after hardened
• they can not be melted
• they have good chemical protection

• They don't corrode like metals
• But, may experience a chemical reaction or deterioration

• as temperature increases, the chemical tolerance decreases as a result

• mimic other materials (cotton, silk, wool fibers
• injection molding (car parts)
• create unnatural things--clear sheets, flexible films

measured by the amount of weight gained (Chemical combines with the plastic)

results in discoloration of the material, fine cracks throughout the substance, and swelling loss of flexibility and impact strength

Physical Properties

• usually light weight (plastic water bottles are lighter than metal water bottles)
• strong but some are also flexible
• there is a large range in material use--mechanical pencil lining to Kevlar (bullet-proof vests)
• some retain a certain shape while others are willing to change their shape
• polymers come in many different colors

Optical Properties

Polymers

• high crystalline opacity developes
• plastics have an amorphous structure--transparent
• can bend light (serves as light pipes)
• "certain plastics (acrylics, polyester, cellulose, and polystyrene) show colorful stress concentrations when viewed with a polarized-light filter."

• many different shapes

many different colors

3D Model: World of Plastics

Steps:

• found a circular shape object
• paper-machaed it with glue and graphing paper
• drew out the continents according to the Library's globe size
• painted it blue
• covered each continent with some sort of polymer
• touched it up

Importance:

• shows commonly used polymers that we may not recognize as such
• demonstrates that people all over the world use them
• represents the world-wide importance of plastics

RECYCLE SYMBOLS: