Chapter 9 - The World of Polymers and Plastics Flashcards Preview

Chemistry 1100 > Chapter 9 - The World of Polymers and Plastics > Flashcards

Flashcards in Chapter 9 - The World of Polymers and Plastics Deck (25):
1

Poly-

many

2

mer-

unit

3

polymer

many unit molecules (macromolecules)
-thousands of atoms, molar mass > 1 million
--> chains of chemical groups, can be linear/branched/radial

4

How many atoms are in a polymer?

MILLIONS!

5

What are examples of natural polymers?

silk, cotton, DNA, proteins

6

What are examples of synthetic polymers?

baklite, rayon, polyester, nylon

7

monomer

one unit, a molecule, building block of the polymer

8

What are plastics?

man-made polymers
-used in a wide variety of materials (ex. clothing, rubber)
-useful for foldability
-synthesized from available starting materials

9

Characteristics of Polymers

-molecular weight --> based on chain length
-chain arrangement --> organization/packing
-chain branding --> controls density
-monomer orientation (head vs. tail)
-interchain bonds (cross-linking)

10

What are the Big Six plastics?

1. Polyethylene Terephthalate (PET/PETE)
2. High Density Polyethylene (HDPE)
3. Polyvinyl Chloride (PVC)
4. Low Density Polyethylene (LDPE)
5. Polypropylene (PP)
6. Polystyrene (PS)

11

Polyethylene Terephthalate (PET/PETE)

Plastic #1
monomers: ethylene glycol + terephthalic acid
-transparent, strong, doesn't stretch, most $$$, no acid/atmospheric gases can pass through
-->ex. soft drink bottles, clothing

12

High Density Polyethylene (HDPE)

Plastic #2
monomer: ethylene
-similar to LDPE, denser, more opaque, mechanically tougher, more crystalline/rigid
--> ex. milk jug, stiff plastic bags

13

Polyvinyl Chloride (PVC)

Plastic #3
monomer: vinyl chloride
-rigid, thermoplastic, transparent, strong, no oils/organic materials can pass through
-->ex. plumbing pipe, garden hose

14

Low Density Polyethylene (LDPE)

Plastic #4
monomer: ethylene
-opaque, soft, flexible, no water vapor passes through, absorbs oils/softens
-->ex. plastic bags, bubble wrap

15

Polypropylene (PP)

Plastic #5
monomer: propylene
-opaque, high boiling point, strong, lowest density, no liquids/gases can pass through, smooth surface
-->ex. battery cases, bottle caps

16

Polystyrene (PS)

Plastic #6
monomer: styrene
-glassy, sparkling clarity, rigid, soluble in many organic materials
-beads + organic solvent = foam solid w/gas bubbles (foaming agent: CFCs, Pentane, CO2)
-->ex. styrofoam, drinking glasses

17

Plastic Functional Groups

The functional groups of the monomer determine the polymer’s chemical properties
--> H, CH3, C6H5, COOH

18

Common properties of plastics

Thermoplastics: flexible, melt & shape

regions:
-Crystalline: tight packing, regular shape --> makes tougher plastics, high density = high durability
-Amorphous regions: random orientation --> more flexible

19

What is polymerization?

a process of reacting monomer molecules together in a chemical reaction to form polymer chains or three-dimensional networks

20

Making PE from E

-cheapest, simplest synthetic polymer
-two forms: HDPE, LDPE

21

HDPE vs. LDPE

LDPE - more branching = higher density (CHECK BOOK)

22

Addition Polymers

all atoms in monomer are in polymer
-HDPE, LDPE, PP, PVC, PS
-no side products
-molecular weight: 10,000-100,000 carbon atoms

23

What are the intermolecular forces?

hydrogen bonding (strongest)
dispersion forces: on molecule, not permanent = weaker, negative charges attracted to positive charges (LOOK IN BOOK)

24

What are the orientation effects?

head to tail --> head to tail
heat to head --> tail to tail
random

--> rigidity increases up the list

25

Condensation of Polymers

some atoms (ex. H2O, HCl) from monomer are removed in polymerization (ex. PETE)