QUIZ 3

Question 1

Plastics, commonly used in commercial applications, are derived from

Answer 1

polymers or prepolymers.

Question 2

while plastics are a type of polymer, ________polymers are plastics

Answer 2

not all

Question 3

pure material which is usually the umbrella term for materials which have long chain-like molecules.

Answer 3

Polymer

Question 4

made up of large molecules consisting of structural units called monomers, which
gives plastics their distinctive properties and versatility

Answer 4

polymers

Question 5

key mechanism behind
plastics production

Answer 5

polymerization

Question 6

There are different types of polymerization but in plastics, ____________________
polymerizations are usually applied.

Answer 6

addition and condensation

Question 7

the monomer units containing double or triple bonds or unsaturated
molecules, are added successively to form a linear polymer chain.

Answer 7

addition polymerization

Question 8

An example of a plastic that conforms to addition polymerization is

Answer 8

polyethylene

Question 9

involves formation of polymers through the elimination
of small molecules such as water, as monomers react

Answer 9

condensation polymerization

Question 10

An example
of condensation polymerization is the synthesis of

Answer 10

polyester Dacron and polyamide Nylon 66.

Question 11

e backbone of modern plastics

Answer 11

polymers

Question 12

The molecular weight and chain length of polymers directly impacts the

Answer 12

strength and durability of plastics

Question 13

Shorter chain length often translates to __________ polymer,

Answer 13

weaker

Question 14

the presence of side chains attached to
the main polymer chain

Answer 14

branching

Question 15

Branching influences

Answer 15

flexibility and elasticity

Question 16

______ polymers are rarely used on their own

Answer 16

pure

Question 17

usually incorporated to polymers to further
enhance the properties of the resulting plastics, allowing for customization to meet specific requirements.

Answer 17

Additives

Question 18

Some of the common additives used in the plastic industry are

Answer 18

Antioxidants
Antistatic agents
Blowing agents
Fillers
Flame retardants
Heat stabilizers
Pigments
Plasticizers
UV Stabilizers

Question 19

function as a protective agent for polymers during thermal processing to
avoid product deterioration in short and long-term use at elevated temperatures.

Answer 19

heat stabilizers

Question 20

utilized to impart colors to plastics.

Answer 20

Pigments and dyes

Question 21

These are added to plastics to aid flow and processing.

Answer 21

plasticizers

Question 22

They are low molecular weight
materials that alter the properties and forming characteristics of the plastic

Answer 22

plasticizers

Question 23

These are used in plastics to inhibit both oxidative degradation and thermal oxidation.

Answer 23

antioxidants

Question 24

makes it possible for plastic
surfaces to attract moisture from air which improves its surface conductivity and reduces thertm
chances of a spark or discharge.

Answer 24

antistatic agents

Question 25

These are added to plastics to make foam or cellular structures in the final product.

Answer 25

blowing agents

Question 26

are solid particles that are incorporated into plastics to enhance properties and reduce costs

Answer 26

Fillers (inorganic)

Question 27

enable large volumes of plastic using a small amount of polymer resin

Answer 27

extender

Question 28

frequently used as extenders.

Answer 28

Low-cost solids like calcium carbonate, silica, and clay

Question 29

Reduce the likelihood that combustion will occur or spread.

Answer 29

Flame retardants

Question 30

Examples of flame retardants

Answer 30

chlorine, nitrogen, bromine, phosphorus, or metallic salt

Question 31

long chain-like molecules are kept together by weak van der Waals forces

Answer 31

thermoplastics

Question 32

typically measured using the molecular weight and molecular weight distribution of the polymer

Answer 32

chain lengths

Question 33

thermoplastic materials with the same chemical formula to exist in distinct molecular configurations, resulting in extremely diverse characteristics

Answer 33

isomerism

Question 34

the most commonly used thermoplastic

Answer 34

polyethylene

Question 35

When it takes the form of a mostly linear chain, the chains can be packed closely together, and the material is known as _____________

Answer 35

HDPE

Question 36

Other common commercial thermoplastics

Answer 36

(PVC), polystyrene, nylon, cellulose acetate, polycarbonate, polyethylene terephthalate (PET), polymethyl methacrylate, polylactic acid (PLA), and polypropylene

Question 37

A key distinction among thermoplastic materials

Answer 37

amorphous or crystalline

Question 38

Some polymers, such as polyethylene and nylon, can acquire high levels of crystallinity, however they are perhaps better classified as

Answer 38

partially crystalline or semi-crystalline

Question 39

Other plastics, including acrylic and polystyrene, are invariably

Answer 39

amorphous

Question 40

the mechanical qualities of the molding are highly dependent on whether or not the plastic is

Answer 40

crystalline

Question 41

In general, plastics have a higher density when

Answer 41

crystallized

Question 42

Properties of amorphous polymers

Answer 42

Broad softening range Usually transparent Low shrinkage Low chemical resistance Poor fatigue and wear resistance

Question 43

Properties of crystalline polymers

Answer 43

Sharp melting point Usually opaque High shrinkage High chemical resistance Good fatigue and wear resistance

Question 44

The most common type of plastic is called

Answer 44

commodity plastics

Question 45

utilized in huge quantities in a variety of applications

Answer 45

commodity plastics

Question 46

Commodity plastics are mostly used in

Answer 46

packaging, toys, clothes, transportation, and domestic products