Chemistry- Polymers

Question 1

definition of polymer

Answer 1

“many units”

Question 2

what is a polymer?

Answer 2

A very long molecule made up of many units

Question 3

What makes up a polymer?

Answer 3

monomer

Question 4

draw down the formula to present polymers:

Question 5

what do the properties of polymers depend on?

Answer 5

1- Where the monomers are made from
2- condition polymer is made in

Question 6

What are the two types of polymers?

Answer 6

Low density poly (ethene)
High density poly (ethene)

Question 7

The properties of a Low Density Poly (ethene)

Answer 7

• flexible
• can make film
• unreactive

Question 8

The properties of High Density Poly (ethene)

Answer 8

• flexible
• resistant to chemicals
• strong

Question 9

What are the two types of plastics?

Answer 9

• Thermosoftening
• Thermosetting

Question 10

Draw Thermosoftening plastics structure:

Question 11

Draw Thermosetting plastic structure:

Question 12

Do Thermosoftening plastics melt when heated?

Answer 12

Yes, they do melt remember this as they are “soft” they can melt easily

Question 13

Do thermosetting plastics melt?

Answer 13

NO, think of this as the setting of your phone and how you cant remove it from your phone

Question 14

What is a composite material?

Answer 14

two or more materials with different properties

Question 15

What are most Composite Materials made of?

Answer 15

• Reinforcement (main material)
• Matrix (hold the main material together)

Question 16

Examples of Composite materials?

Answer 16

• Chipboard: Made of Wood chips held by glue
• Reinforced concrete:made of steel roads and surrounded by concrete

Question 17

Polymers are Giant Covalent networks true or false?

Answer 17

False.

Question 18

why is poly (ethene) a solid at room temperature but carbon dioxide is a gas?

Answer 18

its a solid because its long chains are eld by strong forces. carbon dioxide is a gas because its small molecules have weak forces and spread out easily

Question 19

Name the forces that act between polymer molecules. and are they weak or strong

Answer 19

intermolecular forces that are strong so they are solids at room temp

Question 20

What determines the properties of polymers?

Answer 20

The structure of the polymer and the type of bonding between monomers determine its properties.

Question 21

What are thermosetting polymers?

Answer 21

Thermosetting polymers harden when heated and cannot be reshaped.

Question 22

What are thermosoftening polymers?

Answer 22

Thermosoftening polymers soften when heated and can be reshaped.

Question 23

What do we mean by “matrix” in a composite material?

Answer 23

The matrix is the material that holds the reinforcement (like fibers) in place in a composite.