Question 1
Does addition polymerisation produce water? Explain.
Need a hint for Question 1?
Keep both former C=C carbons in the backbone and preserve their side groups.
Check Question 1
No. All atoms of the alkene monomers enter the polymer.
STUDENT SPACE · TOPIC 1
Addition polymers
Deduce addition-polymer repeat units and recover their monomers.
The essentials
- A polymer is a large molecule built from many smaller monomer molecules. Plastics are made from polymers.
- Ethene CH₂=CH₂ forms [–CH₂–CH₂–]ₙ. The repeat unit has two carbon atoms linked by a single bond.
- Propene CH₂=CHCH₃ forms [–CH₂–CH(CH₃)–]ₙ. The CH₃ group remains a side group.
Key vocabulary
| English | Chinese |
|---|---|
| monomer | 单体 |
| polymer | 聚合物 |
| repeat unit | 重复单元 |
Quick practice
Try each question before opening its hint or answer. Use paper for calculations and diagrams.
Question 2
Draw three joined repeat units of polyethene.
Need a hint for Question 2?
Each ethene contributes two backbone carbons.
Check Question 2
–CH₂–CH₂–CH₂–CH₂–CH₂–CH₂–, with continuing bonds at both ends.
Question 3
Deduce the monomer from [–CF₂–CF₂–]ₙ.
Need a hint for Question 3?
Restore a double bond between the two backbone carbons.
Check Question 3
CF₂=CF₂, tetrafluoroethene.
Use Lesson 1 in your worksheet for written practice. Your teacher will discuss those answers in class.