35.3 A2 Level

Degradable polymers

Cambridge A-Level Chemistry (9701)  · Unit 35: Polymerisation (A Level)  · 7 flashcards

Degradable polymers is topic 35.3 in the Cambridge A-Level Chemistry (9701) syllabus , positioned in Unit 35 — Polymerisation (A Level) , alongside Condensation polymerisation and Predicting the type of polymerisation.  In one line: Ultraviolet (UV) radiation can break down certain polymers. The UV photons provide sufficient energy to break chemical bonds in the polymer chain, leading to degradation.

Marked as A2 Level: examined at A Level in Paper 4 (A Level Structured Questions) and Paper 5 (Planning, Analysis and Evaluation). It is not tested on the AS-only papers (Papers 1, 2 and 3).

The deck below contains 7 flashcards — 3 definitions and 4 key concepts — covering the precise wording mark schemes reward.  Use the 3 definition cards to lock down command-word answers (define, state), then move on to the concept and calculation cards to handle explain, describe, calculate and compare questions.

Key definition

What type of electromagnetic radiation can degrade some polymers

Ultraviolet (UV) radiation can break down certain polymers. The UV photons provide sufficient energy to break chemical bonds in the polymer chain, leading to degradation.

Example: Degradation of polymers in sunlight.

What the Cambridge 9701 syllabus says

Official 2025-2027 spec · A2 Level

These are the exact learning outcomes Cambridge sets for this topic. The candidate is expected to be able to do each of these on the relevant paper.

  1. recognise that poly(alkenes) are chemically inert and can therefore be difficult to biodegrade
  2. recognise that some polymers can be degraded by the action of light
  3. recognise that polyesters and polyamides are biodegradable by acidic and alkaline hydrolysis

Cambridge syllabus keywords to use in your answers

These are the official Cambridge 9701 terms tagged to this section. Mark schemes credit responses that use the exact term — weave them into your answers verbatim rather than paraphrasing.

biodegradable alkaline hydrolysis poly(alkenes)

Tips to avoid common mistakes in Degradable polymers

Key Concept Flip

Why are poly(alkenes) like poly(ethene) difficult to biodegrade?

Answer Flip

Poly(alkenes) possess strong, non-polar carbon-carbon bonds and are chemically inert. This inherent stability makes them resistant to breakdown by microorganisms in the environment, hindering biodegradation.

Example: Poly(ethene) in landfill persists for a very long time.
Definition Flip

What type of electromagnetic radiation can degrade some polymers?

Answer Flip

Ultraviolet (UV) radiation can break down certain polymers. The UV photons provide sufficient energy to break chemical bonds in the polymer chain, leading to degradation.

Example: Degradation of polymers in sunlight.
Key Concept Flip

What is the key difference in bonding that makes polyesters and polyamides biodegradable compared to poly(alkenes)?

Answer Flip

Polyesters and polyamides contain polar ester (-COO-) and amide (-CONH-) linkages, respectively, which are susceptible to hydrolysis. Poly(alkenes) contain non-polar C-C bonds which are much more stable and resist hydrolysis.

Definition Flip

Name two conditions that can hydrolyse polyesters and polyamides.

Answer Flip

Acidic and alkaline conditions. The ester and amide bonds in these polymers undergo hydrolysis when exposed to acids or bases, breaking down the polymer chains.

Key Concept Flip

Explain how the structure of a degradable polymer affects its rate of degradation.

Answer Flip

The presence of hydrolysable bonds (like ester or amide links) directly increases degradability. The accessibility of these bonds to water or microorganisms also plays a key role.

Example: More ester links mean faster degradation, and greater surface area also increases degradation speed.
Definition Flip

Define 'biodegradable'.

Answer Flip

A substance that can be broken down into simpler substances (e.g. CO2, water, biomass) by the action of living organisms (bacteria, fungi) or their enzymes. Biodegradable polymers can be broken down naturally.

Key Concept Flip

Describe alkaline hydrolysis of a polyester or polyamide.

Answer Flip

Alkaline hydrolysis involves the reaction of the ester or amide bonds with hydroxide ions (OH⁻) from a base (e.g. NaOH). This process breaks the polymer chain at the ester/amide linkages, forming smaller molecules.

More Chemistry flashcards

Browse every 9701 flashcard topic by syllabus area.

All Chemistry Flashcards
35.2 Predicting the type of polymerisation 36.1 Organic synthesis

More topics in Unit 35 — Polymerisation (A Level)

Degradable polymers sits alongside these A-Level Chemistry decks in the same syllabus unit. Each uses the same spaced-repetition system, so progress in one informs the next.

Key terms covered in this Degradable polymers deck

Every term below is defined in the flashcards above. Use the list as a quick recall test before your exam — if you can't define one of these in your own words, flip back to that card.

What type of electromagnetic radiation can degrade some polymers
Name two conditions that can hydrolyse polyesters and polyamides
'biodegradable'

How to study this Degradable polymers deck

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