Module 4: Environmental concerns Flashcards

1
Q

Recycling Polymers:

A

Discarded polymers organised into types - polymers chopped into flakes - washed - dried - melted - cut into pellets and reused

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

PVC Recycling:

A

-Grinding PVC to be reused
or
-Using solvents to dissolve the polymer - high-grade PVC then recovered by precipitation and solvent reused.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Using waste polymers as fuel:

A

Some polymers are difficult to recycle but have a high stored energy value - incinerated to produce heat - generate steam - turn a turbine.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Feedstock Recycling:

A

Chemical and thermal processes that reclaim monomers, gases, or oil from waste polymers.
Can be used for mixed and unsorted polymers.
Products can be used as raw materials to produce new polymers.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Biodegradable polymers:

A

They are broken-down by microorganisms into water, CO2, and biological compounds. They are usually made from starch, cellulose or they contain additives that alter their structure to allow for them to be digested by microorganisms.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Photodegradable Polymers:

A

Photodegradeable oil-based polymers have their bonds weakened by sunlight - start degrading.
Light absorbing additives can also be used.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Why is recycling PVC hazardous:

A

It has a high chlorine content - landfill is not sustainable - when burnt releases corrosive hydrogen chloride gas and other pollutants.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Bioplastics:

A

Bioplastics are produced from plant starch, cellulose, plant oils, and proteins. They offer a renewable and sustainable alternative to oil-based products)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Compostable polymers:

A

They degrade leaving behind no visible or toxic substances. Based on lactic acid.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly