Questions on Environmental impact - plastics

1. The structures of the repeating units of three polymers, polyethylene terephthalate (PETE), polyvinyl chloride (PVC) and polystyrene are shown below.

A substance sent for recycling is known to be made of one of these three polymers. The substance gives the following infrared spectrum.

Explain how the infrared spectrum can be used to identify the polymer and its Resin Identification Code (see Sections 26 and 30 of the data booklet).

2. (a) Using the structure of the repeating unit shown above state the equation for the complete combustion of polystyrene at a very high temperature.

(b) Explain why the combustion of polystyrene at lower temperatures (e.g. in a house fire) can produce products that are hazardous to health.

3. Explain why high molecular mass phthalate esters (e.g. bis(2-ethylhexyl)phthalate, BEHP) have replaced low molecular mass phthalate esters (e.g. dibutylphthalate, DBP) as plasticizers.

4. An analysis of the silt at the bottom of an estuary in New Jersey showed the presence of the three persistent organic pollutants (POPs) whose structures are shown below:

(a) Identify the class of organic compounds to which these three pollutant belong.

(b) State one possible source of these three pollutants

(c) State why they are considered to be a serious hazard to human health.

Environmental impact - plastics questions