A Chemistry WebQuest
PVC is short for poly(vinyl chloride). This polymer is made by polymerizing the monomer vinyl chloride.
PVC is a very strong and very rigid plastic, and it's a really useful one, too. People use it to make pipes, the kind used for plumbing in most newer houses. PVC is also used to make the "vinyl" siding on the outside of houses.
PVC is also flame-resistant because it contains chlorine. Compounds that contain chlorine often are. Because of this, PVC is useful for making fixtures for the interiors of airplanes, where a fire could be especially dangerous.
PVC also can be made into a soft and flexible plastic by mixing it with small-molecule compounds called plasticizers. The "new car" smell that motorists love so much comes in part from plasticizers evaporating from PVC in the seats and dashboards. Plasticized PVC can be used for a lot of things. It's waterproof, so it can make things like tarps and raincoats. It's also good for making clear flexible tubing.
But there is a problem: Those plasticizers that make PVC soft and flexible can be toxic and carcinogenic. The PVC itself isn't toxic or carcinogenic, but the plasticizers can cause health problems. As if that weren't enough, the monomer used to make PVC, vinyl chloride, is carcinogenic and can be harmful to people who work in the factories where PVC is made.
Your Task
Coming up with a solution won't be easy. Using PVC has risks, and some people would like to
ban it. This may seem like a good idea, but alternatives to PVC aren't always easy to find. In
this activity, you and a partner will set out on a quest to find solutions to the PVC dilemma.
The Process
As a team of two, one of you will research PVC and what its uses and benefits are. The other
team member will research the risks of using PVC. Each of you will prepare a 1-2 page report of
your findings.
Once you have written your reports, you are to prepare another written report, this time on your
ideas for possible solutions. Please try to avoid simplistic solutions such as "stop using
PVC." That only works if you have a good replacement for PVC in every possible use. Rather,
your written report should answer the following questions:
Resources
To give you a head start, some online resources that you may find useful have been listed below.
For the uses and benefits of PVC:
PVC-Toys.com — industry-based advocacy group.
Chlorophiles — an organization of workers in PVC-related industries, based in Belgium. The site contains an
ample list of other PVC and
chlorine-related sites.
For the risks of PVC:
Europe to ban PVC toys
— report from BBC News.
New Concerns about
Phthalates — explores the risks posed by plasticized PVC, from Science News.
Our Stolen Future — site on the risks of
hormone-distrupting compounds, including phthalates used to plasticize PVC.
For additional information on PVC, plastics, and polymers:
Simple treatment
makes PVC safer — report from BBC News.
FDA Public Health Notification:
PVC Devices Containing the Plasticizer DEHP — from the U.S. Food and Drug Administration.
Conclusion
After you and your partner have completed your final report, there will be a class discussion of
the issues at hand and the solutions proposed by all the teams in the class.
Vinyl: One Material, Infinite Uses — from the Vinyl Institute, the Vinyl
Council of Canada, and the European Council of Vinyl Manufacturers.
It's Perfectly
Clear: The Case Against PVC Packaging — from the Massachusetts Public Interest Research
Group.
The Macrogalleria — a
comprehensive resource of polymer information from the Polymer Science Learning Center at the
University of Southern Mississippi.