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The Future is Plastic ... Bridges
ches_grin writes "BusinessWeek reports on the latest in bridge-building technology, where new materials and techniques are allowing bridges to be built in places that were previously thought impossible. New plastics are allowing bridges to be lighter and stronger than concrete, and 'using cables and new suspension techniques, these bridges traverse bodies of water that were once too deep, too soft-floored, or too earthquake-prone for conventional methods.' The article also includes a slideshow of some of the most innovative bridges, some still under construction."
The future is Spell.... Checkersq.
As someone who works in this field ("I am a polymer chemist" blah blah blah), you hit it right on the head regarding recyclability.
The main problem regarding the recycling of most plastics is that it's currently a heckuva lot cheaper to make new plastic from raw materials than it is to recycle existing materials. For example, soda bottles consist of several layers, each engineered to be slightly different: One layer prevents oxygen from entering the bottle, one prevents carbon dioxide from leaving the bottle, one layer has an antibacterial component to keep microscopic bugs from feasting on the sugars inside, etc. These layers have to be separated during the recycling process, and added complexity increases the cost.
Most plastic raw materials are byproducts of oil refining, and as the price of oil rises, so does the price of plastics -- we'll probably see more of a push to recycle in a few years.
Even thermoset (or thermoformed) plastics can be recycled to a small extent. While they cannot be repolymerized into new materials, they can be shredded and used in things like new plastic composites, rubbers and asphalts. Not to mention that there's a push in R&D to design new alternatives to thermosets that have comparable strength, but can be chemically degraded and reused.
-- The other Dr. Phil