THE ANTHROPOCENE - Plastics and Environmental Sustainability - page 26

bio-inertness of plastics have made it the material of choice in a broad range
of applications. The demand for plastics is linked to economic development
of nations. With some conventional materials such as cement or steel, the
demand on materials is decoupled with economic development and is
decreasingonapercapitabasisindevelopedcountries.Thiscanoccurwhen
the gross domestic product (GDP) of the country becomes dominated by
the service sector (vonWeizsäcker et al., 1997). However, this is not the
case with plastic materials that continue to grow coupled and in tandem
with regional or national economic growth. The future supply of commodity
plastics is generally tied closely to that of fossil fuels. This need not
necessarily be the case as plastics can also be manufactured from renewable
resources, but the processes are as of yet not cost competitive. As petroleum
resourcescontinuetodwindle,thecostofplasticswillundoubtedlyincrease,
and recycling of some of these may become cost-effective.
Historically, the rate of growth of material consumption has outpaced that
ofpopulation.Duringtheperiod(1961-2012)thatsawapopulationincrease
of about 230%, that of wood, steel, and cement consumption grew by 160,
426, and 1100%, respectively. Plastics consumption in the same period grew
by over 4800%. 22 Plastics are so common a material that today it is difficult
to imagine living in a world with no plastics. If all plastics were
instantaneously removed from modern lifestyle, we would certainly miss
the material. Most of our clothing including footwear, consumer goods and
building products (plumbing, siding, some glazing, and electrical
components), parts of vehicles (some bodywork, all seat covers, lamps),
critical residential services (electricity, water/sewer, gas, telephone), most
packaging and healthcare products will fade away. Of course, some of these
can be substituted with other materials such as glass, metal, wood, or paper
but generally at a higher materials and life cycle energy costs.
There are several key characteristics of plastics that make them highly
competitive as a material in the marketplace and will guarantee its
continued growth:
1. Strength and low density
Plastics, though lightweight, are exceptionally strong materials. Some
specialty plastics such as Kevlar are stronger than steel and are used in
bulletproof vests. Carbon-fiber and other composite materials
(including nanocomposites) are used in transportation applications that
require lightweight and high strength. As will be elaborated in Chapter