“Water and air, the two essential fluids on which all life depends, have become global garbage cans.”

 

–Jacques-Yves Cousteau, Legendary French Oceanographer

 

 “I only feel angry when I see waste. When I see people throwing away things we could use.”

 

–Saint Mother Teresa

 

“Preserve and cherish the pale blue dot, the only home we’ve ever known.”

 —Carl Sagan

 “Plastics.”

 

Advice from Mr. McGuire to Dustin Hoffman’s Benjamin, he only had one word for the young

college graduate.  Movie, The Graduate, 1967.

 

“Plastic pollution is a global issue: killing wildlife, contaminating our oceans and waters, and lasting far longer than it is used.”

 

–Leonardo DiCaprio, actor and environmental activist. 

 

Plastic is a recently developed material. Before World War II, plastic was not very common. Now plastics are everywhere. Plastic bags are in our oceans and streams. Plastic toys are in our trash and landfills. We are in the midst of the Plastic Age.

The planet has endured other stages of human development. The Stone Age was a prehistoric period during which stone was widely used to make tools with an edge, a point, or a percussion surface. The stone age lasted for roughly 3.4 million years, and ended between 4,000 BC and 2,000 BC, with the advent of metal working.[1]

The melting and smelting of copper marks the end of the Stone Age. In Western Asia, this occurred by about 3,000 BC, when bronze became widespread. The term Bronze Age is used to describe the period that followed the Stone Age.

The third period of human development is known as the Iron Age.

 

The duration of the Iron Age varies depending on the region under consideration. It is defined by arch-aeological convention. The Iron Age began when the production of iron or steel has advanced to the point where iron tools and weapons replace their bronze equivalents in common use.

The Bronze Age is a historic period, lasting ap-proximately from 3300 BC to 1200 BC, characterized by the use of bronze, the presence of writing in some areas, and other early features of urban civilization.[2] The Bronze Age is the second principal period of the three-age system proposed in 1836 by Christian Jürgensen Thomsen for classifying and studying an-cient societies and history.

 

An ancient civilization is deemed to be part of the Bronze Age because it either produced bronze by smelting its own copper and alloying it with tin, arsenic, or other metals, or traded other items for bronze from production areas elsewhere. Bronze is harder and more durable than the other metals available at the time, allowing Bronze Age civilizations to gain a technological advantage.

While terrestrial iron is naturally abundant, the higher temperature required for smelting, 1,250 °C (2,280 °F), in addition to the greater difficulty of working with the metal, placed it out of reach of common use until the end of the second millennium BC. Tin’s low melting point of 231.93 °C (449.47 °F) and copper's relatively moderate melting point of 1,085 °C (1,985 °F) placed them within the capabilities of the Neolithic pottery kilns, which date back to 6,000 BC and were able to produce temperatures greater than 900 °C (1,650 °F).[3] Copper and tin ores are rare, since there were no tin bronzes in Western Asia before trading in bronze began in the 3rd millennium BC. Worldwide, the Bronze Age generally followed the Neolithic period, with the Chalcolithic serving as a transition.

Bronze Age cultures differed in their development of writing. According to archaeological evidence, cul-tures in Mesopotamia (cuneiform script) and Egypt (hieroglyphs) developed the earliest practical writing systems.

 

The Plastic Age

 

We are now in the Plastic Age.  While stone, bronze and iron are minerals, their use does not significantly adversely affect the environment.

 

History of Plastics

 

Plastic is a word that originally meant “pliable and easily shaped.” It only recently became a name for a category of materials called polymers. The word poly-mer means “of many parts,” and polymers are made of long chains of molecules. Polymers abound in nature. Cellulose, the material that makes up the cell walls of plants, is a very common natural polymer.

Over the last century and a half, humans have learned how to make synthetic polymers, sometimes using natural substances like cellulose, but more often using the plentiful carbon atoms provided by petro-leum and other fossil fuels. Synthetic polymers are made up of long chains of atoms, arranged in repeating units, often much longer than those found in nature. It is the length of these chains, and the patterns in which they are arrayed, that make polymers strong, light-weight and flexible. In other words, it’s what makes them plastic and pliable.

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