The Properties of Plastics

The most important characteristics of plastics and polymers is their range of physical and chemical properties. They differ in flexibility, resistance to heat, transmission of light and tensile strength. These differences arise not only from differences among the various monomers used in polymerisation but also from differences that can be generated through the process of their production, the polymerisation process.

 
   
What are Elastomers?

Elastomers are polymers that stretch easily and return readily to their original shapes.

They can be twisted, stretched and compressed without damaging.

 
   
Descriptions of Earthquakes

"A bad earthquake at once destroys the oldest associations; the world, the very emblem of all that is solid, had moved beneath our feet like a crust over a fluid; one second of time has created in the mind a strong idea of insecurity, which hours of reflection would not have produced."
- Charles Darwin (reflecting on the devastating February 20, 1835, earthquake in Conceptió, chile)

"The Mount of Olives shall cleave in the midst thereof toward the east and toward the west, and there shall be a very great valley; and half of the mountain shall remove toward the north and half of it toward the south."
- Zechariah 14:4

"The earthquake began everywhere with tremors ...; then the great shove of the destructive shock arrived, in some cases rather before, in some a little after, the moment of loudeat sound, and it died away suddenly into tremors again."
- Robert Mallet; The Neopolitan (Italy) earthquake, December 16, 1857

 
   
Do Moonquakes exist?

An answer to this question has been provided by the space program. During several Apollo landings, beginning in 1969, several seismographs have been placed on the moon and the answer is: Yes, surprisingly, between 600 and 3000 tiny moonquakes have been detected every year.

 
 
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