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This article explores the world of plastics, detailing their origins from petroleum and natural gas through the extraction of monomers and polymerization. It differentiates between two main categories of plastics: thermoplastics, which can be reshaped with heat, and thermosetting plastics, which harden permanently. Additionally, the article highlights the advantages of using plastic in technical objects, including its moldability, durability, lightweight nature, and cost-effectiveness, making it a popular choice in various industries.
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2. Where does plastic come from? Plastics are made of molecules called polymers.Polymers are made up of chains of multiple molecules called monomers.
Polymer Monomer
2. Where does plastic come from? • Most plastic comes from petroleum or natural gas. • Monomers are extracted from these substances. • During processing, these monomers are linked together through chemical reactions.
2. Where does plastic come from? • Celluloid is used in the production of ping pong balls. • Celluloid is created by modifying natural polymers like cellulose. • Cellulose is a natural compound found in the cell wall of plants.
3. Plastics can be divided into 2 categories: thermosetting plastics and thermoplastics. What isthe difference is between these 2 categories of plastic? Thermosetting plastic • hardens permanently through heating • plastic is rigid Thermoplastic • softens when heated and hardens when cooled • can be reshaped
http://www.thedailygreen.com/green-homes/latest/recycling-symbols-plastics-460321#slide-1http://www.thedailygreen.com/green-homes/latest/recycling-symbols-plastics-460321#slide-1
5. What are some advantages to using plastic as a material for technical objects? • Easily molded • Can be made in various colours • Durable • Doesn’t rust • Lightweight • Inexpensive