Polymers Flashcards
What are polymers and how are they classified?
Polymers are large molecules made up of repeating subunits called monomers. They can be classified into synthetic polymers, natural polymers, and biopolymers.
What are some common synthetic polymers and what are their uses?
Some common synthetic polymers include polyethylene, polypropylene, polystyrene, PVC, and nylon. They are used in a wide range of applications such as packaging, textiles, automotive parts, and construction materials.
What are some common natural polymers and what are their uses?
Some common natural polymers include cellulose, starch, chitin, and silk. They are used in applications such as papermaking, textiles, and food packaging.
What is polymerization and how does it occur?
Polymerization is the process of combining monomers to form a polymer. It can occur through addition polymerization, where monomers with unsaturated bonds join together, or condensation polymerization, where monomers with reactive functional groups join together while eliminating a small molecule such as water.
What is crosslinking and how is it used to modify the properties of polymers?
Crosslinking is the process of forming covalent bonds between polymer chains. It can be used to modify the mechanical, thermal, and chemical properties of polymers, making them more resistant to deformation and degradation.
What is plastic deformation and how does it occur in polymers?
Plastic deformation is the permanent deformation of a material under stress. In polymers, it occurs when polymer chains slip past each other and become entangled, causing the material to become permanently deformed.
What is the difference between a thermoplastic and a thermoset polymer?
A thermoplastic is a polymer that can be repeatedly melted and solidified without changing its properties, while a thermoset polymer undergoes a chemical reaction during curing that makes it irreversibly solid and unmeltable.
What is the glass transition temperature of a polymer and how does it affect its properties?
The glass transition temperature is the temperature at which a polymer transitions from a hard, brittle state to a soft, rubbery state. It affects the mechanical, thermal, and chemical properties of the polymer and is an important consideration in material selection for specific applications.
