Problem 27 - An Introduction to Physical Science

Question

Name a well-known synthetic fiber that is a polyester and one that is a polyamide. Name two addition polymers.

Step-by-Step Solution

Answer

Polyester: PET; Polyamide: Nylon; Addition Polymers: Polyethylene, Polypropylene.

Step 1: Identifying a Polyester

A well-known synthetic fiber that falls under the polyester category is polyethylene terephthalate, commonly known as PET. It is used in clothing and as a material for bottles and containers.

Step 2: Identifying a Polyamide

A well-known synthetic fiber that is a polyamide is nylon. Nylon is widely used in clothing, ropes, and fishing lines.

Step 3: Finding Addition Polymers

Addition polymers are made from monomers which add to each other without any byproduct. Two common examples of addition polymers are polyethylene, used in plastic bags and bottles, and polypropylene, used in packaging, textiles, and reusable containers.

Key Concepts

Polyester

Polyesters are a group of synthetic fibers known for their versatility and durability. A common example of a polyester is polyethylene terephthalate (PET). PET is renowned for its wide application range, particularly in the textile industry where it's used to create fabrics that are strong yet resistant to wrinkling and shrinking.
This makes polyester fabrics particularly popular for clothing that requires frequent washing.

• Polyesters are formed through a chemical reaction known as polymerization, involving an organic compound and an acid.
• The resulting fibers are not only long-lasting but also resistant to environmental elements such as sunlight and insect damage.

Beyond clothing, PET is also extensively used for making bottles and containers due to its excellent strength and transparency characteristics. These attributes help not only in preserving the contents but also in making them easily visible, which is particularly useful for consumer goods.

Polyamide

Polyamides are another category of synthetic fibers, with nylon being the most well-known member.
Nylon made a significant impact when it was first introduced due to its silk-like feel and high strength. This material quickly became a staple in both consumer products and industrial applications.

• Nylon is made through a process called polycondensation, which involves the reaction between diamine and dicarboxylic acid.
• Its toughness, elasticity, and resistance to oil provide nylon with a vast array of uses.

Common uses of nylon include the manufacturing of clothing items like hosiery and swimwear, as well as various kinds of ropes and fishing lines.
Its ability to withstand different strains without tearing makes it ideal for products that require long-lasting materials.

Addition Polymers

Addition polymers are an essential class of polymers that are created through the addition polymerization process.
This process involves monomers, which are smaller molecules that combine to form a longer polymer chain without producing any byproducts.

• Common addition polymers include polyethylene and polypropylene.
• These polymers are known for their stability and strength, making them suitable for a wide range of applications.

Polyethylene, for example, is a highly used polymer found in everyday products such as plastic bags and bottles. Its versatility relies heavily on its chemical resistance and low cost.
Similarly, polypropylene shares these traits and is often chosen for packaging, textiles, and even household items due to its robustness and flexibility.