Final answer:
Nylon and polyethylene are examples of synthetic polymers with distinct properties such as toughness and flexibility respectively. Nylon is used in products requiring high strength, while low-density polyethylene is used for packaging.
Step-by-step explanation:
Two examples of synthetic polymers are nylon and polyethylene. Nylon, known for its silky fibers and toughness, was extensively used during World War II for parachutes and ropes due to its strong and light properties. The monomers in nylon are linked by amide bonds, which create polymer chains that are resistant to stretching. Kevlar, which is derived from nylon by replacing -CH₂- units with aromatic rings, results in an even stiffer and stronger material used in applications that require high durability and strength such as bulletproof vests and armor.
Another synthetic polymer is low-density polyethylene (LDPE), which is known for being softer, more flexible, and having a lower melting point compared to other grades of polyethylene. This variation in properties is due to the higher number of branches in its polymer chain structure. LDPE is widely used in packaging materials such as plastic bags and film wraps.