What happens to synthetic fibers in high temperatures that affects their strength?

Synthetic fibers, when exposed to high temperatures, tend to soften and stretch. This is due to the molecular structure of synthetic materials, which are often made from polymers that can lose their rigidity as they are heated. The heat causes the polymers to become more pliable, effectively reducing the fiber's overall strength and making it susceptible to deformation when under load.

Softening can lead to a significant decrease in the fibers' ability to bear weight or resist tension. This behavior is crucial to understand in rigging and hoisting applications because the integrity of the lifting equipment is paramount; if synthetic fibers soften during operations, they could fail, leading to unsafe working conditions.

Other options may imply different reactions of materials to heat but do not accurately reflect the behavior of synthetic fibers. Understanding this characteristic is vital for ensuring safety and proper selection of materials in lifting and hoisting tasks.