Lack of Breathability
The biggest complaint most people voice about Polyester Flag Fabric is its lack of breathability. Polyester fibers, which are essentially plastic, do not facilitate airflow. Many people prefer the natural, loose weave of cotton that is far more breathable.

Lack of Moisture Absorption
While polyester does wick moisture away, its lack of breathability means that it does not absorb the sweat from a person’s skin. In hot or humid weather, polyester will often cling to your sweaty skin very unpleasantly.

Most athletic wear uses a poly blend to avoid this issue. Polycotton merges the moisture-wicking ability of polyester with the breathability of cotton. This mitigates the stickiness of 100% polyester and the dampness of 100% cotton.

Environmental Concerns
Environmentally conscious consumers list many valid concerns about the dangers of polyester.

The polyester production process involves a lot of energy and impacts greenhouse gasses. On top of that, any product made from fossil fuels is not sustainable.

Polyester is also not biodegradable. Some studies indicate that polyester fabric will not degrade even over a period of 50 years!

Finally, the cheap, easy production of polyester definitely boosts quick fashion. This adds to the problem of fashion waste. How many of you have bought a cheap dress for a special occasion, and thrown it out a year later when you no longer needed it?

Flammability
While polyester has a high burn point, it does melt more easily than you might think. This can cause serious injuries. If polyester melts onto you, it will actually fuse to your skin and will require professional medical treatment.

In less scary but still annoying circumstances, polyester will melt under high iron settings. It can also become mishappen if your dryer heat is set too high.

Holds odors
Because it lacks breathability, polyester can hold onto odors. It’s also tricky to get grease and oil stains out of polyester.

Comfort Issues
Obviously, polyester’s lack of breathability can impact comfort. People also complain that polyester can hold a static charge, causing issues with static electricity (if you have long hair, you have probably taken off a winter coat and watched your hair stand straight out from your head as it clings to the coat!).

Some polyester blends are prone to pilling as well. Pilling is that thing where a little bump of loose thread breaks free from the weave and appears on the surface of the fabric.

Health Concerns
Polyester fabric is non-hypoallergenic. It contains chemicals that can cause hormone issues and create skin allergies.

Some people also worry that the chemicals used in polyester production are dangerous in their own right.