Does Polyester Shrink?

Polyester Durability

When it comes to synthetic fabrics polyester is a favorite among manufacturers and consumers. Its durability, affordability and versatility have made it a staple in many industries from fashion to home furnishings. But one question always pops up: does polyester shrink? As more people look for fabrics that require less care, understanding how polyester behaves to heat and washing becomes important.

This post will get into the details of polyester, debunk some common myths, and give you the inside scoop so you can choose and care for this fabric with confidence.

Does Polyester Shrink? The Science

Polyester unlike many natural fabrics like cotton or wool, is a synthetic fiber created through a chemical reaction of coal, petroleum, air and water. One of its best features is its durability. But does polyester shrink? The short answer is: in most cases no.

According to the American Association of Textile Chemists and Colorists (AATCC) polyester is classified as a “thermoplastic” material meaning it has a high melting point and low heat retention. This makes polyester resistant to shrinkage under normal washing conditions. Polyester fabric can withstand temperatures up to 230°F (110°C) without any changes to its structure. For comparison, cotton shrinks at 140°F (60°C).

But under extreme conditions – high heat or direct heat sources – polyester can shrink slightly especially if combined with natural fibers. So let’s get to the next factor: heat.

Heat and Polyester

Polyester’s durability and shrink resistance is all about how it’s washed and dried. As mentioned earlier polyester is a thermoplastic and while it doesn’t shrink under normal heat it can compromise its structure under prolonged high temperatures.

Polyester starts to distort at 300°F (150°C) according to the International Fabric Institute’s textile guidelines. This happens when it’s ironed without protection or dried on high heat. But for everyday use, polyester is heat resistant and rarely shrinks even after multiple washes.

To avoid heat induced shrinking follow the manufacturer’s care instructions which usually recommend washing polyester at cooler temperatures – ideally below 104°F (40°C) – and tumble drying on low.

How to Care for Polyester to Prevent Shrinking

While polyester is generally shrink resistant proper care will keep it in better condition for longer. Whether you have 100% polyester garments or a blend keeping your fabric safe from damage is easy.

Here are the essential tips to prevent shrinking:

1. Wash in Cold Water.
2. Tumble Dry on Low.
3. Polyester can be tumble dried on low heat. Don’t use high heat to keep the fabric from shrinking.
4. Avoid Ironing Directly:
5. If you need to iron polyester do so on the lowest heat or place a thin cloth between the iron and the fabric to avoid direct heat.
6. Use Mild Detergents:
7. Strong chemicals in harsh detergents can break down polyester’s fibers making it weaker and more prone to shrinkage over time.
8. For delicate polyester garments air drying is the best option. It prevents exposure to heat and keeps the fabric looking good for a longer period.

Blends with Polyester: Do They Shrink Too?

Polyester is often blended with natural fibers like cotton, wool or rayon to improve its feel, appearance and wearability. When combined, the properties of polyester change and this raises the question: do polyester blends shrink?

The answer is largely dependent on the percentage of natural fibers in the blend. For example, a 50/50 blend of polyester and cotton will shrink more than 100% polyester but less than 100% cotton. According to the Fabric Care Institute cotton shrinks 3% to 5% on average while polyester-cotton blends shrink 1% to 3% depending on how they’re washed.

A polyester-wool blend on the other hand is very prone to shrinkage due to wool’s sensitivity to heat and moisture. In these cases care instructions become even more important. Cold washing and air drying are two simple ways to keep these fabrics in their original shape and size.

Polyester’s Versatility and Shrink Resistance

So does polyester shrink? Under normal conditions polyester’s synthetic structure makes it shrink resistant. The fabric’s resistance to heat, water and wear makes it perfect for clothing, home furnishings and industrial applications.

But like any fabric, polyester isn’t invincible. High heat and improper care can cause some shrinkage, especially in blended fabrics. With the right washing and drying methods you can keep your polyester garments in great condition for many years.