Why Do Shoes Shatter?

When it comes to shoes, no one wants their shoes to fall apart. When this happens, the design of the shoe suffers and loses the desired effect for your foot. So, why do shoes shatter?

Why Do Shoes Shatter?

The three types of soles begin to unravel in the following ways:

1. Polyurethane sole – due to hydrolysis
2. Rubber soles – when the chemicals start to dry, the soles can become brittle and cause cracks
3. EVA sole – through repeated shocks while walking or running

Shoes break down when they are made of certain materials, they can become porous and soft if not worn, and you store them in a pantry or closet for long periods of time. It can cause holes, cracks, and eventually collapse. This is due to the chemicals in the rubber that makes the shoe softer. This can happen when you leave your shoes in a closet or closet for an extended period of time. Moisture and heat react with chemicals in the rubber and begin to degrade. It can cause holes, which can lead to cracks in the sole. This chemical deterioration also occurs when too much water is used on rubber soles, as it removes the plasticizers that protect them. Soles made of plastic PU are easily decomposed due to the oxidation of the polymer chains.

Why Does the PU Sole Disintegrate?

Polyurethane soles are flexible, slip-resistant, lightweight, and pressure-resistant, which is why they are used in boots, dress shoes, and safety shoes. For these reasons, manufacturers still use PU material in their shoes.

The reason for the deterioration of polyurethane soles is the internal structure of the material. PU materials are composed of long-chain polymers that change when exposed to moisture, heat, and sunlight. This process is stimulated when shoes with PU soles are stored in damp places or exposed to wet surfaces for extended periods of time. Moisture breaks down these long polymer chains, weakening them, and the material begins to delaminate.

To prevent the shoe’s polyurethane sole from breaking down, store the shoe in a cool, dry place with good ventilation. Airflow prevents moisture from accumulating in the sole. Never store them in high humidity or excessively high temperatures, and do not leave them in the sun for long periods of time. This is the most effective way to prolong the life of polyurethane soles. Storing polyurethane soles in a dust-free environment will also ensure they stay in new condition longer. Also, keep your feet dry when wearing shoes and clean the soles every two weeks.

Why Does the EVA Sole Dissolve?

EVA soles generally do not chip. Compared to PU foam, EVA foam is more compressible and has less abrasion resistance. The reason for the disintegration of EVA foam soles is not the same as that of PU soles. Ethyl acetate is very soft foam. Unlike PU, EVA does not hydrolyze. It doesn’t have an internal structure like polyurethane, and if left in a closet for a long time, it will shatter under high humidity. If the soles of your EVA-soled shoes wear out quickly, you’re most likely wearing them on rough surfaces that are peeling foam.

Because EVA is highly compressible, constant stress and friction can cause it to lose support and compactness over time. For these reasons, EVA foam has the potential to wear out.

Will Leather Shoes Deteriorate if They Are Not Worn for A Long Time? 

No, leather shoes do not have “durability”. In other words, if you don’t wear them, they won’t go bad. The leather dries out and becomes stiff. Even if it has been damaged by water before, over time the moisture should dry out and the shoes should return to their normal state, where they can take on shape and flexibility.

Wearing your shoes regularly is certainly the best way to keep your shoes soft, but it’s not always possible. Dry brushing with a soft brush occasionally helps keep the leather soft. Vacuuming (with a brush attachment) is also helpful as it protects against dust mites and other allergens. Wiping them with a damp cloth is also beneficial, but make sure they are completely dry before putting them away. The more often you get them wet, the quicker they will dry and harden.

After a week or two, apply a leather conditioner to shoes and leave it on for at least five minutes. Wrinkles and fine lines disappear quickly. You can then buff them with a dry brush to ensure any excess conditioner is removed from the surface of the shoe.

How Long Can the Shoes Be Stored?

Shoes can last 5 to 10+ years if you keep them in a controlled environment. PU materials typically begin to degrade after 5 to 6 years in the closet. If the sole is completely chipped, like the PU material, you may need to replace the sole. The rubber sole that sticks to the upper has a durability of about 8 to 10 years.

If the shoes are made of rubber and you leave them unused in a closet for a long time, the glue will begin to dry out and stop doing its job of bonding the sole to the upper. If this is the case for you, you can use shoe polish to glue the severed areas on the shoe if there is only a slight separation.

To prevent the glue from the base from evaporating, vacuum sealing is the best method. The following is a comment from a netizen on the forum:

• The glue in every 10-year-old pair of shoes will evaporate if not stored properly. Whenever you’re going to collect shoes that you won’t wear very often, I think vacuuming is the best strategy. I’ve had near-perfect vintage Air Tech Challenges from the early ’90s thanks to the vacuum seal. I also have a pair of Vapor 9 grass pitches which I also seal.
• For leather shoes, use a shoe last or shoe last for storage. This will prevent the leather from wrinkling. Also remember to never leave your shoes in direct sunlight for too long as this can cause the sides of the soles to dry out and become brittle, which can cause a lot of damage if left untreated.