Rubber shoes are always vulnerable to the infamous plague of cracking. This always makes a footwear uglier as the crack keeps multiplying.
Understanding the science of rubber, it is important to know that some of our innocent practices are the major causes of these.
Let’s take a look at 8 ways to prevent your rubber shoes from cracking.
- Always store rubber shoes at room temperature
- Avoid exposing rubber shoes to UV light
- Wash rubber shoes with mild cleaners
- Keep conditioning to a minimum
- Store rubber shoes in airtight locations
- Brush to one direction
- Dry your rubber shoes naturally in a well-ventilated area
- Avoid too much wetness on the rubber shoes
Store rubber shoes at room temperature
If you store rubber in the refrigerator, it will crack. This is one of those things like putting your butter in the freezer.
Some people claim that it makes it last longer, but I suspect that if you ask them to demonstrate, they’ll tell you to cut off a slice and try it. (It tastes like butter.)
But this works for rubber. If you keep rubber at room temperature, it will not crack. I keep my old bike inner tubes crumpled up in a corner somewhere; they’ve been there for years and are still good.
(This contradicts what you will read elsewhere on the Internet, which is that refrigerating rubber protects it from heat expansion and therefore prolongs its life.)
Rubber is a polymer, which means it is made of giant molecules. The giant molecules in rubber are chains of linked atoms, mostly carbon and hydrogen.
The chains are too big to fit in the spaces between the floorboards or the cracks in your driveway; they would bend or break if you tried to store them there.
Avoid exposing rubber shoes to UV light
The solvent used to cure the rubber in many shoes is a good solvent for some plastics, too, which means that some of the dyes are dissolved out of the shoe.
Exposure to ultraviolet light accelerates this process. A few weeks of California sun can turn your white shoes yellow.
Under fluorescent lights, the UV-absorbing chemicals in most shoe finishes are not effective, because they are designed to protect against visible light rather than UV.
So, if you do most of your walking indoors, or under cloudy skies, or at night, your shoes will last longer without special treatment. If you do spend time outdoors, you’ll want some kind of protection.
There is a solution to this problem, but it applies even in situations where you can’t really control the light exposure.
What’s needed is a way to bond the rubber molecules back together again. And that is what happens in tires.
I’m not sure how tires do it, but I do know that one thing that helps is physical movement. That’s why you are less likely to get blisters on your feet if you are running or dancing or doing aerobics than if you are sitting still.
Tires move when they are driven, which helps expose the rubber to moving air, and I suspect that this enhances the chemical reactions that heal the cracks.
Wash rubber shoes with gentle cleaners
You can prevent the rubber from cracking. Washing the rubber with a gentle cleaner will remove the surface layer of dirt and any residue from manufacturing. This will help to reduce the cracking of your rubber shoes.
The first step is to thoroughly rinse the shoes under warm water, removing any dirt or debris that may be clinging to them.
Then fill a sink or bathtub with warm water and add your favorite gentle cleaner. Submerge your shoes in the cleaning solution, making sure they are completely covered.
Rubber is porous. If you leave it dirty, it will get dirty inside. Even the dirt on the outside will eventually work its way in.
You can tell when this happens because rubber that was once soft will have developed hard spots.
Some chemicals are less harmful to rubber than others are. If you wash your rubber shoes with ammonia or bleach, they may turn yellow or brittle or crack, but at least they won’t get dirty inside.
The crack in the shoe above is from an ammonia attack, not from wear and tear.
I don’t think it is necessary to go to this extreme, though. Most soaps will clean your rubber well enough if you use hot water and don’t leave the shoes in the water for hours.
Use a stiff brush to scrub off any caked-on dirt, then rinse the shoes thoroughly under hot water.
Hot water melts soap suds better than cold water does because there’s more energy in hot water to help break up the suds into individual molecules.”
Keep conditioning to a minimum
The best way to keep your shoes soft is not to wear them. The more you do, the harder they will get. Duck shoes (rubber over canvas) are made to be used like that, and they can last for years without hardening.
But if you like duck shoes but can’t wear them because you have to wear something else, there are still some things you can do.
The first thing is to avoid conditioning altogether. Porous shoes can soak up conditioning wax better than dense ones, so the less porous your shoes are, to begin with, the less conditioning they will take.
You can use a toothbrush or a shish-kebab skewer or a similar hard implement to remove as much of the wax as possible before it gets sticky. Also, wipe off your laces whenever they get dusty — that’s where most of the dust really collects.
If your shoes are already very soft, though, conditioning will make them harder rather than softer.
To restore their softness, stop applying conditioning immediately and wash out what you applied before it gets sticky.
Then make sure you only condition once every month or two instead of every day and condition evenly rather than concentrating on high-wear areas.
Shoes can be damaged by excessive exposure to light, heat, and moisture. The light causes the colors to fade; the heat and moisture cause the leather to dry out and crack.
When shoes are new, their natural oils help preserve them. But once they have been worn a few times, the oils are gone and it is time to nourish them.
You can buy shoe lotion at shoe stores or online. Use it sparingly; you don’t want your shoes to smell like a salad bar.
Conditioning doesn’t restore the original suppleness of leather – nothing can do that – but it does at least keep your shoes from getting stiffer with each wear.
Store in airtight places
If you must store rubber objects in the basement, there are ways to control humidity. One is to place the objects in airtight containers. Another is to use a silica gel pack placed in the container with the object.
The silica will pull moisture out of the air. You can buy silica gel packets at craft stores, where they are used to keep polymer clay from drying out.
If you have a lot of rubber shoes or other objects that need controlling, you can get a larger bag filled with silica gel at a home supply store.
The silica itself should not come into contact with the objects. It’s fine for it to be inside an airtight bag, but if you put it inside any kind of cloth or paper wrapping, make sure that no part of it touches the object itself.
One of the most useful pieces of advice I ever got was to keep my rubber shoe in a Ziploc bag.
If you’ve ever wondered why, the reason is that rubber is sensitive to a lot of air.
The result is a hardening of the material, so it gets less flexible and stops being rubbery.
That’s what happens when you leave your rubber boots out in the sun for too long: the boot material starts to crack because it has started to cure.
So if you put your rubber boots into an airtight container, they won’t be exposed to ozone from the air — which will make them last longer.
You can extend their lives further by keeping them at a low temperature since air attacks slowly at lower temperatures but still faster.
Brush to one direction
The best way to prevent your rubber shoes from cracking, and protect your shoes? Just brush the rubber in one direction.
The reason for this is that when you brush in one direction, the treads will be arranged in a single layer. This prevents the cracks to open too wide and keeps them from spreading.
When you brush in the opposite direction, the treads will be inclined to stack up, which will let the cracks spread faster, and makes it more likely for them to reach all the way through.
This tip works best on new shoes. After some time of use, you can still try it out on old shoes, but it does not work as well as on brand new ones.
Rubber is a polymer, which means it is made of long strings of molecules chained together. When the rubber dries, it shrinks a little bit, and the chains get a little bit tangled.
I have never been able to figure out why people put so much effort into preventing this process from going too far.
The best way to keep the rubber from cracking is to make sure the chains go in only one direction. If you brush your rubber shoes in one direction, they will last longer.
Try brushing in different directions when you clean them and see how much longer they last when you brush in one direction.
Dry naturally in a well-ventilated area
An interesting way in preventing cracking is to make sure the shoe dries slowly. Next time you buy rubber shoes, look at them when you get them home.
Notice that the insides are wet, not just from sweat but also from the glue. This glue is what causes cracks in rubber-soled shoes.
The slow drying of the glue causes the shoes to shrink slightly, and when they do, the glue pops apart.
The key to fixing this is to let your shoes dry slowly. If you can hang your shoes somewhere warm, so much the better; don’t dry near a heat register or radiator.
But if your apartment is too cold for that, it’s OK to let them dry by themselves in a well-ventilated area.
The important thing is not to let them dry near anything hot—like a radiator or an air conditioner—or in direct sunlight.
If you have just bought new rubber shoes, don’t wear them for at least two days, so that they have time to dry without being walked on.
And remember that you can’t remove cracked soles by sticking them in the oven; if you try it, you’ll probably destroy the shoe entirely.
Shoes made of natural rubber, such as sneakers and sandals, can dry up and crack in a matter of months.
One obvious solution to the general shoe drying problem would be to keep your shoes in a controlled environment that has little or no humidity.
You could keep them in an airtight container, like a Ziploc bag, but that isn’t very practical for most people.
Many people believe that using silica gel packs will help prevent shoes from drying out.
Avoid too much wetness
Rubber shoes will crack and split if they get too dirty and too wet consistently. If you want to prevent your rubber shoes from cracking, firstly you must wash them with clean water and then let them dry naturally.
Rubber is a unique material that is the most elastic substance on earth. It is also quite tough and durable.
Do you remember that old legend that rubber shoes will not be damaged even if you wear them every day for more than 10 years?
You can also use them as long as you like for heavy manual work such as farming, construction work, or gardening. This will only be hampered by too much exposure to moisture.
Before wearing the boots, you should firstly brush off any dust or dirt with a soft cloth.
During winter, the rubber surface on the boots is usually covered with ice, snow, and mud which makes the boots heavier and more difficult to walk in.
Before wearing the boots, you can use a brush to lightly brush off any mud or dirt from the surface of the boots.
To prolong the lifetime of your rubber boots, you should try to avoid walking in puddles or standing in water for prolonged periods of time with your rubber shoes on.
The key factor to keep your rubber shoes from cracking is to keep them dry at all times.