Material Studies | Longevity & Decay

Just imagine opening a box you believed to have been safely stashed away years ago, only to open it and be confronted with this sore sight. At the time of storing, the motive was brilliantly logical. The Air Jordan XVII was a slept on release, even in this Wizards colourway. Sitting on a pair for some years to come would be an investment for the future. The chance to break out some deadstock Jordans from past gone years is a privilege of a few and in the instance of re-sale a true money spinner (corgieshoe). The sad reality is the process is by no means an exact science. In more cases than not the result is what you see above - a deadstock pair of sneakers going to waste having never seen the light of day.

As I may have hinted at already, keeping your sneakers deadstock or not is a choice that every sneaker enthusiast faces with each and every new purchase. There is no denying that a pair of sneakers looks best fresh out of the box, without a crease in the toe box or the slightest hint of dirt on the outsole. Sometimes, our love of sneakers takes things to levels that we would have never seen coming at that point of first purchase. We are all culpable of wishing eternal life for a special limited edition/ release, ever hoping that the arrival of a new day will bring with it the holy of holy's, the news of the discovery of the elixir of youth for our kicks. The truth is that wether you keep them on ice for years or wear them everyday, the inevitable will happen. They will end up cracked, crumbled, peeling, ripped, stained, torn and above all unwearable. If you want to look at them forever in their pristine state, just take a picture and then wear them so celebrating their transient grace. Sneakers are simply not made to last and it is the materials, not the design, that we can hold accountable for that. 

Let's get into the science of it!

Without breaking down the entire composition of a sneaker into its individual architectural elements there are four major material groups that pose the main problems for any collector. These are textiles, leather, rubber and plastics. A simplistic approach to taxonomy as this does not make plain the susceptibility that each category faces to the weathering effects of time. Thus the grouping of the material types will be done in descending order of durability. This will mean staring with the with the most durable and ending with the least durable. So, introduction aside it's time now for the nitty gritty.

Textiles and Leather:

The reçurent culprits to much material damage are sunlight and weather cycles. The simple science of this is that excessive sunlight bleaches colour pigments whilst the fluctuation of temperature and moisture content leads to the excessive expansion and contraction of cell structures. This in turn causes them to break precipitating a subsequent loss of strength in the material. 

Had you ever been tempted to apply a dressing to the premium leather of your bespoke Nike Air Force One or OG Jordan then be warned. Not only is it slightly unorthodox behaviour but applied dressings, such as a saddle soap, are fine whilst the object is in use. Let me just stress that again - IN USE. This is because the shoe is usually cleaned and a new dressing reapplied on a regular basis. Once this regular maintenance ceases, however, dressings often start to migrate to the surface where they form a sticky surface layer that attracts dust, etc. The worst bit is that this residual layer of dirt is what supports mould growth that is irreparable. Thus be warned any time you consider adding some form of protective dressing to your kicks.  

Rubber and Plastics: 

This is where things start getting a bit tricky as at this point the temptation is to fall into the trap of being overly scientific and thus boring people to tears. So, I have tried to keep the unadulterated science of it all to a manageable level and more importantly a relevant level.

Rubber is a very enigmatic material, in respect to its deterioration. Two apparently identical rubber components in the same environment can behave totally differently. One component may become brittle and cracked, whilst the other may become soft and sticky. Unlike most other materials, rubber tends not to be adversely affected by chlorides (acids). That means touching them with your sweaty hands with not cause any longterm damage. After all someone would have told NBA athletes to stop wiping their sweaty hands on the soles of their sneaker during games. Most importantly of all no real damage with be subjected on them by walking in the dirt of pavements and streets worldwide that exists outside of the sanitised world of the shoe box. 

At this point I'm quickly going to digress but it is all for good reason. To give a flavour of why new sneaker releases are full of new materials that we have never heard of is because there are over 2 million different types of plastics (and rising) that designers can choose between. What more, many materials can be added to plastics. For sneaker designers it is a means to improve the performance of the shoe. For instance to counter brittleness and impart elasticity plasticisers are used. To lower cost and to add strength bulking agents and fillers are used. For the increased longevity of the sneaker, stabilisers can be added to counter the effects of UV light, to prevent fungal attack or most commonly to reduce the rate of oxidation. 

Digression aside, probably the principal cause of deterioration of rubbers and plastics is sunlight. The composition of sunlight is such that its various wavelengths can cause different types of damage in different plastics. Basically there are two main types of damage - chain scissoring and cross-linking. Chain scissoring occurs when enough energy is absorbed to break bonds in the polymer chains. This results in a weakening of the plastic. For the sneaker head it is often observed as cracks or chalkiness of the surface of any part of the sole (usually the mid sole). Cross-linking occurs when absorbed energy promotes the formation of new bonds within the structure. Over time this can result in a plastic becoming insoluble in solvents that it was originally soluble in. More relevant to sneakers it can also result in the plastic becoming less flexible and elastic. This explains why that pair of OG Jordans disintegrated on the first time of wearing them after multiple years of proud display. 

What I fear is that in light of all this science some readers may read this article as an act of scaremongering. Worst still they might read too much into it. Worst of all I might have driven them to such insane measures as this....

If you have reached this stage of insanity then there is simply no help nor way back to normality. But as good an action as any to avoid the slippery slope to vac packing your entire sneaker collection is simply give them some air time. The beauty of this hobby of sneaker collecting is that everything comes back inevitably and you'll get another chance to re-stock on your favourite models and makers.