Have you ever given thought to how you store rubber? It’s more than just putting it away in a box or a shelf and letting it sit until it’s needed. When less-than-ideal conditions are present, it can degrade the quality of the rubber or even ruin it completely. Read on to find out the environmental and storage factors that can impact rubber performance and how to avoid those issues.
How Storage Impacts Rubber’s Performance
Inside some types of rubber are active compound ingredients. These can include fillers, like carbon black, that improve its physical strength and ability to resist tension, as well as its capacity to withstand scraping and erosion (known as abrasion). There are also curing agents, which are chemicals that make rubber into an elastic material (a process known as vulcanization); these agents include sulfur, peroxides, and metal oxides. Altogether, these compound ingredients allow rubber to gain specific desired qualities or improve its ability to be processed.
Improper storage conditions can reduce the effectiveness of these compounds. For example, ozone sources lead to rubber cracking and reduced resistance because of their negative impact on rubber’s chemical structure. Heat and oxygen are similar in that they break down rubber’s internal structure to make the material weaker over time. Poor packaging can cause the plasticizers that keep rubber flexible to become stiff. All of these factors can reduce the lifespan of rubber before it’s even used.
The Factors of Storage
Temperature, whether hot or cold, is a major factor to consider. Increased temperature quickens the rate at which rubber deteriorates, while colder temperatures can stiffen rubber and make it prone to cracking. A rule of thumb for storage temperature is for it to be between 40ºF and 80ºF (4ºC and 27ºC). Similar in nature is humidity; a high or low amount can lead to deterioration via mold formation or chemical degradation. With air on the mind, so too should be good ventilation; when it’s improperly done, it means ozone and heat are trapped and humidity rises, which all negatively affect the stored rubber.
Rubber in storage should avoid oils, fuels, and solvents, among others, as these can cause chemical contamination and weaken the internal structure of rubber by causing it to swell or soften. Exposure to light, whether from artificial lighting or directly from the sun, can also negatively affect rubber and cause structural failure; rubber should be placed in non-transparent packaging so sunlight cannot enter the storage area or container.
Best Practices for Rubber Storage
Aside from the factors mentioned above, there are some general rules of thumb for storage. Avoid stacking rubber because this can make it deformed or warped; instead, place it flat in an area free of tension and that allows it to relax. Storage areas should be kept dark, cool, and dry, so sunlight, temperature, and humidity don’t deteriorate the qualities of rubber, and to prevent the formation of mold.
When you do use rubber in storage, go with the oldest ones you have instead of the newest. This helps you move more efficiently through your inventory and ensures that you have a fresh supply of new and old, as well as using older rubber before it degrades or expires. If you have rubber stored in packaging, make sure it’s sealed as tightly as possible to avoid ozone, chemicals, or less-than-ideal air conditions from entering the package and negatively impacting the rubber.
There is also a set of storage guidelines that, although technical, can be a resource. If you’re interested, you can read about them here. In short, there’s AS5316 (an aerospace standard preferred in North America), which focuses on the data recording, packaging, and storage of rubber; and ISO 2230 (an international, broad standard for all rubber products) with similar prioritization.
Both standards recommend a controlled environment for storage (like the removal of chemicals incompatible with certain types of rubber), but AS5316 emphasizes the rotation of stock as mentioned in the above section, while ISO 2230 is more stringent with stricter storage temperature and humidity recommendations.
There’s More in Store
Knowing the type of rubber you’re using is as important as storing it properly. That’s why we have all types of seals at our disposal for you. And if you have any questions or want to partner with us on your next project, reach out!