In this write up we will discuss the question “Is silicone biodegradable?”. We will provide you with a review by citing the material composition of silicone, its superior properties, its application in our day-to-day activities, and the role they play in safeguarding our environment.
Is silicone biodegradable?
The answer is no, silicone is not completely biodegradable at least not in the span of human life. Silicone is known to possess the molecular nature that makes it durable, physically strong, resistant to extreme conditions, and excellent resistance to abrasions.
All these properties contribute to the non-degradability of silicone. On the contrary, silicone is the best alternative to plastic. Its use is diverse ranging from adhesives to electronic items to kitchen appliances. Unless there is another magic material that can oust the benefits of silicone, it is touted as the best replacement for plastics.
Unlike plastic, silicone food packaging does not leach out any harmful chemical components to the material it contains. This allows for its reusability without harming any living beings in the surrounding area. Though silicone is not the best, it is a better choice because it can be reused and recycled owing to its superior properties.
What makes silicone non-biodegradable?
Silicone is made from widely available natural material found on earth called silica. Silica is found in abundance in soil; however, processing of silica is necessary to make silicon, the raw material for making silicone (with an “e”).
The processing of silicon to silicone further utilizes hydrocarbons which are obtained from non-renewable sources such as oil and natural gasses. Thus, being non-biodegradable and as a factor in depleting non-renewable sources, silicone does not provide a perfect solution for the choice of material, but it gives us an alternative to plastics for a better planet and healthy environment.
Though the process of making silicone is simple, what we get at the end is a highly durable and highly resistant to multiple factors such as high and low temperatures, chemicals, and physical abrasions.
Since usage of silicone products has increased in recent time, bacteria and fungi have not evolved to break down this heavy-duty material. Only time will tell the true negative effect of silicone to the environment.
The following points highlight the physical features of silicone that are superior to plastics.
Resistance of silicone to heat
Silicone has been tested for its resistance to heat and they have been shown to withstand as high as 450°F and as low as -100 °F for many hours. Thus, they are the preferred materials for making seals and gaskets that are required to withstand high temperatures.
On the other hand, they are used in freezers as silicone food-grade sealants and silicone bags due to their cold-resistant and waterproof properties.
Resistance of silicone to chemicals
Silicone products have outstanding resistance to solvents and chemicals. They are essentially unaffected by dilute acids and bases. However, they degrade severely by strong acids and bases which is usually difficult to attain through the natural degradation process and hence one more reason to mark silicone as non-biodegradable.
Use of silicone for a healthy environment
Unlike plastics, silicone does not easily break down or disintegrates and hence silicone particles are not ingested by wildlife or aquatic animals.
Reports have suggested that silicone is completely safe on land and water as it does not leach out any toxic chemicals nor does it easily break down to microparticles.
Silicone also has an added advantage of being a hygienic material as they are non-porous and hence materials do not accumulate on its surface. This makes the silicone a clean, smooth, and hygienic material to use for cooking purposes.
Because of these properties of silicone, it is much harder for microbes to act upon for the biodegradation process to happen. In short, silicone products act as an inert material that is tasteless, odorless and non-toxic making it an FDA-grade quality material.
How widely silicone is used?
Nowadays, silicone is used in a wide range of applications as well as household products. This wide application is attributed to the physical features of silicone products.
Kitchen spatula and holders made of silicone are highly resistant to heat and fluctuating temperature. Lunch boxes made of silicone are microwavable without the fear of release of any toxins that plastics are known to have.
Due to its high-performance nature, silicones are used in a variety of consumer and industrial products in the form of silicone fluids and silicone polymers thereby playing an essential role in the country’s economy.
What is research telling us?
Much of the experimental works have shown that silicone is non-biodegradable due to its extreme physical properties. However, recent research has shown the biodegradability of emulsions of silicone polymers in soil in lab conditions as well in field soils. Most importantly, almost 50% silicone emulsion degraded within 4 to 9 weeks.
However, the products we use are not in emulsion form but a solid structure which is difficult to break. The study may encourage many more experiments to be done on silicone-based products and the finding of the experiments provide a better understanding of silicone for its long-term use in a positive way. This will also provide a step towards the replacement of plastic for a safe, healthy and pollution free environment.
Is there any alternative to silicone?
Silicone itself is a great alternative to single use plastics. However, because of its non-degradability, it is not the best eco-friendly material available. Other alternatives may have their pros and cons such as glasses. Even if glasses are recycled easily, they still have other limitations such as easily breakable, limited application and biodegradability.
Recycling of silicone
Unfortunately, the recyclability rate of silicone is very low. Most of it is usually melted down to an oil and end up in landfills or playground mulch. However, recycling silicone is not a complex process, and it can be recycled multiple times.
The processing of silicone is carried out in a specialized industry and most of the places are not equipped with that facility. Hence by the end of its life, silicone products are dumped with regular wastes by the users.
In this review, we could find the answer for the question “is silicone biodegradable?” with much emphasis on its efficiency compared to plastic products. We highlighted the importance of using silicone for a healthy and better environment (if not the best!) and how research and scientific study provide a solution for its biodegradation in future.
Frequently asked questions (FAQs): Is silicone biodegradable?
Does silicone damage the environment?
The damage caused by silicone is much less compared to that caused by plastics. First, it does not leach out any chemicals that can affect the living being. Secondly, it is highly durable and resistant to heat and cold thus making it more reusable with proper sterilization so that we do not have to dump the material after each use.
How long does it take for silicone to decompose?
There is no single answer to this question. With strong chemical treatments they are broken down faster. However, by natural process it may take 50 to 500 years based on the specific environmental conditions.
Can silicone be composted?
Due to silicone’s superior physical property and high resistance, these materials are non-biodegradable and cannot be composted.
How do you recycle silicone?
Silicone is processed in a specialized recycling factory. Recycling of silicone involves grinding the silicone products to much finer particles which can then be mixed with other materials to make several different products. However, the recycling is always downscaling that means not all the material is completely recycled. This is because there is no proper channel to collect and recycle silicone and most users simply throw it away after its complete use.
Is silicone safer than plastic?
Silicone is much safer than plastic due to its reusability. Unlike plastic, they do not leach out any chemicals to their surroundings even at high temperatures. Moreover, silicone is durable and hence does not disintegrate to form any microbeads which prevents land and aquatic animals from ingesting it.
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