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Cork is a natural material known since ancient times (Phoenicians and Greeks), mainly as a buoyancy aid and as a sealant for bottles and jars. However, it was not until the late 19th century that people began to understand some of the many other attributes of this unique material.

One cork product, expanded cork agglomerate, was discovered by accident by American life jacket manufacturer John Smith of New York, who patented the product in July 1891.

At that time, life jackets were made using canvas vests filled with cork pellets in tubes or metal cylinders that held the canvas in tension until the filling was complete. One night, the bottle filled with pellets was accidentally thrown into a hot cauldron.

The next day, while cleaning the kiln, it was discovered that the heat had not absorbed the cork inside the pipe, but had rather turned the pellets into a perfectly aggregated dark brown cylindrical mass. The heat in the kiln expanded the pellets, which compressed and became a solid block formed by the natural resin in the cork.

Today, expanded cork agglomerate, commonly known as insulating cork board (ICB), is produced by exposing cork pellets (without any additives) simultaneously to a temperature of 335 ° C and a pressure of 0.5 kg/cm2 for 20 minutes.

In this process, the cork pellets expand (i.e. the empty spaces between the individual pellets are closed by the natural binder (suberin) of the wood material, which is released in the process) and form agglomerate blocks.

The material is odourless and resistant to insects and rodents. Expanded cork does not age, which means that it maintains its properties while maintaining dimensional stability over the years.

Since each cubic centimetre of cork contains around 40 million cells filled with microscopic amounts of air containing nitrogen and oxygen, it was realised that cork can also act as an insulator against temperature and sound.

For this reason, the construction industry is currently using more and more cork, as architects strive to make buildings more energy efficient and use environmentally friendly materials for sound insulation and damping.

Cork reduces the spread of surface and impact sounds. In the event of a fire, expanded cork does not release any toxic gases. The material is completely recyclable and can be reused in construction. It is currently used worldwide in construction due to its thermal, acoustic and anti-vibration properties, as well as its resistance to fire.

This super material is also increasingly appreciated for its many other advantages: in addition to being a natural, biodegradable and renewable material, it is also a CO₂ absorber, playing a key role in protecting the environment.

Designer Rosa de Jong creates micro-homes made of cork that are built on the sides of small cliffs. Her miniature environments are covered with artificial moss and decorated with model trees, which add charm to the tiny homes. Previously, she hung her works in glass tubes, which created the illusion that the works were floating in the air.

Her latest works hang between two panes of glass and are secured with thin wires. De Jong worked with her father to create wooden frames for the structures, which include small wheels that allow the owner to adjust the position of the floating islands. Two of her new works, Remembered and Imagined , are being shown simultaneously in a dual-city exhibition that opened on August 24, 2018 at Paradigm Gallery in Philadelphia and on August 30, 2018 at Antler Gallery in Portland, Oregon. You can see more of the Amsterdam-based designer’s miniature homes on Instagram and on her website Micro Matter .

In her Micro Matter project, de Jong also hand-crafted miniature environments placed in glass test tubes, creating the illusion that the objects are floating in mid-air, reminiscent of the flying castle in Studio Ghibli’s Howl’s Moving Castle.

De Jong hand-builds her tiny buildings, each one looking like a pastoral home built on tiny cliffs. Miniature staircases curve through hand-painted cork, and her latest works hang between glass panes and are secured with wires. Her work is currently on display at Antler Gallery in Portland, Oregon, through August 30.

Encased in long, vertical glass blocks, the miniature landscapes create small scenes for the viewer to explore and imagine. Handcrafted from an eclectic mix of materials, including paper, cardboard, tree branches, and moss, the small scenarios present surreal architectural environments and structural impossibilities. A stack of buildings teeters on the edge of a small mound of earth that seems to float in midair; an urban structure sits in a transparent tube; a miniature paper water tower rises above a suspended patch of greenery. Take a look at the series of small worlds titled “micromatter” below, and see more about de Jong’s intricate process here .

Portuguese company Amorim Cork Composites offers new cork solutions to protect electric vehicle batteries. The unique properties of cork, such as low density, reduced thermal conductivity and resistance to high temperatures, make it an ideal material for developing EV battery components. Additionally, cork’s cushioning and sealing properties make it suitable for a variety of applications both inside and outside the battery.

Amorim Cork Composites has used its expertise in developing high-performance materials for sectors such as seals and aerospace to create a range of solutions specifically for the electric mobility sector. These solutions focus on seals, housings and cell spacers to prevent thermal runaway during thermal events.

A solution combining cork with silicone has been developed for battery sealing. This solution meets UL-94 V0 flammability requirements and has a compression set of less than 40% at 50% deflection. It also provides resistance to wear, UV radiation and ozone. By combining cork, a 100% natural, reusable and recyclable material, with other materials, Amorim Cork Composites creates products that provide excellent performance while being environmentally friendly.

For the interior of the batteries, multi-layer systems have been developed using cork combined with materials such as mica, basalt/carbon fibers and others. These systems act as thermal barriers between cells or modules (cell spacers/thermal pads) and provide protection to the battery casing.

It may seem unlikely that you will find a material with multiple applications in cutting-edge electric vehicle drive systems that literally grows on trees, but that is exactly what Amorim Cork Composites offers.

The multi-layer systems are available in thicknesses from 0.8 to 30mm and in a wide range of formats, allowing the creation of products with a compressibility of up to 80% at 2.5Mpa, thermal insulation of 20-30°C/min and density of 200kg/m3, while guaranteeing a long-lasting solution thanks to the high cork content.

With the new range of Amorim Cork Composites solutions, we offer technical, efficient and sustainable alternatives that help guarantee the performance and durability of batteries, without forgetting the main objective underlying the electric revolution – sustainability.

Rolls Royce chooses cork solutions for the world’s first all-electric aircraft. In the “Spirit of Innovation,” the world’s fastest all-electric aircraft, cork agglomerates were used in the insulation shell of the battery box. The cork solution was chosen because of the need to find a material for the battery housing that was not only structurally sound, but also lightweight and extremely fire-resistant.

Portuguese company Amorim Cork Composites offers cork as a versatile material for cutting-edge electric vehicle drive systems. The raw material, the bark of the cork oak (Quercus suber), is widely used in various industries, such as aerospace, defense, energy and automotive. Cork is currently used for thermal protection, vibration dampening and shock absorption in battery packs of electric vehicles. According to Thomas Peroutka, Mobility Manager at Amorim, cork was used in early cars by Gottlieb Daimler and Carl Benz for sealing. Additionally, since the beginning of space exploration, cork has been used in thermal protection of rockets and satellites. Its shock-absorbing properties were beneficial in armouring applications, while its vibration-dampening and acoustic properties were used in electrical transformers.

Cork has a beehive-like microstructure, consisting of cells in the shape of tiny, gas-filled pentagonal and hexagonal prisms. There are about 40 million cells per cubic centimeter of cork. Amorim characterizes this structure as a cluster of microballoons or micro-cushions that gently press against each other, creating a characteristic blend of elasticity and compressibility that are fundamental to its dampening and shock-absorbing properties.

Moreover, cork is impermeable to gases and liquids, resistant to high temperatures, fire and friction, while being strong and lightweight.

In terms of chemical composition, 45% consists of the complex biopolyester suberin, with smaller proportions of lignin (27%), cellulose, waxes and other polysaccharides (12%), tannins (6%) and ceroids (6%).

Initially, Amorim focused on developing thermal protection pads for battery interiors, anti-vibration pads and structural elements. In structural applications, cork is combined with carbon fibers, glass fibers and/or metals such as aluminum to create housings and covers with internal thermal insulation, noise and vibration damping, impact protection, and structural integrity.

According to Peroutka, Amorim has developed a variety of materials and solutions in different formats for different applications in the e-mobility sector. The company is currently in talks with OEMs and Tier One suppliers about innovative ways to use the material.

One of these methods involves injection molding, where the cork must first be pelletized and combined with other materials. This approach allows for a wide range of process parameters, including extrusion, lamination, thermoforming and thermoforming.

Peroutka emphasizes that cork is not only carbon neutral, but actually carbon negative. Studies suggest that for every tonne of cork produced, a cork oak forest can absorb up to 73 tonnes of CO2.

Cork trees are not cut down to harvest the cork; instead, the bark is allowed to grow back for nine years before being harvested again. Each tree can be cut down around 17 times during its life, which is on average around 200 years.

What’s more, cork oak forests are key areas for biodiversity, have a protected status, help regulate the climate, promote sustainability and contribute significantly to the planet’s ecological balance.

Peroutka mentions that the first applications of the batteries, resulting from cooperation with three European companies, will be launched later this year. “We are currently conducting final tests and if everything goes according to plan, we will start the process of scaling up pre-series production.”

Cork has a long history. Below we present 6 interesting facts about cork that will allow us to learn more about cork, an environmentally friendly and innovative material.

The largest and oldest cork oak in the world is known as Assobiador (Whistler). The name was inspired by the sound of songbirds falling on tree branches. The cork oak, planted in 1783, is over 14 meters high and has a trunk circumference of 4.15 meters.

During the 2010 NATO summit, celebrities such as Barack Obama, Angela Merkel and Hillary Clinton received gifts in the form of cork fashion and accessories. The US president also received a collar for his Portuguese water dog, Bo.

Hollywood uses cork to imitate the remains of explosions. Cork was used in the films “Ghostbusters” and “Mission Impossible”.

The Portuguese cork closes the most expensive whiskey in the world, Dalmore Trinitas 64, which costs 118,000 euros per bottle.

The floor of the Sagrada Familia cathedral in Barcelona was made of cork to improve acoustics and prevent hypothermia.

No trees are destroyed during the production of cork. After harvesting, the cork oak undergoes a self-regeneration process that cannot be observed in any other species.

Cork forests are not only the cultivation and harvesting of oak bark, but also a dynamically developing tourism industry. Tourists visit these areas not only in Portugal, but also in Italy, in Sardinia, an island also known for its natural corcan cultivation. There are special websites on the Internet that invite you to take long walks through the growing areas of this versatile raw material. Tourists are also seduced by the prospect of visiting numerous vineyards, medieval fortresses and abandoned chapels.

One of the places in Portugal where we can discover the natural heritage of this beautiful country is the Maroteira farm and its surroundings. Herdade da Maroteira is located on the slopes of the Serra d’Ossa in the Alentejo region of southern Portugal. This 330 hectare property has been owned by an Anglo-Portuguese family for 5 generations and was originally active in cork and cattle production until today.

There are currently vineyards on the property that produce internationally recognized wines. The wonderful location offers you the opportunity to undertake numerous activities that will bring you closer to nature. This is how we should live every day, resting in peace in harmony with the environment, learning from plants and animals, enjoying wine and meeting authentic country people – say the current owners of this beautiful farm.

Another form of entertainment for local visitors, who are increasingly looking for alternative ways to spend their holidays and leisure time, is trekking through the Alentejo forest and along country roads with views of the Sierra D’Ossa. Tour guides enthusiastically talk about the advantages of the corcan growing areas.

The residents also have an offer for fans of motorized rides. At https://corktrekking.com/ you can also book a jeep ride around the Herdade da Maroteira estate at affordable prices and experience the incredible rural atmosphere of the cork forests of the Alentejo region.

On the website https://www.visitcorkterritories.co.uk/ we also have the opportunity to take kayak tours in Spanish cork forests along the Rio Palmones. The site also offers the organization of walking and cycling tours in the local forests of the Gibraltar region.

We also have the opportunity to visit cities best known for cork harvesting and processing. These are mainly towns like Grandola, Vendas Novas and Vives. The first point mentioned is particularly noteworthy. The cork oak forest covers about 48% of the total area of the district, i.e. about 39,645 hectares. Thus, at the regional level (NUT II Alentejo), the municipality of Grândola represents 6.4%; nationally 5.4%; and around 1.8% of the total area of cork oaks worldwide. Experience shows that the cork produced in the cork oak forest of the Sierra de Grândola is often considered by various industry experts to be one of the best corks in Portugal and even the world.

In public transport, cork plays a key role as an insulating agent, reduces vehicle weight and contributes to reducing energy consumption. It also serves as decorative elements, e.g. in the case of cars or airplanes. It is even a key material when it comes to safety. This is the case with rockets and landers of space agencies such as NASA.

Porsche collaborated with designer and influencer Sean Wotherspoon to create a colorful car with the same theme. Based on the Porsche Taycan 4 Cross Turismo, the car takes inspiration from the Harlequin while taking the concept to the next level, even borrowing the interior theme.

As a vegetarian, Wotherspoon wanted to make sure the car’s interior was not covered in leather, so he used corduroy (a material already used in the 911 Targa Heritage Edition) and cork (a material obtained from the bark of the cork oak tree) for the headliner, seats and sun visors. visors, as well as on the dashboard, pillars, center console, steering wheel and floor mats.

Fiat Fiat 500 Spiaggina

Decorated in two shades of sky blue and pearl white, this Spiaggina is typically summery, with no roof like the original and no rear seats, as it now has a cork-adorned storage compartment and an integrated shower, presumably designed to remove sand after a day at the beach.

The model pays tribute to the world of sailing, such as a low windshield (almost non-existent) and a cork structure covering the rear with a pattern imitating teak-floored boats used on board, yachts.

Cork can be combined with various thermoplastic materials, partially replacing plastic and creating more sustainable end products.

These materials can be processed using various production techniques – such as extrusion, injection, thermoforming, blow molding or continuous pressing – to create components fully tailored to the customer’s technical requirements.

Cork polymer blends (CPC) can also be visually customized to suit the aesthetic needs of the final design.

The use of cork composites helps reduce weight and, as a result, reduce power costs. Additionally, thermal comfort and the lack of noise are important, which the cork also has a significant impact on. The railway industry is one of the segments of the economy where energy consumption is important in the context of economics and ecology.

The high stress parameters of cork composites developed in laboratories with the safety of railway passengers in mind are also important. It is also worth mentioning that the German company Siemens is the co-author of a solution that allowed the use of a light and flexible cork floor in the Warsaw metro.

The last but not least important parameter of the cork is fire safety. This last parameter was the main reason why NASA, for nearly half a century, has used a mixture of cork and other materials to protect the skins of its rockets, which must endure extreme temperatures as they pass through the atmosphere. In airplanes, cork is used to create finishes or, as in trains, to reduce the weight of the machine. In yachts, next to teak wood, it is the most popular solution.

A suitable cork composite is resistant to moisture and heating from the sun. The automotive industry is also a very popular place where cork is used. Brands such as BMW and Mercedes use cork finishing for car interiors, such as dashboards. Rubber cork and its use in the form of car seals as a more ecological alternative to rubber are also popular.

Greenwashing is “the act of misleading consumers about a company’s environmental practices or the environmental benefits of a product or service.” However, it may also be carried out, intentionally or unintentionally, by governments or other entities that make misleading claims about the environmental performance or impact of their activities. Here are 3 selected examples of greenwashing.

1) Hidden compromise

This example focuses on one narrow pro-environment feature, neglecting to pay attention to more important and broader environmental issues. Examples include technology that promotes energy efficiency without disclosing hazardous materials used in production.

Why doesn’t this apply to natural cork?

In the case of, for example, expanded cork, it is made of cork granulate heated to high temperatures in special vats. In these vats, a natural granule-binding ingredient – suberin – is produced, thanks to which it is possible to obtain cork slabs without any chemicals.

2) Unclear wording

This issue concerns claims that are very broad and unclear, which may consequently be misunderstood by consumers. An example would be using the word “natural” to claim the environmental benefits of a product or service. For example, both arsenic and uranium are “natural” ingredients, but they are also poisonous.

Natural cork has a globally recognized FSC certificate.

The acronym FSC itself stands for Forest Stewardship Council, i.e. Council for Responsible Forest Management. It is an international not-for-profit organization and a member of ISEAL – a global association of social and environmental standards systems. The certificate, based on the Principles, Criteria and Indicators of Good Forest Stewardship, is issued by the above-mentioned FSC Council.

What are the Principles, Criteria and Indicators of Good Forest Stewardship?

This is a document of standards, developed in 1994, based on the knowledge and experience of ecologists and generations of foresters – both theoreticians and practitioners. When developing the document, the FSC Council, in addition to these elements, also took into account the achievements of modern education and the functioning of forest management.

Cork oak bark has many uses in gardens, zoos and animal terrariums.

Here are some ways you can use it:

1. Garden pots: Bark from the cork oak can be used to make garden pots. Its natural insulating properties will help protect plant roots from extreme temperatures. In addition, cork bark is lightweight, durable and weather-resistant, which makes it an excellent material for outdoor planters.

2. Pavement in zoos: In zoos, cork oak bark can be used as a natural paving in animal enclosures. Its soft and flexible structure provides comfortable conditions for animals and helps to maintain proper soil moisture.
3. Zoo decorations: Cork bark can also be used to create decorations in zoos. It can be used as a decorative element around catwalks, on walking paths or around observation decks. The cork bark adds a natural charm and is safe for pets.