Properties of cork

The physical and chemical properties of cork are very unique. It is a pure natural polymer material composed of cork parenchyma cells. Under the microscope, every cubic centimeter of cork contains 40 million cells, and the cells are filled with air.

 

Observing the cross-section of cork cells through an electron microscope, it was found that cork parenchyma cells were hexagonal prisms arranged alternately. The cell wall has a cellulose skeleton covered with cork and cork wax.

 

There are plasmodesmata passing through between the cell walls, which are the passage of protoplasm. After the cell dies, the plasmodesmata is blocked by resin, and the air in the cell is sealed inside, forming a closed air sac. When subjected to external pressure, the cell shrinks and becomes smaller, and the air pressure inside the cell increases. High; when the external pressure is lost, the air pressure inside the cell will restore the cell to its original state, which is also the principle of soft wood.

 

Cork is known as "soft gold" in the international market. Its main physical properties are light weight, low density, compressibility, elasticity, airtight, impermeable, buoyancy, strong elasticity, flexibility, compression resistance, and impermeability. Strong, moisture-proof and anti-corrosion, extremely poor conductivity, sound insulation, strong insulation, friction resistance, non-flammable, can delay the spread of fire, will not cause allergic reactions and a series of excellent physical properties.

 

The chemical properties of cork are very stable, will not breed various insects, and have no chemical reaction with weak acids, weak bases and other polar substances.

 

 

With the rapid expansion of the earth’s population, the sharp decline of natural resources such as forests, and the abnormal global climate change, our earth is facing unprecedented pressure. Faced with increasingly depleted forest resources, protecting forest resources has become a top priority. Cork resources are becoming more and more popular with people due to their sustainable regeneration characteristics. Cork products subvert the concept of tree felling for the manufacture of wooden products, and are based on natural cork oak trees without cutting trees. The oak tree can only be peeled when it grows from a small tree to 25 years, and then peeled once every 9-12 years. After the bark is peeled, it will not die and will promote the metabolism of the tree. So cork is a pure natural renewable resource.

 

Oak tree is a high-quality ecological raw material that can absorb carbon dioxide, improve the atmospheric environment, protect biodiversity and prevent desertification. Due to the influence of air pollution and other harmful substances, global warming is showing an irreversible trend. However, a recent foreign survey shows that Portugal’s cork forests can absorb approximately 4.8 million tons of carbon dioxide each year. The area of ​​cork forests in China is more than ten times that of Portugal.

 

At the same time, the cork is reusable and recyclable. The Americans2 once recycled cork on "Earth Day" and made them into stylish slippers for people to use. Cork's renewable, biodegradable, and recyclable characteristics conform to the connotation of Earth Day and better interpret the green concept. Cork, which is known for its environmental protection and low carbon, abides by the principle of harmony between nature and mankind, and realizes the strategy of sustainable development.