For the most part, we as consumers don’t have the option of seeing just how the products we purchase are made. Oftentimes we simply purchase a finished product without considering just went into producing it. Truth be told, having knowledge of how something is made can definitely aid us when it comes to deciding which products are the best for our needs, that way we can be sure of the materials that went into it and the quality of the product upon its completion. If nothing else, it is a smart shopping decision, as well as an opportunity to enrich our minds with knowledge. The same is true for natural rubber sheeting and the many rubber products that are out in the market, making it important to know just how is natural rubber made. Natural rubber, also known as pure gum, comes from a number of different sources; the steps involved in processing rubber are essentially the same across the board, however. So, if you wanted to acquire a gum rubber sheet, there are many natural rubber sheet suppliers out there who will all be able to offer a product that is suitable to your needs. Here is a simplified explanation of the steps involved in processing rubber:
Pure Gum Rubber – Commercial Grade – 40A
- Tapping the Tree: It all starts with the tree. The Hevea brasiliensis, native to South America and seen on plantations in Southeast Asia, in countries such as Thailand, Malaysia, and Indonesia. The tree is cut at an angle, and as a part of the tree’s natural healing process, it secretes a latex material which is subsequently collected in buckets or coconut shells. This is called “tapping” the tree.
- Collection: Collection of the latex is done about every two or three days, and once that area of the tree has been fully tapped, a new area on the tree can be cut open. It takes about seven years for a particular area on the tree to be healed for reuse. Roughly a cups-worth of latex will be collected after about three hours, at which point a new collection point will be made on the tree.
- Keeping it as a Liquid: The latex material needs to remain as a liquid. If left on its own for too long, exposed to the air, it will solidify. If this happens, the hardened material, as well as the strip of latex that is solidified along the wound on the tree will be sent to processing plants, as they can no longer be treated on the plantations. Substances such as ammonia are added to the latex to allow it to maintain its liquid form.
- Starting the Mix: After the latex has been collected, it will be mixed with diluted acid and other coagulants. The process by which the latex and other substances are mixed is called an emulsion.
- Dispersion: Particles are dispersed into the mixture to create a substance which is of a homogenous state. Common dispersing agents are gelatin, casein, glues, and detergents. It is at this time that other things are added such as pigments to add color, fillers, and vulcanizing agents.
- Charge!: An electrical charge is released over the substance to further prevent solidification.
- Inspection: The mixture is rolled twice. The first time is to remove excess water; the second time is to texture the rubber and turned into a gum rubber sheet. After the pure gum is rolled, it is then hung up to dry and inspected visually. They are tested technically on larger plantations.
- Vulcanization: The rubber may or may not be vulcanized. Vulcanization involves heating the rubber with sulfur to create sulfide crosslinks between the monomers of isoprene which form the polymer of rubber. This process strengthens the product and makes it suitable for industrial and commercial use. Natural rubber sheeting is one such by-product!
- Removing Imperfections: After inspection, any imperfections that are found by the natural rubber sheet suppliers are removed. The sheets are then baled together and with talc to separate them and keep them from sticking to each other. Block rubber undergoes a similar process, but is chopped up and pressed into bales.
- Product Forming: Sometimes, the liquid latex, whether or not it has been vulcanized, will be not be made into natural rubber sheeting, but instead poured into heated molds designed for a particular use. At this point, other substances can be added, such as carbon black for tires. Latex gloves are produced this way.
How is natural rubber made? These are ten easy steps that tell you just how pure gum is produced and perhaps even turned into a pure gum rubber sheet. Now, when you contact any of the various natural rubber sheet suppliers, you will already be familiar with the processes involved in creating the product! They will be impressed by your knowledge and know that they are dealing with a serious customer who can’t be fooled!
SBR Rubber – Black – 70A – 3/8″ x 36″
Pure Gum Rubber – Commercial Grade – 40A
- Has a very high tensile strength
- Can resist most organic salts, ammonia, acids, and alkalis
- Able to operate in temperatures between -20° F and 170° F
- Pure gum rubber can be used for some medical applications
- Not recommended for use with strong caustic oils and chemicals
- Ideal for industrial applications that need good “bounce-back” characteristics from rubber parts
Soft and Elastic: Pure gum rubber is valued for being a softer, more elastic type of rubber. It has a low durometer rating of 35-45, meaning that while it is not a very hard material, it is very elastic. This high elasticity gives it a level of adaptability for various seal and gasket applications that is hard to beat. This flexible rubber material can be stretched further than other elastomers. It is the prime reason why natural gum rubber is used as squeegee blades, industrial skirting, and drum practice pads.
Non-Marking Rubber: A very useful characteristic of pure gum rubber is that it is non-marking. No matter what type of color variation it comes in, brown to light tan, a natural rubber product will not leave any stains or marks on the places where they are used. This feature is especially useful in applications like window cleaning.
