The rubber industry has evolved extensively over the years since its inception, with a huge explosion of the industry around the time of World War II, when natural rubber plantations in Southeast Asian were being occupied, and those who fought on the side of the Allies lost all access to these resources. That being the case, scientists from all the warring countries sought out the ways in which they could produce an artificial form of rubber, so that their nations could continue to produce general rubber products, especially the tires that were needed desperately for the thousands of warfare vehicles being produced at the time. Rubber suppliers have tried to master nature by producing rubber from trees and petroleum. In fact, the majority of elastomers that are produced today are synthetic. Seeing as rubber is such an integral part of our lives, it would be beneficial to know just how is rubber manufactured, especially when looking in to the elastomer-based products that you want to bring in to your home or place of business. Rubber wholesale use is in complete motion. It is used on the vehicles that transport us in the form of tires, gaskets and hoses. It is in the clothes we wear, like rain boots, belts, wet suits, sports shoes, or fishing waders. It is on the floors that protect us such as, doormats, nonslip mats, playground surfacing, and gym flooring. It is on the bottom of your chair, the feet that protect your laptop, and yes it may comprise the roof on the top of your building! We may forget about rubber and our need for it, but one look around will remind you of our economic need for the product.
While the demand for natural rubber is no longer what it used to be, with synthetic elastomers dominating the markets, it is still important to know how rubber suppliers are producing it. The latex that is used to form natural rubber is taken from the tree Hevea brasiliensis that can be found in plantations in Southern America and Southeast Asia. After the latex has been collected, compounds are added to it through emulsions or dispersions. An emulsion is the mixture of two or more liquids that would normally have been unmixable. Dispersion involves dispersing particles to create a material that is of a homogenous state. Some common dispersing agents are gelatin, casein, glues, and soaps (detergents). Other substances such as softeners, fillers (for added strength), pigments, antioxidants, and vulcanizing agents are added as well. The latex compound is stabilized with surface-active agents which will prevent the coagulation (semi-solidification) of the particles by releasing an electrical charge over the surface of the rubber particles, which prevents the mixing. After this, the compounded latex materials are ready to be dipped, molded, foamed, or spread in order to create general rubber products. Natural rubber wholesale has an international market and is traded in all major commodity exchanges. Do not forget about rubber’s commodification in either form discussed here. Whether it is from tree sap or black gold, either way it is derived from a commodity.
Rubber, by and large, is produced synthetically because it is needed in far greater quantities. Deeply involved in the process of creating an artificial elastomer is polymerization, the process by which small molecules (called monomers or units) are combined chemically to produce long chain-like strands of the same molecules, called a polymer. The individual units may be different molecules repeated in a pattern, or simply one type of molecule repeated over and over again. In order to produce a polymer which exhibits its own unique physical properties, a minimum of 100 monomers is necessary. The polymerization of molecules for synthesizing rubber is done in one of two ways:
Emulsion Polymerization: The polymerization reactions take place within a hydrocarbon solvent. This form of polymerization is best used for polymers that are used commercially in a solution form, such as adhesives or coatings. The polymers that are produced with this method are greater in length and flow more easily.
Solution Polymerization: This process involves the formation of a stable emulsion of latex in water using soap or a detergent. Initiators are dissolved into the substance to begin polymerization, and the process is stopped with chemical inhibitors. The substance is coagulated with acified brine, washed, dried, and pressed. This method is complex in comparison, and produces polymers with very high molecular weights.
Both of these processes involve the use of additives to obtain the desired physical properties of natural rubber, and sometimes, these properties are even optimized for the use of general rubber products. That being the case, petroleum-based rubber products can oftentimes be preferred over products made from natural rubber, by rubber suppliers, because they are likely to demonstrate all the consistent qualities and are more readily available. Rubber wholesale prices may also experience more fluctuation in both NR and oil-based versions and this may have an effect on rubber suppliers’ decision to choose one or the other variation. It is important to know just how is rubber manufactured when determining what qualities you want your products to have, so that you can find the kind of rubber that is tailored to your specific needs. And for those of you that are sifting through materials for the sake of knowledge, do not forget about rubber’s constant presence in our lives!