What is guayule?
Guayule (why-you-lee) is a desert plant indigenous to the southwest United States and northern Mexico. The species (Parthenium argentatum) is a new industrial crop and the only species other than Hevea (the Brazilian rubber tree, Hevea brasiliensis) that has been used for latex production on a commercial scale.
Why is the technology associated with the manufacturing of guayule unique?
Guayule is the only source of natural rubber latex free of tropical proteins. Yulex® natural rubber meets the critical performance standards necessary for many medical, industrial, and military applications and exceeds performance of many synthetic lattices.
The guayule processing technology includes methods for latex extraction and product refinement. Former USDA scientist and now an executive of Yulex, Dr. Katrina Cornish developed proprietary methods of extracting this latex and assuring extremely low protein concentrations. In addition, proprietary commercial farming, harvesting and biotech programs have been developed that increase the plant's latex yields with faster growing cycles to produce more product for the medical, building, and energy industries.
How is guayule latex harvested and manufactured compared to that of tropical latex?
The technology involves homogenizing the entire hedged guayule plant. Rubber is found primarily in the bark and must be released in the processing. Branches are ground into a kind of "guayule milkshake" by gently breaking open the cells in the plant, releasing intact rubber particles and creating an aqueous suspension. The suspension is then placed in a centrifuge for separation. Since the guayule rubber particles are lighter than the aqueous solution, they are separated from the suspension. The rubber portion of the mixture is culled off the top (much the same way that cream is skimmed off milk) and purified into latex.
Traditional latex is tapped from ducts, which are found in a layer immediately outside the cambium of the Hevea tree. The tapper shaves off a portion of the intact section of the bark and then cuts into this layer making certain not to damage the cambium, since that is where the growth of the tree takes place. The latex then flows and is captured in a cup placed below the cut.
Why is guayule latex preferred for the manufacturing of safe natural rubber latex products?
Guayule is free from the tropical allergenic proteins contained in tropical, or Hevea, latex and contains less than 2% of its overall protein content. Further, guayule latex proteins are different than those in Hevea latex and their non-cross reactivity has been well documented. Clinical data suggests guayule latex contains no "super sensitizing" proteins like those in Hevea, or peanuts for example. Therefore, products made from guayule latex will not trigger latex allergy symptoms in sensitized individuals.
Equally important, Yulex® natural rubber, derived from guayule, also meets the category's high performance standards based on its natural elasticity, tensile strength, barrier protection, durability, and elongation characteristics.
