The differences between "latex" and "natural rubber"

03/20/2012


The Hygenic Corporation is one of the only manufacturers of both “natural rubber latex” and “natural rubber” products.  Many people don’t realize that there is a difference between “latex”, “natural rubber latex” and “natural rubber”.

It is interesting to note that the word “rubber” was believed to be given to this material back in the 17th century by Joseph Priestley.  Because it was commonly used as an eraser, or to “rub out” pencil marks, Joseph Priestley began calling it “rubber”.  The first rubber factory in the world was established near Paris in 1803 and there was one built in England in 1820.  In 1835 an American, Edwin Chafee, patented a mixing mill and a calender for processing rubber materials.  In 1839 Charles Goodyear (right here in Akron, OH where Hygenic is located!) discovered vulcanization which revolutionized the rubber industry.

Latex

The term “latex” basically describes any polymer in a water-based liquid or viscous state.  For instance latex paint does not contain natural rubber latex but does contain liquid synthetic polymers.  The word latex by itself does not refer to natural rubber latex.

Natural Rubber Latex 

Natural Rubber Latex refers to the white sap that comes from the hevea brasiliensis tree.  This sap can be further refined and compounded to render it more readily processed and to optimize physical properties. The Hygenic Corporation has two manufacturing processes that allow us to manufacture natural rubber latex tubingsheeting and film.  Products manufactured from natural rubber latex tend to be very pure and have the enhanced physical properties that natural rubber latex are known for – outstanding elongation, tear properties and recovery.

Natural Rubber 

As the name suggests, dry natural rubber is natural rubber latex that has been dried into bales that can be more easily transported and stored.  The dry natural rubber can then be compounded with various processing aids and curatives made into products using more common manufacturing methods such as extrusion, calendaring and molding.  The typical physical properties of natural rubber products are very similar to those of natural rubber latex, but are not exact due to differences in the compounding and processing cycles.  The Hygenic Corporation is one of the few manufacturers who can extrude natural rubber into tubing and custom profiles.  The extrusion process can generally control dimensions more accurately than a process using liquid natural rubber latex which means we can often hold tighter tolerances on our extruded natural rubber tubing and profiles.