Years ago, when we were looking for baby toys made of natural materials, we came across latex – natural rubber. However, we knew very little about it – only that car wheels are made of rubber. We started searching and quickly learned that latex is harvested mainly from trees called HEVEA BRASILIENSIS.
What is LATEX?
Latex is a milky liquid in the latex vessel or in the cells of a plant. Only around 13 % of plants producing latex also contain rubber! The HEVEA BRASILIENSIS tree is the most popular source for harvesting latex due to the fact that it only needs a slight incision into the trunk and the latex is flowing. Skilled rubber tappers collect the latex from each tapped tree.
Source Online: Arias M and van Dijk P (2019): What Is Natural Rubber and Why Are We Searching for New Sources?
What needs to be done so that latex can be used?
There are two options: After harvesting, latex can be sold either as a liquid or a solid material. If it is to remain liquid, it must be thickened and stabilized with the addition of ammoniac. For a solid material, latex must be coagulated with sodium sulfite or a weak formic or acetic acid. After that, the material must be rolled.
On YouTube we found an informative video from Discover Agriculture that shows the entire process from harvesting rubber milk to making sheets on a small-scale farm in Sri Lanka: