What is the difference between natural latex and artificial latex?

Source of natural latex

Natural latex is harvested from the latex vessels found between the cork bark and the phloem of the rubber tree (Hevea brasiliensis). These latex vessels form a network-like structure. To extract the latex, a careful incision is made in the tree's bark, which allows the latex to flow out gradually until the flow diminishes and eventually stops.

Composition of natural latex

When freshly harvested, natural latex appears as a milky white or light yellow liquid, rich in small spheres made up of rubber hydrocarbons, proteins, and acetone extracts.

Natural latex also contains ash and water. Typically, the protein content in latex ranges from 2% to 2.5%. This complex colloidal substance consists of macromolecular organic compounds and provides stability by preventing oxidation of the rubber spheres.

The acetone extract content, usually around 2%, significantly contributes to the stability of latex. Water, which constitutes about 55% of latex, serves as a dispersing medium for minerals and other particles present and is often utilized as a foaming agent during product creation.

Ash content is often about 0.5%, with water-soluble substances mainly comprising various sugars, which can range from 1.5% to 4.2%. These proportions can impact the insulating properties of the final product.

Additionally, natural latex contains a small amount of antioxidants and enzymes; the former helps preserve raw rubber, while the latter can ferment the latex, effectively lowering its pH and promoting natural coagulation.

Uses of natural latex

Natural latex can be transformed into various products, including mattress components and numerous film products such as gloves and balloons.

Composition of synthetic latex

Synthetic latex is primarily made from a combination of artificial and natural latex, categorized by their respective proportions. Although chloroprene latex was one of the earlier types produced, it has since become less common, with styrene-butadiene latex emerging as the dominant option.

Styrene-butadiene rubber, also known as polystyrene butadiene copolymer, abbreviated as SBR, is derived from petroleum.

Uses of synthetic latex

Synthetic latex is commonly utilized in producing tire treads, conveyor belts, hoses, molded and extruded goods, and road paving asphalt, among other applications.

Production method of synthetic latex

The production of synthetic latex occurs through emulsion polymerization, utilizing butadiene and styrene as primary monomers along with additional chemical materials. The process starts with creating a styrene-butadiene slurry, from which unreacted monomers are subsequently removed, leading to the formation of the final rubber product through coagulation and drying.

Performance comparison of natural and synthetic latex

When comparing the performance of SBR latex, natural latex, and various sponge rubbers infused with different fillers, some differences can be observed:

1. Synthetic latex products generally have lower breaking strength and elongation compared to natural latex.

2. The compression deformation of synthetic latex remains consistently lower than that of natural latex, irrespective of the degree of compression applied.

3. The elasticity exhibited by synthetic latex is also less than that found in natural latex.

In conclusion, synthetic latex products typically exhibit inferior performance characteristics compared to their natural latex counterparts.