Natural rubber latexThe rubber tapped from the rubber tree (see natural rubber) is milky white, with a solid content of...
Natural rubber latex
The rubber tapped from the rubber tree (see natural rubber) is milky white, with a solid content of 30% to 40%, and the average rubber particle size is 1.06μm. Fresh natural rubber latex contains 27%～41.3% (mass) of rubber component, 44%～70% water, 0.2%～4.5% protein, 2%～5% natural resin, 0.36%～4.2% sugar, 0.4% ash . To prevent natural rubber latex from coagulating due to the action of microorganisms and enzymes, ammonia and other stabilizers are often added. In order to facilitate transportation and processing, natural rubber latex is concentrated to a solid content of more than 60% by centrifugation or evaporation, which is called concentrated latex. Natural rubber latex is mainly used for sponge products, extruded products and impregnated products.
Generally, synthetic latex (such as polybutadiene latex, styrene-butadiene latex, etc.) with a solid content of 20% to 30% can be prepared by emulsion polymerization. In order to achieve a solid content of 40% to 70%, the rubber particles are firstly agglomerated into larger particles. That is, in the industry, measures such as adjusting the polymerization formula, adding agglomerating agents, stirring, pressurizing, and freezing are mainly used, and then Natural rubber latex is concentrated in a similar way. Synthetic latex is mainly used in industrial sectors such as carpets, papermaking, textiles, printing, coatings and adhesives.
Non-emulsion polymerized rubber latex. It is made by adding water and surfactant to the glue liquid produced by solution polymerization (such as isoprene rubber), dispersing rubber particles in water, and then evaporating the solvent. If the rubber cannot be fully dissolved in the solvent, the raw rubber or rubber compound can be continuously kneaded in the presence of an emulsifier-containing water phase until a stable rubber water dispersion is formed. The use of artificial latex is similar to that of synthetic latex.