What are the types and uses of latex？
Everyone knows condom, Do you know what it is made of?
Latex is the general name of polymer latex dispersed in water. Usually, the water dispersion system of rubber particles is called latex, and the water dispersion system of resin particles is called emulsion. It can be directly used as surface coating, film and adhesive. After processing, it can be made into raw rubber and latex products (such as sponge, glove, balloon, condom, medical hose, etc.), which are widely used in daily life.
Latex can be divided into natural latex, synthetic latex and artificial latex.
1、 Natural rubber latex
The latex was milky white, the solid content was 30% - 40%, and the average particle size was 1.06 μ M. The fresh natural rubber latex contains 27% - 41.3% rubber, 44% - 70% water, 0.2% - 4.5% protein, 2% - 5% natural resin, 0.36% - 4.2% sugar and 0.4% ash. In order to prevent natural rubber latex from coagulating due to microorganism and enzyme, ammonia and other stabilizers are often added. In order to facilitate transportation and processing, natural rubber latex is concentrated to more than 60% solid content by centrifugation or evaporation. Natural rubber latex is mainly used in sponge products, extruded products and impregnated products.
2、 Synthetic latex
Generally, latex of 20% to 30% solid content can be prepared by emulsion polymerization, such as polybutadiene latex, styrene butadiene latex, etc. In order to make the solid content reach 40% ～ 70%, the rubber particles are agglomerated into larger particles, that is to say, the measures of adjusting polymerization formula, adding agglomerating agent, stirring, pressurizing and freezing are mainly adopted in industry, and then the concentration method similar to natural rubber latex is adopted. Synthetic latex is mainly used in carpet, papermaking, textile, printing, coating and adhesive industries.
3、 Artificial latex
Non latex polymerized rubber latex. Water and surfactant were added to the solution (such as isoprene rubber) to disperse the rubber particles in water, and then the solvent was evaporated. If the rubber cannot be fully dissolved in the solvent, the raw rubber or rubber compound can be kneaded continuously in the presence of water phase containing emulsifier until a stable rubber water dispersion is formed. The use of artificial latex is similar to that of synthetic latex.
Take latex gloves and condoms for example, reflecting the close relationship between latex and human life.