Latex (rubber)
From Wikipedia, the free encyclopedia
Latex, as found in nature, is the milky sap of many plants that coagulates on exposure to air. It is a complex emulsion in which proteins, alkaloids, starches, sugars, oils, tannins, resins and gums are found. In most plants, latex is white, but some have yellow, orange, or scarlet latex.
The word also refers to the thin stretchy material obtained by processing the sap (see Latex clothing, below). It can also be made synthetically by polymerizing a monomer that has been emulsified with surfactants.
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The cells or vessels in which latex is found make up the laticiferous system, which forms in two very different ways. In many plants, the laticiferous system is formed from rows of cells laid down in the meristem of the stem or root. The cell walls between these cells are dissolved so that continuous tubes, called latex vessels, are formed. This method of formation is found in the poppy family, in the rubber tree, and in the Cichorieae, a section of the Family Asteraceae distinguished by the presence of latex in its members. Dandelion, lettuce, hawkweed and salsify are members of the Cichorieae.
In the milkweed and spurge families, on the other hand, the laticiferous system is formed quite differently. Early in the development of the seedling latex cells differentiate, and as the plant grows these latex cells grow into a branching system extending throughout the plant. In the mature plant, the entire laticiferous system is descended from a single cell or group of cells present in the embryo.
The laticiferous system is present in all parts of the mature plant, including roots, stems, leaves, and sometimes the fruits. It is particularly noticeable in the cortical tissues.
[edit] Function and usage
Many plant functions have been attributed to latex. Some regard it as a form of stored food, while others consider it an excretory product in which waste products of the plant are deposited. Still others believe it functions to protect the plant in case of injuries; drying to form a protective layer that prevents the entry of fungi and bacteria. Similarly, it may provide some protection against browsing animals, since in some plants latex is very bitter or even poisonous. It may be that latex fulfills all of these functions to varying degrees in the numerous plant species in which it occurs.
Latex has many uses, from clothing to paint, but its first and foremost is rubber. Chicle, widely used as a base for chewing gum, is another latex product. Latex paint uses synthetic latex as a binder, which is not flammable, has little odor, and cures to form a dry paint film. Natural latex, which is nearly chemical free, is used in the manufacturing of natural Latex Mattresses, beauty application pads, and cushioning. It is a notably supperior product to polyurethane alternatives proven by its fifteen plus year life span and comfort. Its considered the cadillac of cushioning foams. Finally, poppy latex is a source of opium and its many derivatives.
Natural latex will decompose when exposed to the elements rapidly turning to dust.
Some people have a serious latex allergy, and exposure to latex or rubber products such as rubber gloves can cause anaphylactic shock. As latex has a protein found also in bananas, care should be taken to ensure people are not allergic to both. Guayule latex is hypoallergenic and is being researched as a substitute to the allergy inducing Hevea latexes.
[edit] Latex clothing
Latex is used in many types of clothing. It is different from rubber in that it is less refined and often thinner. Worn on the body (or applied directly by painting) it tends to be skin-tight, producing a "second skin" effect. It has a shinier finish than rubber.
[edit] Allergic reactions
Latex can cause an allergic reaction:
Irritant contact dermatitis
Allergic contact dermatitis
Latex Hypersensitivity
[edit] External links
[edit] See Also
- LaTeX A typesetting system
