Latex is a stable dispersion (emulsion) of polymer microparticles in aqueous media. It is found in nature, but synthetic latex can be prepared by polymerizing monomers such as emulsified emulsified with surfactants.
Latex as found in nature is a liquid like milk found in 10% of all flowering plants (angiosperms). It is a complex emulsion composed of proteins, alkaloids, starches, sugars, oils, tannins, resins, and gums that condense on exposure to air. Usually radiates after tissue injury. In most plants, the latex is white, but some have yellow, orange, or red latex. Since the 17th century, latex has been used as a term for liquid substances in plants. It serves primarily as a defense against herbivorous insects. Latex does not become confused with plant sap; it is a separate substance, produced separately, and with separate functions.
The word latex is also used to refer to natural latex rubber, especially unvulcanized rubber. As in products such as latex gloves, latex condoms and latex clothing.
Initially, the name given to latex by indigenous equatorial tribes that cultivate plants is "caoutchouc", from the word "caa" (tears) and "ochu" (tree), because it is collected.
Video Latex
Biology
Laticifers articulation
The cells (laticifiers) in which the latex is found form a laticiferous system, which can form in two very different ways. In many plants, the laticifer system is made up of cell lines placed in the root or root meristem. The cell wall between these cells is dissolved so that a continuous tube, called latex vessels, is formed. Because these vessels are made of many cells, they are known as articulation laticifers . This forming method is found in poppy families and in rubber trees (Para rubber trees, members of the Euphorbiaceae family, members of the mulberry and fig family, such as the Panamaian rubber tree Castilla elastica ), and members of the Asteraceae family. For example, the Parthenium argentatum guayule plant, is present in the Heliantheae tribe; Other latex-bearing asteraceae with laticic articulation include members of Cichorieae, a clade whose members produce latex, some of which are commercially attractive. These include Taraxacum kok-saghyz , a species cultivated for latex production.
Non-articulated laticifers
In graft families and grass-producing families, on the other hand, the lactate system is very different. At the beginning of the development of seedlings, the latex cells differentiate, and when the plants grow these latex cells grow into a branching system that extends throughout the plant. In many euphorbs, the entire structure is made up of a single cell-type system known as non-articulated laticifer , to distinguish it from the multi-cellular structure discussed above. In adult plants, the entire laticifer system is derived from a single cell or group of cells present in the embryo.
The laticifer system is present in all parts of the adult plant, including roots, stems, leaves, and sometimes fruits. This is particularly noticeable in cortical tissue. Latex usually emits white fluid, but some cases can be seen clearly, yellow or red, as in Cannabaceae.
Maps Latex
Productive Species
Latex is produced by 20,000 species from more than 40 families that occur in several lineages in both dicoty and monocotyledonous plant species. It is also found in conifers and pteridophytes. Among tropical plant species 14% make latex, compared with 6% of temperate plant species. Some members of the mushroom kingdom also produce latex because of injury, such as Lactarius deliciosus and other milk caps. This shows that this is a convergent evolutionary product and has been chosen for many separate occasions.
Defense function
Latex works to protect plants from herbivores. This idea was first proposed in 1887 by Joseph F. James, who notes that latex
... bringing together at the same time such an unpleasant character becomes a better protection against the plant of the enemy than all the thorns, thorns, or hairs that can be provided. In this factory, it is so excessive and very unpleasant to have sap to be that it serves the most important purpose in its economy.
Evidence demonstrating this defense function includes the findings that snails will eat the dried leaves from their latex but are not intact, that many insects cut the blood vessels carrying latex before they feed, and that latex Asclepias humistrata (sandhill milkweed) kills by trapping 30% of newly hatched butterfly caterpillars.
Another evidence is that latex contains 50-1000ÃÆ'â € "higher concentrations of defense substances than other plant tissues. These toxins include those that are toxic to plants and consist of a variety of toxic or "antinutritive" chemicals. Latex is actively transferred to the injured area; in the case of Cryptostegia grandiflora , this can be more than 70 cm.
The nature of latex freezing functions in this defense because it limits waste and sticky trap insects and its mouth.
It has been noted that while there are other explanations for the existence of latex including the storage and movement of plant nutrients, waste, and maintenance of water balance that "[e] none of these functions remains credible and lacks empirical support".
Apps
Latex of many species can be processed to produce many materials.
Natural rubber is the most important product obtained from latex; more than 12,000 plant species produce rubber-containing sap, although in most species the rubber is not suitable for commercial use. Latex is used to make many other products including mattresses, gloves, swimming hats, condoms, catheters and balloons.
Balatá and gutta percha gum contain rubber inelastic polymers.
Latex from cherry and jelutong trees is used in chewing gum.
Dry latex from opium poppy is called opium, the source of some useful alkaloids, such as morphine, codeine and papaverine.
Synthetic latex is used in coatings (eg latex paints) and glue as they solidify by integrating polymer particles when water evaporates, and therefore can form films without releasing potentially toxic organic solvents in the environment. Other uses include cement additives, and to hide information about scratchcards. Latex, usually styrene-based, is also used in immunoassays.
Latex dress
Latex is used in many types of clothing. Worn on the body (or applied directly by painting) tends to be tight, producing a "second skin effect".
Allergic reactions
Some people have serious latex allergies, and latex product exposure such as latex gloves can cause anaphylactic shock. Guayule latex has only 2% of the protein content found in latex Hevea latex, and is being studied as a substitute for lower allergens. In addition, chemical processes can be used to reduce the amount of antigenic proteins in latex Hevea latex, producing alternative materials such as Vytex Natural Rubber Latex that provides significantly reduced exposure to latex allergens.
About half of people with spina bifida are also allergic to natural rubber latex, as well as people who have undergone multiple surgeries, and people who have long been exposed to natural latex.
Environmental impact
Microbial degradation
Several species of the Actinomycetes, Streptomyces, Nocardia, Micromonospora, and Actinoplanes microbe genera are able to consume rubber latex. However, its biodegradation rate is slow, and the growth of bacteria that utilize rubber as a single carbon source is also slow.
See also
- The latex beads
- Natural rubber
- Rubber related topics
References
- Foot Records
- Notes
External links
- Media related to latex in Wikimedia Commons
Source of the article : Wikipedia
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