Is natural rubber a fiber crop? What kind of crop is natural rubber?

Be. Natural rubber is a natural polymer compound with polyisoprene as the main component, the molecular formula is (C5H8)N, and its composition 91 94 is rubber hydrocarbon (polyisoprene), and the rest is protein, fatty acid, ash, sugar and other non-rubber substances. Natural rubber is the most widely used general-purpose rubber.

There are about 2,000 different species of plants in the world that produce polymers similar to natural rubber, and 500 of them have been obtained from different types of rubber, but the real practical value is the clover tree. When the surface of the rubber tree is cut, the milk ducts inside the bark are cut and the latex flows out of the tree. The latex collected from rubber trees is diluted, acid-coagulated, washed, and then tablet, dried, and packaged to produce commercially available natural rubber.

Natural rubber can be made into tobacco sheets, air-dried films, crepe sheets, technical graded rubber and concentrated rubber according to different glue making methods. Standard rubber or granular rubber is a new variety of natural rubber developed in the 60s of the 20th century. In the past, the traditional products of general-purpose cigarette flakes, crepe flakes, and air-dried flakes were all restricted by the development of natural rubber in terms of grading methods and manufacturing methods.

As a result, Malaysia started its standard rubber scheme in 1965 and developed the production of granular rubber on the basis of the use of raw rubber physicochemical property grading. Standard rubber refers to the rubber that is graded according to physical and chemical performance indicators such as mechanical impurities, plasticity retention rate, initial plasticity value, nitrogen content, ash content, ash content, color index, etc. The standard rubber packaging is also more advanced, generally packaged in polyethylene film, and has a clear logo, the weight of the bag is small, and it is easy to move.

The packaging weight in Malaysia is 40kg in China. The grading of standard rubber is more scientific, so this grading method was quickly accepted by the major natural rubber producing countries and international standardization bodies, and the grading standards of standard rubber have been formulated successively. These criteria are largely the same, but not entirely consistent.

For example, ISO2000 stipulates that there are five levels, and China's standard GB8081-87 stipulates that there are four levels.

Trees are fibers, rubber is not fibers.

Natural rubber (NR) is a substance composed mainly of cis-polyisoprene [(C5H8)N] contained in the sap of the rubber tree, which is formed by in vivo addition polymerization reactions. In the juice, a latex is present in which the organic components are dispersed in an aqueous solution, which is then collected, purified, coagulated, and dried, known as raw rubber. Raw rubber is used as an elastomeric material in erasers, for example, but sulfur is used by vulcanization over a wide range of temperatures to soften hard elastomeric materials in the form of cross-linking.

An improvement by vulcanization of elasticity was discovered by Charles Goodyear through 1839. Although polyisoprene, obtained by chemical polymerization of isoprene, is a synthetic rubber, there are some structural differences with polyisoprene of natural rubber. First of all, the cis form of 100 is currently not available with synthetic polyisoprene and contains a small amount of the trans form.

Natural rubber contains trace amounts of proteins and fatty acids in addition to polyisoprene, but synthetic polyisoprene does not have such impurities.

Although natural rubber is mainly made of cis-polyisoprene, what is manufactured from a trans-polyisoprene speakers or ecommia ulmoides gum. Gatapercha is one of the natural resins made from latex, such as the evergreen Gutta Perchanoki (Palaquium Gutta) of the Acate family, which is common in Southeast Asia. Show limits, not gutta percha.

This difference in the elastic limit is due to the nature of the geometric isomer. In other words, cis polyisoprene has a structure in which the molecular chains are curved, so it is likely to be irregularly shaped, and there are many gaps between the molecular chains and relatively small intermolecular forces. In contrast, trans-isolated polyisoprene tends to have a linear structure and short distances between molecular chains.

It acts strongly and causes microcrystallization between molecules, producing a hard resin substance.

However, cis is a sufficient condition to increase the elastic limit. In polyisoprene, cis has a higher elastic limit due to the influence of methyl groups that act as side chains, for example, neoprene rubber is trans but has a higher elastic limit.

It is believed that trace amounts of proteins and fatty acids contained in natural rubber are bonded to the ends of polyisoprene chains.

A: Rubber is a cash crop, natural rubber has strong elasticity and good insulation, and also has the characteristics of plasticity, waterproof, air insulation, tensile resistance and wear resistance, so it is widely used in industry, national defense, transportation, medical and daily life. In the wild, rubber trees can grow to more than 40 meters tall.

In each part of the trunk, there is a mesh of latex ducts that produce yellow or white latex. The phloem near the cambium layer of the trunk is the densest part of the milk duct.

Natural rubber (NR) refers to the rubber obtained from plants, there are about 200 kinds of plants on the earth that can carry out biosynthetic rubber, but only a few have collection value, among which the main one is the Brazilian rubber tree, which is also known as the three-leaf rubber tree, followed by silver chrysanthemum, rubber grass, eucommia, etc.

Tropical crops and fiber crops are just one of the classifications of natural rubber is not a species name Rubber trees belong to tropical plants.

a. Rubber soles belong to rubber (not necessarily synthetic rubber, which is used after the improvement of natural rubber), not synthetic fibers, Azhou.

B. Nylon is a synthetic fiber, C. Cotton is a natural cellulose, which is a natural fiber and a composite material composed of plastic and metal materials

Natural rubber**.

The clover tree provides the most commercial rubber. When it is injured (e.g., the bark of the stem is cut), it secretes a large amount of sap containing rubber emulsion.

In addition, fig trees and some plants of the Euphorbiaceae family can also provide rubber. Germany tried to obtain rubber from these plants during the Second World War due to the cutting off of rubber**, but later switched to producing artificial rubber.

The original rubber trees grew in South America, but after artificial transplantation, there are now large numbers of rubber trees in Southeast Asia. In fact, Asia has become the most important rubber field.

Natural rubber is made from the latex that flows out of the clover rubber tree when it taps rubber through coagulation and drying.

Natural rubber trees, there are a lot of them in Malaysia.

Rubber tree, extracted after condensation of the liquid on the trunk.