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| Chinese name：Bisphenol-a |
| English name：双酚A |
| Price：RMB 14800/mt |
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| Traits： |
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| It is the flammable white grain with slight phenol smell, dissolving in the ethanol and dilute alkali, being slightly soluble in carbon tetrachloride, being insoluble in water, 1.195（25/25℃） for specific gravity, 153℃ for melting point, 220℃ for boiling point, and 175℉ for flash point. |
| Specifications： |
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Molten color, APHA No. |
20 max. |
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Appearance |
white prills |
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Puriry, wt % |
99.85 min. |
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Phenol, wt ppm |
100 max. |
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o,p-Isomer, wt ppm |
500 max. |
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Water, wt ppm |
1,000 max. |
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Iron, wt ppm |
0.1 max. |
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Freezing point, ℃ |
156.5 min. |
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Solution Color, APHA No. |
10 max. | |
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| Packaging： |
| PP: 25kg per bag |
| Use： |
| Bisphenol A is the main ingredient used for production of polycar-bonate, epoxy, unsaturated polyester, and polysulfone resins. The scheme below illustrates the process of synthesis of polycarbonate resins.
Bisphenol A is also used as a component of synthetic plastic mate-rials, e.g. poly(vinyl chloride) [12,13], and as an antioxidant in glues, plastics, and ink. In 2001 global production of BPA (started in 1957 in the USA) was estimated to be approximately 2.5 million tons.
Materials containing BPA have been used for many applications, for example as a varnish on the inside of cans and as other packaging used for storage of food products, beverages, and pharmaceuticals.Po-lycarbonates have been commonly used for production of components of medical equipment (for dialysis and blood oxygenation), bottles for feeding infants, and kitchen dishes. The wide use of polycarbonates follows mainly from their particular properties – light weight, durability, high tensile strength, high modulus of elasticity, high melting point, and high vitrification tem-perature . Products made of polycarbonates should be marked with the symbol. |
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| Other： |
For many years BPA was treated as neutral to human health. De-tection of BPA in the natural environment, in drinking water, and in food products (since 1990) has, however, aroused the interest of many resear-chers. At almost the same time a negative effect of this compound on human health was established. Consequently, in 1996 BPA was classified by the European Commission as a substance of external origin with a harm-ful effect on human health. Numerous toxicological and biochemical studies have confirmed that bisphenol A has estrogenic properties and an agonistic effect toward the estrogenic receptor. In recent studies bisphenol A was classified as a xenobiotic disturbing hormonal balance in humans and other animals, a so-called endocrine disruptor. Bisphenol A has been proved to have estrogenic activity even at concentrations below 1 ng L−1 .
Because of the complexity of the hormone system, the mechanisms of xenobiotic activity leading to endocrine disruption are difficult to iden-tify and are not yet known. The effects of exposure to bisphenol A can be particularly harmful to the fetus, infants, and young children, because of lack of feedback regulating the activity, synthesis, and elimination of hor-mones. Contact with BPA at that time may lead to irreversible changes appearing even after much delay. A study on mice revealed that a concen-tration of BPA as low as 20 ppm in drinking water is sufficient to bring about genetic changes in mice fetuses. The changes are mainly a result of disturbance of the distribution of chromosomes in the daughter cells. As a consequence of such changes in mice ovum cells, and hence in fetuses, there may be too many or too few chromosomes. In humans, disturbances of this type are the main reason for miscarriages and genetic defects, e.g. Down’s syndrome. Although dangerous effects of BPA on human ovum cells have not yet been established, the processes involved in the creation of ovum cells in humans and mice are similar, so one might foresee that BPA is very dangerous for humans also. |
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