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Polycarbonates plastics

Eyeglass frames made of cellulose acetate plasticized with diglycerol esters do not exhibit opaqueness at the frame-lens junction with polycarbonate plastic lenses (146,147). [Pg.259]

A component of polycarbonate plastics and epoxy resins used to line food cans... [Pg.14]

Hollomon s ethos, combined with his ferocious energy and determination, and his sustained determination to recruit only the best researchers to join his group, over the next 15 years led to a sequence of remarkable innovations related to materials, including man-made diamond, high-quality thermal insulation, a vacuum circuit-breaker, products based on etched particle tracks in irradiated solids, polycarbonate plastic and, particularly, the Lucalox alumina envelope for a metal-vapour lamp. (Of course many managers besides Hollomon were involved.) A brilliant, detailed account of these innovations and the arrangements that made them possible was later written by Guy Suits and his successor as director, Arthur Bueche (Suits and Bueche 1967). Some of these specific episodes will feature later in this book, but it helps to reinforce the points made here about Hollomon s coneeption of broad research on materials if I point out that the invention of translucent alumina tubes for lamps was... [Pg.9]

Canada (2008) Government of Canada acts to protect new boms and infants from Bipshenol A in polycarbonate plastic baby bottles, http //hc-sc.gc.ca/ahc-asc/media/nr-cp/ 2009/ 2009 106-eng.php... [Pg.28]

Paper mill whitewaters and effluents are rich in bisphenol A (BPA), which is used in great quantities for the production of epoxy resins and polycarbonate plastics. Its presence in effluents has been reported as a result of its use in the manufacture of thermal paper or due to migration from plastic containers at the high water temperatures of whitewaters [35]. This compound is preferably analysed by GC-MS. The levels encountered in paper mill effluents are between 28 and 72 pg/L [36,37]. Another study revealed levels up to 226 pg/L [33]. Special in vitro test systems and animal experiments have demonstrated a weak oestrogenicity for BPA. Since aquatic wildlife could be endangered by paper mill waste discharges at the concentration that BPA is found, its survey in paper mill effluents should be taken into consideration. [Pg.41]

The result was the compact disc (CD). Made from 1.2 mm of polycarbonate plastic, the disc is coated with a much thinner aluminum layer that is then protected with a film of lacquer. The lacquer layer (10) can be printed with a label. CDs are typically 120 mm in diameter, and can store about 74 minutes of music. There are also discs that can store 80, 90, 99, and 100 minutes of music, but they are not as compatible with various stereos and computers as the 74—minute size. [Pg.15]

Phenol is also used to manufacture several important monomers. Bisphenol A, a phenol derivative, is used to make very strong polycarbonate plastics and epoxy resins (the kind you buy in two tubes and mix to make glue). Ocher applications of epoxy resins include paints, fiberglass binder, and construction adhesives. [Pg.115]

Bisphenol A, a compound highly used in the production of epoxy resins and polycarbonate plastics, forms monochloro-, dichloro, trichloro-, and tetrachloro derivatives when chlorinated [127], Its reaction with ozone produces as major transformation products, catechol, orthoquinone, muconic acid derivatives of bisphenol A, benzoquinone, and 2-(4-hydroxyphenyl)-propan-2-ol [128],... [Pg.118]

Another large molecule of potential interest would be anions derived from Bisphenolacetone (Figure 8) S)mthesis (Eqn 7), notable reactions to produce polycarbonate (Eqn. 8) or epoxy resins (Eqn. 9). As reviewed recently elsewhere [45]. Bisphenol A (BPA), the s)mthesis of which is shown (Eqn. 7), is a component in the s)mthesis of polycarbonate plastics and epoxy resins (Eqn. 8, 9) that have a variety of significant uses. [Pg.136]

Another use of acetone in the chemical industry is for bisphenol A ( ). BPA results form the condensation reaction of acetone and phenol in the presence of an appropriate catalyst. BPA is used in polycarbonate plastics, polyurethanes, and epoxy resins. Polycarbonate plastics are tough and durable and are often used as a glass substitute. Eyeglasses, safety glasses, and varieties of bullet-proof glass are made of polycarbonates. Additional... [Pg.5]

Solubility sol in acet, DMFA, DMSO, N-methylpyrroBdohe sl sol in ethand, pyridine, insd in benz, carbon disulfide, carbon tetrachloride, chlf, ethyl acetate, ethyl-eth w Detonation Properties Charge radius affects the detonation velocity of 1. Sg/cc XTX-8004 confined in polycarbonate plastic in a hemispherical configuration as follows (Ref 1) ... [Pg.413]

While the EPA used to list DEHA as a toxic chemical, for some reason it no longer does. But we re not convinced. We want more concrete evidence that a chemical formerly labeled toxic won t harm us when it leaches out of plastic, especially when we re pregnant or breastfeeding. Exercising caution when it comes to plastic makes even more sense when you take into account another study done by Dr. Patricia Hunt in the April 2003 issue of Current Biology, which reported that exposure to bisphenol-A (BPA) causes a chromosomal abnormality in the oocytes, or egg cells, of female mice. Polycarbonate plastic ( 7), used for everything from glasses to bowls, is manufactured with bisphenol-A. [Pg.104]

When you must use plastics, choose 2 high-density polyethylene (HDPE), 4 low-density polyethylene (LDPE), and 5 polypropylene (PP). These types of plastics are not known to leach harmful chemicals. Avoid 3 polyvinyl chloride (PVC), 6 polystyrene (PS), and 7 polycarbonate. Plastic bottles made from 1 polyethylene terephthalate (PET or PETE) are for single, not multiple, use. [Pg.104]

Next, a crisis in plastic bottles occurred in early 2008 in the U.S., Canada and elsewhere. Consumers are concerned about the use of BPA or bisphenol-a, which is commonly used in the manufacture of the hard, clear polycarbonate plastic bottles used for juices, drinks and other liquids. Many manufacturers promptly announced they would no longer use BPA. Environmental concerns, health concerns and consumer backlash regarding packaging will grow in coming years. [Pg.38]

Environmental exposures may contribute to recent increases in the rate of type 2 diabetes. For example, there is a positive correlation between concentration in the urine of bisphenol A, a constituent of polycarbonate plastic, and the incidence of type 2 diabetes. [Pg.49]

Polycarbonate plastic has a density of 1.2 g/cm. A photo frame is constructed from two... [Pg.876]

Originally synthesized in 1891 and was investigated in the 1930s as a possible synthetic estrogen. Currently, the primary use is in the manufacture of polycarbonate plastics and epoxy resins for coatings on metal cans to maintain the quality of canned food and beverages. Also used as a thermal stabilizer in PVC compounds and as a dental sealant. [Pg.192]

Low levels may be released to the environment in the effluent water from biological wastewater treatment plants. Scientists have known for many years that the polycarbonate bond created by BPA is unstable and that the chemical will eventually leach into food or beverages in contact with die plastic. The obvious concern today is that it may leach into food products, ranging from microwavable dinners to baby formula, that are packaged in polycarbonate plastic. [Pg.192]

A second coating of nickel is then electrodeposited onto the mother disc. This nickel layer, the stamper master, is peeled off and used to stamp the data impression onto melted polycarbonate plastic discs. The polycarbonate disc now has all of the pits found on the original glass master disc etched by the laser. Because polycarbonate is clear, it is vacuum coated with a thin aluminum film to produce the reflective layer required by the laser. This delicate aluminum layer is covered with a protective layer of polycarbonate to prevent aluminum oxidation and marring of the data surface. The back of the CD can now be covered with information in the form of art and lettering. [Pg.594]

The effects may be subtle and cumulative and may be noticeable only after a long time. Even the synthetic fibers or plastic goods used in clothing and sleepwear, as well as mattresses, may have minute effects on body and brain functions. Additives used in plastic containers or bottles are suspected to leach into the contents. For example, Disphenyl A, used in clear polycarbonate plastics such as in the lining of beverage cans, may mimic hormones. Not to mention the many electromagnetic... [Pg.44]


See other pages where Polycarbonates plastics is mentioned: [Pg.521]    [Pg.778]    [Pg.155]    [Pg.281]    [Pg.302]    [Pg.436]    [Pg.309]    [Pg.111]    [Pg.358]    [Pg.713]    [Pg.17]    [Pg.609]    [Pg.255]    [Pg.412]    [Pg.108]    [Pg.73]    [Pg.201]    [Pg.325]    [Pg.372]    [Pg.318]    [Pg.12]    [Pg.613]    [Pg.174]    [Pg.302]    [Pg.159]    [Pg.314]    [Pg.314]    [Pg.1016]    [Pg.1348]    [Pg.232]    [Pg.642]   
See also in sourсe #XX -- [ Pg.115 ]




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Polycarbonate, plasticization

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