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|Section2= |Section3= }} 2,2,4,4-Tetramethyl-1,3-cyclobutanediol (CBDO) is an aliphatic diol. This diol is produced as a mixture of ''cis''- and ''trans''-isomers, depending on the relative stereochemistry of the hydroxyl groups. It is used as a monomer for the synthesis of polymeric materials. CBDO is currently being researched as an alternative to bisphenol A (BPA). BPA is a precursor used in the production of a wide range of polymers including polycarbonates, polyesters, polysulfones, and polyester ketones. ==Replacement for BPA== The controversies associated with BPA in large quantities are ultimately related to its endrocrine disrupting abilities.〔 vom Saal Frederick S., Hughes Claude. An Extensive New Literature Concerning Low-Dose Effects of Bisphenol A Shows the Need for a New Risk Assessment. Environ. Health Perspective. Volume 113, 2005, pp. 926–33.〕 Like BPA, CBDO is a diol with a structure suitable for making polyesters. CBDO’s C4 ring is sufficiently rigid to prevent the two OH groups from forming cyclic structures. Unlike BPA, there is no current evidence of carcinogenic or toxic effects from CBDO-based consumer products. There are, however, few studies on the toxicology of CBDO for both long term and short term effects. CBDO has potential advantages relative to BPA as a building block for production of polyesters. CBDO is very stable thermally and mechanically. Polyesters prepared from CBDO are rigid materials, but the combination of CBDO with flexible diols results in materials with high impact resistance, low color, thermal stability, good photooxidative stability and transparency.〔Hoppens, Nathan C., Hudnall, Todd W., Foster, Adam, Booth, Chad J. Aliphatic-aromatic copolyesters derived from 2,2,4,4-tetramethyl-1,3-cyclobutanediol. Journal of Polymer Science: Part A: Polymer Chemistry. Volume 42, 2004, pp. 3473-3478. 〕 As an added bonus, CBDO-derived polymers have high ductility.〔Kelsey, Donald R., Scardion, Betty M., Grebowicz, Jamusz S., Chuah, Hoe H. High Impact, Amorphous Terephthalate Copolyesters of Rigid 2,2,4,4-Tetramethyl-1,3-cyclobutanediol with Flexible Diols. Macromolecules. Volume 33, 2000, pp. 5810-5818.〕 The thermal and mechanical properties of CBDO-derived polyesters are often superior to conventional polyesters.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「2,2,4,4-Tetramethyl-1,3-cyclobutanediol」の詳細全文を読む スポンサード リンク
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