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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2014/12/09 23:09:12」(JST)

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A polyol is an alcohol containing multiple hydroxyl groups. In two technological disciplines the term "polyol" has a special meaning: food science and polymer chemistry.

Food science

Sugar alcohols, a class of polyols, are commonly added to foods because of their lower caloric content than sugars; however, they are also, in general, less sweet, and are often combined with high-intensity sweeteners. They are also added to chewing gum because they are not broken down by bacteria in the mouth or metabolized to acids, and thus do not contribute to tooth decay.^[1] Maltitol, sorbitol, xylitol, erythritol, and isomalt are some of the more common types. Sugar alcohols may be formed under mild reducing conditions from their analogue sugars.

Polymer chemistry

In polymer chemistry, polyols are compounds with multiple hydroxyl functional groups available for organic reactions. A molecule with two hydroxyl groups is a diol, one with three is a triol, one with four is a tetrol and so on.

Monomeric polyols such as glycerin, pentaerythritol, ethylene glycol and sucrose often serve as the starting point for polymeric polyols. These materials are often referred to as the "initiators" and reacted with propylene oxide or ethylene oxide to produce polymeric polyols. However, they should not be confused with free radical "initiators" used to promote other polymerization reactions. The functional group used as the starting point for a polymeric polyol need not be a hydroxyl group; there are a number of important polyols which are built up from amines. A primary amino group (-NH₂) often functions as the starting point for two polymeric chains, especially in the case of polyether polyols.

Polymeric polyols are generally used to produce other polymers. They are reacted with isocyanates to make polyurethanes used to make mattresses, foam insulation for appliances (refrigerators and freezers), home and automotive seats, elastomeric shoe soles, fibers (e.g. Spandex), and adhesives.^[2]

Polymeric polyols are usually polyethers or polyesters. Polyether polyols are made by reacting epoxides like ethylene oxide or propylene oxide with the multifunctional initiator in the presence of a catalyst, often a strong base such as potassium hydroxide or a double metal cyanide catalyst such as zinc hexacyanocobaltate-t-butanol complex.^[3] Common polyether diols are polyethylene glycol, polypropylene glycol, and poly(tetramethylene ether) glycol. The examples shown below are fairly low molecular weight triols based on glycerin (a triol) being reacted with propylene oxide, ethylene oxide or a combination of the two. In reality, the chains would not be of equal length in any one molecule and there would be a distribution of molecular weight polyols within the material. Polyether polyols account for about 90% of the polymeric polyols used industrially; the balance is polyester polyols.^[4]

Another class of polymeric polyols is the polyesters. Polyesters are formed by condensation or step-growth polymerization of diols and dicarboxylic acids (or their derivatives), for example diethylene glycol reacting with phthalic acid.^[5] Alternatively, the hydroxyl group and the carboxylic acid (or their derivatives) may be within the same molecule, as in the case of caprolactone. The example below is an idealized structure that could be obtained by reacting pentaerythritol (a tetrol) with gamma-butyrolactone.

Hydroxyl-terminated polybutadiene is a polyol used to produce polyurethane. Polyester polyols from vegetable oils, known as natural oil polyols or NOPs, are replacing some epoxide-based polyols.

References

^ "Polyols information source". www.Polyol.org. Retrieved 2010-03-10.
^ Chinn, Henry; Akihiro Kishi and Uwe Loechner (April 2006). "Polyether Polyols for Urethanes (abstract only without subscription)". SRI Consulting. Cite uses deprecated parameters (help)
^ Alper, H.; J. L. Garcia; E. J. Jang (4 September 2002). "New heterogeneous catalysis for the synthesis of poly(ether polyol)s" (abstract). Journal of Applied Polymer Science 86 (7): 1553–1557. doi:10.1002/app.10996. Retrieved 2008-08-09.
^ "Dow Polyurethanes and Thermoset Systems, uses and innovations". Archived from the original on 2007-09-13. Retrieved 2007-09-14.
^ Kaszynski, Poitr; Oleg Kadkin; Karol Osajda; Thomas A. Barber (2003). "Polyester Polyols: Synthesis and Characterization of Diethylene Glycol Terephthalate Oligomers" (PDF). Journal of Polymer Science: Part A: Polymer Chemistry 41 (8): 1114–1123. Bibcode:2003JPoSA..41.1114K. doi:10.1002/pola.10655. Retrieved 2008-08-09.

UpToDate Contents

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English Journal

Synthesis, characteristics and sonocatalytic activities of calcined γ-Fe2O3 and TiO2 nanotubes/γ-Fe2O3 magnetic catalysts in the degradation of Orange G.

Pang YL1, Lim S2, Ong HC3, Chong WT3.
Ultrasonics sonochemistry.Ultrason Sonochem.2016 Mar;29:317-27. doi: 10.1016/j.ultsonch.2015.10.003. Epub 2015 Oct 9.
In this work, γ-Fe2O3 and TiO2 NTs/γ-Fe2O3 composites with good magnetism and sonocatalytic activity were prepared by a facile polyol method and utilize the principle of isoelectric point method, respectively. The structural and magnetic features of the prepared calcined γ-Fe2O3 and composite cat
PMID 26585012

Sonochemical assisted synthesis of SrFe12O19 nanoparticles.

Palomino RL1, Bolarín Miró AM1, Tenorio FN1, Sánchez De Jesús F2, Cortés Escobedo CA3, Ammar S4.
Ultrasonics sonochemistry.Ultrason Sonochem.2016 Mar;29:470-5. doi: 10.1016/j.ultsonch.2015.10.023. Epub 2015 Oct 31.
We present the synthesis of M-type strontium hexaferrite by sonochemistry and annealing. The effects of the sonication time and thermal energy on the crystal structure and magnetic properties of the obtained powders are presented. Strontium hexagonal ferrite (SrFe12O19) was successfully prepared by
PMID 26548841

Volumetric and UV absorption studies on understanding the solvation behavior of polyhydroxy solutes in l-ascorbic acid(aq) solutions at T=(288.15 to 318.15)K.

Banipal PK1, Sharma M2, Banipal TS2.
Food chemistry.Food Chem.2016 Feb 1;192:765-74. doi: 10.1016/j.foodchem.2015.07.072. Epub 2015 Jul 18.
Thermodynamic and spectroscopic data characterizing the solvation behavior of polyhydroxy compounds are in demand to get better understanding about the mechanisms of taste chemoreception, protein stabilization, etc. Apparent molar volumes for monosaccharides, disaccharides, derivatives, and polyols
PMID 26304409

Japanese Journal

構造解明を指向したポリオール天然物シンビオジノライドの合成研究

髙村浩由,門田功,上村大輔
有機合成化学協会誌 72(1), 6-17, 2014-01
NAID 40019946453

Development of Self-Assembling Alternating Amphiphilic Compounds

Muraoka Takahiro,Sadhukhan Nabanita,Li Rui [他]
Journal of photopolymer science and technology 27(5), 557-560, 2014
NAID 40020132863

Development of Self-Assembling Alternating Amphiphilic Compounds

Muraoka Takahiro,Sadhukhan Nabanita,Li Rui,Kinbara Kazushi
Journal of Photopolymer Science and Technology 27(5), 557-560, 2014
Synthesis and self-assembling properties of alternating amphiphilic compounds 1 and 2 were reported. 1 and 2 are consisting of a hydrophilic hexaol core, a tripentaerythritol unit, bearing two hydrop …
NAID 130004691083