Cyclohexanedimethanol
{{Chembox
| Verifiedfields = changed
| Watchedfields = changed
| verifiedrevid = 443929860
| ImageFile = CHDMisomers.png
| IUPACName = [4-(hydroxymethyl)cyclohexyl]methanol
| PIN = (cyclohexane-1,4-diyl)dimethanol
| OtherNames = 1,4–Cyclohexanedimethanol; CHDM; 1,4-Bis(hydroxymethyl)cyclohexane
|Section1={{Chembox Identifiers
| CASNo = 105-08-8
| CASNo_Ref = {{cascite|correct|CAS}}
| UNII_Ref = {{fdacite|changed|FDA}}
| UNII = 8C3FKR6R1B
| PubChem = 7735
| ChemSpiderID_Ref = {{chemspidercite|changed|chemspider}}
| ChemSpiderID = 7449
| SMILES = C1CC(CCC1CO)CO
| InChI = 1/C8H16O2/c9-5-7-1-2-8(6-10)4-3-7/h7-10H,1-6H2
| InChIKey = YIMQCDZDWXUDCA-UHFFFAOYAS
| StdInChI_Ref = {{stdinchicite|changed|chemspider}}
| StdInChI = 1S/C8H16O2/c9-5-7-1-2-8(6-10)4-3-7/h7-10H,1-6H2
| StdInChIKey_Ref = {{stdinchicite|changed|chemspider}}
| StdInChIKey = YIMQCDZDWXUDCA-UHFFFAOYSA-N}}
|Section2={{Chembox Properties
| Formula = C8H16O2
| MolarMass = 144.21 g/mol
| Appearance = White waxy solid
| Density = 1.02 g/ml
| MeltingPtC = 41 to 61
| BoilingPtC = 284 to 288
| Solubility = }}
|Section3={{Chembox Hazards
| MainHazards =
| FlashPt =
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Cyclohexanedimethanol (CHDM) is a mixture of isomeric organic compounds with formula C6H10(CH2OH)2. It is a colorless low-melting solid used in the production of polyester resins. Commercial samples consist of a mixture of cis and trans isomers. It is a di-substituted derivative of cyclohexane and is classified as a diol, meaning that it has two OH functional groups. Commercial CHDM typically has a cis/trans ratio of 30:70.
Production
CHDM is produced by catalytic hydrogenation of dimethyl terephthalate (DMT). The reaction conducted in two steps beginning with the conversion of DMT to the diester dimethyl 1,4-cyclohexanedicarboxylate (DMCD):
:C6H4(CO2CH3)2 + 3 H2 → C6H10(CO2CH3)2
In the second step DMCD is further hydrogenated to CHDM:
:C6H10(CO2CH3)2 + 4 H2 → C6H10(CH2OH)2 + 2 CH3OH
A copper chromite catalyst is usually used industrially.{{cite journal
| title = Synthesis and Properties of Cyclic Diester Based Aliphatic Copolyesters
| author1=S.R. Turner | author2=Y. Li | journal = Journal of Polymer Science Part A: Polymer Chemistry
| volume = 48
| pages = 2162–2169
| year = 2010
| issue=10 | url =
| doi = 10.1002/pola.23985}}
The cis/trans ratio of the CHDM is affected by the catalyst.{{cite journal
| title = The materials Chemistry of Inorganic Catalyst
| author1=J. M. Thomas | author2=R. Raja | journal = Australian Journal of Chemistry
| volume = 54
| pages = 551–560
| year = 2002
| url =
| doi = 10.1071/CH01150}}
Byproduct of this process are 4-methylcyclohexanemethanol (CH3C6H10CH2OH) and the monoester methyl
4-methyl-4-cyclohexanecarboxylate (CH3C6H10CO2CH3, CAS registry number 51181-40-9).Peter Werle, Marcus Morawietz, Stefan Lundmark, Kent Sörensen, Esko Karvinen and Juha Lehtonen "Alcohols, Polyhydric" Ullmann's Encyclopedia of Industrial Chemistry, 2008, Wiley-VCH, Weinheim. {{doi|10.1002/14356007.a01_305.pub2}} The leading producers in CHDM are Eastman Chemical in US and SK Chemicals in South Korea.
Applications
Via the process called polycondensation, CHDM is a precursor to polyesters. It is one of the most important comonomers for production of polyethylene terephthalate (PET), or polyethylene terephthalic ester (PETE), from which plastic bottles are made.{{cite journal
| title = Development of amorphous copolyesters based on 1,4- cyclohexane-dimethanol
| author = S.R. Turner
| journal = Journal of Polymer Science Part A: Polymer Chemistry
| volume = 42
| pages = 5847–5852
| year = 2004
| issue = 23
| url =
| doi = 10.1002/pola.20460| doi-access = free
}}
| title = Mini-review The Polyoxaesters
|author1=S. Andjelic |author2=D.D. Jamiolkowski |author3=R. Bezwada | journal = Polymer International
| volume = 56
| pages = 1063–1077
| year = 2007
| url =
| doi = 10.1002/pi.2257}}
In addition it maybe spun to form carpet fibers.{{Cite web |last=Hatton |first=|title=Nylon vs. Polyester Carpet Fibers: Comparison Guide |url=https://www.homedit.com/flooring/carpet/fibers/nylon-vs-polyester/ |access-date=2023-08-17 |website=Homedit |language=en-US}}
Thermoplastic polyesters containing CHDM exhibit enhanced strength, clarity, and solvent resistance. The properties of the polyesters vary from the high melting crystalline poly(1,4-cyclohexylenedimethylene terephthalate), PCT, to the non-crystalline copolyesters derived from both ethylene glycol and CHDM. The properties of these polyesters also is affected by the cis/trans ratio of the CHDM monomer.{{cite journal
| title = Cyclohexanedimethanol Polyesters
| author = S. R. Turner
| author2 = R.W. Seymour
| author3 = T.W. Smith
| journal = Encyclopedia of Polymer Science and Technology
| pages =
| year = 2001
| url =
| doi = 10.1002/0471440264.pst257| isbn = 0471440264
}}
CHDM reduces the degree of crystallinity of PET homopolymer, improving its processability. The copolymer tends to resist degradation, e.g. to acetaldehyde. The copolymer with PET is known as glycol-modified polyethylene terephthalate, PETG. PETG is used in many fields, including electronics, automobiles, barrier, and medical, etc.
CHDM is a raw material for the production of 1,4-cyclohexanedimethanol diglycidyl ether, an epoxy diluent.{{Cite journal |last=Crivello |first=James V. |date=2006 |title=Design and synthesis of multifunctional glycidyl ethers that undergo frontal polymerization |url=https://doi.org/10.1002/pola.21761 |journal=Journal of Polymer Science Part A: Polymer Chemistry |volume=44 |issue=21 |pages=6435–6448 |doi=10.1002/pola.21761 |bibcode=2006JPoSA..44.6435C |issn=0887-624X|url-access=subscription }} The key use for this diglycidyl ether is to reduce the viscosity of epoxy resins.{{Citation |last=Monte |first=Salvatore J. |title=Diluents and viscosity modifiers for epoxy resins |date=1998 |url=https://doi.org/10.1007/978-94-011-5862-6_24 |work=Plastics Additives: An A-Z reference |series=Polymer Science and Technology Series |volume=1 |pages=211–216 |editor-last=Pritchard |editor-first=Geoffrey |place=Dordrecht |publisher=Springer Netherlands |language=en |doi=10.1007/978-94-011-5862-6_24 |isbn=978-94-011-5862-6 |access-date=2022-03-29 |archive-date=2022-04-11 |archive-url=https://web.archive.org/web/20220411203514/https://link.springer.com/chapter/10.1007/978-94-011-5862-6_24 |url-status=live |url-access=subscription }}
References
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External links
- [http://toxnet.nlm.nih.gov/cgi-bin/sis/search/r?dbs+hsdb:@term+@na+@rel+1,4-cyclohexanedimethanol U.S. National Library of Medicine: Hazardous Substances Databank – 1,4-cyclohexanedimethanol]