Poly l ,4-cyclohexanedimethylene

PCTA Copolyester. Poly(l,4-cyclohexanedimethylene terephthalic acid) (PCTA) copolyester is a polymer of cyclohexanedimethanol and terephthalic acid, with another acid substituted for a portion of the terephthalic acid otherwise required. It has the following formula ... 

Brink, A. E., Turner, S. R. and Keep, G. T Poly(alkylene ether)s as plasticizers and flow aids in poly(l,4-cyclohexanedimethylene terephthalate) resins, US Patent 5 965 648, 1999. 

Studies have been carried out on the UV degradation of poly(ethylene-co-l,4-cyclohexanedimethylene terephthalate) [35,38,56]. The PET sections of the chain will undergo the various initiation, abstraction and oxidation processes already considered, but a tertiary hydrogen on the cyclohexane ring of the poly(l,4-cyclohexanedimethylene terephthalate) units means that formation of tertiary alkyl radicals and subsequent autoxidation at this site will predominate over formation of secondary alkyl radicals on methylene units or elsewhere... 

Poly(ethylene-co-1,4-cyclohexane dimethylene terephthalate) The thermal and photochemical oxidation processes of a polyester based on poly(ethylene-co-l,4-cyclohexanedimethylene terephthalate) (PECT) with approximately 30% of 1,4-cyclohexanedimethanol have been studied by means of chemiluminescence [88], Also, the stabilization activity of some commercial antioxidants has been evaluated, and it has been related to hydroperoxide levels in the polymer. 

Poly(ethylene-l,4-cyclohexanedimethylene arylate), 359 Poly(3,4-ethylenedioxythiophene), 109 Poly(ethylene glycol), 9 Poly(ethylene glycol diacrylate), 540 Poly(ethylene naphthalate), 29, 347, 349 Poly(ethylene oxide), 430, 499 Poly(elhylene terephthalate), 185, 256, 347, 351, 398 Poly(iV-elhyl-3-vinylcarbazole), 14 Poly(furfirryl alcohol), 162 Poly(l-hexyl-3,4-dimethyl-3,5-pyrrolylene), 22... 

The preferred synthesis route for these copolymers is transesterification. There are two steps in the preparation of poly(ethylene-l,4-cyclohexanedimethylene arylate) (PECA). 

Stabilisers of this type have been claimed as extremely effective UV absorbers for poly(ethylene-co-l,4-cyclohexanedimethylene terephthalate) [98-100], allowing the use of this material in outdoor applications. Developments in novel synthesis methods have improved the inherent stability of this class of additive, paving the way towards their more effective use in aromatic polyesters [101-106]... 

---