1.4- cyclohexylene dimethylene terephthalate

One alternative to PET fiber which did compete historically was poly (1,4-cyclohexylene dimethylene terephthalate) (PCT) (Figure 12.5), commercialized under the name Kodel II by Eastman. This polyester gained an early footing because it was not covered by the existing patents, and was able to establish a raw material base from which it could compete both technically and economically. 

Another polyester that has reached longterm commercialization is now produced in limited volume as Kodel 200 by Tennessee Eastman Co. and is considered to be 1-4 cyclohexylene dimethylene terephthalate. The glycol that is used instead of ethylene glycol in this process exists in two isomeric forms, one melting at 43°C and the other at 67°C. This makes possible their separation by crystallization, to secure the desired ratio of the two forms for conversion to the polymer. This ratio determines the melting point of the polymer, a most important property for a material that is to be melt-spun. The polymer from the 100 percent cis form melts at 275°C, and that from the 100 percent trans form at 318°C. Indications are that the commercial product is about 30/70 cis-trans. 

Poly( 1,4-cyclohexylene dimethylene terephthalate-co-isophthalate) (1 1 by mole) 2880... 

PETG poly(ethylene-co-1,4-cyclohexylene dimethylene terephthalate) ... 

Figure 3.9 Relation between measured joint strength and critical surface tension, yc, of the substrate for an epoxy bonding various polymeric substrates [107]. (a) Polytetra-fluoroethylene, (b) poly(vinyl fluoride), (c) polystyrene, (d) poly(vinyl alcohol), (e) poly(vinylidene chloride), (f) poly(vinyl chloride), (g) poly(ethylene terephthalate) and (h) poly (1,4-cyclohexylene dimethylene terephthalate).

Statistical copolymers of ethylene terephthalate (ET) and 1,4-cyclohexylene dimethylene terephthalate (CT) were also found to co-crystallize over a limited composition range [84, 85]. The copolymers rich in ET were found to form a crystalline phase that contained only ET units, while in the copolymers rich in CT, the crystalline phase contained both ET and CT units. The transition between these two crystal phases, as a function of composition, corresponded to a minimum in both copolymer melting temperature and heat of crystallization. It was speculated that the transition occurs at a composition where the energy difference between the melt and the crystal is identical for the two comonomers [85]. 

MC MDI MEKP MF MMA MPEG MPF NBR NDI NR OPET OPP OSA PA PAEK PAI PAN PB PBAN PBI PBN PBS PBT PC PCD PCT PCTFE PE PEC PEG PEI PEK PEN PES PET PF PFA PI PIBI PMDI PMMA PMP PO PP PPA PPC PPO PPS PPSU Methyl cellulose Methylene diphenylene diisocyanate Methyl ethyl ketone peroxide Melamine formaldehyde Methyl methacrylate Polyethylene glycol monomethyl ether Melamine-phenol-formaldehyde Nitrile butyl rubber Naphthalene diisocyanate Natural rubber Oriented polyethylene terephthalate Oriented polypropylene Olefin-modified styrene-acrylonitrile Polyamide Poly(aryl ether-ketone) Poly(amide-imide) Polyacrylonitrile Polybutylene Poly(butadiene-acrylonitrile) Polybenzimidazole Polybutylene naphthalate Poly(butadiene-styrene) Poly(butylene terephthalate) Polycarbonate Polycarbodiimide Poly(cyclohexylene-dimethylene terephthalate) Polychlorotrifluoroethylene Polyethylene Chlorinated polyethylene Poly(ethylene glycol) Poly(ether-imide) Poly(ether-ketone) Polyethylene naphthalate Polyether sulfone Polyethylene terephthalate Phenol-formaldehyde copolymer Perfluoroalkoxy resin Polyimide Poly(isobutylene), Butyl rubber Polymeric methylene diphenylene diisocyanate Poly(methyl methacrylate) Poly(methylpentene) Polyolefins Polypropylene Polyphthalamide Chlorinated polypropylene Poly(phenylene oxide) Poly(phenylene sulfide) Poly(phenylene sulfone)... 

Landry and Henrichs [63] applied dynamic mechanical spectroscopy and H NMR to investigate sub-T motion in polycarbonate(PC)/PMMA and PC/poly(cyclohexylene dimethylene terephthalate)(PCHDMT). Examination of H NMR spectra and relaxation times led them to conclude that local... 

Fig. 19.5. Relationship between the activation energies for viscoelastic relaxation (ilHuA/i ) measured by dynamic mechanical relaxation spectra and those for molecular transport (ilEg) in crystallization for poly(ethylene tetrephthalate) (PET) / poly(l-4-cyclohexylene dimethylene terephthalate) (PCT) copoljmers [48]. Copolymer compositions (PCT/PICT) = 1 100/0, 2 80/20, 3 66/34, 4 5/95, 5 0/100...

Terephthalate polyester ter- o(f)- tha lat, pa-le- es-tor n. Any polymeric ester of ter-ephthalic acid (1,4-benzene dicarboxylic acid), but in particular the three commercially important thermoplastic resins, polyethylene terephthalate, polybutylene terephthalate, and poly-cyclohexylene dimethylene terephthalate. 

Other polymers for which DSC-based studies of crystallinity have been reported include PET [1, 3], ethylene-propylene copolymers [4], PE gels [5], polyazomettine esters [6], polyvinyl alcohol (PVOH) microfibrils [7], polylactides [8], polycyclohexadiene [9], PET-polycarbonate (PC) copolymer [10], PE-like polyesters [11], cyclohexylene dimethylene terephthalate-PET copolymers [12], poly(trimethylene) 2,6-naphthalate [13], and isotactic polypropylene (iPP) [14]. 

PCTA poly(cyclohexylene dimethylene terephthalate) PVE polyfvinyl fluoride)... 

Another class of polyesters are based on cycloaliphatic diols. Eastman Chemical has a broad portfolio of copolyesters where the combination of cycloaliphatic diols, ethylene glycol, iso- and terephthalic moieties are varied. Two will be discussed here. The copolyester poly( 1,4-cyclohexylene-dimethylene... 

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