1,3-Trimethylene 2,6-naphthalate

Block copolymers of 1,3-trimethylene terephthalate and 1,3-trimethylene 2,6-naphthalate can be formed by the controlled esterification of the homopolymers. By employing this technique, copolymers which exhibit properties consistent with block copolymer formation can be made [40]. The transesterification occurs during film extrusion in a shorter time or at a lower temperature. The desired blend can be formed without added catalyst. 

Chuah et al. [107] prepared a series of PTT/poly(trimethylene napthalate) (PTN) copolyesters by copolymerizing PDO with dimethyl terephthalate and dimethyl naphthalate. The PTN homopolymer has a 7 g of 75 °C and a Tm of 245 °C. Despite the more rigid napthalate moiety, the PTN Tg and Tm were much lower than the Tg of poly(ethylene naphthalate) (PEN), indicating the strong influence of the flexible trimethylene units. 

It should be taken into account that all of the aspects described above are of a general nature and therefore more or less valid for any kind of industrially relevant polyester resin. Upon closer examination, the experiences gained with PET are particularly applicable to poly(butylene terephthalate) (PBT), poly(trimethylene terephthalate) (PTT) and polyethylene naphthalate) (PEN). These polymers have gained major industrial importance as a result of a number of different properties in comparison with PET. 

P. Krutphun and P. Supaphol. Thermal and crystallization characteristics of poly(trimethylene terephthalate)/poly(ethylene naphthalate) blends. Eur. Polym. J., 41(7) 1561-1568, July 2005. 

The relaxation behavior of poly(trimethylene 2,6-naphthalate)/nanoclay composites has been investigated by DSC and dynamic mechanical analysis [81]. The incorporation of two different types of nanoclays in the polymer matrix intercalates the chains in the... 

Simmons AH. Block copolymers comprising poly(l,3-trimethylene terephthalate) and poly(l,3-trimethylene 2,6-naphthalate). US Patent Application 20120126454, assigned to El. du Pont de Nemours and Company, Wilmington, DE 2012. 

Khan AN, Hong PD, Chaung WT. Relaxation behavior of poly(trimethylene 2,6-naphthalate) in nanoclay confinement. J Polym Res 2013 20(10) 281-92. 

Many articles have been published on the hydrolytic degradation of poly(ethylene terephthalate) (PET) under acidic conditions [1-20] and basic conditions [21-30], but far fewer on similar degradation studies on poly(butylene terephthalate) (PBT) [31, 32], poly(trimethylene terephthalate) (PTT) [33] and poly(ethylene naphthalate) (PEN) [34, 35],... 

Materials covered include well-known polyesters such as poly(ethylene terephthalate) and poly(butylene terephthalate), through the less well-known poly(alkylene naphthalate)s and liquid crystalline polyesters, to new substances sucb as poly(trimethylene terephthalate). 

In terms of tonnage and use, poly(ethylene terephthalate) is these days virtually a commodity plastic, with widespread, large volume, use in food packaging, beverage bottle and fibres. Other aromatic polyesters have increased in volume production over the last decade or so, such as poly( butylene terephthalate) and poly(ethylene naphthalate). There is also the promise of large quantity use of the most recently commercialised member of the family, poly (trimethylene terephthalate). 

Hwo, C., Forschner, T., Lowtan, R., Gwyn, D., and Barry, C. Poly(trimethylene phthalates or naphthalate) and Copolymers New Opportunities in Frhn and Packaging Apphcations, In Shell Chemicals, Proceedings of the Future-Pak 98 Conference, Chicago, USA, November pp. 10-12(1998). lijima, S. Nature, 354,56-58 (1991). 

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]. 

Melting behaviour studies. These have been carried out on PET and PET-cyclohexylenedimethyl terephthalate copolymers [12] and poly(trimethylene-2,6-naphthalate) [13]. 

Acronyms and variables cold crystalhzation (CC) cobalt molybdenum catalyst (CoMoCAT) chemical vapor deposition (CVD) dichlorobenzene (DCB) high-pressure carbon monoxide (HiPCO) isotactic polypropylene (iPP) melt crystalhzation (MC) melt flow index (MFl) poly( -caprolactone) (PCL) polydispersity index (PDD polyethylene (PE) polyethylene oxide (PEO) poly (ethylene-propylene-diene) [P(E-PP-diene)] poly(ethylene 2,6-naphthalate) (PEN) poly(ethylene terephthalate (PET) poly(L-lactic acid) (PLLA) poly(trimethylene terephthalate (PTMT) poly(vinyl alcohol) (PVA) 1,1,2,2-tetrachloroethane (TCE) tetrahydrofuran (THE) weight-average molecular weight = ] number-average molecular weight Avrami exponent for neat polymer = Avrami exponent for CNT composite = Avrami rate constant for neat polymer = Avrami exponent for composite = neat polymer crystalhzation... 

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