PET copolyesters

CHDA CHDM DMCD EG IPA N NDA PCT PCTA PCTG PET PETG TMCD TPA cis/trans-1,4-cyclohexanedicarboxylic acid cis/trans-1,4-cyclohexanedimethanol dimethyl cis/trans-1,4-cyclohexanedicarboxylate ethylene glycol isophthalic acid dimethyl 2,6-naphthalenedicarboxylate 2,6-naphthalenedicarboxylic acid poly(1,4-cyclohexylenedimethylene terephthalate) dibasic-acid-modified PCT copolyester glycol-modified PCT copolyester poly(ethylene terephthalate) CHDM-modified PET copolyester c .S / ra .v-2,2,4,4-tetramethyl-l,3-cyclobutancdiol terephthalic acid... 

In this research, commercially available PHB/PET copolyester LCP, PEN and PET were mechanically blended to form the LC phase of the blends. The critical composition of PHB in the PEN and PET forming an LC ternary blend was investigated, and the miscibility and thermal behavior were studied using thermal analysis. The PHB content in the ternary blend was controlled by the amount of PHB/PET copolyester, as a high-molecular-weight PHB homopolyester does... 

To understand the nature of the microstructures that are present in these systems it is important to start by examining the role of the synthetic route in preparing these copolyesters. In the case of the PHBA/PET copolyester, this system presents a degree of complexity which is unusual. In the mid seventies, Jackson and Kuhfus reported that this system was random, but they did not comment on the possibility of compositional variations [2]. Fortunately, because of the modest solubility of this system, most of the confusion has recently been eliminated through detailed NMR studies [9]. Thus, it has been shown that the 60/40 PHBA/PET copolymers originally available from Tennessee Eastman actually consisted of two distinct compositions, namely 44/56 and 62/38 PHBA/PET (see Fig. 11). Furthermore, the soluble PET rich fraction ( 20%) was shown to be blocky while the insoluble PHBA rich fraction (80%) was more random (see Fig. 12). These observations can be explained from a... 

Fig. 12. PHBA dyad sequences for PHBA/PET copolyesters - experimental values, O -calculated values for totally random copolyesters...

Eastapak 9930 f [Eastman http //www.eastman.com] Eastapak 12440 [Eastman http //www.eastman.com] Eastapak 13213 [Eastman http //www.eastman.com] Eastapak PET 9921 [Eastman http //www.eastman.com] Eastapak PET Copolyester 13339 f [Eastman http //WWW. eastman. com]... 

Typically the viscosity of liquid crystalline fluids is highly dependent on shear rate over many orders of magnitude of y. This shear dependence of viscosity is illustrated by the data in Figure 7 for a 60 mole % PHB/PET copolyester. In this figure, data... 

PHB/PET copolyester are presented in Figure 11. Data is presented for several temperatures and we see that die swell increases with increasing temperature which is contrary to flexible chain isotropic polymers. Values of die swell based on a theory proposed by Tanner (15) and calculated from measured rheo . ggical properties have been compared with measured values of D./D. The... 

The transient shear flow experiments described in Figure 2 may provide the most insight into development of orientation and structure in LCP. We first look at stress growth at the start up of shear flow. In this experiment the stress build up at the start up of flow is monitored as a function of time. Some representative data for a 60 mole % PHB/PET copolyester are presented in Figure 16. At this particular temperature we observe two stress peaks. 

Insights into the chemical properties of polyesters have also been obtained using afm imaging as a tool. The dififusion/deposition of oligomers to the surface of PET copolyesters was demonstrated by imaging hard nodules on the polyester surfaces as a function of copolymer composition. The frequency of these hard nodules observed by afm correlated with the levels of oligomer that could be solvent-extracted from the copolymers (96). 

Zhang, 2009 PET/copolyester Unidirectional Fibre and film stacking 70 10 350 — ... 

Zhang, 2010 PET/copolyester skin Unidirectional Consolidation of coextruded yams 67 10.4 245 — —... 

Figure 4.6 Semilogarithmic plot of MFI versus T for HBA/PET copolyester using data from Refs. 42, 85, and 86. (Reprinted from Ref. 38 with kind permission from Elsevier Science S.A., Lausanne, Switzerland.)...

Bi-component fibres can be made from two variants of the same generic fibre (two types of polyester (PES), polyethylene terephthalate (PET), copolyester (coPES), polyacrylonitrile (PAN), polyamide (PA), polyethylene (PE) and polypropylene (PP)). The fibres can also be made from two different polymer compositions, e.g. PET/PA, PA/Spandex, etc. Different types of polymers, such as polyester, polyamides, polystyrene, polyurethane, polyolefines, polylactic acid, co-polyamides and soluble co-polyesters, have been used to spin bi-component fibres. 

Figure 9.6 DSC thermograms for compression-molded 60/40 HBA/PET copolyester specimens during (a) the heating cycle and (b) the cooling cycle at a rate of 20°C/min, where curve (1) is for the first heating or cooling cycle, curve (2) is for the second heating or coofing cycle, and curve (3) is for the third heating or cooling cycle.

Boyd and his co-workers extended their earlier studies of the PET homopolymeron HBA/PET copolyesters, being primarily interested... 

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