Polyterephthalate

The copolyester was first marketed as Tenite Polyterephthalate 7DRO but is now sold as Kodar PETG. 

Figure 11.9 Dynamic mechanical storage ( ) and loss ( ") moduli of isotropic PTT at 11 Hz showing the three relaxations [61]. From Dynamic mechanical relaxations of polyterephthalates based on trimethylene glycols, Gonzalez, C. C., Perena, J. M. and Bello, A., J. Polym. Sci., Polym. Phys. Ed., 26,1397-1408 (1988), Copyright (1988 John Wiley Sons, Inc.). Reprinted by permission of John Wiley Sons, Inc...

In 1984 Thiem et al. [50, 51] prepared polyterephthalates 64 of low molecular weight by melting condensation of terephthalic acid dichloride with 1,4 3,6-dianhydrohexitols. With labile isosorbide (1) polymers of cross-linked character were obtained. Later, Storbeck et al. [52] reinvestigated these polyterephthalates. The reaction conditions were optimized, and pyridine was found to be the most useful acceptor of hydrogen chloride. 

In this study, polyesters [XII] having syringyl-type biphenyl units were synthesized from 4,4 -dihydroxy-3,3, 5,5 -tetramethoxybiphenyl (XI) which was prepared from 2,6-dimethoxyphenol (11). As shown in Scheme 6, poly esterification of XI with terephthaloyl, isophthaloyl and sebacoyl chloride were carried out by the low temperature solution polycondensation and by the interfacial polycondensation. The polyterephthalate with jjinh = 1.42 dl/g was obtained by the interfacial poly condensation. The polyisophtha-late with f7 nh = 0.73 dl/g and the polysebacate with Jj nh = 0.43 dl/g were obtained by the low temperature solution polycondensation. 

Thermal properties of the polyesters obtained were studied by TG and DSC. The starting temperature of decomposition (Tfrom Table III, Tpolymer measured in air is lower than that measured in nitrogen. T[Pg.219]

A DSC curve of polyterephthalate obtained in the temperature range between room temperature and that just below Tphase transition. However, an X-ray diffractogram of this polymer showed a crystalline pattern. Accordingly, it was considered that the molecular chain of... 

Action of terephthaloyl chloride on an /V-(si IyI methyl jpyridine ylid leads to alkylation with the formation of a polyterephthalic siloxane material.290... 

PAn has been integrated into other structures (polyethylene, polyterephthalate, polyester, and polystyrene) by soaking in monomer solutions and then exposing to acidic oxidant (FeCl3) solutions 41 Results suggest that the polymers were swollen by the aniline monomer and that polymerization occurred within these swollen media to produce dispersed PAn granules. Conductivities on the order of 10 1 S cm-1 were obtained. 

A relationship between the polymer structure and its flammability was related to unsaturation for co-polyterephthalates and co-polycarbonates [Quinn, 1977]. This work is an excellent illustration of the importance of condensed-phase pyrolytic mechanisms upon polymer flammability. 

Uses Flame retardant for ABS, PE, PP, PS, PU rigid and flexible foam, EVA, TPE, TPR, rubber, acrylics, polyterephthalate, intumescent latex and solv.-based paints, intumescent mastic, caulks, and putties, building materials (wall coverings, ceiling tiles, roofing prods., wall panels, wood chip board)... 

Thiem, J. and Lueders, H. (1984) Synthesis of polyterephthalates derived from dianhydrohexitols. Polymer Bulletin (Berlin), 11 (4), 365-369. 

Polyterephthalates. The molecular motion and their connection to the thermal parameters for the three most common members of the homologous series of polyterephthalates is summarized in Fig. 6.40. The number of vibrations and the derived 0-temperatures allows the calculation of a vibrational heat capacity of the solid state, as outlined in Sect. 2.3.7. The changes within the 0-temperatures are practically within the error hmit. The specific heat capacities of the polyterephthalates are, as a result, also almost the same. The transition parameters are extrapolated to the equilibrium crystals and the fuUy amorphous glasses. Their values show regular changes with chemical stracture. All thermal properties are next related to the vibrational baselines computed from the parameters of Fig. 6.40. 

Poly(butylene terephthalate), PBT, is the next member of the homologous series of polyterephthalates with its thermodynamic properties listed in Fig. 6.40. Figine 6.45 presents the crystallinity for a semicrystalline, melt-crystallized PBT sample, calculated with the method of Fig. 4.80, Eq. (3). Below the glass transition, the crystallinity reaches 36.2%. With this crystallinity function, the expected heat capacity without latent heat effects is given in Fig. 6.46. 

An alternative approach to develop cross-linked photoresponsive polymers for use as photochromic coatings (47) relies on the quatemization of the amine groups of IV-methyldiethanolamine polyterephthalate by a mixture of bis(2,5-dimethyl-4-chloromethyl-3-thienyl)-l,3-dioxol-2-one and p- or m-xylylene dichloride in different ratios [92]. The coatings obtained using this method exhibit photochromic behavior, although some examples of the ring-closed forms did bleach back to the ring-open isomers when stored in the dark. 

Mylar Mylar is a tradename for a polyterephthalate film produced by Du Pont. It is manufactured from the polyester of ethylene glycol and terephthalic acid (dimethyl terephathalate). Mylar films are commonly used in the electrical/ electronic industries for their excellent electrical properties and also as high-strength film for structural applications. 

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