Poly Tetramethylene Terephthalate

T nterest in polyether-ester block copolymers that are both thermoplastic - and elastomeric continues at a sustained pace (1-9). Most of the recent communications have dealt with the tetramethylene terephthalate/ poly(tetramethylene ether) terephthalate copolymers which are continuing to find increased use in commercial applications requiring thermoplastic elastomers with superior properties. 

Poly(tetrafluoroethylene) (ASTM DIN ISO lUPAC NS) Poly(tetramethylene terephthalate) = poly(butadiene terephthalate) see also PBTP... 

This polymer, with a very high melting point (265°C) and a good resistance to hydrolysis, has since been widely studied because of its commercial applications as a fiber (10). Recently, another polymer of the series, poly(tetramethylene terephthalate) = poly (butylene terephthalate) = 4GT, has been used as a thermoplastic resin (11)... 

In this review the definition of orientation and orientation functions or orientation averages will be considered in detail. This will be followed by a comprehensive account of the information which can be obtained by three spectroscopic techniques, infra-red and Raman spectroscopy and broad line nuclear magnetic resonance. The use of polarized fluorescence will not be discussed here, but is the subject of a contemporary review article by the author and J. H. Nobbs 1. The present review will be completed by consideration of the information which has been obtained on the development of molecular orientation in polyethylene terephthalate and poly(tetramethylene terephthalate) where there are also clearly defined changes in the conformation of the molecule. In this paper, particular attention will be given to the characterization of biaxially oriented films. Previous reviews of this subject have been given by the author and his colleagues, but have been concerned with discussion of results for uniaxially oriented systems only2,3). 

These materials are segmented copolyether esters formed by the melt transesterification of dimethyl terephthalate, poly(tetramethylene ether) glycol and 1,4-butane diol. As with the thermoplastic polyurethanes, one can describe a hard segment and a soft segment, the hard segments forming crystalline areas which act as pseudocrosslinks . 

PTT is made by the melt polycondensation of PDO with either terephthalic acid or dimethyl terephthalate. The chemical structure is shown in Figure 11.1. It is also called 3GT in the polyester industry, with G and T standing for glycol and terephthalate, respectively. The number preceding G stands for the number of methylene units in the glycol moiety. In the literature, polypropylene terephthalate) (PPT) is also frequently encountered however, this nomenclature does not distinguish whether the glycol moiety is made from a branched 1,2-propanediol or a linear 1,3-propanediol. Another abbreviation sometimes used in the literature is PTMT, which could be confused with poly(tetramethylene terephthalate),... 

Figure 12.4 Structures of polyesters with longer aliphatic chains (a) poly(tri-methylene terephthalate) (PTT) (b) poly(tetramethylene terephthalate) (PBT)...

Copoly(ether ester)s consisting of short-chain crystalline segments of PBT and amorphous poly(ether ester) of poly(tetramethylene terephthalate) exhibit a two-phase structure and can be used for the production of high-impact-strength engineering plastics. These very interesting materials with their outstanding properties understandably require stabilization to heat and UV exposure [45],... 

A Comparison of Published Structures of Poly(tetramethylene terephthalate)... 

This is illustrated by the case of poly (tetramethylene terephthalate) (4GT). Three independent determinations have been made of the crystalline structure of the cx-phase of this material. (1,2,3). The conformation angles are given in Table I (see Figure 1 for key) from which it will be seen that they all... 

Figure 9 shows the dynamic mechanical spectra of a series of poly-(tetramethylene oxide) /poly (tetramethylene terephthalate) (PTMO/ PTMT) segmented copolymers (67). These materials reveal only one Tg and one Tm analogous to semicrystalline thermoplastics. The magnitude of both transition temperatures shifts progressively higher with increasing... 

Studies have been conducted on poly (tetramethylene oxide )-poly-(tetramethylene terephthalate) -segmented copolymers that are identical in all respects except for their crystalline superstructure (66,67,68). Four types of structures—type I, II, and III spherulites (with their major optical axis at an angle of 45°, 90°, and 0° to the radial direction, respectively), and no spherulitic structure—were produced in one segmented polymer by varying the sample-preparation method. Figures 10 and 11 show the stress-strain and IR dichroism results for these samples, respec-... 

Part I of this series explored the structure-property relationships of tetramethylene terephthalate/polyether terephthalate copolymers as a function of variations in the chemical structure, molecular weight, and concentration of the polyether units (10). Of the polyether monomers tested, poly (tetramethylene ether) glycol of molecular weight approximately 1000 was found to provide copolymers having the best overall combination of physical properties and ease of synthesis. 

Copolymer compositions are expressed as weight percentages of the ester units with the remainder being polyether-ester units. For instance, 40% tetramethylene terephthalate/PTME terephthalate copolymer represents a block copolymer containing 40 wt % of tetramethylene terephthalate units and by difference 60 wt % of poly(tetramethylene ether) terephthalate units. 

Poly(methyl acrylate) Poly(methyl methacrylate) Polyacrylonitrile Polymethacrylonitrile Polybutadiene Polyisoprene Polychloroprene Poly(methylene oxide) Poly(ethylene oxide) Poly(tetramethylene oxide) Poly(propylene oxide) Poly(hexamethylene succinate) Poly(hexamethylene sebacate) Poly(ethylene terephthalate) Nylon 6 Polycarbonate... 

PB PBI PBMA PBO PBT(H) PBTP PC PCHMA PCTFE PDAP PDMS PE PEHD PELD PEMD PEC PEEK PEG PEI PEK PEN PEO PES PET PF PI PIB PMA PMMA PMI PMP POB POM PP PPE PPP PPPE PPQ PPS PPSU PS PSU PTFE PTMT PU PUR Poly(n.butylene) Poly(benzimidazole) Poly(n.butyl methacrylate) Poly(benzoxazole) Poly(benzthiazole) Poly(butylene glycol terephthalate) Polycarbonate Poly(cyclohexyl methacrylate) Poly(chloro-trifluoro ethylene) Poly(diallyl phthalate) Poly(dimethyl siloxane) Polyethylene High density polyethylene Low density polyethylene Medium density polyethylene Chlorinated polyethylene Poly-ether-ether ketone poly(ethylene glycol) Poly-ether-imide Poly-ether ketone Poly(ethylene-2,6-naphthalene dicarboxylate) Poly(ethylene oxide) Poly-ether sulfone Poly(ethylene terephthalate) Phenol formaldehyde resin Polyimide Polyisobutylene Poly(methyl acrylate) Poly(methyl methacrylate) Poly(methacryl imide) Poly(methylpentene) Poly(hydroxy-benzoate) Polyoxymethylene = polyacetal = polyformaldehyde Polypropylene Poly (2,6-dimethyl-l,4-phenylene ether) = Poly(phenylene oxide) Polyp araphenylene Poly(2,6-diphenyl-l,4-phenylene ether) Poly(phenyl quinoxaline) Polyphenylene sulfide, polysulfide Polyphenylene sulfone Polystyrene Polysulfone Poly(tetrafluoroethylene) Poly(tetramethylene terephthalate) Polyurethane Polyurethane rubber... 

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