Polyethylene terephthalate development

IntegRex A process for making polyethylene terephthalate, developed by Eastman Chemical, announced in 2004. It integrates the PX-PTA process with the PTA-PET process. It uses an aqueous solution of tere-phthalic acid instead of the solid acid. Johnson Matthey has developed a special catalyst for it. The first plant was built in S. Carolina in 2006. There was a patent dispute between Eastman Chemical and Wellman regarding the resin product, trade named ParaStar. The process was sold to DAK Americas in 2011 who licensed it to Alpek in 2013. 

In studying contact between films of polyethylene (PE) and polyethylene terephthalate (PET) bonded to quartz cylinders, they observed an increase in adhesion energy with contact time for a PE/PE pair, but not for PE/PET or PET/PET combinations. They interpreted this as evidence for the development of nanoscale roughness due to the interdiffusion of chains across the PE/PE interface [84],... 

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). 

In this review recent theoretical developments which enable quantitative measures of molecular orientation in polymers to be obtained from infra-red and Raman spectroscopy and nuclear magnetic resonance have been discussed in some detail. Although this is clearly a subject of some complexity, it has been possible to show that the systematic application of these techniques to polyethylene terephthalate and polytetramethylene terephthalate can provide unique information of considerable value. This information can be used on the one hand to gain an understanding of the mechanisms of deformation, and on the other to provide a structural understanding of physical properties, especially mechanical properties. 

The above-mentioned method is effective in identifying the molecules of detected ions. However, because PVDF film is not permeable to light, it is difficult to observe tissue sections. To resolve this problem, we developed a method to fix tissue sections on transparent film, and then performed MS on those sections.6 We used a conductive film because we expected the ionization efficiency would increase when the electric charge accumulation on the sample was reduced. The film used for this purpose was a polyethylene terephthalate (PET) film with a thickness of 75-125 pm, having a 5 15-nm-thick layer of evaporated oxidation indium tin (ITO) upon it (ITO film). This film is used in touch-panel displays because of its high transparency and superior conductivity. We used it to perform MS/MS for tissue sections and succeeded in identifying multiple proteins from mass spectra.6 Therefore, the further development of this method will enable the application of the mass-microscopic method to observe tissue by optical microscope and to perform tandem mass spectrometry (MSn) at the observation part, simultaneously, enabling the identification of molecules included the part. 

In 1953, E. F. Izard of du Pont was awarded the Schoellkopf Medal of the American Chemical Society. The report [36] of this award states that work on the development of a hydrolytically stable polyester was started by Dr Izard in 1944, and it led in a comparatively short time to the discovery of polyethylene terephthalate . The report recognises that polyethylene terephthalate was earlier discovered independently in England by J. R. Whinfield . Izard himself says [37] that the duPont research programme led immediately to the discovery of poly(ethylene terephthalate) (PET), which suggests that detailed information from ICI about the structure of the new fibre had not yet reached him by that time. 

PBT resin has been reviewed in many articles, often as part of a larger review of polyesters [1-3], A recent article provides an historic account of polyester development as an alternative to nylon fibers [4], while the review of Kirsch and Williams in 1994 gives a business perspective on polyesters [5], However, an understanding of PBT in the context of the more common polyester polyethylene terephthalate) (PET) is often overlooked. PET dominates the large volume arenas... 

Polyethylene terephthalate) (PET) has become a major synthetic polymer during the past forty years. Significant commercial markets [1] have been developed for its application in textile and industrial fibers, films, and foamed articles, containers for carbonated beverages, water and other liquids, and thermoformed applications (e.g. dual ovenable containers). 

In addition to the established large volume products already mentioned, other plastic materials are known to be under study or have been introduced so recently that their markets have not been fully developed. It seems certain that products such as polyethylene terephthalate and polyacrylonitrile fibers will attain large volume production. A new type of resin that has appeared very recently is Shell Chemical Co. s Epon series (32), a group of polymers of various molecular weight ranges which are produced from phenol, acetone, and epichlorohydrin. 

By the mid 1970s, Tennessee Eastman also announced development of a copolyester consisting of 60/40 PHBA/polyethylene terephthalate (PET) by direction reaction of acetoxybenozic acid with PET in the melt [2], This system had the advantage of lower costs, but its use temperature was limited to 90 °C which is just above its Tg. In the early 1980s, researchers at Celanese reported... 

Akzo has been instrumental in developing a new process for the stereospecific synthesis of trans- 1,4-cyclohexane diisocyanate [7517-76-2] (21). This process, based on the conversion of polyethylene terephthalate) [25038-59-9], circumvents the elaborate fractional crystallization procedures required for the existing -phenylenediamine [108-45-2] approaches. The synthesis starts with polyethylene terephthalate) (PET) (32) or phthalic acid, which is converted to the dimethyl ester and hydrogenated to yield the cyclohexane-based diester (33). Subsequent reaction of the ester with ammonia provides the... 

Oxirane/cyclic acid anhydride alternating copolymers of controlled molecular weight with a narrow molecular weight distribution were found by Aida et al. [188,189] to be formed under mild conditions when copolymerising ethylene oxide and phthalic anhydride in the presence of the (tpp)AlCl-quater-nary phosphonium salt catalyst system. The copolymerisation carried out with (tpp)AlCl alone proceeded very slowly, and the product was not polyethylene terephthalate) but contained ether linkages in considerable amount. The development of the living character and the tendency towards alternation of the copolymerisation when using the aluminium porphyrin catalyst, coupled with a quaternary salt, have been postulated [188,189] to be due to the formation of... 

Whereas UL 94 delivers only a classification based on a pass-and-fail system, LOI can be used to rank and compare the flammability behavior of different materials. In Figure 15.2 the increasing LOI values are presented for different polymers as an example POM = poly(oxymethylene), PEO = poly(ethyl oxide), PMMA = poly(methyl methacrylate), PE = polyethylene), PP, ABS, PS, PET = polyethylene terephthalate), PVA = poly(vinyl alcohol), PBT, PA = poly(amide), PC, PPO = poly(phenylene oxide), PSU, PEEK = poly(ether ether ketone), PAEK = poly(aryl ether ketone), PES, PBI = poly(benzimidazole), PEI = poly(ether imide), PVC = poly(vinyl chloride), PBO = poly(aryl ether benzoxazole), PTFE. The higher the LOI, the better is the intrinsic flame retardancy. Apart from rigid PVC, nearly all commodity and technical polymers are flammable. Only a few high-performance polymers are self-extinguishing. Table 15.1 shows an example of how the LOI is used in the development of flame-retarded materials. The flame retardant red phosphorus (Pred) increases... 

Suloff, E. C. (2001). Modeling the adsorption of aldehydes and ketones to novel polyethylene terephthalate) blends by inverse gas chromatography to develop an improved polymer for food packaging. Ph.D. Dissertation, Virginia Tech, Blacksburg. 

In this study, Raman spectroscopy and pattern-recognition techniques were used to develop a potential method to differentiate common household plastics by type [87-89], which is crucial to ensure the economic viability of recycling. The test data consisted of 188 Raman spectra of six common household plastics high-density polyethylene (HDPE), low-density polyethylene (LDPE), polyethylene terephthalate (PET), polypropylene (PP), polystyrene (PS), and polyvinylchloride... 

Polyethylene terephthalate cannot be solvent-cemented or heat-welded. Adhesives are the prime way of joining PET to itself and to other substrates. Only solvent cleaning of PET surfaces is recommended as a surface treatment. The linear film of polyethylene terephthalate (Mylar) provides a surface that can be pretreated by alkaline etching or plasma for maximum adhesion, but often a special treatment such as this is not necessary. An adhesive for linear polyester has been developed from a partially amidized acid from a secondary amine, reacted at less than stoichiometric with a DGEB A epoxy resin, and cured with a dihydrazide.72... 

For conventional technical applications aromatic polyesters such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT) are widely used. But these polymers are biologically inert and thus not directly applicable as biodegradable plastics. Combining both the excellent material properties of aromatic polyesters and the potential biodegradability of aliphatic polyesters has led to the development of a number of commercially available aliphatic-aromatic co-polyesters over the last decade or so. 

South Korean company SK Chemicals produces SKYGREEN polybutylene succinate (PBS) thermoplastics based on aliphatic polyester and aliphatic/aromatic co-polyesters that were developed from SK Chemicals polyethylene terephthalate (PET) technology. SKYGREEN BDP products offer LDPE-like properties. They are used in films, disposable cutlery, food trays, hairbrush handles and paper coatings. Aliphatic versions biodegrade more rapidly and offer better processing and tensile properties than the aromatic-aliphatic grades, which cost less. 

The recycling of plastics also contributes to energy efficiency. Soft drink bottles made from polyethylene terephthalate reached a recycling rate of 41% in the U.S. in 1995 (19). Recycling is becoming widespread, and many studies are in progress to develop new and improved recycling practices. 

IntegRex An integrated process for making polyethylene terephthalate from p-xylene. Developed by Eastman Chemical, announced in 2004, and first commercialized in Columbia, SC, in 2007. A larger plant was planned for 2009. 

SSP [Solid State Polymerization] Also called UOP Sinco SSP. A process for making articles from PET (polyethylene terephthalate) and related polymers. The key step is controlled crystallization of the polymer under optimum conditions. Developed jointly by UOP (United States) and Sinco (Italy) and widely adopted since 1986. 

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