Polyethylene terephthalate PET

PET is resistant to dilute mineral acids, aliphatic hydrocarbons, aromatic hydrocarbons, ketones, and esters with limited resistance to hot water and washing soda. It is not resistant to alkaline and chlorinated hydrocarbons. PET has good resistance to UV degradation and weatherability. Refer to Table 2.29 for the compatibility of PET with selected corrodents. 

PET is used in the automotive industry for housings, racks, minor parts, and latch mechanisms. It can be painted to match metal body panels and has been used as fenders. 

PET is also used in water purification, food handling equipment, and 

PET is the polymer which has had one of the largest demand growth rates in recent years though to a major extent this is probably due to its use as glass substitute in bottle manufacture. PET may be reinforced with around 30% glass fibre and is one of the materials used in flexible printed circuits. In other applications where higher temperatures are likely to be encountered, flame retardant PET may be used. 

High-density polyethylene (HOPE) is typically used to produce push-in cable tie clips for insertion in pre-drilled holes in wood masonry and other materials. It is also used in the cable clips with small pre-fitted nails to enable cables to be clamped to masonry, wood and plaster surfaces. Polyethylene (PE) is also used as the material to mould bushings which insulate the rough cut conduit ends in flexible moulded cable and flexible metallic conduit. 

To meet the increasing demand for clear, thick PET film for use in flat panel displays (FPD) Teijin is to install new production facilities at its Gifu plant in Japan. This will come into operation in the third quarter of 2006. 

Polyethylene terephthalate (PET) is obtained by reacting purified terephthalic acid (PTA) and monoethylene glycol (MEG) and melting the reaction product to initiate the polycondensation. The molten polymer is then extruded, cut into chips and cooled. PET main use is in the soft drinks and water bottles, other applications include thick-walled containers for cosmetics and pharmaceuticals. 

Mass balance is presented in flash pyrolysis of PET at different temperatures in Table 10.19. Results of Williams [8] aud Kamiusky [11] show that the decompositiou of PET produces about the same quautities of gas aud liquid with a proportiou of solid arouud 10%. 

The compositiou of the gas phase is giveu iu Table 10.20. Accordiug to Williams [8], the gases contaiu carbou oxides (uearly 90%). These results are coufirmed by those of Kamiusky [11]. 

Iu the oils, beuzeue aud tolueue are the major compoueuts [11]. Beduas [39] fiuds aldehydes (formaldehyde aud acetaldehyde) as major compoueuts at 700°C. If the temperature rises 900°C, the amouut of acetaldehyde decreases aud carbou mouoxide becomes more importaut iu proportiou theu carbou dioxide [39]. This is explaiued by the decompositiou of acetaldehyde iu methaue aud carbou mouoxide. 

The results of the PET decompositiou iu slow pyrolysis are preseuted iu Table 10.21. 

As for flash pyrolysis, the proportiou of solid remaius importaut. The carbou couteut is estimated at 84.9% with 5.9% ash [16]. 

Polyesters can be either thermoplastics or thermosets, depending on their chemical composition. Polyethylene terephthalate (PET) is, by far, the most commonly used polyester. It has wide uses outside packaging as well, including polyester clothing and carpets. 

It is produced from para-xylene and ethylene. The p-xylene is converted into either dimethyl terephthalate or terephthalic acid, and the ethylene into ethylene glycol. These monomers are then polymerized by a condensation process, producing water as the byproduct molecule if terephthalic acid is used, and methanol if dimethyl terephthalate is used. Following the condensation polymerization, the molecular weight is increased by solid-stating, in which the dried and crystallized resin chips from the original polymerization are subjected to high temperature and vacuum. 

PET provides reasonably good oxygen and carbon dioxide barrier, which is improved by biaxial orientation. Properties of PET are summarized in Table 4.14. The largest single application of PET is in soft drink bottles, but tbe use of PET in non-soft-drink custom bottles has increased rapidly in the last few years, and continues to grow. In 2001, PET use in soft drink bottles totaled over 790 thousand tonnes, and PET use in other types of bottles and containers totaled over 827 thou- 

Films can be produced using chill roll casting. Injection blow molding and stretch blow molding are used to produce bottles. PET is also used in extrusion coating, and PET sheet is often thermoformed. 

Since oriented PET tends to deform when it is subjected to high temperatures, both film and bottles can be heat-set for improved stability. This allows use of PET for hot fill applications, for example. 

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Friedrich et al. also used XPS to investigate the mechanisms responsible for adhesion between evaporated metal films and polymer substrates [28]. They suggested that the products formed at the metal/polymer interface were determined by redox reactions occurring between the metal and polymer. In particular, it was shown that carbonyl groups in polymers could react with chromium. Thus, a layer of chromium that was 0.4 nm in thickness decreased the carbonyl content on the surface of polyethylene terephthalate (PET) or polymethylmethacrylate (PMMA) by about 8% but decreased the carbonyl content on the surface of polycarbonate (PC) by 77%. The C(ls) and 0(ls) spectra of PC before and after evaporation of chromium onto the surface are shown in Fig. 22. Before evaporation of chromium, the C(ls) spectra consisted of two components near 284.6 eV that were assigned to carbon atoms in the benzene rings and in the methyl groups. Two additional... 

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],... 

Polyethylene terephthalate (PET) an amorphous polymer is available in an engineering grade. It is extensively used in beverage bottles and films. 

PE. See polyethylene (PE) pendulum test method perfonnance of product design affecting predicting process and penneability of plastic PET. See polyethylene terephthalate (PET)... 

TABLE 2.11 Typical Properties of Unfilled Polyethylene terephthalate) (PET), Poly(trimethylene terephthalate) (PTT), and Poly(butylene terephthalate (PBT) Solid-State Polyester Resins... 

The effect of incorporating p-hydroxybenzoic acid (I) into the structures of various unsaturated polyesters synthesised from polyethylene terephthalate (PET) waste depolymerised by glycolysis at three different diethylene glycol (DEG) ratios with Mn acetate as transesterification catalyst, was studied. Copolyesters of PET modified using various I mole ratios showed excellent mechanical and chemical properties because of their liquid crystalline behaviour. The oligoesters obtained from the twelve modified unsaturated polyesters (MUP) were reacted with I and maleic anhydride, with variation of the I ratio with a view to determining the effect on mechanical... 

Polyethylene terephthalate (PET) is one of the most important commercial thermoplastic polyesters, which has been on the market since 1977 and is widely used in both industrial and household applications. Under specific conditions, plastics can be converted into their primary components for use in other chemical processes by chemical recycling. PET is a thermoplastic, and so recycling by chemical methods, which converts it into primary components, can be achieved. This study examines the optimal routes of the existing chemical methods. For chemical recycling, acidic hydrolysis is used and PET is converted into terephthalic acid (TPA) and... 

The performance properties of PEN present opportunities for replacement of rayon or polyamide in carcass construction. The use of PEN cord in these applications is currently being evaluated in both Asia and Europe. PEN has demonstrated acceptable flexural fatigue equivalent to polyethylene terephthalate (PET) and rayon. It has equivalent toughness to rayon, which is important for sidewall impact resistance. PEN s superior mechanical properties also afford opportunities to use less fiber in carcass construction enabling production of lighter-weight, more fuel-efficient tires. 

The most common polyester fiber is polyethylene terephthalate (PET), prepared from ethylene glycol and terephthalic acid. Acrylics... 

Terephthalic acid (p-TA or TA), a raw material for polyethylene terephthalate (PET) production, is one of the most important chemicals in petrochemical industry. Crude terephthalic acid (CTA), commonly produced by homogeneous liquid phase p-xylene oxidation, contains impurities such as 4-carboxybenzaldehyde (4-CBA, 2000-5000 ppm) and several colored polyaromatics that should be removed to obtain purified terephthalic acid (PTA). PTA is manufactured by hydropurification of CTA over carbon supported palladium catalyst (Pd/C) in current industry [1]. 

Example PET. Let us consider polyethylene terephthalate) (PET, C oHK(h n, Ppet=1-35 g/cm3) of tpET =2 mm thickness and an X-radiation wavelength X= 0.15418 nm (CuKa). We set up a table with one row for each chemical element and sum both the masses and the mass absorption coefficients multiplied by the masses. After normalization to the molecular mass of the PET monomer, 192.17 amu, we find (p/p)pet = 1291.97/192.17 cm2/g a value 6.72 cm2/g. Considering the density ppet we find for the linear absorption coefficient Ppet =... 

For semicrystalline isotropic materials a qualitative measure of crystallinity is directly obtained from the respective WAXS curve. Figure 8.2 demonstrates the phenomenon for polyethylene terephthalate) (PET). The curve in bold, solid line shows a WAXS curve with many reflections. The material is a PET with high crystallinity. The thin solid line at the bottom shows a compressed image of the corresponding scattering curve from a completely amorphous sample. Compared to the semicrystalline material it only shows two very broad peaks - the so-called first and second order of the amorphous halo. 

Direct evidence of nucleation during the induction period will also solve a recent argument within the field of polymer science as to whether the mechanism of the induction of polymers is related to the nucleation process or to the phase separation process (including spinodal decomposition). The latter was proposed by Imai et al. based on SAXS observation of so-called cold crystallization from the quenched glass (amorphous state) of polyethylene terephthalate) (PET) [19]. They supposed that the latter mechanism could be expanded to the usual melt crystallization, but there is no experimental support for the supposition. Our results will confirm that the nucleation mechanism is correct, in the case of melt crystallization. 

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. 

We previously reported that brominated aromatic phosphate esters are highly effective flame retardants for polymers containing oxygen such as polycarbonates and polyesters (9). Data were reported for use of this phosphate ester in polycarbonates, polyesters and blends. In some polymer systems, antimony oxide or sodium antimonate could be deleted. This paper is a continuation of that work and expands into polycarbonate alloys with polybutylene terephthalate (PBT), polyethylene terephthalate (PET) and acrylonitrile-butadiene-styrene (ABS). 

For example the condensation of ethylene glycol and terephthalic acid by the elimination of a molecule of water to yield polyethylene terephthalate (PET) as under ... 

POLYETHYLENE TEREPHTHALATE (PET) has been used for a long time only as raw material for the production of films and fibers. 

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... 

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