Polyesters polyethylene terephthalate PET

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... 

Poly(trimethylene terephthalate) (PTT) is a newly commercialized aromatic polyester. Although available in commercial quantities only as recently as 1998 [1], it was one of the three high-melting-point aromatic polyesters first synthesized by Whinfield and Dickson [2] nearly 60 years ago. Two of these polyesters, polyethylene terephthalate) (PET) and poly(butylene terephthalate) (PBT), have become well-established high-volume polymers. PTT has remained an obscure polymer until recent times because one of its monomers, 1,3-propanediol (PDO), was not readily available. PDO was sold as a small-volume fine chemical at more than 10/lb., and was therefore not suitable as a raw material for commercial polymers. 

Graphite is an excellent but expensive reinforcement for plastics. Aramid (aromatic polyamide), polyester (polyethylene terephthalate PET), and boron filaments are also used as reinforcements for polymers. 

Acetic acid is used in the manufacture of a wide variety of products including adhesives, polyester fibres, plastics, paints, resins and solvents. About 40% of the acetic acid made industrially is used in the manufacture of vinyl acetate monomer for the plastics industry other large uses are to make cellulose acetate, a variety of acetate esters that are used as solvents, as well as monochloracetic acid, a pesticide. Acetic acid is also used as a solvent for the oxidation of p-xylene to terephthalic acid, a precursor to the important polyester, polyethylene terephthalate (PET). A minor, but important use is as non-brewed condiment, a vinegar substitute widely used in British fish and chip shops this is made using food-grade industrial acetic acid and is less expensive than fermentation vinegar. 

Saturated Polyesters - Polyethylene Terephthalate (PET-S) and Polybutylene Terephthalate (PBT-S)... 

The second of the two basic polymerization processes that results in linear chain molecules is the condensation reaction where, e.g., in the case of formation of the polyester, polyethylene terephthalate (PET), as shown in Fig. 2.3, two separate monomers, ethylene glycol and terephthalic acid, react and give off a reaction product, H2O, in a systematic process that results in a chain polymer. 

Polyesters UV absorbers have been used as efficient stabilizers of the linear polyesters, polyethylene terephthalate (PET) and polybutylene terephthalate (PBT) as well as for improving the lightfasmess of dyes in polyester fibers during outdoor exposure. Effective stabilization of high-molecular-weight PET fibers by a UV absorber was shown [106] to depend on the level of uptake and its uniform distribution throughout the fiber cross section. A benzophenone-type stabilizer provided considerably better protection than the benzotriazole- and benzotriazine-type stabilizers because it diffused throughout the fiber whereas the other two... 

Saturated polyester, polyethylene terephthalate (PET) 15-25 Appliance panels automotive body panels power tool housings Improved strength Improved heat deformation temperature Improved dimensional stability... 

Identification of plastics can be as simple as finding the resin identification code (typically on the bottom of the component) or as complex as separating the base resin from the filler, reinforcements, and colorants to analyze via infrared (IR) spectroscopy. The resin identification codes developed by the Society of Plastics Industry in 1998 are shown in Table 1.5. Despite the desire of many individuals to recycle, many communities recycle often only recycle plastics polyester (polyethylene terephthalate (PET)) and high-density polyethylene (HDPE). In fact, local recycling companies in the United States will often bury plastics in a landfill, either with the rest of the waste or in separate locations, ostensibly to mine at a later date. Collected recyclables are also shipped from the United States as baled... 

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

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). 

Claims of perpetual motion create moments of mirth and consternation for those knowledgeable in the laws of thermodynamics. Yet, is it only hyperbole when a responsible journal such as the European Plastics News [1] proclaims that depolymerization of polyethylene terephthalate (PET) can be repeated indefinitely The second law of thermodynamics brings us back to reality. The depolymerization of PET does not operate at 100% yields, but does offer the opportunity for near-stoichiometric recovery of the monomers used to make the polyester. With high yields of potentially valuable monomers, the commercial potential for polyester depolymerization to regain feedstocks must be considered. 

The workhorse polyester is polyethylene terephthalate) (PET) which is used for packaging, stretch-blown bottles and for the production of fibre for textile products. The mechanism, catalysis and kinetics of PET polymerization are described in Chapter 2. Newer polymerization techniques involving the ring-opening of cyclic polyester oligomers is providing another route to the production of commercial thermoplastic polyesters (see Chapter 3). 

The most important polyester is polyethylene terephthalate (PET), which has mariy uses, from fabrics to milk bottles. The polymerization reaction between ethylene glycol (EG) and terephthahc acid (TPA),... 

Linear polyesters, such as polyethylene terephthalate (PET, Dacron, Mylar), are heteropolymers with carbon and oxygen atoms in the polymer chain ... 

PBDEs are used in different resins, polymers, and substrates at levels ranging from 5 to 30% by weight (EU 2001). Plastic materials that utilize PBDEs as flame retardants include ABS polyacrylonitrile (PAN) polyamide(PA) polybutylene terephthalate (PBT) polyethylene (PE) cross-linked polyethylene (XPE) polyethylene terephthalate (PET) polypropylene (PP) polystyrene (PS) high-impact polystyrene (HIPS) polyvinyl chloride (PVC) polyurethane (PUR) and unsaturated polyester (UPE). These polymers and examples of their final products are summarized inTable 5-2 (Hardy 2002 WHO 1994a). 

The largest commercial use of ethylene glycol is its reaction with dicarboxylic acids to form linear polyesters. Polyethylene terephthalate) [25038-59-9] (PET) is produced by esterification of terephthalic acid [100-21 -0] (1) to form bishydroxyethyl terephthalate [959-26-2] (BHET) (2). BHET polymerizes in a transesterification reaction catalyzed by antimony oxide to form PET (3). 

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