Polybutylene terephthalate resins

Terephthalic acid (TA) produced in a purified form (PTA) is used almost exclusively in the manufacture of polyethylene terephthalate (PET polyester) fibers. A smaller percentage of PTA is used for the manufacture of polyester films, polybutylene terephthalate resins and barrier resins for carbonated beverage bottles. Between 1994 and 1998, global PTA capacity increased by 62%, from lOmilfionto 17 million metric tons. Approximately 70% of worldwide PTA capacity is located in the Asia-Pacific region. ... 

Polyesters, which are a class of engineering thermoplastics, are found in a wide variety of applications including carbonated drink bottles, fibers for synthetic fabrics, thin films for photographic films and food packaging, injection molded automotive parts, and housings for small appliances. In this chapter, we svill explore the synthesis of this class of polymers. We will also look at the typical properties and end uses for the most common of these resins, polyethylene terephthalate and polybutylene terephthalate, which are commonly known as PET and PBT, respectively. 

Polyethylene terephthalate is most often extruded into films or fibers, or blow molded into bottles. Polybutylene terephthalate is primarily found in injection molded parts. Such parts are highly crystalline, which makes them opaque. Polybutylene terephthalate is often modified with glass fibers or impact modifiers. Table 24.1 contains applications by processing method and resin. 

Typically, polyester resins are used for high-end applications that require excellent electrical and thermal resistance. When dimensional stability under load is more critical, glass fibers are incorporated to increase the heat distortion temperature and the stiffness of the part. Examples of glass fiber reinforced parts include electrical housings, electrical adapters, computer components, telephone housings, and light bulb sockets. When impact modified, polybutylene terephthalate can be injection molded to make car bumpers. 

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). 

PTT is used in apparel, upholstery, specialty resins, and other applications in which properties such as softness, comfort stretch and recovery, dyeability, and easy care are desired. The properties of PTT surpass nylon and PET in fiber applications, and polybutylene terephthalate and PET in resin applications such as sealable closures, connectors, extrusion coatings, and blister packs (14). 

Most polymers fall in the class of translucent resins. These include acetal, polyamide, polybutylene terephthalate (PBT), polyethylene, and polypropylene as examples. There are very few neat polymers that are truly opaque (this depends on thickness as well). Liquid crystal polymer (LCP) is an example of a typically opaque polymer. It is theorized that these semicrystalline and crystalline resins will scatter some portion of incident light due to spherulitic crystal structure and the amorphous-crystalline region interfaces themselves. 

Hahgenated polymers, both brominated and chlorinated, have been developed to yield better polymer compatibility, improve physical properties, and long-term-aging characteristics in many thermoplastic resins, particularly the high-performance engineering thermoplastics, such as nylon, polybutylene terephthalate (PBT) and polyethylene terephthalate (PET). These materials still use antimony oxide as a synergist to achieve the desired flame resistance (31). 

Engineering plastics are those to which standard metal engineering equations can be applied they are capable of sustaining high loads and stresses and are machinable and dimensionally stable. They are used in construction, as machine parts, automobile components, etc. Among the more important are nylon, acetals, polycarbonates, ABS resins, PPO/styrene, and polybutylene terephthalate. 

Linear aliphatic chols are widely used as raw materials for polymers. Polymers synthesized from even-carbon diols tend to show excellent polymer properties. 1,4-Butanediol is very important as raw material for various polymers such as urethanes and polybutylene terephthalate (PBT), which is an engineering plastic. Since Celanese Corporation described a PBT resin in 1970, the demand for PBT resin, which is mainly used for automotive, electrical, and electronic equipment parts, has been expanding rapidly [1]. THF is also a major 1,4-butanediol derivative as a raw material for poly(tetramethylene ether) glycol used for artificial leather and elastic fibers in addition to being a high-performance solvent. Significant growth in demand for these 1,4-butanediol derivatives is expected in Asia, primarily in China. 

Plastics find extensive use in several areas of fiber optic cables. Buffer tubes, usually extruded from high-performance plastics such as fluoropolymers, nylon, acetal resins, or polybutylene terephthalate (PBT) are used for sheathing optical fibers. A blend o PVC and ethylene vinyl acetate (EVA) polymer, such as Pantalast 1162 of Pantasote Incorporated, does not require a plasticizer, which helps the material maintain stability when in contact with water-proofing materials. PVC and elastomer blends, Carloy 6190 and 6178, of Cary Chemicals are also used for fiber optic applications (Stiffening rods for fiber optics are either pultruded epoxy and glass or steel. Around these is the outer jacketing, which is similar to conventional cable.)... 

Unsaturated polyesters are produced in the form of dissolved resins in polymerizable monomers (usually styrene). They are also known in the form of molding resins or as hardened products. One should distinguish between them and the saturated aliphatic and aromatic polyesters. Among the latter are polyethylene terephthalate and polybutylene terephthalate. 

PDM-0421, PDM-0821, PDM-1922. See Phenylmethyl polysiloxane PDM-704, PDM-7050. See Tetramethyl tetraphenyl trisiloxane PDMS. See Polydimethylsiloxane PDX-84367. See Polyetherimide resin PDX-84368. See Polycarbonate PDX-84369. See Polybutylene terephthalate PE-25. See Polyethylene, medium density PE. See Pentaerythritol Polyethylene PEA P-PEA. See Phenethyl alcohol Peach aldehyde. See y-Undecalactone Peach kernel extract. See Peach (Prunus persica) kernel extract... 

Poly (tetramethylene terephthalate). See Polybutylene terephthalate Polytex 10. See Stearamide DIBA-stearate Poly-Tex 950. See Hydroxypropyl methacrylate Poly-Tex 975, Poly-Tex 9008. See Acrylic resin Polythene. See Polyethylene PolyTHF 25a, PolyTHF 650. See Polytetramethylene ether glycol PolyTHF 100a, PolyTHF 2000. See Polyether-polycarbonate diol... 

See Polyester elastomer, thermoplastic Riteflex 677. See Polybutylene terephthalate Riteflex BP 8929, Riteflex BP 9056, Riteflex BP 9057, Riteflex BP 9086, Riteflex BPX 9056. See Polyester elastomer, thermoplastic Ritoleth 2. See Oleth-2 Ritoleth 5. See Oleth-5 Ritoleth 10. SeeOleth-10 Ritoleth 20. See Oleth-20 Rit-O-Lite MHP-S. See Formaldehyde/toluenesulfonamide polymer Ritox 35. See Laureth-23 Ritox 52. See PEG-40 stearate Ritox 53. See PEG-50 stearate Ritox 59. See PEG-100 stearate Ritox 721. See Steareth-21 RIX 80482. See Phenolic resin Rizolex. See Tolclofos-methyl / L-60 RL-68, RL-90. See Titanium dioxide RMDI. See Methylene bis (4-... 

Polyacrylamidomethylpropane sulfonic acid Polyacrylic acid Polybutylene terephthalate Polydimethylaminoethyl methacrylate Polyester resin, thermoplastic Polyethylacrylate Polyethylene Polyethylene terephthalate Polyglucuronic acid Polyisobutene Polymethacrylamidopropyl trimonium chloride Polymethyl acrylate Polymethyl methacrylate Polyoxyisobutylene/methylene urea copolymer Polypropylene Polypropylene, oxidized Polyquaternium-1 Polyquaternium-2 Polyquaternium-4 Polyquaternium-5 Polyquaternium-6 Polyquaternium-7... 

In DuPont Hytrel polyester TPEs, the resin is a block copolymer. The hard phase is polybutylene terephthalate (PBT). The soft segments are long-chain polyether glycols. 

The electrical properties of LCPs and polybutylene terephthalate (PBT) resins are comparable although LCPs offer at least a few advantages over PBT in electric applications, i.e., low mold shrinkage, fast cycling time, ease of molding thin parts, low moisture regain, and excellent chemical and mechanical properties. 

The thermoplastic polyesters (PEST) are dominated by two resins polyethylene terephthalate (PET) and polybutylene terephthalate (PBT). There are similarities between ABS/PA and ABS/PEST blends. 

Terephthalate polyester ter- o(f)- tha lat, pa-le- es-tor n. Any polymeric ester of ter-ephthalic acid (1,4-benzene dicarboxylic acid), but in particular the three commercially important thermoplastic resins, polyethylene terephthalate, polybutylene terephthalate, and poly-cyclohexylene dimethylene terephthalate. 

Thermoplastic polyester n. Any of a class of linear terephthalate polyesters that are true thermoplastics. Commercially important are polyethylene, terephthalate, polybutylene terephthalate, and poly-cycloxexylenedimethylene terephthalate. USA sales of these resins in 1992 totaled 1.24 Tg (1.37 X 10 tons). 

The temperature curve of the extruder depends on the viscosity of the polymer. Being more viscous than nylon or polybutylene terephthalate (PBT), polypropylene resin heats up much faster than the latter two in the compression zone (131). The introduction of glass fibers downstream reduces the melt temperature by 5°C. The viscosity of the compound increases once glass fibers are incorpo-... 

The most common thermosetting laminating resins are phenolics, melamines, epoxies, polyesters, silicones, and polyimides. Thermoplastic resins used in making laminates include polysulfone, polyphenylene sulfide, polyetheretherketone, polyamide-imide, polybutylene terephthalate, nylon 6, and polypropylene. 

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