Polybutylene Terephthalate PBT

PBT is also known as a thermoplastic polyester. These thermoplastic polyesters are highly crystalline with a melting point of approximately 430°F (221°C). It has a structural formula as follows  

PBT exhibits good chemical resistance, in general, 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 chlorinated hydrocarbons and alkalies. 

PBT has good weatherability and is resistant to UV degradation. Refer to Table 2.40 for the compatibility of PBT with selected corrodents. 

The unreinforced resins are used in housings that require excellent impact in moving parts such as gears, bearings, pulleys, and writing instruments. Flame retardant formulations find application as television, radio, electronics, business machines, and pump components. 

Reinforced resins find application in the automotive, electrical, electronic, and general industrial areas. 

Polybutylene Terephthalate (PBT) Solvents recommended by General Electric for their VALOX thermoplastic polyester are (11)  

The solvent is brushed on the mating surface and dried under pressure. These solvents are toxic and should be applied only in areas of positive ventilation. 

Polybutylene terephthalate (PBT) is a semi-crystalline saturated polyester, which has been produced since 1942. PBT is made by the polycondensation of terephthalic acid or dimethyl terephthalate with 1,4-butanediol in the presence of a catalyst. Terephthalic acid, dimethyl terephthalate and 1,4-butanediol are derived from petrochemicals such as xylene and acetylene. The polymer is noted for high stiffness and strength, high resistance to heat, low water absorption and high dimensional stability. It has moderate chemical resistance and low resistance to strong acids and bases. 

There are a number of different grades and types of PBT resins and compounds available. The most 

PBT is also blended with polycarbonate to give special low warpage grades with high impact strength even at low temperatures. The volume of PC/PBT blends is included in the market definition of PBT. 

Elastic modulus (MPa) (tensile with 0.2% water content) 1932-3002 8970-10005 9660 

Automotive is the largest market for PBT. Electronic components and housings are the main applications area for PBT in the automotive sector. Exterior applications are the next most important market with main uses being bumper fascias, mudguards, door handles, mirror housings and wiper arms. Interior applications include parts of the instrument panels such as ashtrays and 

Polybutylene terphthalate (PBT) is a semicrystalline thermoplastic polyester considered as a medium performance engineering polymer. It is produced industrially in a two-step batch or continuous process. The first step involves the transesterification of dimethyl terephthalate (DMT) with 1,4-butanediol (BDO) to produce hydrobutyl terephtlate (bis-HBT) at a temperature of 200 C. The second step consists to the polycondensation of bis-HBT at 250 C to yield PBT. It exhibits both excellent electrical properties and chemical resistance. When reinforced with glass fibers, it has improved stiffness and mechanical strength. Typical uses include connectors, capacitors and cable enclosures. PBT is also used in hot appliances such as iron and kettles. 

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Following the tolerance stack through the end assembly, the bobbin dimension of 22 mm from the outside face to the back face of the magnetic pole is analysed next. This characteristic dimension does not include the tolerance on the impact extruded pole. The pole is to be moulded into the bobbin and the pole face is considered to be part of a mould related dimension. The bobbin is injection moulded using 30% filled polybutylene terephthalate (PBT). The tolerance assigned to the bobbin dimension is 0.035 mm. 

In a molded polymer blend, the surface morphology results from variations in composition between the surface and the bulk. Static SIMS was used to semiquan-titatively provide information on the surface chemistry on a polycarbonate (PC)/polybutylene terephthalate (PBT) blend. Samples of pure PC, pure PBT, and PC/PBT blends of known composition were prepared and analyzed using static SIMS. Fn ment peaks characteristic of the PC and PBT materials were identified. By measuring the SIMS intensities of these characteristic peaks from the PC/PBT blends, a typical working curve between secondary ion intensity and polymer blend composition was determined. A static SIMS analysis of the extruded surface of a blended polymer was performed. The peak intensities could then be compared with the known samples in the working curve to provide information about the relative amounts of PC and PBT on the actual surface. 

Polybutylene terephthalate (PBT) is another thermoplastic polyester produced by the condensation reaction of terephthalic acid and 1,4-butanediol ... 

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). 

The most common are polyethylene terephthalate (PET) and polybutylene terephthalate (PBT). 

Polymers having many flexibilizing groups (CH2, O), such as polyethylene. polyisoprene, and polysiloxanes (silicones), are flexible. Other less-flexible polymers may be flexibilized by the introduction of flexibilizing groups. For example, polybutylene terephthalate (PBT) is more flexible than polyethylene terephthalate (PET), and nylon 11 is less rigid than nylon 6. 

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). 

Polybutylene terephthalate (PBT), polybutylene succinate, polyurethanes, pyrrol idone, tetrahydrofuran, y-butyrolactone... 

While the condensed phase analysis of the residue (by FTIR-ATR) of PA6 is ongoing, we present the results of TG/ATR for polybutylene terephthalate (PBT)-modihed by a phosphinate FR or nanoparticles (sepiolite) or the combination of phosphinate and nanoparticles. 

The most important representatives of this group are polyethylene terephthalate (PET) and polybutylene terephthalate (PBT). The consumption of PET in the world (excluding fibers) was about 4x 106 t in 1997 (audio and video films, technical mouldings, packaging, particularly bottles). Even though the cost of these plastics is presently in the medium price range, one can count on a reduction in their price in the future due to their widespread use. 

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. 

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. 

Aliphatic polyesters like polycaprolactone (PCL) or polybutylene adipate (PBA) are readily biodegradable, but because of their melting points of 60 °C are unsuitable for many applications. On the other hand, aromatic polyesters like polyethylene terephthalate (PET) or polybutylene terephthalate (PBT) have high melting points above 200 °C and very good material properties, but are not biodegradable. 

The polyamide 6 (PA6) used was a cast film of 50 pm thickness made from an unstabilized PA6. The polybutylene terephthalate (PBT) used was a cast film of 25 pm thickness made of an unstabilized PBT. 

Typical polyesters characterized by GPC include polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and polycylohexylenedimethyl-ene terephthalate (PCT). Polyphthalamides (PPA) and polyamides are also commonly analyzed. 

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). 

Apart from ZHS and ZS, little work has generally been undertaken on tin-based Are retardants in nonhalogen polymer systems. However, certain tin(II) compounds have shown excellent flame-retardant and smoke-suppressant properties when incorporated at levels of 20-30% into aromatic polyesters, specifically polybutylene terephthalate (PBT). Hence, tin(ll) oxide, tin(II) oxalate, and tin(II) phosphate have been shown to markedly increase flame retardancy in PBT, whereas, interestingly, tin(IV) oxide is almost totally ineffective in the same polymeric substrate. 

Reinforced PET- Thermoplastic polyesters based on polyethylene terephthalate. Closely related in terms of chemistry, properties, and areas of application to reinforced polybutylene terephthalate (PBT) compounds. Key distinguishing features are higher strength properties and higher use temperatures. 

Polybutylene terephthalate PBT Rigid, heat resistant, good electrical insulating behavior, dimensional accuracy... 

A well established material for electronic housings is polybutylene terephthalate (PBT) strengthened with glass fibers. It is a cost-effective plastic compound with... 

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