Reinforced polybutylene terephthalate

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. 

Elongation decreases dramatically from 250% for unreinforced polybutylene terephthalate to 2.3% for 45% glass fiber-reinforced polybutylene terephthalate (Table 3.4). Izod impact strength is virtually unaffected by the incorporation of glass fiber into the formulation. 

Gears mannfactnred from fiber-reinforced polybutylene terephthalate have an extremely smooth snrface and high maximum operating temperature up to 170°C. This composite is superior to polyacetal or metals and is often used in the manufacture of engine housings. 

Change in impact strength in glass fiber-reinforced polybutylene terephthalate (different ootors) during weathering in the Weatherometer [83], [501]... 

Figure 5.146 Long-term behavior of irradiated and non-irradiated crosslinkable, glass fiber-reinforced polybutylene terephthalate [739]...

Testing has taken place to compare LCPs with two materials used widely for electronic and telecommunications components glass-filled polyphenylene sulphide (PPS) and glass-reinforced polybutylene terephthalate (PBT). Over the temperature range 50-200 °C, the CTEs for the connectors made from the different plastics were 11 ppm/°C, for... 

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. 

To summarize, many fibre-reinforced thermoplastics are not suitable for extended exterior exposure where the maintenance of appearance is important unless their surface is protected. Some unprotected applications that are found include car door handles, rear-view mirror housings and body panels (for all of which polyamides, polyethylene terephthalate and polybutylene terephthalate are used), as well as parts for caravans, boats and snowmobiles. 

Chapter 7, Polybutylene Terephthalate, from LG Chem, describes the science and technology of PBT blends, compounds, and composites. The chapter offers details on the advantages of different polymer blends, types of fiber, and mineral and fiber-mineral hybrid reinforcements as well as chemical and hydrolysis resistance, flammability, and other PBT attributes. The author states that the most important apphcations of PBT are automotive and electrical, electronics and telecommunications, as well as precision engineering and general mechanical engineering, and concludes that the ability to modify for various applications, combined with a range of reinforcement and blend, has enabled PBT as one of the most widely used engineering polymers. ... 

It is seen in Table 3.1 that polyamide 6 improves its tensile strength from a value of 40 MPa to 145 MPa, that is, by a factor of about 3.6. The improvement obtained by the incorporation of glass fiber into polybutylene terephthalate was even more dramatic, from 52 to 80-196 MPa. Very useful improvements in tensile strength result from the incorporation of glass fiber into the formulation. Such improvements ranged from 17 to 41 MPa on unreinforced polymer to 180 MPa on glass-reinforced polytetrafluoroethylene. 

Reinforced polymers that combine high tensile strength with high flexural modulus include polybutylene terephthalate, polyether ether ketone, polyamide-imide, and polyethylene terephthalate (see Table 3.3). 

Polybutylene terephthalate 10%-30% glass fiber reinforced Automotive distribution caps... 

Polybutylene terephthalate 30% glass bead reinforced Engineering parts... 

Polybutylene terephthalate 45% and mineral glass fiber reinforced —... 

Such improvement cannot, however, be taken for granted. No improvement in fire retardancy characteristics was observed when a wide range of filler/reinforcing agents were incorporated into non-fire retardant polycarbonate, polybutylene terephthalate, polyethylene terephthalate, polyamide 6,6, or styrene acrylonitrile copolymer. 

The two major TPs are polybutylene terephthalates (PBT) and polyethlene terephthalates (PET). These crystalline, high-molecular-weight polymers h ive an excellent balance of properties and processing characteristics. Unreinforced and glass-fiber-reinforced grades... 

Figure 5.199 Property profiles and temperature-time curves of polybutylene terephthalate [764] Left unreinforoed Right glass fIber-reInforced...

The example of glass fiber-reinforced PA 6 shows that the thermal-mechanical behavior of polyamide 6 and polybutylene terephthalate can be improved by electron irradiation so that the material can withstand an industrial soldering process at a temperature of 255 °C (such as used in lead-free soldering) [807], [720]. Figures 5.250 and 5.251 illustrate this by two examples. 

Thermoplastic polyesters include unfilled or reinforced grades of polycarbonates, polyethylene terephthalate, polybutylene terephthalate and blends and copolymers of these plastics. Cyanoacrylates and urethanes bond well to these materials. UV-cured acrylics are suitable for transparent plastics such as polycarbonate. 

Figure 14.4 Capillary rheology of 30% glass fiber-reinforced SPS versus 30% glass fiber-reinforced liquid crystalline polymer (LCP),poly(l,4cyclohexamethylene tere-phthalate) (PCI), and polybutylene terephthalate (PBT). All resins were tested 50°C above their melting point.

Figure 14.9 Spiral flow length of various materials. PBT polybutylene terephthalate GF glassfiber reinforced PPS polyphenylene sulfide IR ignition resistant.

Pocan is Bayer s trade name for its partially crystalline thermoplastic polyesters based on polybutylene terephthalate. Product offerings include PBT filled injection moulding grades, PBT elastomer modified and PBT standard non-reinforced injection moulding grades. PC/PBT blends, elastomer modified and non-reinforced injection moulding grades, are also available. 

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