Polytetrafluoroethylene tensile strength

Fluoropolymers are polytetrafluoroethylene (PTFE) and ethylene tetrafluoroethylene (ETFE). They can assist as redundant insulation and are primarily used as a coating to defend conductor wires from corrosion. The advantages of those materials are their inert and biocompatible behavior and high tensile strength. Otherwise, their stiffness, creep. 

Figure 2.36 shows that addition of this plasticizer to tetrafluoroethylene/peifluoro(alkyl vinyl) ether, TFE/PPVE, increases its melt flow index.Figure 2.37 shows that the addition of plasticizer causes almost hnear increase in the tensile strength. "" This is unusual and it is most likely caused by the modification of crystalhne structure and mode of failure. Addition of this plasticizer to polytetrafluoroethylene, FIFE, improves its mechanical performance and processing abilities by sintering. ""... 

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. 

Polytetrafluoroethylene is a white solid with a waxy appearance and feel. It is a tough flexible material of moderate tensile strength with a tendency to creep under compression. Comparative values for some properties of various fluoro-polymers are given in Table 7.1. The electrical insulation properties are outstanding and are nearly as good as those of polyethylene. The coefficient of friction is unusually low and stated to be lower than that of any other solid the non-stick properties are also excellent. 

Grafting of polytetrafluoroethylene (Teflon) on polydimethylsiloxane has been carried out by milling with the aim of improving solvent (benzene) resistance, tensile strength, and tear resistance [7]. As organosilicone rubber does not readily undergo scission by mechanical action, it was necessary to add benzoyl peroxides to the blend before mixing. Apparently the process is related to the scission of polydimethylsiloxane initiated by peroxide. The... 

Fluoropolymers have outstanding chemical resistance, low coefficient of friction, low dielectric constant, high purity, and broad use temperatures. Most of these properties are enhanced with an increase in the fluorine content of the polymers. For example, polytetrafluoroethylene, which contains four fluorine atoms per repeat unit, has superior properties compared to polyvinylidene fluoride, which has two fluorine atoms for each repeat unit. Generally, these plastics are mechanically weaker than engineering polymers. Their relatively low values of tensile strength, deformation under load or creep, and wear rate require the use of fillers and special design strategies. 

Polytetrafluoroethylene is a white solid with a waxy appearance and feel. It is a tough flexible material of moderate tensile strength with a tendency to creep... 

Table 3.25. Tensile and Izod Impact Strength of Polytetrafluoroethylene ...

Various micronized polytetrafluoroethylene powders were compounded with silicone rubber (MQ) and the mechanical properties of the composites were evaluated. At a PTFE level of only 5 wt%, the fractured surface of the composites showed layered structure morphology. This stracture effectively improved the tear strength of the MQ but it also lowered the tensile properties of the composites. The addition of fluorosUicone rubber (FMQ) as a compatibilizer, improved considerably the tensile and tear strength of the composites. Extrusion of the MQ/PTFE/FMQ composites on an electric wire indicated that the spherical PTFE powder was suitable for the extrusion process [55]. 

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