Short glass fibers thermoplastic polymers

Fig. 11.24 The effects of the fiber aspect ratio, at constant 30% wt loading, on glass-filled polyamide-6. [Reprinted by permission from H. M. Latin, Orientation Effects and Rheology of Short Glass Fiber-reinforced Thermoplastics, Colloid Polym. Sci., 267, 257 (1984).]...

H. M. Laun, Orientation Effects and Rheology of Short Glass Fiber-reinforced Thermoplastics, Colloid Polym. Sci., 262, 257-269 (1984). 

The reinforcement of thermoplastics, notably polypropylene (PP) and polyamide (PA), with short glass fibers is a classical method to improve polymer mechanical properties. Fibers are dispersed more or less homogeneously in the polymer by melt compounding techniques such as twin screw extrusion to produce compounds ready for injection molding. Molded parts benefit from the better mechanical properties of the reinforcing fibers as the fibers bear a considerable part of the load applied to the composite structure. 

H. Anuar, S.H. Ahmad, R. Rasid, and N.S. Nik Daud, Tensile md impact properties of thermoplastic natural rubber reinforced short glass fiber and empty fruit bunch hybrid composites. Polym. Plast. Technol. Eng. 45, 1059-1063 (2006). 

Rjr some polymer blends with a MFC structure, the mechanical properties are about the same as those of commercial short glass fiber reinforced thermoplastics with the same matrix. 

Crowson, R.J., Folkes, M.J. and Bright, P.F. (1980) Rheology of short glass fiber-reinforced thermoplastics and its applications to injection molding I. Fiber motion and viscosity measurement, Polym. Engg Sci., 20,925-33. 

Fiber orientation was studied for different thermoplastic polymers reinforced by short glass fibers, using a special specimen preparation treatment for reflected light microscopy... 

SPS is a semicrystalhne polymer with a glass transition temperature (Tg) of 100°C and a crystaUine melting point (Tm) of 21Q°C. SPS readily accepts fillers, and by compounding with short glass fibers, the heat deflection temperature can be increased to close to the crystalline melting point. A comparison of the Tg and Tm of SPS with other engineering thermoplastic materials is shown in Figure 15.1. 

Crowson, R. J. and Folkes, M. J., Rheology of short glass fiber-reinforced thermoplastics and its application to injection molding II. The effect of material parameters, Polym. Eng. ScL, 20, 934-940 (1980). 

Laun HM (1984) Orientation effects and rheology of short glass fiber-reinforced thermoplastics. Colloid Polym Sci 262 257-269... 

As one might expect, any fiber-polymer system is unique, not only because of the differences in the respective properties of the components, but also because the fiber surface properties and the polymer chemistry have important effects. Not all aspects are yet understood and any generalization would indeed be abusive. A clear demonstration of this fact is offered when comparing the effect of a given type of short glass fiber (E-glass), at constant loading (30%) in different thermoplastics (Table 7.2). 

Lightweight reinforced thermoplastics materials with great strength and stiffness are needed in a number of so-called technical applications. Therefore short glass fibers are used to stiffen thermoplastics, for instance polypropylene, polyamides and also more technical polymers such as polybutylene terephthalate. Thermoplastic processors do not compound themselves their materials and consequently there is quite a large choice of ready-to-be-processed SGF reinforced thermoplastic composites. Table 7.6 gives the average properties of typical commercial PP-SGF composites, as compiled from manufacturers data sheets (when available). 

Strands of glass, (usually E glass) are mechanically cut into lengths from 0.25 to 2 in. and are used to reinforce molding compounds. The longer lengths are used with thermoset resins whereas the short fibers are used with thermoplastic polymers. 

An example of a typical material composition is the combination of a polymer and a filler. Because compounding is a techiuque that can complement the drawbacks of conventional polymers, it has been studied over a long period and its practical apphcations are well known. Reinforcing materials such as short-fiber are often used for compounding with thermoplastic polymers in order to improve their mechaiucal or thermal properties. Polypropylene and polyamide (nylon) are used for the thermoplastic polymers, while glass fiber and carbon fiber are mainly used as reinforcing materials. A few ttm... 

A. Vaxman, M. Narkis, A. Siegmann and S. Kenig, Short fiber reinforced thermoplastics. II. Interrelation between fiber orientation and rheological properties of glass fiber-reinforced Noryl, Polymer Composites, 10, 78-83 (1989). 

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