Reinforced thermoplastic general properties

Examples of major plastic families Thermoplastic thermal properties are compared to aluminum and steel General properties of thermoplastic General properties of thermoset plastic General properties of reinforced thermoplastic General properties of reinforced thermoset plastic Examples of drying different plastics (courtesy of Spirex Corp.)... 

The formation of a fibrillar structure in TLCP blends makes the mechanical properties of this kind of composites similar to those of conventional fiber reinforced thermoplastics [11,26]. However, because the molecular orientation and fibrillation of TLCPs are generally flow-induced, the formation, distribution, and alignment of these droplets and fibers are considerably more processing-dependent. We do not know ... 

The (property/volume cost) ratios show that the self-reinforced polypropylene has a much higher impact resistance ratio than general-purpose GMTs and glass fibre reinforced thermoplastics but a slightly lower modulus ratio. 

By definition, thermoplastics have limitations at elevated temperatures. It is in this particular property that fibrous glass can lead to remarkable improvements. However, a sharp division exists for reinforced thermoplastics. The various reinforced thermoplastics can be put in two groups relative to DTUL. These consist of amorphous and crystalline or semicrystalline polymers. The amorphous polymers such as styrene-acrylonitrile, polystyrene, polycarbonate, poly (vinyl chloride), and acrylo-nitrile-butadiene-styrene are generally limited to modest DTUL improvements, usually on the order of 20°F with 20% glass. However, crystalline polymers such as the nylons, linear polyethylene, polypropyl-... 

This chapter contains data in tabular form. These data are described in the standard ISO 10350-1 1998, which is titled Plastics—Acquisition and presentation of comparable single-point data—Part 1 Moulding materials. Standard ISO 10350 identifies specific test procedures for the acquisition and presentation of comparable data for many basic properties of plastics. The properties included are often in manufacturers data sheets. In fact many manufacturers, particularly those based in Europe, provide an ISO 10350 Technical Data Sheet, along with a generalized technical data sheet that contains a mixture of ISO and ASTM data. All the data on ISO 10350 are defined by ISO standards rather than ASTM standards. Part 1 applies to unreinforced and reinforced thermoplastic and thermosetting materials, the subject of this book. 

In formulating reinforced thermoplastics, glass fibers with lengths less than 1/4 in. are generally used. Commonly, milled fibers are selected. The fibers improve the physical properties of the base resin, in particnlar the heat-deflection temperatnre. Some thermoplastics are reinforced with graphite fibers to give electromagnetic interference protection. Aramid fibers with thermoplastics resnlt in excellent wear and abrasion resistance. 

Description and general properties. Polymer matrix composites (PMCs) consist of a pol)oner matrix or resin reinforced with glass fibers and to a lesser extent carbon, boron and pol)r-aramide fibers. The resin systems used to manufacture advanced composites are of two basic types thermosets and thermoplastics (see Chapter 11). Thermosetting resins predominate today, while thermoplastics have only a minor role in advanced-composite manufacture. Thermoset resins require the addition of a curing agent or hardener and impregnation onto... 

Fig. 3-20 compares the flexural modulus versus temperatures for four 30% GRTP s. Because modulus is a frequently appearing property in mechanical design equations, creep data often are plotted as apparent or creep modulus. These data are shown in Table 3-6 for GRTP s. As can be seen, the apparent creep modulus improves with glass reinforcement. Generally, the creep modulus of the reinforced thermoplastics decreases as stress and temperature are increased. However, the creep modulus data for reinforced nylon, acetal, polyester, polysulfone, and polyvinyl chloride appear to be less dependent on stress under the conditions of this particular test. When creep modulus data at different stresses coincide—a phenomenon known as the Boltzman superposition—there is an obvious reduction in the amount of testing required. However, such a relationship is both temperature and stress dependent and must be confirmed at the conditions of interest for the specific material involved. Other techniques, such as time-temperature superposition and other empirical correlations, also have been devised to simplify the time-dependent response of plastics ... 

This type of coating is generally used for rubber or thermoplastic elastomers where the double bonds can be used to give coupling and reinforcement. In general, PCC is used where fine particle size is the key factor. This primarily influences mechanical properties and surface finish. Good colour and high purity are also beneficial properties in certain applications. 

The theory, processes, and characterization of short fiber reinforced thermoplastics have been reviewed by De and White [31], Friedrich et al. [32], Summerscales [33], in an introductory text by Hull and Clyne [34], and in a handbook by Harper [35]. Natural fibers and composites have been reviewed by Wallenberger and Weston [36]. The introduction of new composite materials, called nanocomposites, has resulted in new materials that are being applied to various industrial applications. These materials have in common the use of very fine, submicrometer sized fillers, generally at a very low concentration, which form novel materials with interesting morphology and properties. Nanocomposites have been discussed in a range of texts including two focused on polymer-clay nanocomposites by Pinnavaia and Beall [37] and Utracki [38]. 

The rheological properties of fiber-reinforced thermoplastic composites depend on fiber orientation. Therefore, it is very important to understand fiow-induced fiber orientation. For this reason, in this section we first present briefly the approach of Dinh and Armstrong (1984), who developed a constitutive equation for concentrated fiber suspensions in a solvent on the basis of a general formulation proposed earlier by Batchelor (1970). We then present expressions predicting the shear viscosity of fiber-reinforced thermoplastic composite, where the suspending medium is assumed to follow... 

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