Reinforced plastics characterization

The frictional properties of TPs, specifically the reinforced and filled types, vary in a way that is unique from metals. In contrast to metals, even the highly reinforced plastics have low modulus values and thus do not behave according to the classic laws of friction. Metal-to-thermoplastic friction is characterized by adhesion and deformation resulting in frictional forces that are not proportional to load, because friction decreases as load increases, but are proportional to speed. The wear rate is generally defined as the volumetric loss of material over a given unit of time. Several mechanisms operate simultaneously to remove material from the wear interface. However, the primary mechanism is adhesive wear, which is characterized by having fine particles of plastic removed from the surface. 

For typical filament winding applications, the fiber reinforcement provides the stiffness and strength required to maintain structural integrity. Thus, material characterization for filament wound structures focuses on characterizing the fiber dominated stiffness and strength properties of the composite. The stiffness of fiber reinforced plastics (FRPs), in the fiber direction, is dominated by the fiber stiffness characteristics. The strength will be influenced by a number of factors, however, and not all of them are related to the fiber, including ... 

Limited at first to the inspection of metallic components, it was later demonstrated that high-frequency magnetic fields causing eddy current production could be applied to the testing of composites containing conductive fibers, or a certain amount of graphite [108.109], Eddy current testing has been successfully applied in the detection and characterization of defects in carbon fiber reinforced plastics (CFRP) panels, helicopter rotor blades, truck tires, and more [110-112]. 

Huque. A., and Raju, P. K. (1995), Sensitivity of the aeoustie impaet technique in characterizing defects. damage in laminated composites, J. Reinforced Plastics Compo.sites. March 1995. 14. 3. 280 296. 

Of the URPs, about 90 wt% of all plastics can be classified as commodity plastics (CPs), the others being engineering plastics (EPs). The EPs such as polycarbonate (PC) representing at least 50wt% of all EPs others include nylon, acetal, etc. EPs include most reinforced plastics. The EPs are characterized by improved performance in higher mechanical properties, better heat resistance, and so forth when compared to CPs. 

The purpose of this chapter is to describe an analytical tool which, when coupled with accelerated material characterization, is capable of predicting the long term durability of reinforced plastics for applications in hostile environments. Throughout the chapter, the words resin and polymer are used interchangeably, and the resin can be thermoplastic or thermosetting, but it must be remembered that thermosetting resins are much less prone to creep and other viscoelastic effects than are thermoplastics. 

J. George, M.S. Sreekala, S. Thomas, A review on interfaee modification and characterization of natural fiber reinforced plastic composites. Polym. Eng. Sei. 41(9), 1471-1485 (2001)... 

Fejes-Kozma, Zs. Karger-Kocsis, J. (1994). Fracture Mechanical Characterization of a Glass Fiber Mat-reinforced Polypropylene by Instrumented Impact Bending. Journal of Reinforced Plastics and Composites, Vol.l3, No.9, pp. 822-834 ISSN 0731-6844 Ferry, J. D. (1980). Viscoelastic Properties of Polymers, 3rd Edition, Wiley Press, ISBN 978-0471048947, New York... 

In this article, we introduce a recently developed ultrasonic spectroscopy method and review its application to polymeric studies. First, the principle of this ultrasonic spectroscopy is explained including the instruments and data analysis methods. Then, actual application of this measuring system is described for the characterization of solid polymers and the observation of phase transition phenomenon in liquid crystals and ferroelectric (VDF/TrFE) copolymer. Finally, the extension of this system to two-dimensional measuring and the application to non-destructive testing of CFRP (carbon fiber reinforced plastics) are discussed. 

Polyesters. Main chain of their macromolecules is characterized by repeated — CO—O— groups. Unsaturated polyester resins are thermosets used mainly for manufacturing glass fibre-reinforced plastics products. The most wide-spread type of thermoplastic polyesters are polymers of an aromatic dicarboxylic acid (mainly terephthalic acid) and an aliphatic diol (e. g. ethyleneglycol or butanediol). The most important representatives of this group are poly(ethylene terephthalate) and poly-(butylene terephthalate). Polyarylate aromatic polyester is a high-temperature thermoplastic of an aromatic dicarboxylic acid (terephthalic acid) and an aromatic diol (bisphenol-A). In the chemical sense, polycarbonate is also a polyester. 

Borysiak S et al (2005) Method of preparation of board composites. Poland Patent No 190,405 George J, Sreekala MS, Thomas S (2001) A review on interface modification and characterization of natural fiber reinforced plastic ctnnposites. Polym Eng Sci 41 1471 Bledzki AK, Reihmane S, Gassan J (1998) Thermoplastics reinforced with wood fillers a literature review. Polym Plast Technol Eng 37 451-468... 

P. Gerard, J. Raine and J. Pabiot, Characterization of fiber and molecular orientations and their interaction in composite injection molding. Journal of Reinforced Plastics and Composites, 17, 922-934 (1998). 

Davalos, J. F. and Qiao, P. (2001), Modeling and characterization of fiber-reinforced plastic honeycomb sandwich panels for highway bridge applications , Composite Structures, Vol. 52, Issues 3-4, pp. 441 52. 

Elsevier-Applied Science Publishers have recently begun to publish a Developments in... series. The separate topics covered are adhesives, composite materials, injection moulding, polymer characterization, polymer degradation, polymer fracture, polymer photochemistry, polymer stabilization, polyurethanes, PVC (production and processing), reinforced plastics, rubber and rubber composites, and rubber technology. 

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