Reinforced thermoplastics characterization

Travis, J. E., Cianelli, D. A. and Gore, C. R., The long and short of fiber-reinforced thermoplastics. Machine Des., 193-198 (Febmary 1987). Suzuki, N. and Ishida, H., A review on the stmcture and characterization techniques of silane/matrix interphases, Macromol. Symp., 108, 19-53 (1996). 

There are no standard test methods specific for discontinuous fiber (or short fiber) reinforced thermoplastics. It is also not clear whether a geometry-independent fracture parameter can be measured for these nonuniformly inhomogeneous materials. However in spite of these reservations there has been considerable work conducted towards characterizing short fiber composites for fracture toughness using the standard and other procedures outlined in the previous sections. The investigators have recognized that fracture mechanics data provide much more reliable information than the customary alternative tests for material selection and also a service performance indicator for components. 

A.K. Barick, and D.K. Tripathy, Preparation, characterization and properties of acid functionahzed multi-walled carbon nanotube reinforced thermoplastic polyurethane nanocomposites. Materials Science and Engineering B Solid-State Materials for Advanced Technology, 176 (18), 1435-1447, 2011. 

Schirp A et al (2006) Production and characterization of natural fiber-reinforced thermoplastic composites using wheat straw modified with the fungus Pleurotus ostreatus. J Appl Polym Sci 102(6) 5191-5201... 

A.C. Karmaker, and G. Hinrichsen, Processing and characterization of jute fiber reinforced thermoplastic polymers. Polym. Plast. Technol. Eng. 30,609-629 (1991). 

VK Stokes. Random glass mat reinforced thermoplastic composites. Part El. Characterization of the tensile modulus. Polymer Composites 11 342-353, 1990. 

Tankhiwale R, Bajpai SK (2012) Preparation, characterization and antibacterial applications of ZnO-nanoparticles coated polyethylene films for food packaging. Colloid Surf B 90 16-20 Teixetra EdM, Pasquini D, Curvelo AAS, Corradini E, Belgacem MN, Dufresne A (2009) Cassava bagasse cellulose nanofibrils reinforced thermoplastic cassava starch. Catbohydr Polym 78 422 31... 

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]. 

So far, the bulk of literature has concentrated on characterizing the mechanical properties of both thermosetting- - - and thermoplastic-based - knitted composite materials. The modeling of the mechanical properties (mainly stiffness and tensile) has also been popular. However, limited literature exists on the forming property characteristics of knitted fabric-reinforced thermoplastics - and their processing properties are still poorly understood. In fact, most of the literature on forming properties deals with unidirectional, - mostly woven and, to a lesser extent, braided reinforcements, rather than knitted reinforcements. 

Reinforced thermoplastic matrix pipes may be subjected to different types of loading conditions as well as different environmental conditions. However, they may suffer damage due to unexpected working conditions (low velocity impact, such as stones, tools, etc). This paper describes a methodology based upon fracture mechanics to evaluate possible pipe damages. It reports a set of tests made to characterize materials and pipes. Fracture Mechanics tests were made in samples subjected to low velocity impact. The study of damage evolution was done by using the ESPI (Electronic Speckle Pattern Interferometry) technique in order to determine the delamination area. 

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. 

Srinivasan. K., Jackson, W.C., Smith, B.T.. Hinkley, J.A. (1992). Characterization of damage in impact thermoset and thermoplastic composites. J. Reinforced Plast. Compo.sites II, 1111-1126. 

Carbon fiber reinforced composites are at the forefront of current developments in polymer composites, and there is additional evidence for the important role being played by IGC in characterizing the interface in such systems. The Gutmann theory is used by Bolvari and Ward, who report add/base interactions for surface-treated carbon fibers and a series of thermoplastic polymer hosts, including polysulfone, polycarbonate, and... 

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. 

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