Reinforced thermosets characterization

Reactive surface treatment assumes chemical reaction of the coupling agent with both of the components. The considerable success of silanes in glass reinforced thermosets have led to their application in other fields they are used, or at least experimented with, in all kinds of composites irrespective of the type, chemical composition or other characteristics of the components. Reactive treatment, however, is even more complicated than non-reactive polymerization of the coupling agent, development of chemically bonded and physisorbed layers render the identification of surface chemistry, characterization of the interlayer... 

In contrast to fibre reinforced thermoset systems, thermoplastics are easy to process. By consolidating a stack of prepregs, a laminate is formed which can be regarded as a sheet material like aluminium and steel. Organic sheet is a characterization which is sometimes found in the literature. 

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. 

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. 

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. 

Roohani M, Habibi Y, Belgacem NM et al (2008) Cellulose whiskers reinforced polyvinyl alcohol copol Tners nanocomposites. Eur Polym J 44 2489-2498 Ruiz MM, Cavaille JY, Dufresne A et al (2000) Processing and characterization of new thermoset nanocomposites based on cellulose whiskers. Compos Interface 7 117-131 Ruiz MM, Cavaille JY, Dufresne A et al (2001) New waterborne epoxy coatings based on cellulose nanofillers. Macromol Symp 16 211-222 Saito T, Nishiyama Y, Putaux JL et al (2006) Homogeneous suspensions of individualized microfibrils from TEMPO-catalyzed oxidation of native cellulose. Biomacromolecules 7 1687-1691... 

A thermosetting resin containing approximately 40% of cardanol by weight has been synthesized by adding an epoxy monomer and an acid-based catalyst to a resole compound (Maffezzoli et al., 2004). This last was manufactured through a polycondensation reaction between cardanol and formaldehyde in the presence of a basic catalyst. The formulation characterized by adequate properties and curing temperatures was reinforced with natural fibers (i.e. short ramie, flax, hemp fibers and a jute fabric) to obtain samples which were then tested both in tensile and in flexural configurations. 

Shah DU, Schubel PJ, Clifford MJ. Mechanical characterization of vacuum infused thermoset matrix composites reinforced with aligned hydroxyethylcellulose sized plant bast fibre yams. 4th International Conference on Sustainable Materials Polymers and Composites (ECOCOMP 2011) July 6-7 Birmingham, UK. 2011. 

B. Wetzel, F. Haupert, K. Friedrich, M. Z. Rong (2003) Mechanical and tribological characterization of thermoplastic and thermosetting polymers reinforced with ceramic nanoparticles, /" Int. Workshop Polym. Compos., IVW, Kaiserslautern. 

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. 

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