Mechanical properties, characteristics tensile strength

Mechanical properties (yield, tensile strength, and elongation) Thickness, straightness, and other tolerances Surface characteristics and/or coating Is the section formed from a precut or a continuous strip... 

Plastic selection ultimately depends upon the performance criteria of the product that usually includes aesthetics and cost effectiveness. Analyzing how a material is expected to perform with respect to requirements such as mechanical space, electrical, and chemical requirements combined with time and temperature can be essential to the selection process. The design engineer translates product requirements into material properties. Characteristics and properties of materials that correlate with known performances are referred to as engineering properties. They include such properties as tensile strength and modulus of elasticity, impact, hardness, chemical resistance, flammability, stress crack resistance, and temperature tolerance. Other important considerations encompass such factors as optical clarity, gloss, UV stability, and weatherability.1 248>482... 

PHA polymers are thermoplastics that are soluble in halogenated solvents such as chloroform and dichloromethane. Depending on their chemical composition (homo- or copolymer, the hydroxy fatty acids contained), they differ in their physical properties, eg, ductility and elasticity. PHA can be processed on conventional processing equipment. The processability as well as some mechanical properties like impact strength and flexibility can improve when a monomer/comonomer with longer aliphatic chain is used in polymerisation. One of the commercially available types of PHA is polyhy-droxybutyrate (PHB). PHB is similar to polypropylene in some characteristics like melting temperature, tensile strength, moismre resistance, and odour barrier properties (Pouton and Akhtar, 1996). 

Rapid strain-induced crystallization has been associated with the outstanding mechanical properties characteristic of crosslinked NR compared to its synthetic analogue, i.e. crosslinked IR. This may be due in part to a reinforcing effect of strain-induced crystals on the properties of NR as a filler or physical crosslinking junctions. In fact, tensile and tear strengths of crosslinked NR are practically higher than those of crosslinked IR, at the high-speed limit of the tear test." Therefore, it is important to control the rate of crystallization, in order to control the mechanical properties of not only NR itself, but also the NR blends. 

Polymer nanocomposites represent a rapidly expanding research area. Nanocomposites refer to a class of reinforced polymer with a low percentage of well dispersed nanopartieles. These materials often demonstrate notable improvement in properties such as mechanic characteristics, tensile strength, heat and chemical resistance. Nanoparticles can be classified based on how many dimensions are on the nanoscale. The first type is plate-like (e.g. nanoclays) that has a thickness in the nanometer range and lateral dimensions in the sub-micron or micron range. Two types of nanoclay, 20A (Southern Clay) and MHABS (a surface modified clay 20A), are used in our research. The second type has two dimensions in the nanometer range, such as carbon nanofibers (CNF) or carbon nanotubes. The third type has three dimensions in the range of nanometer, such as spherical silica particles. The latter type of nanoparticle is not used in our study. 

Most of the polymer s characteristics stem from its molecular stmcture, which like POE, promotes solubiUty in a variety of solvents in addition to water. It exhibits Newtonian rheology and is mechanically stable relative to other thermoplastics. It also forms miscible blends with a variety of other polymers. The water solubiUty and hot meltable characteristics promote adhesion in a number of appHcations. PEOX has been observed to promote adhesion comparable with PVP and PVA on aluminum foil, cellophane, nylon, poly(methyl methacrylate), and poly(ethylene terephthalate), and in composite systems improved tensile strength and Izod impact properties have been noted. 

Aramid Fibers. Aromatic polyamide fibers exhibiting a range of mechanical properties are available from several manufacturers, perhaps the best known being Du Pont s proprietary fiber Kevlar. These fibers possess many unique properties, such as high specific tensile strength and modulus (see Fig. 4). Aramid fibers have good chemical resistance to water, hydrocarbons, and solvents. They also show excellent flame retardant characteristics (see High PERFORMANCE fibers Polyamdes). 

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