Thermoplastic polymers engineering, characteristics

The selected scenario comprises the conceptual design of a polymerization process for the production of Polyamide-6 (PA6) from caprolactam [99, 104]. PA6 is a thermoplastic polymer with a world production capacity of more than 4 million tons per year (as of 2006). The most frequent use of PA6 is the production of fibers, which are used in home textiles, bath clothing and for carpet production. In addition, PA6 is used as an engineering construction material if high abrasion resistance, firmness, and solvent stability are required. Glass-fiber reinforced and mineral material-filled PA6 is a preferred construction material if a combination of rigidity, elasticity and refractory quality characteristics are required. 

In 1998, PTT was finally introduced to the market by Shell Chemicals under the trade name Corterra, since an economical process for the production of PDO had been developed. PTT fibers are commercially produced today by DuPont and Shell. PTT has special characteristics as a fiber. It is particularly interesting in carpet fibers, where it has shown outstanding resiliency and chemical resistance. Also, this polymer shows potential in the field of engineering thermoplastic polymers and fabrics. 

Reinhart, J. W. Long-Time Hydrostatic Strength Characteristics of Thermoplastic Pipe. Polymer Engineering Science, Oct. 1966. 

Noryl. Noryl engineering thermoplastics are polymer blends formed by melt-blending DMPPO and HIPS or other polymers such as nylon with proprietary stabilizers, flame retardants, impact modifiers, and other additives (69). Because the mbber characteristics that are required for optimum performance in DMPPO—polystyrene blends are not the same as for polystyrene alone, most of the HIPS that is used in DMPPO blends is designed specifically for this use (70). Noryl is produced as sheet and for vacuum forming, but by far the greatest use is in pellets for injection mol ding. 

The presence of the either linkages is sufficient to allow the material to be melt processed, whilst the polymer retains many of the desirable characteristics of polyimides. As a consequence the material has gained rapid acceptance as a high-temperature engineering thermoplastics material competitive with the poly-sulphones, poly(phenylene sulphides) and polyketones. They exhibit the following key characteristics ... 

Engineering resins are polymers designed to excel in. certain physical characteristics. For the most part they are thermoplastics, but they can be thermosets as well. Examples are Nylon 6, Nylon 66, polycarbonates, and polyesters. Phenolics can be considered engineering resins. 

SPS is entirely different from conventional amorphous styrenics in chemical and physical properties. In addition to characteristics such as low specific gravity, excellent electrical properties, hydrolytic resistance and good mold-ability similar to those of existing styrenics, SPS has heat resistance, chemical resistance and the characteristics inherent to crystalline polymers that make it a new engineering plastic. SPS is finding new applications and is expected to bring out new horizons in the application areas of engineering thermoplastics. 

Hahgenated polymers, both brominated and chlorinated, have been developed to yield better polymer compatibility, improve physical properties, and long-term-aging characteristics in many thermoplastic resins, particularly the high-performance engineering thermoplastics, such as nylon, polybutylene terephthalate (PBT) and polyethylene terephthalate (PET). These materials still use antimony oxide as a synergist to achieve the desired flame resistance (31). 

The most stable polyacetal polymer is polyformaldehyde (or polyoxymeth-ylene, POM) this is the only polyacetal that has reached commercial production. This resin has unique properties (e.g., selflubrication) and is very widely used in automotive applications such as engineering plastics. Acetals are widely used engineering thermoplastics with high load-bearing characteristics and low coefficients of friction. Currently, over 200 million lb of acetals are molded and extruded in the United States. 

PPS is an engineering plastic. The thermoplastic grades of PPS are outstanding in heat resistance, flame resistance, chemical resistance, and electrical insulation characteristics. The linear polymers are highly crystalline with melting point in the range of 285-295°C and Tg of 193-204°C. 

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