Polyether sulfone plastic

Specialized high-temperature plastics such as polyether sulfone and polyetherimide are used for components for medical analysis and diagnosis equipment. 

The term HT-thermoplastics is used for polymers, which in the absence of fillers, have a continuous-use temperature above approx. 200 °C. In contrast, standard plastics, such as PVC, polyethylene or polystyrene, have continuous-use temperatures of the order of 100 °C. In addition to their high temperature stability, HT-thermoplastics, in general, possess good resistance to chemicals and usually also low flammability. Among the most important HT-thermoplastics are polyphenylene sulfides (PPS), polysul-fones (PSU), polyether sulfones (PES), polyether imides (PEI), polyetherether ketones (PEEK) and polyarylates (PAR). 

Watterson, E.C., Polyether Sulfones, in Engineering Plastics, vol. 2, Engineered Materials Handbook, ASM International, Metals Park, OH, 1988, p. 161. 

A helical blade used in fluid compressors made of plastics, such as PTFE, PFA (perfluoroalkoxy resin), PEEK (polyetheretherketone), PES (polyether sulfone). 

The postyield ductile fracture of polymers was extensively investigated (170-183), resulting in a conclusion that the crack is initiated from cavities growing from defects in the drawn material. These cavities have a rhombic shape with the long and short diagonals perpendicular and parallel to the draw direction. These cavities were observed in PVC, PE, polyethylene terephthalate (PET) at room temperature and in PC, PMMA, polyether sulfone (PES), and PS at elevated temperatures. At slow strain rates, the growth of these cavities in a plastically deformed material loaded in tension is stable until the critical size is reached resulting in an unstable catastrophic failure. 

Polypropylene is generally used as oriented polypropylene. Polyvinyl chloride film is commonly used in plasticized form. Polyvinylidene chloride is often known as Saran and is generally used in copolymer form with acrylonitrile. Polyethylene terephthalate is a thermoplastic polyester. Polystyrene is sometimes used in biaxially oriented form. Polycarbonates, polysulfones, polyether sulfones, poly-imides, polyetherimides, and several fluoropolymers are also used for specialty applications. 

In a subsequent approach bulky but not interacting with the H3PO4 substituents were chosen for the preparation of polymer electrolytes keeping the well-established pyridine-based aromatic polyether sulfone backbone [20]. In particular, phenyl and tolyl side moieties were introduced. Copolymer X and XI, respectively, since their size is expected to increase the free volume among neighboring polymeric chains in the bulk leading to an enhancement of the copolymers doping ability without the plasticization phenomena of the previously pyridine-substituted copolymers. 

Fig. 19.1 The plastics pyramid according to thermal literature data of common polymers preferred materials for HT-PEM applications are in the upper right region TPI thermoplastic polyimide, PES polyether sulfone, P P)SU poly(phenylene)sulfone, PE E)K polyether(ether) ketone, LCP liquid crystal polymer, e.g., Vectra, PPS polyphenylene sulfide, PTEE polytetrafluoroethylene.

Poly(aryl sulfone) n Also called Polyether-Sulfone. An aromatic polymer consisting of benzene rings linked by both sulfone (—SO2—) groups and ether oxygen atoms. Poly (aryl sulfones) can be synthesized by solution polymerization in a polar solvent. Several commercial products of this type have been developed as reasonably high temperature resistant engineering plastics. 

Fig. 13.1 Polymers used for medical devices for dialysis and peritoneal dialysis. Polyurethane (PUR) is applied as potting material for capillary membranes, silicone tings guarantee a leak-age-free system, polycarbonate and polypropylene are used for casings, and a series of polymers are incorporated as membrane materials (P5M-polysulfone, P S-polyether-sulfone, PA-polyamide, PAAf-polyacrylonitrile, PMMA-polymethylmethacrylate, CIA-cellulose-tri-acetate). PUC-polyvinylchloride as a biomaterial for tubing needs plasticizers for its flexibility, such as D 7/P/DOP-di-ethyl-hexylphthalate/di-octyl-phthalate, TOTM-tn-octyl trimeUitate, DWCif-di-isononyl-cyclohexane...

Polysulfone Plastics. These plastics which were commercialized by Union Carbide are actually aromatic polyethers containing periodic sulfone groups which provide additional resonance stabilization. They have good mechanical properties, creep resistance, and dimensional stability but their outstanding quality is their high heat distortion temperature (345°F.) and resistance to thermal oxidative degradation. Limitations are difficult thermoplastic processability, amber color, and sensitivity to organic solvents. 

Fortunately, the deficiencies of both the classic thermosets and general purpose thermoplastics have been overcome by the commercialization of a series of engineering plastics including polyacetals, polyamides, polycarbonate, polyphenylene oxide, polyaryl esters, polyaryl sulfones, polyphenylene sulfide, polyether ether ketones and polylmides. Many improvements in performance and processing of these new polymers may be anticipated through copolymerization, blending and the use of reinforcements. 

Aromatic polyesters having an amorphous molecular structure. Compared with other amorphous engineering plastics in terms of heat resistance, polyarylates are generally positioned between polycarbonate on the low side and sulfone and polyether polymers on the high side. Compared with crystalline and semi-crystalline engineering plastics, polyarylate resins offer better resistance to warping, and generally comparable mechanical properties. 

---