High impact strength

Polycarbonates. Polycarbonates (qv) are pardy crystalline thermoplastics with some disorder in the crystalline part and considerable order in the amorphous part. This disorder conveys high impact strength which, combined with its good transparency and outdoor exposure resistance, makes polycarbonates usefiil for vandal-resistant glazing and outdoor lighting. It is easily processed by extmsion and injection mol ding. Various uv and dame-retardant agents are often added. 

HIPS = high impact strength polystyrene, a graft copolymer and blend with polybutadiene. 

High impact strength, increased hardness, lower thermal expansion, and high fatigue strength are also important properties required of denture-base materials. To address these deficiencies, alternatives to the traditional PMMA dentures have been sought. These include the use of other base polymers and reinforced designed denture systems. 

Thermoplastic chlorinated polyethylenes are seldom used on their own but primarily in blends with other polymers, particularly PVC. If chlorination is taken to a level at which the polymer is only semi-compatible with the PVC, a blend with high impact strength may be obtained. In these circumstances the material is classified as an impact modifier. 

Copolymers of vinylidene chloride with 5-50% acrylonitrile were investigated by IG Farben during World War II and found to be promising for cast films. Early patents by ICC and Dow indicated that the copolymers were rigid, transparent and with a high impact strength. 

Of these properties the most interesting is the figure given for impact strength. Such high impact strength figures are in part due to the ductility of the resin. 

Copper retains high impact strength and increases its tensile strength under low temperatures, including cryogenic applications. Typical data are given in Table 3.17. 

It was found that a high-impact strength is obtained in PP-EPDM blends by slow curing with sulfur. Thiuram disulfide N-(cyclohexylthio)phthalimide was used as an inhibitor of curing, and its effect on the impact strength of dynamically cured PP-EPDM blends was studied (Table 6). It was also found that the one-step method of blend preparation also has a favorable effect on the impact strength of the resultant blend system. 

It was found that PP-EPDM blends [30] with a slow curing EPDM have a high-impact strength. Effect of tet-ramethyl thiuram disfulfide (TMTD) concentration on the Charpy notched impact strength of PP-EPDM blend is given in Table 8. 

Articles made from polypropylene have good electrical and chemical resistance and low water absorption. Its other useful characteristics are its light weight (lowest thermoplastic polymer density), high abrasion resistance, dimensional stability, high impact strength, and no toxicity. Table 12-3 shows the properties of polypropylene. 

Nylons are used both in engineering applications and in making fibers. A combination of high impact strength and abrasion resistance makes nylon an excellent metal substitute for bearings and gears. As fiber, nylon is used in a variety of applications, from clothing to tire cord to ropes. 

Lexan, a polycarbonate prepared from diphenyl carbonate and bisphenol A, is another commercially valuable polyester. Lexan has an unusually high impact strength, making it valuable for use in telephones, bicycle safety helmets, and laptop computer cases. 

Styrene maleic anhydride SMA is a copolymer made with or without rubber modifiers. They are sometimes alloyed with ABS and offer good heat resistance, high impact strength and gloss but with little appreciable improvement in weatherability or chemical resistance over other styrene based plastics. 

Melamines Good heat resistance, high impact strength Compression molding... 

An electric conductive rubber base containing carbon black is laminated with an electric conductive cover layer of phosphoric acid ester plasticizer and other ionic surfactants to prepare antistatic mats, where the covers have colors other than black. It is also reported that alkyl acid phosphates act as color stabilizer for rubber. Small amounts of phosphate esters are helpful in restoring reclaimed rubber to a workable viscosity [284,290]. Esters of phosphoric acid are used in the production of UV-stable and flame-retarded alkylbenzenesulfonate copolymer compositions containing aliphatic resins and showing a high-impact strength... 

High-impact strength, solvent resistance, and improved thermal stability Improved impact strength, heat resistance, rigidity, and appearance Superior mechanical properties High-impact strength... 

Polycarbonates are condensation polymers made from phosgene and bisphenol A. They have high impact strength and are used in glazing, helmets, and appliance casings. 

Thermoplastic materials of the polyester family, characterised by high impact strength and dimensional stability up to 140 °C. Polychloroprene See Neoprene. 

Comparison of mechanical and processing properties with morphology shows that the formation of a network structure is the desired morphology for high impact strength, low viscosity and low shrinkage as indicated in Figure 6 for the impact behavior.12... 

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