Polypropylene (PPL) a polymer prepared catalytically from propylene which differs from HDPE by having an isostatic replacement of a hydrogen atom by a methyl group on alternate carbon atoms in the main chain. Although largely unreactive chemically the presence of the methyl groups makes Polypropylene slightly more susceptible to attack by strong oxidizing agents than HDPE. A major advantage is Polypropylene's higher temperature resistance.
Excellent resistance (no attack) to dilute and concentrated Acids, Alcohols, Bases and Mineral Oils
Good resistance (minor attack) to Aldehydes, Esters, Aliphatic Hydrocarbons, Ketones and Vegetable Oils
Limited resistance (moderate attack and suitable for short term use only) to Aromatic and Halogenated Hydrocarbons and Oxidizing Agents.
Quick Facts:
Maximum Temperature: 275°F 135°C
Minimum Temperature: 32°F 0°C
Autoclavable: Yes
Melting Point: 338°F 170°C
Tensile Strength: 4,500 psi
Hardness: R95
UV Resistance: Poor
Translucent
Rigid
Specific Gravity: 0.90 |
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KYNAR® (PVDF) is a high molecular weight thermoplastic polymer with excellent chemical inertness. It is highly resistant to oxidizing agents and halogens and is almost completely resistant to allphatic, aromatics, alcohols, acids and chlorinated solvents. It is resistant to most acids and bases. Mechanically strong. High dielectric strength. Thermally stable. Resistant to low temperatures. Stable to ultraviolet and extreme weather conditions. Self-extinguishing and non-toxic.
Quick Facts:
Melting point : 352° F
Heat deflection at 66 psi (ASTM D 648) : 300° F
Heat deflection at 264 psi (ASTM D 648) : 235° F
Maximum serving temperature for short term : 340° F
Maximum serving temperature for long term : 285° F
Thermal conductivity (ASTM C 177) : 1.32 Btu-inch/hr-ft~2- ° F
Specific heat : 0.23 Btu/lb- ° F
Coefficient of linear thermal expansion (ASTM D 696) : 7.1x10~5
Applicable temperature range for thermal expansion : 50-300° F
Mechanical Properties:
Specific gravity (ASTM D 792) : 1.78
Tensile strength, Ultimate (ASTM D 638) : 7,800 p.s.i.
Elongation at break (ASTM D 638) : 80%
Tensile modulus (ASTM D 638) : 3.5x10~5 p.s.i.
Rockwell hardness (ASTM D 785) : R100
Impact strength (73° F) (ASTM D 256) (notched) : 3.0 ft-lb/inch
Flexural strength (ASTM D 790) : 10,750 p.s.i.
Flexural modulus (ASTM D 790) : 3.3x 10~5 p.s.i.
Wear factor against steel 40 psi 50fpm : 1000x10~10
Coefficient of friction 40psi 50fpm : 0.24 Dynamic |