PP (isotactic): Polypropylene
- Short Name
- PP (isotactic)
- Name
- Polypropylene
- Group
- CTP - Commodity Thermoplastics
- General Properties
- Chemical Formula
- (C3H6)n
- Structural Formula
-
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Properties
- Glass Transition Temperature
- -20 to 20 °C
- Melting Temperature
- 160 to 165 °C
- Melting Enthalpy
- 207 to 209 J/g
- Decomposition Temperature
- 450 to 470 °C
- Young's Modulus
- 1300 to 1800 MPa
- Coefficient of Linear Thermal Expansion
- 130 to 180 *10¯6/K
- Specific Heat Capacity
- 1.8 J/(g*K)
- Thermal Conductivity
- 0.17 to 0.25 W/(m*K)
- Density
- 0.90 to 0.91 g/cm³
- Morphology
- semi-crystalline
- Identification
- white granule
- General properties
- Easy to process, Good combination of stiffness and toughness, Good chemical resistance, High stress corrosion resistance, High electrical resistance, Better stability, hardness and stiffness than PE
- Processing
- Injection molding, extrusion, deep drawing
- Applications
- Food containers, packaging, Automotive engineering, Sports equipment, textiles, toys, Building industry
- Modifications
- Co-Po with PE, Compounds with rubber, minerals, reinforcement, colored
- Manufacturer
- Lyondellbaseel, Borealis, DOW, Exxon, Sabic
Internet Links
| Wikipedia: http://en.wikipedia.org/wiki/Polypropylene |
NETZSCH Measurements
- Instrument
- DSC 204 F1 Phoenix®
- Sample Mass
- 5.67 mg
- Isothermal Phase
- 10 min/3 min/10 min
- Heating/Colling Rates
- 10 K/min
- Crucible
- Al, pierced
- Atmosphere
- N2 (40 ml/min)
Evaluation
For commercial semi-crystalline PP types, a melting temperature (represented by the peak temperature) of approx. 160°C to 165°C is typical. This correlates well with the present case, in which peak temperatures of 168°C and164°C were observed in the 1st heating (blue) and the 2nd heating (green), respectively, with corresponding melting enthalpies of 94 J/g (1st heating) and 112 J/g (2nd heating). The lower melting temperature in the 2nd heating can be attributed to better contact between the sample and crucible bottom after the first melting (in the 1st heating). The difference in the heat of fusion results from the different cooling conditions used during production or processing of the polymer and during the measurement (cooling rate: 10 K/min).
The glass transition step for PP can usually be found between -20°C and +20°C. In the present example, it was at -8°C (2nd heating). In the 1st heating, the glass transition was barely detected.
The glass transition step for PP can usually be found between -20°C and +20°C. In the present example, it was at -8°C (2nd heating). In the 1st heating, the glass transition was barely detected.