General Properties
Short Name:
Name:
PUR
Polyurethane
Polyurethane (PUR) is a polymer produced from the polyaddition reaction of diols/polyols with di-isocyanates and poly-iso- cyanates to generate a urethane group -NH-CO-O-. Since cross-linking is a polyaddition, it is possible to employ aluminum crucibles with pierced lids.
Structural Formula
Properties
| Glass Transition Temperature | 10 to 180°C |
|---|---|
| Melting Temperature | - |
| Melting Enthalpy | - |
| Decomposition Temperature | 240 to 350°C |
| Young's Modulus | - |
| Coefficient of Linear Thermal Expansion | 130 to 200 *10-6/K |
| Specific Heat Capacity | 1.70 to 2.10 J/(g*K) |
| Thermal Conductivity | < 0.19 W/(m*K) |
| Density | 1.10 to 1.70 g/cm³ |
| Morphology | Thermoset |
| General properties | Depending on the composition – the stiffness range expands from soft rubbers to technical plastics. Good abrasion resistance |
| Processing | Injection molding, foaming, coating |
| Applications | Automotive industry. Furniture industry. Building industry. Sports and leisure. Shoe industry (soles). Polyurethane paints and coatings. Casting compounds. Matrix for composites |
NETZSCH Measurement
| Instrument | DSC 204 F1 Phoenix® |
| Sample Mass | 18.95 mg |
| Isothermal Phase | 5 min |
| Heating/Colling Rates | 10 K/min |
| Crucible | Al, pierced lid |
| Atmosphere | N2 (40 ml/min) |
Evaluation
In the 1st heating, the glass transition at 107°C (midpoint) was followed by a broad, shallow, exothermal post-curing effect between approx. 120°C and 200°C (peak temperature 167°C). Due to the post-curing, the glass transition in the 2nd heating (after controlled cooling) was approx. 4 K (midpoint temperature 111°C) higher. The position of the glass transition temperature is directly related to the degree of curing. The more extensive the post-curing, the more the glass transition shifts to higher temperatures.