Talc is one of the most useful mineral fillers which are compatible with the polypropylene (PP).
Talc filled PP is used to produce water pipes.
Different types of Pipes are
| Cold & Hot Water Pipes | Drinking Water Pipes, |
| Pressurised Water Pipes, | Sewage Water Pipes. |
Talc increases rigidity, creep strength and impact resistance (particularly at low temperatures). This makes PP/talc the environmentally friendly alternative to PVC.
Benefits of using Talc as filler for PP
Stiffness (E-Modulus)
Talc increases stiffness ( E-modulus) in plastics.
The degree of rigidity depends on the filling level, aspect ratio and fineness of the talc.
Thermal Conductivity
Talc’s significantly higher thermal conductivity (compared to the polymer), enables heat which is introduced and generated during processing to be transmitted through the mixture more quickly.
This is particularly useful for domestic hot water pipes which need to retain their stiffness and creep resistance at higher temperatures.
Impact Strength
Talc improves impact strength.
At 5 to 10% loading levels the Impact strength improves considerably, however this is primarily due to an increase in the crystallisation of the PP and not the mechanical properties of the talc itself.
This benefit is lost if the loading exceeds higher loading levels.
Chemical Resistance
Talc is water repellent and chemically inert.
TYPICAL COMPOSITION OF TALC FILLED PP PIPE
(The below figures are for reference only).
| INGREDIENTS | LEVEL OF ADDITION IN % |
| Polypropylene | 10-70 |
| Toughener (LLDPE / POE (ethylene – octene copolymer) | 5-20 |
| Micronized Talc | 5-40 |
| Micronized Calcium Carbonate | 5-40 |
| Impact Modifier | 1-5 |
| Dicumyl Peroxide | 0.1-2.0 |
| Antioxidant 1010 | 0.4-2.0 |
| Silane Coupling Agent | 0.5-3.0 |
| Polypropylene Wax | 0.5-3.0 |
| Calcium Stearate | 0.5-3.0 |
| Pigment | 0.4-4.0 |