Temperature Resistance of Plastic Fillers
Briefly describe the temperature resistance of plastic fillers.
Temperature Resistance of Plastic Fillers
The temperature resistance of plastic fillers is one of the most critical performance limiting factors. Different materials exhibit significant differences in heat distortion temperature and long-term service temperature; therefore, operating temperature must be the primary parameter to consider when selecting fillers.
Temperature Resistance of Various Materials
Material | Long-term operating temperature | Short-term withstand temperature | Heat distortion temperature (1.82MPa) |
PP | ≤80℃ | 100℃ | 90-100℃ |
PE | ≤60℃ | 80℃ | 70-80℃ |
PVC | ≤60℃ | 70℃ | 70-75℃ |
CPVC | ≤100℃ | 110℃ | 100-110℃ |
PVDF | ≤150℃ | 160-170℃ | 110-120℃ |
PTFE | ≤260℃ | 280℃ | 120-130℃ |
Temperature Resistance Rating Classification
General Purpose Grade (≤80℃): PP is the most versatile and cost-effective material, suitable for most chemical, environmental, and water treatment applications. PE and PVC have even lower temperature resistance (≤60℃), suitable for low-temperature or aqueous media.
Medium Temperature Grade (80-100℃): CPVC can withstand long-term use temperatures up to 100℃, filling the gap between PP and PVDF, suitable for water-containing corrosive media at 80-100℃.
High Temperature Grade (100-150℃): PVDF is the first choice for high-temperature corrosive applications, suitable for strong corrosive media at 100-150℃ such as hydrochloric acid absorption and wet chlorine treatment.
Ultra-High Temperature Grade (>150℃): PTFE is the only plastic filler that can be used long-term at 150-260℃, but it has low mechanical strength and extremely high cost.
Consequences of Exceeding Temperature Limits
Consequences | Explanations |
Softening and Deformation | The packing softens near the heat distortion temperature, resulting in decreased porosity and increased pressure drop |
Creep and Settling | Under prolonged high temperature and pressure, the packing slowly deforms, reducing bed height |
Strength Reduction | Tensile strength decreases significantly at high temperatures, making it prone to breakage |
Melting and Collapse | Complete melting occurs above the melting point, causing damage to the tower |
Selection level
Operating Temperature | Recommended Material | Notes |
<60℃ | PP or PVC | PP for non-oxidizing media, PVC for water treatment |
60-80℃ | PP | Most common choice |
80-100℃ | CPVC | PP is nearing its limit, CPVC is safer |
100-150℃ | PVDF | The only choice for highly corrosive media |
>150℃ | PTFE | PTFE or use ceramic/metal fillers |
Summary
The temperature resistance of plastic packing can be summarized as follows: PP ≤ 80℃ is the most common, CPVC ≤ 100℃ is for medium-temperature transition, PVDF ≤ 150℃ is used for high-temperature corrosion, and PTFE ≤ 260℃ is the extreme choice. Operating temperature is the primary screening criterion when selecting a packing—PP should be excluded if it exceeds 80℃, and CPVC should be excluded if it exceeds 100℃. Allowing for a safety margin and confirming the actual temperature distribution are crucial for ensuring long-term stable operation.