PVC fillers
Briefly introduce the performance of PVC fillers.
PVC fillers
Polyvinyl chloride (PVC) is one of the earliest materials used in plastic fillers and is still used in water treatment and acid mist purification. However, its resistance to temperature and organic solvents is a significant weakness.
Basic Characteristics
Characteristics | Description |
Density | 1.38-1.42 g/cm³ (approximately 50% higher than PP) |
Operating Temperature | ≤60℃ for long-term use, ≤70℃ for short-term use |
Cost | Low |
Corrosion Resistance
Resistant to: Hydrochloric acid, dilute sulfuric acid, dilute nitric acid (<30%), strong alkalis, chlorine, hypochlorite, salt solutions
Not resistant to:
Concentrated nitric acid (>50%), concentrated sulfuric acid (>70%)
Aromatic hydrocarbons (benzene, toluene) – swelling
Chlorinated hydrocarbons (dichloromethane) – swelling
Ketones (acetone), esters (ethyl acetate) – swelling
PVC is not resistant to most organic solvents and will absorb and swell, leading to deformation and failure. This is a key difference between PVC and PP.
Comparison with PP
Comparison Items | PVC | PP |
Density | High (1.4) | Low (0.9) |
Temperature Resistance | ≤70℃ | ≤100℃ |
Organic Solvent Resistance | Poor (swelling) | Good |
Cost | Low | Low |
Applicable and Inapplicable Scenarios
Applicable: Hydrochloric acid absorption tower (≤60℃), wet desulfurization (low-temperature section), acid mist purification tower, water treatment degassing
Inapplicable: Organic systems containing aromatics, ketones, and esters; temperatures >70℃; concentrated nitric acid and concentrated sulfuric acid media
Summary
The performance of PVC packing can be summarized as: acid and alkali resistant, chlorine resistant, but not resistant to organic solvents and temperatures. It still has value in aqueous corrosive media, but its applicable range is much smaller than that of PP. In conditions containing organic solvents, PVC is completely unsuitable, and PP should be preferred.