TiO2 for PVC Profiles & Window Frames
Window frames, fence boards, siding — UV-stable rutile to prevent yellowing and chalking over 10+ years outdoor.
PVC profiles — window frames, fencing, siding, exterior trim, decking — represent one of the most demanding TiO2 applications in plastics. The PVC compound must perform outdoors for 10–25 years without yellowing, chalking, embrittlement, or warpage. TiO2 selection is critical because PVC is particularly susceptible to photochemical degradation, and the TiO2 surface treatment must protect both itself and the PVC polymer.
SEMITI 2160 (Kronos 2160 equivalent) is the workhorse grade for outdoor PVC. SEMITI 2190 is positioned for premium 20-year warranty applications. SEMITI 996 is acceptable for short-service (3–5 year) applications and interior PVC.
Recommended SEMITI grades
Outdoor PVC profile grade — durable for 10+ year window frame and siding service.
Our flagship chloride-process rutile — high tinting strength and broad compatibility for coatings, plastics, and inks.
Premium plastics rutile for high-performance compounds — engineering plastics + outdoor PVC.
Performance requirements
| Outdoor weathering (Florida 5 yr) | Δb* < 2, no chalking grade 2 |
| PVC compatibility (Ca/Zn stabilizer) | No discoloration, no stabilizer antagonism |
| Extrusion thermal stability (190°C) | Δb* < 1.5 |
| Impact retention (10-yr Florida) | Charpy notched > 60% of starting value |
Dosage guidance
Dispersion / processing notes
PVC compounding is done in high-intensity mixers (Banbury or modern continuous compounders) at 180–200°C. TiO2 is added with the PVC resin and stabilizer; output is sheeted and pelletized or fed direct to extruder. Compound thermal stability must be verified at each TiO2 batch.
Formulation tips
- →Use SEMITI 2160 or 2190 for outdoor PVC profile — Kronos 2160 equivalent
- →Pair with modern Ca/Zn or Sn stabilizers — Pb stabilizers are out (regulated in EU, China, Japan)
- →Add UV absorber (HALS 0.1–0.3%, UV-326 or UV-329 0.05–0.1%) for premium 20-year warranty
- →Co-extruded capstock with higher TiO2 (5–7 phr) over standard PVC core (3 phr) is the cost-optimized approach for premium siding
Common pitfalls
Failure modes we've seen in customer trials — worth checking before scale-up.
- ×Using sulfate-process rutile or interior-grade chloride in outdoor PVC — yellowing visible within 18 months
- ×Skipping the UV absorber package — even with premium TiO2, 5-year service is the practical limit without HALS
- ×Inadequate TiO2 dispersion — appears as visible streaks and color non-uniformity in extruded profile
Common questions
What's the minimum TiO2 loading for a 15-year warranty window frame?+
Can recycled PVC use SEMITI 2160?+
Need help picking a grade for pvc profiles & window frames?
Send us your reference grade, formulation type, or competitor TDS. We'll respond with the SEMITI match + sample within 48 hours.