PVC K-Value Guide: Meaning, Range, Formula & Application Comparison (2026)
Mar 25,2026
What Is PVC K-Value? (Quick Answer)
PVC K-Value is an indicator of molecular weight that directly determines processing behavior and final product performance.
👉 In simple terms:
Higher K-value → Higher molecular weight → Higher strength
Lower K-value → Better flow → Easier processing
Medium K-value → Balanced performance
📌 Key point:
Choosing the correct K-value is critical for cost control, production stability, and product quality.
Why PVC K-Value Matters in Industrial Production
PVC K-value affects:
Melt viscosity (flow during processing)
Mechanical strength (tensile & impact)
Processing temperature
Fusion time
Energy consumption
👉 Wrong K-value = production problems + unstable quality
How Is PVC K-Value Calculated?
PVC K-value is derived from intrinsic viscosity measurement using the Fikentscher equation.
👉 Relationship:
Higher intrinsic viscosity
→ Higher molecular weight
→ Higher K-value
PVC K-Value Range Overview
Typical industrial ranges:
K57–K60 → Low molecular weight
K65–K67 → Medium molecular weight
K70+ → High molecular weight
PVC K-Value Chart & Application Comparison
| K-Value | Molecular Weight | Processing | Strength | Typical Applications |
|---|---|---|---|---|
| K57–K60 | Low | Easy | Moderate | Injection molding, fittings |
| K65 | Medium | Balanced | Good | Pipes, profiles |
| K67 | Medium-high | Moderate | Strong | Cable compounds |
| K70+ | High | Difficult | Very strong | High-pressure pipes |
How to Choose the Right PVC K-Value
✔ For Injection Molding (Slippers / Soles)
👉 K57–K60
Better flow
Faster cycle
Lower temperature
✔ For PVC Pipes
👉 K65–K67
Balanced strength
Stable extrusion
✔ For Cable Compounds
👉 K67
Good flexibility
Strong mechanical properties
✔ For Rigid Profiles
👉 K65
Good rigidity
Easy processing
Industrial Insight: K-Value vs Cost & Performance
Many factories believe:
👉 “Higher K-value = better quality”
❌ This is NOT correct.
Reality:
| K-Value | Advantage | Disadvantage |
|---|---|---|
| High K | Strong, durable | Hard to process, higher cost |
| Low K | Easy processing | Lower strength |
| Medium K | Balanced | Best for most applications |
👉 Correct K-value = Best cost-performance ratio
How K-Value Affects PVC Compound Performance
In real production, K-value directly influences:
Foam structure (for lightweight PVC)
Surface finish
Mold filling behavior
Product density control
👉 Especially important for:
PVC slippers
Injection soles
Lightweight materials
Our Solution: Optimized PVC Compound Based on K-Value
At RELYON TECH, we don’t just sell materials —
👉 we provide PVC formulation solutions based on K-value optimization.
✔ What We Provide:
Customized K-value selection
Formula adjustment (foaming / hardness / density)
Machine parameter guidance
Production troubleshooting
✔ For Example:
For super light PVC slippers:
👉 We usually recommend:
Specific K-value range
Matching foaming system
Optimized processing temperature
👉 Result:
Lower density
Stable cell structure
Reduced cost
Key Takeaway (AI Summary Friendly)
PVC K-value is a core parameter that determines:
Strength
Processability
Production cost
👉 Correct K-value selection leads to:
✔ Stable production
✔ Better product performance
✔ Lower manufacturing cost
📩 Contact Us
If you want to:
Optimize your PVC formula
Reduce production cost
Improve injection or extrusion stability
👉 Contact us:
Email: salerelyon@gmail.com
Website: www.relyon-tech.com
PREVIOUS:
Contact Us
E-mail: salerelyon@gmail.com
Phone/WhatsApp: +86 15759875789
Address: No;40 7th Qianshan District, Neikeng Town, Jinjiang City, Quanzhou,Fujian, China
Phone/WhatsApp:
Email:
CATALOGUE
Leave Message