PTMEG
PTMEG (Polytetramethylene Ether Glycol): High-Performance Polyol for Industrial Applications
PTMEG is a premium-grade polyether glycol widely used in the production of spandex fibers, thermoplastic polyurethanes (TPU), and other high-performance elastomers. With its exceptional molecular structure and consistent quality, PTMEG delivers superior performance in demanding industrial applications.
Key Product Specifications
- Chemical Name: Polytetramethylene Ether Glycol
- CAS Number: 25190-06-1
- Molecular Formula: HO-(CH2CH2CH2CH2-O)n-H
- Appearance: Colorless to pale yellow viscous liquid
- Odor: Characteristic mild odor
Technical Parameters
| Parameter | Standard Value | Unit |
|---|---|---|
| Molecular Weight | 650 - 3000 | g/mol |
| Hydroxyl Value | 18.5 - 172.5 | mg KOH/g |
| Acid Value | ≤ 0.05 | mg KOH/g |
| Water Content | ≤ 0.03 | wt% |
| Viscosity (40°C) | 140 - 4500 | mPa·s |
PTMEG Grade Variations
| Grade | Molecular Weight | Primary Applications |
|---|---|---|
| PTMEG 650 | 600-700 | Coating resins, adhesives |
| PTMEG 1000 | 950-1050 | Elastomers, sealants |
| PTMEG 2000 | 1950-2050 | Spandex fibers, TPU |
| PTMEG 3000 | 2900-3100 | High-performance elastomers |
PTMEG FAQ Section 1: Basic Information
What is PTMEG used for?
PTMEG is primarily used as a polyol component in the production of polyurethane elastomers, spandex fibers (Lycra®), and various specialty polymers. It provides excellent elasticity, low-temperature flexibility, and hydrolytic stability to the final products.
How is PTMEG different from other polyols?
Unlike polyester polyols, PTMEG offers superior hydrolysis resistance, better low-temperature flexibility, and higher thermal stability. Compared to polyether polyols like PPG, PTMEG provides higher strength and better elastomeric properties in polyurethanes.
Storage and Handling
- Store in sealed containers under nitrogen blanket
- Recommended storage temperature: 20-40°C
- Protect from moisture and direct sunlight
- Use stainless steel or polyethylene containers
- Shelf life: 12 months from production date
Safety Information
| Parameter | Value |
|---|---|
| Flash Point | > 200°C |
| Autoignition Temperature | > 300°C |
| Vapor Pressure | < 0.1 hPa at 20°C |
| Density | 0.96 - 0.98 g/cm³ at 20°C |
PTMEG FAQ Section 2: Technical Questions
What is the typical acid value of PTMEG?
High-quality PTMEG typically has an acid value ≤ 0.05 mg KOH/g. This low acid value ensures optimal performance in polyurethane formulations and minimizes side reactions during processing.
How does molecular weight affect PTMEG properties?
Higher molecular weight PTMEG (2000-3000) produces softer, more elastic polyurethanes suitable for spandex fibers. Lower molecular weights (650-1000) create harder materials with better mechanical properties, ideal for coatings and adhesives.
Applications of PTMEG
- Spandex Fibers: 65-70% of global PTMEG consumption
- Thermoplastic Polyurethanes: Footwear, automotive parts
- Cast Elastomers: Industrial wheels, mining screens
- Adhesives & Sealants: High-performance bonding applications
- Coatings: Abrasion-resistant surface treatments
Quality Control Parameters
| Test | Method | Specification |
|---|---|---|
| Hydroxyl Value | ASTM D4274 | ±2% of nominal |
| Water Content | Karl Fischer | ≤ 0.03% |
| Color (APHA) | ASTM D1209 | ≤ 50 |
| Viscosity | ASTM D445 | ±10% of nominal |
PTMEG FAQ Section 3: Application Questions
Why is PTMEG preferred for spandex production?
PTMEG provides the ideal balance of elasticity, strength and durability required for spandex fibers. Its regular molecular structure enables uniform polymerization, resulting in fibers with consistent stretch recovery and excellent fatigue resistance.
Can PTMEG be blended with other polyols?
Yes, PTMEG is often blended with polyester polyols or polypropylene glycol to modify the properties of the final polyurethane. Typical blends maintain 60-80% PTMEG content to preserve its superior elastomeric characteristics while reducing material costs.
Environmental Considerations
- Biodegradability: 60-80% in 28 days (OECD 301B)
- Not classified as hazardous under GHS
- Low VOC content (<50 ppm)
- Recyclable through chemical depolymerization
Global Market Overview
| Region | Market Share | Primary Applications |
|---|---|---|
| Asia Pacific | 58% | Spandex, TPU |
| North America | 22% | Industrial elastomers |
| Europe | 15% | Automotive, coatings |
| Others | 5% | Specialty applications |
Conclusion
PTMEG remains the polyol of choice for high-performance polyurethane applications requiring exceptional elasticity, durability and chemical resistance. With precise molecular weight control and rigorous quality standards, our PTMEG products deliver consistent results across diverse industrial applications. For technical specifications or custom formulations, please contact our technical support team.