Chemicals & Polymers Blog

PPG Polyether Polyols

Written by Gantrade | March 11, 2024

The PPG (polypropylene glycol) are core building blocks used in the production of polyurethanes for an endless range of applications.  This family of polyether polyols are the most widely used and versatile group of polyols in polyurethanes, accounting for over 70% of the consumption of polyols in the polyurethane market.  

In polyurethanes, PPG polyether polyols exhibit excellent hydrolytic stability, good low temperature flexibility (Tg’s ~ -65°C), a broad range of hardness values, durability, good resistance to weak acids and bases, ease of handling (liquids at ambient temperatures and low viscosities) and the lowest relative costs.   PPG polyether types are offered in grades designed for rigid polyurethane foam, flexible polyurethane foam, elastomers and others (molded foam, microcellular foam, etc.) applications.  The impressive array of PPG polyether functionalities and molecular weights permits tailoring of polyurethane properties to specific requirements in multiple industries.

The many different application platforms for polyether polyols include the following:

  • -Rigid polyols for construction and building systems 
  • -Rigid polyols for insulation foam materials
  • -High resiliency polyols for automotive seating and panels
  • -Flexible polyols for furniture, cushions, and bedding foam products 
  • -Flexible polyols for packaging protective materials
  • -Flexible polyols for high performance footwear
  • -Flexible polyols for CASE markets

Other applications include sponges, heat and acoustic insulators, vibration dampening, automotive bumpers and floor covering.

The chart below segments the polyether polyol market by end-use applications.

Chemistry

PPG polyether polyols are produced by reacting propylene oxide (PO) monomer with an “initiator” (water, glycerin, sorbitol, sucrose, amines, etc.) under catalytic conditions.  The multifunctional initiators allow the production of very high functionality polyols, a unique feature of the polyether polyols. Molecular weight of these polyether polyols varies from about 300 to as high as 6000. 

Potassium hydroxide has been the traditional catalyst used to produce PPG polyols.  DMC catalyst technology based on Double Metal Cyanides has been introduced to allow the production of high molecular weight PPG polyols with a much higher hydroxyl end functionality.   Ethylene oxide is often used to end-cap or “tip” the PPG polyols to afford the more reactive primary hydroxyl end-group functionality.

The basic chemical structure and the synthetic routes to PPG polyether polyols are shown below.  The structure below shows the secondary hydroxyl functionality of PPG polyols, which accounts for their lower reactivity with isocyanates.

Gantrade’s partner in PPG polyols, SK Purcore Ltd., uses an environmentally clean and cost effective technology to produce the raw material propylene oxide, based on hydrogen peroxide.

Polyol Functionality and End-Use Applications

The hydroxyl functionality of the polyether polyols refers to the number of hydroxyl (-OH) moieties per molecule and can range from diols to six (sorbitol initiated) and eight (sucrose initiated) functional end-groups.  Initiators such as amines (ethylenediamine or triethanol amine) afford triols and tetraols respectively that are self-catalyzing and react faster than the standard polyol initiated PPG polyols. Amine base polyols are used in rigid foam applications.

The functionality of the polyols control properties such as hardness and processing characteristics.  Higher functionalities afford greater crosslinking, which yields harder, more rigid polyurethanes with enhanced thermal and chemical resistance.  Polyols with a molecular weight between 500 and 6000 and functionalities of 1.8-30 are used in flexible foams and CASE elastomers.  High functionality PPG polyols afford highly crosslinked rigid polyurethanes and are used in rigid foam applications and high-performance coatings.

The chart below outlines the general application arenas associated with the various polyol functionalities.

Hydroxyl Functionality Flexible Foam Rigid Foam CASE
2 ★★ ★ ★★
3 ★★ ★★ ★
4 ★★ ★★ -
6 ★ ★★ -
8 - ★★ -


In a foam, polyol functionality also affects foam density, foam cell size, gel times, tack-free times, shrinkage, and foam properties such as thermal conductivity (insulation characteristics).

PPG Polyether Polyol Grades - Gantrade

Gantrade’s grade slate of PPG based polyether polyol is provided below.  This extensive product line is produced by SK Pucore in Korea. Competitive advantages offered by Gantrade’s partner, SK Purcore, include the following:

  • -SK Pucore is a leading company in polyurethanes, committed to sustainable technologies
    -Backward integrated to propylene oxide (PO) monomer
    -The PO monomer process is cost-effective and co-monomer free, using hydrogen peroxide (H2O2)
    -SK Pucore’s plants are new, environmentally friendly, and highly reliable
    -The grade slate is very broad
  • -Unique grades with molecular weights up to 5000, with 8000 MW grades available

Our product line includes PPG polyols designed for flexible slab foam, flexible molded foam, rigid foam and CASE (Coatings, Adhesives, Sealants and Elastomers) markets. PPG polyols for CASE applications are lower in moisture values with higher end-hydroxyl functionality.

Flexible Slab

Bio Polyol

Product OH No 
(mgKOH/g)		 Acid No
(mgKOH/g)		 Water
(%)		 PH Color
(APHA)		 Viscosity
(@25°C, cPs)		 Application
B-5613 54 ~ 58 Max 0.10 Max 0.08 6.5 ~ 8.0 Max 150 Max 1,200 Eco-friendly
B-3235 33 ~ 37 Max 0.10 Max 0.08 6.5 ~ 8.0 Max 120 Max 1,600
B-3784 82 ~ 86 Max 0.10 Max 0.08 6.5 ~ 8.0 Max 300 Max 1,150

 

Base Polyol

Product OH No 
(mgKOH/g)		 Acid No
(mgKOH/g)		 Water
(%)		 PH Color
(APHA)		 Viscosity
(@25°C, cPs)		 Application
Y-5613 54 ~ 58 Max 0.10 Max 0.08 5.5 ~ 7.5 Max 50 470 ~ 530 General
Y-5603 33 ~ 37 Max 0.10 Max 0.08 5.5 ~ 7.5 Max 50 470 ~ 530
Y-4813 46 ~ 50 Max 0.10 Max 0.08 5.5 ~ 7.5 Max 50 470 ~ 530 MAX machine
Y-3531 33 ~ 37 Max 0.10 Max 0.08 5.5 ~ 7.5 Max 50 470 ~ 530 High Resilience
Y-3553 33 ~ 37 Max 0.10 Max 0.08 5.5 ~ 7.5 Max 50 470 ~ 530
Y-3322 20 ~ 24 Max 0.10 Max 0.08 5.5 ~ 7.5 Max 50 470 ~ 530
Y-3328 26 ~ 30 Max 0.10 Max 0.08 5.5 ~ 7.5 Max 50 470 ~ 530
Y-1030 290 ~ 320 Max 0.10 Max 0.08 5.5 ~ 7.5 Max 50 470 ~ 530 Viscoelastic
Y-1024 220 ~ 260 Max 0.10 Max 0.08 5.5 ~ 7.5 Max 50 470 ~ 530

 

Polymer Polyol

Product OH No 
(mgKOH/g)		 Acid No
(mgKOH/g)		 Water
(%)		 PH Color
(APHA)		 Viscosity
(@25°C, cPs)		 Application
Y-7930 28 ~ 32 Max 0.10 Max 0.08 5.0 ~ 8.0 White Max 5,000 High Load Bearing
Y-7530 29 ~ 33 Max 0.10 Max 0.06 5.0 ~ 8.0 White Max 5,500
Y-7320 20.5 ~ 24.5 Max 0.10 Max 0.06 6.0 ~ 8.0 Yellowish White 5,100 ~ 6,200

 

Polymeric Polyol

Product OH No 
(mgKOH/g)		 Acid No
(mgKOH/g)		 Water
(%)		 PH Color
(APHA)		 Viscosity
(@25°C, cPs)		 Application
Y-1537 45.5 ~ 50.5 Max 0.10 Max 0.08 5.0 ~ 8.0 White 600 ~ 950 General
Y-4237 39.0 ~ 44.0 Max 0.10 Max 0.08 5.0 ~ 9.0 White 700 ~ 1,300
Y-4428 42.0 ~ 46.0 Max 0.10 Max 0.08 5.0 ~ 9.0 White 550 ~ 1,050
Y-1564 39.0 ~ 44.5 Max 0.10 Max 0.08 5.0 ~ 9.0 White 1,050 ~ 1,450
Y-3546 28.6 ~ 33.4 - Max 0.08 - Yellowish White 1,050 ~ 1,550

 

Viscoelastic (TDI Base)

Product OH No 
(mgKOH/g)		 Acid No
(mgKOH/g)		 Water
(%)		 PH Color
(APHA)		 Viscosity
(@25°C, cPs)		 Application
Y-1030 290 ~ 320 Max 0.10 Max 0.08 5.5 ~ 7.5 Max 50 230 ~ 330 Pillow & 
Mattress
Y-1024 220 ~ 260 Max 0.10 Max 0.08 5.5 ~ 7.5 Max 50 230 ~ 310
Y-1900 - Max 0.85 Max 0.10 4.5 ~ 7.0 Max 100 650 ~ 800
Y-4118 123 ~ 163 - Max 0.10 - White Max 1,000
Y-2710 90 ~ 110 - Max 0.10 - White Max 1,000

 

Viscoelastic (MDI Base)

Product Water
(%)		 Amine Value
(mgKOH/g)		 Density
(kg/m3)		 ILD
(kgf/314cm2)		 Isocyanate Application
ST-906 1.89 ~ 2.03 1.65 ~ 1.77 55 ~ 60 7 ~ 10 (Package Sale) Pillow & Bed
ST-910

1.90 ~ 2.30

 1.30 ~ 1.40 46 ~ 50 3 ~ 4 (Package Sale) Mattress

 

High Resilience

Product OH No 
(mgKOH/g)		 Acid No
(mgKOH/g)		 Water
(%)		 PH Color
(APHA)		 Viscosity
(@25°C, cPs)		 Application
Y-3531 33 ~ 37 Max 0.10 Max 0.08 5.5 ~ 7.5 Max 50 780 ~ 830 High Resilience
Y-3553 33 ~ 37 Max 0.10 Max 0.08 5.5 ~ 7.5 Max 50 780 ~ 830
Y-3322 20 ~ 24 Max 0.10 Max 0.08 5.5 ~ 7.5 Max 50 1,550 ~ 1,750
Y-3328 26 ~ 30 Max 0.10 Max 0.08 5.5 ~ 7.5 Max 50 1,050 ~ 1,350
Y-7320 20.5 ~ 24.5 Max 0.10 Max 0.08 6.0 ~ 8.0 Yellowish White 5,100 ~ 6,200

 

Flame Retardant

Product OH No 
(mgKOH/g)		 Acid No
(mgKOH/g)		 Water
(%)		 PH Color
(APHA)		 Viscosity
(@25°C, cPs)		 Application
Y-1980 70 ~ 90 Max 1.5 Max 0.10 - - Max 2,200 Flame Retardant
Y-1912 105 ~ 140 Max 2.0 Max 0.08 - - Max 5,000
Y-2980 175 ~ 195 Max 2.0 Max 0.10 - - Max 15,000

 

Flame Lamination

Product OH No 
(mgKOH/g)		 Acid No
(mgKOH/g)		 Water
(%)		 PH Color
(APHA)		 Viscosity
(@25°C, cPs)		 Application
Y-1720 85 ~ 103 Max 0.30 Max 0.08 6.0 ~ 8.0 Max 120 Max 1,500 Flame Laminating

 

CASE

Diol

Product OH No 
(mgKOH/g)		 Acid No
(mgKOH/g)		 Water
(%)		 PH Color
(APHA)		 Viscosity
(@25°C, cPs)
DF-400 265 ~ 295 Max 0.04 Max 0.05 5.5 ~ 7.0 Max 50 50 ~ 90
DF-600 177 ~ 197 Max 0.04 Max 0.05 5.5 ~ 7.5 Max 50 80 ~ 120
DF-750 145 ~ 155 Max 0.04 Max 0.05 5.5 ~ 7.5 Max 50 70 ~ 150
DF-1000 108 ~ 116 Max 0.04 Max 0.05 5.5 ~ 7.0 Max 50 120 ~ 180
DF-2000 54 ~ 58 Max 0.04 Max 0.05 5.5 ~ 7.0 Max 50 260 ~ 340
DF-3000 33 ~ 37 Max 0.04 Max 0.05 5.5 ~ 7.0 Max 50 540 ~ 640
DF-2050 54 ~ 58 Max 0.04 Max 0.05 5.5 ~ 7.0 Max 50 330 ~ 430
DF-2400 44 ~ 48 Max 0.04 Max 0.05 5.5 ~ 7.0 Max 50 400 ~ 450
DF-4000 26 ~ 30 Max 0.04 Max 0.05 5.5 ~ 7.0 Max 50 800 ~ 1,000
DF-4020 26 ~ 30 Max 0.04 Max 0.05 6.5 ~ 8.0 Max 50 800 ~ 1,000

 

Triol

Product OH No 
(mgKOH/g)		 Acid No
(mgKOH/g)		 Water
(%)		 PH Color
(APHA)		 Viscosity
(@25°C, cPs)
TF-400 385 ~ 415 Max 0.03 Max 0.1 6.5 ~ 8.5 Max 50 300 ~ 400
TF-700 225 ~ 255 Max 0.03 Max 0.07 6.0 ~ 8.0 Max 50 230 ~ 310
TF-1000 162 ~ 174 Max 0.04 Max 0.05 5.5 ~ 7.5 Max 50 200 ~ 300
TF-3000 54 ~ 58 Max 0.04 Max 0.05 5.5 ~ 8.5 Max 50 450 ~ 850
TF-4000 40 ~ 44 Max 0.04 Max 0.05 5.5 ~ 7..5 Max 50 600 ~ 700
TF-5000 32 ~ 35 Max 0.04 Max 0.05 5.6 ~ 6.7 Max 50 800 ~ 1,000

 

 

Flexible Molded Foam

Base Polyol

Product OH No 
(mgKOH/g)		 Acid No
(mgKOH/g)		 Water
(%)		 PH Color
(APHA)		 Viscosity
(@25°C, cPs)		 Application
Y-3531 33 ~ 37 Max 0.10 Max 0.08 5.5 ~ 7.5 Max 50 780 ~ 830 High
Resilience
Y-3553 33 ~ 37 Max 0.10 Max 0.08 5.5 ~ 7.5 Max 50 780 ~ 830
Y-3322 20 ~ 24 Max 0.10 Max 0.08 5.5 ~ 7.5 Max 50 1,550 ~ 1,750
Y-3328 26 ~ 30 Max 0.10 Max 0.08 5.5 ~ 7.5 Max 50 1,050 ~ 1,350
Y-1328 26 ~ 30 Max 0.10 Max 0.03 5.5 ~ 7.5 Max 50 1,150 ~ 1,450

Polymer Polyol

Product OH No 
(mgKOH/g)		 Acid No
(mgKOH/g)		 Water
(%)		 PH Color
(APHA)		 Viscosity
(@25°C, cPs)		 Application
Y-7320 20.5 ~ 24.5 Max 0.10 Max 0.06 6.0 ~ 8.0 Yellowish White 5,100 ~ 6,200 High Resilience

 

Systems of Automotive Seats & Headrest

Product Water
(%)		 Amine Value
(mgKOH/g)		 PU Foam Physical Properties Isocyanate Application
Density
(kg/m3)		 ILD
(kgf/314cm2)		 De-molding Time (min)
ST-393 2.25 ~ 2.45 2.00 ~ 3.00 65 22 5 (Package
Sale)		 High Comfort
(Premium Cushion)
BIST-355 3.18 ~ 3.30 1.67 ~ 1.87 50 20 5 Bio Seat Cushion (Back)
BIST-309 3.24 ~ 3.36 4.34 ~ 4.64 45 35 5 Bio Seat Cushion (Hard/Side Bolster)
ST-306B 3.52 ~ 3.70 3.80 ~ 4.20 45 ~ 50 18 ~ 20 4 ~ 5 Seat Cushion
ST-366 3.58 ~ 3.74 3.64 ~ 3.94 42 25 4.5 Seat Cushion
ST-362K 3.69 ~ 3.85 3.23 ~ 3.53 40 25 4.5 Seat Back
ST-521 2.65 ~ 2.85 7.00 ~ 10.00 42 18 0.5 PIP Head Rest
ST-500N 3.48 ~ 3.66 11.49 ~ 11.95 50 30 1 Head Rest
ST-707A 2.65 ~ 2.80 - 85 42 2 Sound Damping
ST-708 2.90 ~ 3.02 4.00 ~ 4.24 60 55 ~ 60 2
 


Systems for Furniture

Product Water
(%)		 Amine Value
(mgKOH/g)		 PU Foam Physical Properties Isocyanate Application
Density
(kg/m3)		 ILD
(kgf/314cm2)		 De-molding Time (min)
ST-313B 3.55 ~ 3.58 2.70 ~ 3.00 45 ~ 50 40 ~ 50 4 (Package Sale) Cushion & Mattress
ST-313D 3.50 ~ 3.75 3.75 ~ 4.25 42 ~ 44 16 ~ 20 5 Cushion & Mattress
ST-313E 3.82 ~ 3.90 4.20 ~ 4.40 55 35 ~ 45 5 Medical Bed
ST-313G 2.93 ~ 3.12 4.36 ~ 4.60 60 10 ~ 15 5 Cushion & Mattress

 

Viscoelastic (MDI Base)

Product Water
(%)		 Amine Value
(mgKOH/g)		 PU Foam Physical Properties Isocyanate Application
Density
(kg/m3)		 ILD
(kgf/314cm2)		 De-molding Time (min)
ST-904 2.25 ~ 2.45 2.40 ~ 2.60 73 ~ 78 4 ~ 5 6 (Package Sale) Pillow
ST-907 3.24 ~ 3.40 1.36 ~ 1.44 62 ~ 67 3.5 ~ 4.5 7
ST-911 - - 41 ~ 44 Max 2 5

 

Systems for Semi-Rigid

Product Water
(%)		 Amine Value
(mgKOH/g)		 PU Foam Physical Properties Isocyanate Application
Density
(kg/m3)		 ILD
(kgf/314cm2)		 De-molding Time (min)
ST-410 1.80 ~ 2.00 7.40 ~ 9.00 180 45 ~ 55 4 (Package Sale) Instrument Panel
ST-801 0.27 ~ 0.33 4.38 ~ 4.60 450 70 ~ 80 2 Steering Wheel
ST-802 - - 450 70 ~ 80 2 AWB-Steering Wheel
ST-600 3.49 ~ 3.67 8.25 ~ 8.69 150 35 ~ 40 6 Sun Visor
ST-414 1.57 ~ 1.67 29.30 ~ 31.10 150 55 ~ 60 4 Door Trim

* Above system can be customized by applications

 

Rigid Foam

Sucrose Base

Product OH No 
(mgKOH/g)		 Water
(%)		 PH Color
(APHA)		 Viscosity
(@25°C, cPs)
SR-383 365 ~ 395 Max 0.10 6.5 ~ 9.5 Slightly Yellowish 5,000 ~ 8,000
SR-451 430 ~ 470 Max 0.10 6.5 ~ 9.5 Slightly Yellowish 3,500 ~ 6,500
SR-453 430 ~ 470 Max 0.10 6.5 ~ 8.5 Slightly Yellowish 11,000 ~ 17,000
SR-500 480 ~ 520 Max 0.10 6.5 ~ 8.5 Slightly Yellowish 3,600 ~ 4,800

 

Amine Base

Product OH No 
(mgKOH/g)		 Water
(%)		 PH Color
(APHA)		 Viscosity
(@25°C, cPs)
RA-401 385 ~ 415 Max 0.10 9.0 ~ 12.5 Reddish 12,000 ~ 22,000
RA-402 380 ~ 420 Max 0.10 9.0 ~ 12.5 Reddish 7,000 ~ 11,000
KL-360 345 ~ 375 Max 0.10 9.5 ~ 11.5 Light Brown 250 ~ 350
LA-480 465 ~ 495 Max 0.08 10.5 ~ 12.5 Transparent 3,500 ~ 7,000
LA-750 730 ~ 770 Max 0.10 10.5 ~ 13.0 Transparent 25,000 ~ 55,000

 

Sorbitol Base

Product OH No 
(mgKOH/g)		 Water
(%)		 PH Color
(APHA)		 Viscosity
(@25°C, cPs)
SL-484 460 ~ 500 Max 0.10 6.0 ~ 8.5 Slightly Yellowish 25,000 ~ 41,000
SL-494 460 ~ 500 Max 0.10 6.5 ~ 8.5 Slightly Yellowish 15,000 ~ 22,000
SL-491 470 ~ 510 Max 0.10 6.5 ~ 8.5 Slightly Yellowish 8,000 ~ 10,000

 

Glycerine Base

Product OH No 
(mgKOH/g)		 Water
(%)		 PH Color
(APHA)		 Viscosity
(@25°C, cPs)
TF-400 385 ~ 415 Max 0.10 6.5 ~ 8.5 Transparent 300 ~ 400
TF-700 225 ~ 255 Max 0.07 6.5 ~ 8.5 Transparent

230 ~ 310
TF-1000 162 ~ 174 Max 0.05 5.5 ~ 7.5 Max 50 200 ~ 300

 

Systems

Application Product Properties
Construction RST 100 Series Customized by
Application
Entry Door RST 200 Series
Spray System for LPG Ship RST 400 Series
Refridgerator RST 500 Series
Cryogenic Insulation System for LNG Ship RST 600 Series
Architectural Mold RST 700 Series
Pipe in Pipe RST 800 Series
Leisure (Picnic Cooler) Others

 

 

Summary

The PPG (polypropylene glycol) family of polyether polyols are the most widely used and versatile group of polyols in polyurethane elastomers. In polyurethanes, PPG polyols exhibit excellent hydrolytic stability, good low temperature flexibility (Tg’s ~ -65°C), a broad range of hardness values, durability, good resistance to weak acids and bases, ease of handling (liquids at ambient temperatures and low viscosities) and the lowest relative costs.

Gantrade’s extensive product line of PPG based polyether polyol is produced by SK Pucore.  Competitive advantages include a very broad range of grades and molecular architectures, including molecular weights in the 5000-8000 range. The propylene oxide monomer technology, based on hydrogen peroxide, is environmentally friendly, cost effective and highly reliable.
PPG polyethers are offered in grades designed for rigid polyurethane foam, flexible polyurethane foam, molded foam and cast elastomers applications.  The extensive array of PPG polyether functionalities and molecular weights allow tailoring of polyurethane properties to specific requirements in multiple industries.

To explore how our range of urethane intermediates can address your unique polyurethane elastomer applications, partner with Gantrade Corporation. Our expert teams, armed with a wealth of technical knowledge and experience, can guide you to the best solutions for your applications. Our global supply chain means high-quality chemical products where you need them when you need them. Contact Gantrade today to learn more.
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