Expanding the Possibilities of Polyurethanes with Placcel® Polycaprolactone Polyols.

For over a decade, Gantrade and Daicel ChemTech have worked in close partnership to bring the exceptional performance of Daicel’s Placcel® polycaprolactone polyols to the polyurethane market. With a diverse portfolio of more than 50 unique grades, Placcel® polyols are engineered to address a broad spectrum of formulation challenges—both common and complex—within the polyurethane elastomer industry.

Whether you're optimizing an existing system or developing a new one, our teams are ready to help you unlock next-level performance through advanced material design.

Why Choose Placcel® Polyols?

Placcel® polycaprolactone polyols, derived from a broad array of initiators, are known for delivering outstanding properties to polyurethane elastomers, including:

✅High hydrolytic stability and minimal water absorption

✅Superior thermal performance — heat resistance with low-temperature flexibility

✅Durability — excellent tear, impact, and abrasion resistance and dynamic properties

✅Enhanced flex-fatigue life, elastic memory, and inherent toughness

✅Chemical, oil, and hydrolysis resistance

✅Excellent weatherability and UV stability

✅Long-term performance in harsh, demanding environments

Tailored Products; Targeted Performance

Backed by Daicel’s manufacturing expertise, specific grades of the Placcel® polyols impart enhanced performance in any of the categories above.

The caprolactone polyols are available in molecular weight ranges from 400 to 4000, and are offered as diols, triols and tetraols. They are created by a facile Ring-Opening Polymerization (ROP) process under mild conditions using an “initiator” diol or triol and caprolactone monomer. The choice of initiator directly influences the performance attributes of the resulting polyurethane elastomer. The process is depicted below

There are over 50 grades of Placcel polycaprolactone polyols available.

Influence of Initiator Type

Below are just some of the “initiator” comonomers (R-[-OH]_f) that are used in building polycaprolactone polyols, and the key characteristics in the resulting polyurethane elastomer.

The molecular features of the various initiators express themselves in polyurethanes characteristics such as crystallization tendencies (cold hardening), dynamic properties, strength, and durability. Some initiators like NPG, DEG and TMP afford liquid polyols at lower molecular weights. The triblock diol with PTMEG initiator, and the NPG and DEG initiators afford PUR soft blocks exhibiting a low propensity to crystallize and enhanced clarity in a PUR elastomer.  

To exemplify, the DSC Tm and Freeze Point of 2000MW polycaprolactone polyols initiated with NPG, DEG and BDO are shown below. The influence of the linear structure of DEG, EG, and BDO are manifested in the data.

Low Acid Values in Polycaprolactone Polyols

A key feature of polycaprolactone polyols are their very low acid values since their synthesis does not involve a carboxylic acid intermediates. Residual acid catalyzes ester hydrolysis, hence the low acidity and the inherent hydrophobic nature of these polyols, affords polyurethanes with greater hydrolysis resistance. 

Exemplary are the low acid values of Placcel 220T with an acid value of 0.01 mg.KOH/g vs. values above 0.50 mg. KOH/g for conventional adipate based polyester polyols. The improvements in hydrolysis resistance for the Placcel T series manifests itself in very good tensile strength retention values for Placcel 220NT when compared with Placcel 220N, PTMEG 2000 (a hydrophilic diol) and a 2000 MW HDO adipate, in a wet environment at 80 °C. 

Polycarbonate diol (PCD) reference data is provided since PCDs are known to exhibit the highest retention of wet properties in a polyurethane formulation. See the chart below. 

The low acid values also result in higher reactivities of the hydroxyl end-groups with isocyanates, since acidity often reduces the activity of catalysts that may be incorporated. Daicel has developed low acidity grades that exhibit low reactivity with isocyanates, without compromising the benefits of low acidity.

Narrow MWD Polyols

A significant reduction in polydispersity (MWD) has been achieved with the Placcel N series of diols. See the chat below. This results in superior dynamic properties, excellent elastic recovery and resiliency properties, high transparency and light transmission and other attributes. 

The manifestations of diol molecular weight and narrow polydispersity can be observed in the table below which compares the properties for three different MW grades of polycaprolactone polyols in a TPU at equivalent hardness values. The lower molecular weight polyols show superior transparency, high tear strength, and high elastic recovery. The higher MW polyols exhibit better low temperature performance, higher elongations and reduced compression set values.

Basic Properties of TPUs Based on MW Grades

Initiator Influence on TPU Properties

A comparison of the mechanical properties of polyurethanes derived from EG and DEG (PCL 220UA), as well as the effect of a narrow MWD (PCL 220N), are shown in the table below at different Shore A hardness values. The Shore A values were tailored by adding additional polycaprolactone diol into the 1,4-butanediol chain extender. This is indicated by the line-item ‘PCL Content’; for 90 Shore A, only BDO was used as the chain extender. The pre-polymer process was used, starting with the MDI prepolymer (NCO 10.0%) of the respective 2000 MW Placcel grades. The Isocyanate Index (NCO/OH) was 1.03. After mixing the prepolymer and chain extender at 80ºC, the reactants were cast into a mold at 120ºC and cured at this temperature for 17 hours. 

Comparison of TPUs from Various 2000 MW Placcel Polyols

Property changes with the two initiators and the MWD variations are shown in the above table.

Application Versatility

Placcel® polyols are ideal for a wide range of polyurethane elastomer applications, including:

✅Coatings, Adhesives, Sealants & Elastomers (CASE)

✅Paint protection films and surface protection

✅Polyurethane dispersions for leather and textile coatings

✅Mining, oil & gas equipment components

✅Conveyor belts, hydraulic and pneumatic seals, and gaskets

✅Automotive parts

✅Medical-grade devices

Each class of polyol brings unique advantages to polyurethane systems. Choosing the right polyol can significantly enhance end-use performance and durability.

Let Gantrade Guide Your Polyurethane Innovation 

At Gantrade, we pair deep technical insight with a broad product portfolio to help you identify the optimal polyol for your formulation needs. Our long-standing collaboration with Daicel ChemTech enables us to combine technical expertise and customer-focused support to deliver targeted solutions tailored to your performance goals.   We offer not just products—but collaborative partnerships, expertise, and innovation.

Ready to elevate your polyurethane systems? 

Contact Gantrade today to learn how Placcel® polycaprolactone polyols can give your formulations a competitive edge.