Formulating the right Polyurethane adhesives or sealants
that can resist to extreme environmental conditions
such as high and low temperatures, humidity and chemical aggressions while ensuring durable high performance
is a challenge.
Polycarbonate Diols (PCD) offer customizable possibilities
with superior and long-term retention of designed performances, without modification of initial properties
after being exposed in harsh environments.
The outstanding durability of Polyurethane adhesives & sealants based on PCD
is obtained thanks to different performances, such as:
Access more information about the best-in-class performances of Polycarbonate Diol-based Polyurethane adhesives, click on the pictures below:
Increased adhesion properties of Polyurethane adhesives
allow adhesive formulators to improve the adhesion properties
of their Polyurethane adhesives.
A cross-cutter adhesion test
was run in order to compare the adhesion properties of Diol-based Polyurethane once a part of the coating was removed (see picture 1)
Picture1: Cross-cut adhesion test
Test method: part of the coating is removed
||0: No modification of adhesion properties
2: from 5% to 10%
Table 1: Modification of adhesion properties of polyol-based Polyurethane after a cross-cut adhesion test
The results in Table 1
show that compared to Polyurethanes formulated with standard diols, those formulated with Eternacoll® PCD
show excellent adhesion properties
after the cross-cut adhesion test.
Moreover, Figures 2 and 3
illustrate that Eternacoll® PCD provide a better T-peel and Lap-shear strength than standard diols for adhesives. This results in an improved durability of Polyurethane adhesives.
|Figure 2: T-peel test of PCD-based Polyurethane adhesives
(kN/m, ISO 11339:2010)
|Figure 3: Lap-shear strength of PCD-based Polyurethane adhesives
(kPa, ISO 4587:2003)
Excellent water resistance of Polyurethane adhesives
Polycarbonate Diols (PCD) allow formulators to provide extremely durable Polyurethane adhesives & sealants
thanks to increased resistance to water / hydrolysis.
illustrates that Eternacoll® PCD-based Polyurethane better retains the initial Polyurethane properties
in extreme humid conditions: Compared to standard Polyether Diols, it shows a very low variation of the T-peel initial value
after exposure to water.
|Figure 4: Water resistance of PCD-based Polyurethane adhesives
Water immersion at 80° C for 15 days
ISO 9142:2003 - Adhesives - Guide to the selection of standard
laboratory ageing conditions for testing bonded joints
Therefore, Polyurethane adhesives
& sealants formulated with Eternacoll®
withstand extreme humid conditions
and remain intact after long-term exposure to water and humidity.
Increased chemical resistance of Polyurethane adhesives
Exposure to harsh solvents and fluids tends to damage Polyurethane adhesives
& sealants over time.
(PCD) can help you to overcome this annoying constraint by enhancing the chemical resistance
of your Polyurethane formulations.
An ethanol resistance test was run in order to compare the chemical resistance of Diol-based Polyurethanes (see picture 2)
As illustrated on Figure 5
, Polyurethane formulated with Eternacoll® PCD shows an improved resistance to harsh solvents compared to Polyurethane based on benchmark Diols.
Picture 2: Ethanol resistance test of
Determination of resistance to liquids
Part 1: Immersion in liquids other than water
Figure 5: Ethanol resistance of Diol-based PU
*5 = Intact adhesive after exposure
4 = Slight change in color
3 = Light mark
2 = Strong mark
1 = Adhesive removal
The use of Eternacoll® PCD in your Polyurethane formulations allows you to provide highly durable Polyurethane adhesives
that can better resist to exposure of chemicals.
This makes Eternacoll® PCD suitable for applications in which Polyurethane adhesives
have to resist to very harsh environmental conditions
High thermal stability of Polyurethane adhesives
Is temperature resistance a must-have
for your Polyurethane adhesives
? If you can’t afford to provide Polyurethane that tends to yellowish over time, then PCD is the technology you have always been looking for!
provide a very high thermal stability to Polyurethane adhesives
compared to traditional Polyester and Polyether Diols, thanks to excellent heat resistance.
illustrates that Eternacoll® PCD based Polyurethane has a very low variation of the T-peel initial value
after artificial weathering, compared to standard Polyether and Polyester Diols.
Eternacoll® PCD based Polyurethane
| Figure 6: Variation of the initial value of T-peel for Diols-based PU
Test conditions: Dry heat, wet heat and cold
ISO 9142:2003 - Adhesives - Guide to the selection of
standard laboratory ageing conditions for testing bonded joints
shows an excellent retention of initial properties
, even after exposition to extreme weather conditions, for an improved durability of your adhesives & sealants!
Therefore, Eternacoll® PCD allow to provide highly durable Polyurethane adhesives & sealants
that resist to heat and can be used for applications exposed to high temperatures.
Improved mechanical properties of Polyurethane Adhesives
Formulating Polyurethane with Polycarbonate Diols (PCD) maximizes the performance of your adhesives & sealants formulation
Polyurethane based on Eternacoll® PCD
shows better mechanical properties
compared to Polyurethane based on traditional Diols:
- The Polyurethane adhesive has a better tensile strength (+329%) and is therefore less elastic (Figure 7)
- It also shows a better hardness (+173%), as illustrated on Figure 8
|Figure 7: Tensile strength of Diol-based PU
||Figure 8: Hardness of Diol-based PU
The improvement of mechanical properties allows you to provide less elastic Polyurethane and with a better hardness, for a highly durable adhesive!
Improvement of adhesion performance thanks to diol blends
Last but not least, you can cost effectively improve the adhesion properties
of your Polyurethane adhesives using blends
of Eternacoll® PCD / standard diols.
Eternacoll® PCD are fully miscible with most of standard diols.
As illustrated on Figures 9 and 10,
you can easily adjust your formulation according to the cost / adhesion performance
you want to get with standard diols content about 10-50% wt. The adhesion improvement can be strongly enhanced compared to standard diol.
|Figure 9: T-peel of PU adhesives using polycarbonate diols blends
Test method: ISO 11339 :2010
25% wt = 25% of Eternacoll® PCD, 75% of benchmark diol (PTMG)
50% wt= 50% of Eternacoll® PCD, 50% of benchmark diol (PTMG)
100% wt= Benchmark PTMG without Eternacoll® PCD
|Figure 10: Lap-shear strength of PU adhesives using polycarbonate diols blends
Test method: ISO 4587:2003