Polythiols are solvent free, typically low viscosity, multifunctional esters made from polyols and mercaptocarboxylic acids. The terminal SH-groups react with epoxy- and isocyanategroups as well as with unsaturated olefins (thiol-ene reaction). The productgroup of the THIOCURE® Polythiols consists of:
(THIOCURE® PETMP, TMPMP, DiPETMP, TEMPIC, GDMP),
(THIOCURE® PETMA, GDMA) and
(THIOCURE® ETTMP, PCL4MP 1350).
Depending on the functionality and the molecular weight of the Polythiol the properties of the resulting polymer can be adjusted. Higher functionality leads to harder polymers, Polymer-Polythiols lead to flexible systems.
We also manufacture custom made products like Polyester-Polythiols which are used in UV-cured coatings.
Polysulfides can be modified with Polythiols leading to Polysulfide Sealants with improved kerosine resistance which are used for sealing aircraft fuel tanks.
Polythiols with higher functionality like the tetrafunctional THIOCURE® PETMP or the trifunctional THIOCURE® TMPMP serve as curing aid for epoxy resins, either in solvent containing formulations, but especially in solvent free coatings, sealing compounds, floor coatings and repair epoxies for the construction sector. They also are used for adhesives and sealants.
With alkaline catalysis already at room temperature a high reaction speed is obtained. In contrary to the standard amine cured epoxies Epoxy/Thiol-Systems harden even at temperatures below zero degree Celsius.
Polythiols are also used in adhesives/glues for mounting SMDs and microchips on electronic circuit boards.
Polythiols in combination with isocyanates are used for coatings and sealing compounds etc. For such Thiourethane-Systems THIOCURE® Polythiols can be used as the sole binder or in combination with standard polyols.
As of today applications like UV cured coatings or concrete floor coatings have been introduced into the market.
In combination with unsaturated chemicals Polythiols react via radical addition reaction. The reaction of such thiol-ene system can be initiated thermally (peroxide or azo-initiators), or as usually done with radiation sensitive initiators (UV-initiators etc.). The latter so called „Click-reaction“ shows a high reaction rate of the double bond of the unsaturated monomer. Thiol-ene systems show low shrinking and no oxygen inhibition. With our THIOCURE® TEMPIC aditionally the adehesion properties on different substrates can be enhanced.
UV-curing systems containing for example the trifunctional THIOCURE® TMPMP may be used in printing inks.
For more Information:
Dr. Tom Beyersdorff
Technical Marketing Manager
Fon: +49 4176 9098-68