The merit of secondary thiols

Odors

KarenzMT PE1 had very weak odor compared to other thiols.
Measurement: Examined by FF-2A ( SHIMADZU CORPORATION )
Odor Concentration :The least dilution multiple that odor can not be felt

Odors

The properties as a chain transfer agent

Thiol acts as a chain transfer agent and proceeds with the next polymerization while regenerating radicals.
Therefore, it possible to use deep curing and curing in low illuminance.
In addition, it has polyfunctional thiol groups, they act as a cross-linking point not only as a chain transfer agent.

[ Chain transfer reaction ]

Chain transfer reaction

[ Radical polymerization ]

Radical polymerization

Rapid curing with epoxy group

The mercapto group create the mercaptide ion in the presence of a basic catalyst.This mercaptide ion has extremely high relative nucleophilic substitution reaction rate compared to other functional groups.
Therefore, it can react proceeds even at low temperatures.
The reaction process is as follows.

[ Generation of mercaptide ions by base ]
Generation of mercaptide ions by base

[ Epoxy ring-opening with mercaptide ions ]
Epoxy ring-opening with mercaptide ions

[ Regeneration of base ]
Regeneration of base

Nucleophilic substituentRelative velocity
C4H9S-680000
C6H5S-470000
C2H5O-1000
C6H5O-400
(CH3)3N30
CH3COO-20
NO3-1

Chem. Rev., 56. 571 ( 1956 )

※ The information contained herein is based upon data considered true and accurate. However, Resonac Corporation accepts no responsibility or risk which may result from the handling and use of products or for infringement of any patent.
※1 It be used ''PETMP'' as abbreviation of Pentaerythritol Tetra (3-Mercaptoproponate).