TY - BOOK

T1 - Low Migration Photoinitiators for Thiol-ene and Water Based Systems

AU - Roth, Meinhart

N1 - no embargo

PY - 2015

Y1 - 2015

N2 - The present work deals with the topic of low migration photoinitiators for biocompatible thiol-ene and UV curable water based resins. The focus was set on the synthesis and characterization of novel photoinitiators, to enable a migration reduction of unreacted photoreactive species and related cleavage products. To realize an improvement in terms of migration stability three different strategies were pursued. Among these were polymerizable photoinitiators, which lead to a decrease of the initiator mobility by copolymerization of the photoreactive species as well as oligomeric and polymeric photoinitiators which reduce the unwanted migration as a consequence of their enhanced molecular weight. The synthesized type 1 and type 2 photoinitiators were evaluated for their usability in thiol-ene and water based resins and characterized referring to their photochemical performance. Attributed to the modification of the novel Initiators with vinyl carbonate and alkyne functionalities excellent results in terms of migrations stability could be obtained for thiol-ene based resins, whereas also a significant improvement for the carbohydrate based initiators in aqueous formulations could be observed. Furthermore macromolecular photoinitiators were investigated, which might be a promising alternative to conventional initiator systems. Additionally new, low viscous silicon based mercapto compounds were synthesized and compared with commercially available thiols to evaluate their suitability for corresponding thiol-ene resins. These novel monomers led to a significant enhancement in term of storage stability of the related resins and the obtained polymers exhibited improved mechanical properties.

AB - The present work deals with the topic of low migration photoinitiators for biocompatible thiol-ene and UV curable water based resins. The focus was set on the synthesis and characterization of novel photoinitiators, to enable a migration reduction of unreacted photoreactive species and related cleavage products. To realize an improvement in terms of migration stability three different strategies were pursued. Among these were polymerizable photoinitiators, which lead to a decrease of the initiator mobility by copolymerization of the photoreactive species as well as oligomeric and polymeric photoinitiators which reduce the unwanted migration as a consequence of their enhanced molecular weight. The synthesized type 1 and type 2 photoinitiators were evaluated for their usability in thiol-ene and water based resins and characterized referring to their photochemical performance. Attributed to the modification of the novel Initiators with vinyl carbonate and alkyne functionalities excellent results in terms of migrations stability could be obtained for thiol-ene based resins, whereas also a significant improvement for the carbohydrate based initiators in aqueous formulations could be observed. Furthermore macromolecular photoinitiators were investigated, which might be a promising alternative to conventional initiator systems. Additionally new, low viscous silicon based mercapto compounds were synthesized and compared with commercially available thiols to evaluate their suitability for corresponding thiol-ene resins. These novel monomers led to a significant enhancement in term of storage stability of the related resins and the obtained polymers exhibited improved mechanical properties.

KW - Photoinitiatoren

KW - Thiol-Ene

KW - migrationsarm

KW - Photoinitiator

KW - Thiol-ene

KW - low Migration

M3 - Doctoral Thesis

ER -