Work

Self-Anchoring Coumarin Oxime Ester Photoinitiators with Low Migration for UV-LED Curable Coatings

Year: 2024

Type: article

Abstract: Reducing photoinitiator migration from photocured coatings remains a critical challenge, particularly for applications in food packaging and healthcare products. Here, we report a series of novel UV-LED sensitive oxime ester photoinitiators that possess self-anchoring ability through incorporating polymerizable double bonds into the coumarin chromophore. All photoinitiators exhibit strong absorption around 340 nm and efficient photolysis under 365 nm LED irradiation, showing good initiating efficiency in acrylates and thiol-ene formulations. Migration studies show that the incorporation of polymerizable groups at the oxime ester terminus reduces the migration rate of the residual photoinitiator from 81% to 16.3%, while introducing an allyl group into the coumarin structure further decreases it to 5% and potentially suppresses the migration of low-molecular-weight photolysis products. The dual-functionalized derivative achieves the lowest migration rate of 3%. This molecular design strategy provides an effective approach toward safe UV-LED curable coatings with minimal photoinitiator migration.

Source: Coatings

DOI: 10.3390/coatings15010006

Authors: Zhihong Chen, Pin Yang, Huaqiao Lu, Shiyun Xiong, Gaole Dai, Zhiquan Li

Institutions: Guangdong University of Technology, Jiangnan University, Hangzhou Normal University

Language: English

Topic: Photopolymerization techniques and applications

Subfield: Organic Chemistry

Field: Chemistry

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,955

Funder: Natural Science Foundation of Guangdong Province