Highly efficient water‐soluble visible light photoinitiators. Issue 4 (5th October 2015)

• Record Type: Journal Article
• Authors: Benedikt, Stephan; Wang, Jieping; Markovic, Marica; Moszner, Norbert; Dietliker, Kurt; Ovsianikov, Aleksandr; Grützmacher, Hansjörg; Liska, Robert
• Is Part Of: Journal of polymer science. Volume 54:Issue 4(2016)
• Page Start: 473
• Page End: 479
• Publication Date: 2015-10-05
• Subjects: BAPO -- biocompatible -- cleavable -- Irgacure 2959 -- MAPO -- Norrish type I -- photoinitiator -- visible light -- water‐borne -- water‐soluble; 547
• DOI: 10.1002/pola.27903
• Languages: English
• ISSNs: 0887-624X

Abstract

ABSTRACT: The monoacylphosphineoxide (MAPO) saltsNa‐TPO andLi‐TPO and the bisacylphosphineoxide (BAPO) saltsBAPO‐ONa andBAPO‐OLi define an important and in the latter case a new class of water‐soluble photoinitiators (PIs) for radical polymerization. These compounds showed excellent water‐solubility of at least 29 g/L forNa‐TPO and up to 60 g/L forBAPO‐ONa in deionized water, thus exceeding the solubility of the state of the art PI for water‐based systems Irgacure 2959 (I2959 ) 6‐ to 12‐fold. However, biocompatibility, storage stability, and reactivity were equally important to replace the state of the art compounds. Concerning these properties, the MAPO and BAPO salts were at least in the same range (biocompatibility, stability) or showed even better results (reactivity) and had the additional advantage of visible light initiation.Na‐TPO andLi‐TPO achieved double bond conversions of an aqueous solution of N‐acryloylmorpholine over 97% with broad band irradiation (320–500 nm), Li‐TPO showed additionally very good biocompatibility (LC50 = 3.1 mmol/L) andBAPO‐OLi showed highest reactivity with visible light irradiation. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem.2016, 54, 473–479 Abstract : Environmentally friendly photocurable formulations are widely used for water‐borne coatings or hydrogel production for medicinal use. Currently there is a lack of suitable and commercially available photoinitiators with satisfying properties for such water‐based formulations. This article describes efficient compounds based on acylphosphine oxide salts for visible light curing. These salts provide excellent solubility in water, cytocompatibility, good storage stability, and high reactivity.