TY - JOUR

T1 - Surface-Initiated Polymerizations Mediated by Novel Germanium-Based Photoinitiators

AU - Müller, Matthias

AU - Drusgala, Manfred

AU - Fischer, Roland C.

AU - Torvisco, Ana

AU - Kern, Wolfgang

AU - Haas, Michael

AU - Bandl, Christine

N1 - Publisher Copyright: © 2023 The Authors. Published by American Chemical Society.

PY - 2023/6/23

Y1 - 2023/6/23

N2 - Since surface-initiated photopolymerization techniques have gained increasing interest within the last decades, the coupling of photoinitiators to surfaces and particles has become an important research topic in material and surface sciences. In terms of surface modification and functionalization, covalently coupled photoinitiators and subsequent photopolymerizations are employed to provide a huge variety of surface properties, such as wettability, stimulus responsive features, antifouling behavior, protein binding, friction control, drug delivery, and many more. For this purpose, numerous type I and type II photoinitiators or other photosensitive moieties have been attached to different substrates so far. In our studies, a convenient and straightforward synthetic protocol to prepare a novel germanium-based photoinitiator (bromo-tris(2,4,6-trimethylbenzoyl)germane) in good yields was developed. The immobilization of this photoinitiator at the surface of silicon wafers and quartz plates was evidenced by X-ray photoelectron spectroscopy (XPS). Employing visible-light-triggered surface-initiated polymerization of different functional monomers, including acrylamide, perfluorodecyl acrylate, and fluorescein-o-acrylate, surfaces with various features such as hydrophilic/hydrophobic and fluorescent properties were prepared. This was also achieved in a spatially resolved manner. The polymer layers were characterized by contact angle measurements, UV–vis/fluorescence spectroscopy, spectroscopic ellipsometry, and XPS. The thicknesses of the surface grafted polymer layers ranged between 10 and 126 nm.

AB - Since surface-initiated photopolymerization techniques have gained increasing interest within the last decades, the coupling of photoinitiators to surfaces and particles has become an important research topic in material and surface sciences. In terms of surface modification and functionalization, covalently coupled photoinitiators and subsequent photopolymerizations are employed to provide a huge variety of surface properties, such as wettability, stimulus responsive features, antifouling behavior, protein binding, friction control, drug delivery, and many more. For this purpose, numerous type I and type II photoinitiators or other photosensitive moieties have been attached to different substrates so far. In our studies, a convenient and straightforward synthetic protocol to prepare a novel germanium-based photoinitiator (bromo-tris(2,4,6-trimethylbenzoyl)germane) in good yields was developed. The immobilization of this photoinitiator at the surface of silicon wafers and quartz plates was evidenced by X-ray photoelectron spectroscopy (XPS). Employing visible-light-triggered surface-initiated polymerization of different functional monomers, including acrylamide, perfluorodecyl acrylate, and fluorescein-o-acrylate, surfaces with various features such as hydrophilic/hydrophobic and fluorescent properties were prepared. This was also achieved in a spatially resolved manner. The polymer layers were characterized by contact angle measurements, UV–vis/fluorescence spectroscopy, spectroscopic ellipsometry, and XPS. The thicknesses of the surface grafted polymer layers ranged between 10 and 126 nm.

KW - acylgermanes

KW - grafting from reaction

KW - photoinitiator immobilization

KW - photopolymerization

KW - surface modification

KW - surface-initiated polymerization

UR - http://www.scopus.com/inward/record.url?scp=85164241507&partnerID=8YFLogxK

U2 - 10.1021/acsami.3c05528

DO - 10.1021/acsami.3c05528

M3 - Article

C2 - 37350334

AN - SCOPUS:85164241507

VL - 15.2023

SP - 31836

EP - 31848

JO - ACS Applied Materials and Interfaces

JF - ACS Applied Materials and Interfaces

SN - 1944-8244

IS - 26

ER -