A New Protocol for Ash Wood Modification: Synthesis of Hydrophobic and Antibacterial Brushes from the Wood Surface

Abstract

The article presents the modification of ash wood via surface initiated activators regenerated by electron transfer atom transfer radical polymerization mediated by elemental silver (Ag0 SI-ARGET ATRP) at a diminished catalyst concentration. Ash wood is functionalized with poly(methyl methacrylate) (PMMA) and poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) to yield wood grafted with PMMA-b-PDMAEMA-Br copolymers with hydrophobic and antibacterial properties. Fourier transform infrared (FT-IR) spectroscopy confirmed the covalent incorporation of functional ATRP initiation sites and polymer chains into the wood structure. The polymerization kinetics was followed by the analysis of the polymer grown in solution from the sacrificial initiator by proton nuclear magnetic resonance (1H NMR) and gel permeation chromatography (GPC). The polymer layer covalently attached to the wood surface was observed by scanning electron microscopy (SEM). The hydrophobic properties of hybrid materials were confirmed by water contact angle measurements. Water and sodium chloride salt aqueous solution uptake tests confirmed a significant improvement in resistance to the absorption of wood samples after modification with polymers. Antibacterial tests revealed that wood-QPDMAEMA-Br, as well as wood-PMMA-b-QPDMAEMA-Br, exhibited higher antibacterial activity against Gram-positive bacteria (Staphylococcus aureus) in comparison with Gram-negative bacteria (Escherichia coli). The paper presents an economic concept with ecological aspects of improving wood properties, which gives great opportunities to use the proposed approach in the production of functional hybrid materials for industry and high quality sports equipment, and in furniture production.

Grafting of Multifunctional Polymer Brushes from a Glass Surface: Surface‐Initiated Atom Transfer Radical Polymerization as a Versatile Tool for Biomedical Materials Engineering

“…When the log reduction of CFU/mL counts greater than 2, it is considered as an antibacterial effect. [43,66,67] Thus, the results of glass-g-QPDMAEMA indicate its ability to inhibit the growth of Gram-positive S. aureus (2.15 log or 99.29% of effective bactericidal activity), but not Gram-negative E. coli (1.86 log and 98.61%). A higher value of the reduction of bacteria cell number was observed for glass-g-QPDMAEMA (99.29%) against S. aureus, which makes 0.007% of bacteria survive after 24 h contact with the tested glass.…”

From non-conventional ideas to multifunctional solvents inspired by green chemistry: fancy or sustainable macromolecular chemistry?

“…ATRP enables surface modification as well, resulting in smart materials created by grafting polymer brushes from various materials, such as wood, 77,[89][90][91][92] glass, [93][94][95] cellulose, 15,48,96-99 lignin 100 , or silicon wafers. 27,43,47,48,71,75,101 The minimization of reaction volume from millilitres to microliters is one of the factors under current development 43,73,75,102,103 as it both prevents waste and decreases the overall cost.…”

Recent Advances in Superhydrophobic Surfaces and Applications on Wood

“…This approach improves the stability of superhydrophobic surfaces and has good industrial prospects. In a study [ 35 ], ash wood was modified by regenerating surface initiating activators through electron transfer atom radical polymerization at low catalyst concentrations using elemental silver as a medium. The hydrophobic and antimicrobial properties of the wood were obtained by functionalizing ash wood with poly(methyl methacrylate) (PMMA) and poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA).…”