Synthesis of Poly(methacrylic acid) Brushes via Surface-Initiated Atom Transfer Radical Polymerization of Sodium Methacrylate and Their Use as Substrates for the Mineralization of Calcium Carbonate

Abstract

This manuscript describes the synthesis of poly(methacrylic acid) (PMAA) brushes via surfaceinitiated atom transfer radical polymerization (SI-ATRP) of sodium methacrylate (NaMA) and their use as substrates for the mineralization of calcium carbonate. A CuBr/CuBr 2 /bipyridine catalyst system in aqueous solution at room temperature allowed the synthesis of brushes with thicknesses of up to 300 nm. Using substrates modified with mixtures of an ATRP-initiator modified trimethoxysilane and an "inert" pivaloyl-modified trimethoxysilane to initiate the ATRP of NaMA, a series of brushes with varying chain density could be prepared. Subsequent mineralization experiments revealed that, while low-density brushes promoted the formation of calcite crystals, high-density brushes were covered with a thin layer of amorphous CaCO 3 (ACC). This is of interest because ACC can serve as a metastable precursor for different crystalline CaCO 3 polymorphs and offers attractive perspectives for the bottom-up fabrication of well-defined CaCO 3 crystal architectures.

From Self-Assembled Monolayers to Coatings: Advances in the Synthesis and Nanobio Applications of Polymer Brushes

“…Most often XPS is used to confirm brush growth, to study surface chemical composition of the brush and to determine surface densities of bound molecules on the brush [138][139][140][141][142]. XPS has also been used for initiator-coated surfaces, however most of these studies have been limited to qualitative confirmation of the presence of initiator groups [143][144][145][146].…”

Improving the Stability in Aqueous Media of Polymer Brushes Grafted from Silicon Oxide Substrates by Surface‐Initiated Atom Transfer Radical Polymerization

“…[13] PMAA brushes were synthesized by combining two published protocols. [20,21] In detail, 41 mg (0.18 mmol) copper(II) bromide, 300 mL (1.1 mmol) HMTETA and water (4.5 mL) were premixed in a Schlenk tube and degassed by two freeze/pump/thaw cycles after which 45 mg (0.3 mmol) copper(I) bromide was added under nitrogen. At the same time, in another Schlenk tube, 9.3 g NaMA (89 mmol) was mixed with deionized water (10 mL), stirred until complete solubilization and degassed in the same way as the previous mixture.…”

Stable Poly(methacrylic acid) Brush Decorated Silica Nano-Particles by ARGET ATRP for Bioconjugation

“…ARGET ATRP of t-BMA was then performed from the surface initiator decorated Si-NP using CuCl2 and tris-((2-pyridyl)-methyl)-amine (TPMA) as the catalytic system, and tin(II)-2-ethylhexanoate as the reducing agent [24]. While it has been shown that direct ATRP of sodium methacrylate is possible from surfaces [38], it was decided to employ the protected monomer as that would avoid using an aqueous medium and potential hydrolysis of the particles under the reaction conditions. The polymerizations were carried out in the presence of a defined amount of free sacrificial initiator (methyl-2-bromopropionate) to mediate the reaction kinetics as well as the molecular weight of the polymer brushes [35].…”