Novel Amphiphilic Polyfluorene-Graft-(Polymethacrylic Acid) Brushes: Synthesis, Conformation, and Self-Assembly

Abstract

Novel polyfluorene polymer brushes with polymethacrylic acid side chains were obtained by atom transfer radical polymerization (ATRP) and activator generated by electron transfer (AGET) ATRP of tert-butyl methacrylate on polyfluorene multifunctional macroinitiator, followed by protonolysis of the tert-butyl groups of the side chains. Kinetics of polymerization and molecular weights were fully characterized. These polymer brushes luminesce in the blue region of the spectrum with high quantum yields (0.64–0.77). It was shown that the luminescence intensity of polymer brushes is higher than the luminescence intensity of the macroinitiator (0.61). Moreover, due to their amphiphilic nature, they can form unimolecular micelles when an alcohol solution of the polymer brush is injected into water. These properties can potentially be used in drug delivery and bioimaging.

Synthesis, Characterization, Conformation in Solution, and Thermoresponsiveness of Polymer Brushes of methoxy[oligo (propylene glycol)-block-oligo(ethylene glycol)]methacrylate and N-[3-(dimethylamino)propyl]methacrylamide Obtained via RAFT Polymerization

“…Similar behavior was previously observed in the homologous series of star-shaped four-armed poly-2-ethyl-2-oxazine [ 40 ]. Note that low values of A 0 ≤ 2.8, i.e., lower than the theoretically predicted value for a hard sphere, are typical for polymers with complex architecture, such as molecular brushes, as well as hyperbranched and star-shaped polymers [ 41 , 42 , 43 , 44 ].…”

Advances in design of polymer brush functionalized inorganic nanomaterials and their applications in biomedical arena

“…Surface‐initiated nitroxide‐mediated polymerization (SI‐NMP) (Chen et al, 2021; Park et al, 2021; Simonova et al, 2021) and photoiniferter‐mediated polymerization (SI‐PIMP) (Pan et al, 2016) are two other CRP approaches that have been utilized to create brushes of polymers through the grafting‐from strategy. Nitroxides (typically alkoxyamines) are used as mediators in SI‐NMP.…”

“…Poly(acrylic acid) (PAA), poly(methacrylic acid) (PMAA) (Chen et al, 2021; Hollingsworth & Larson, 2021; Simonova et al, 2021; Yu et al, 2020; Zhang et al, 2020), PDMAEMA (Ko et al, 2021; Lewoczko et al, 2021; Raynold et al, 2021), poly((diethylamino)ethyl methacrylate) (PDEAEMA) (Alotaibi et al, 2021; Beagan, Alghamdi, et al, 2020; Beagan, Lahmadi, et al, 2020), and poly(4‐vinylpyridine) (P4VP) are used as pH‐sensitive systems (Feng et al, 2019; Raczkowska et al, 2019; Zhang et al, 2018). The high swelling capacity accomplished in the saturated state of charge, normally ranging from 400% to 700% (Lego et al, 2010; Sanjuan et al, 2007) comes from positively or negatively charged monomers and concomitant osmotic pressure, which gives rise to durable intra‐ and interchain repulsive forces.…”

“…With the advent of nanotechnology, nanomaterials are becoming important to our daily life for their improved properties over bulk materials such as increased surface activity due to higher surface to volume ratio. These materials are becoming ever‐increasingly important in a plethora of applications in biomedical field, such as drug delivery systems (Gupta et al, 2019; Krasnopeeva et al, 2021; Li, Ahmed, et al, 2021; Li, Xu, et al, 2021; Parthipan et al, 2019; Simonova et al, 2021; Thomas et al, 2021), diagnosis (Chen, Shea, et al, 2017; Di Cio et al, 2017; Forinová et al, 2021; Liu et al, 2015; Yao et al, 2022), implants (Alves et al, 2020; Dhingra et al, 2021; Kolewe 2018; Oh et al, 2019; Xiao et al, 2020), and sensing (Liu et al, 2021; Oliveira et al, 2021; Sun et al, 2021). The main drawbacks of nanomaterials are their difficult synthesis routes, incompatibility with other materials, lack of stability, and tendency to form agglomerates.…”

“…Grafting, a covalent functionalization technique, is widely used for grafting various polymers or other materials onto the surface of NMs to produce polymer‐coated nanostructures which can be used for a large set of applications like sensing and drug delivery (Besford et al, 2021; Braga et al, 2021; Kim, Kwak, et al, 2020; Krasnopeeva et al, 2021; Oliveira et al, 2021; Simonova et al, 2021; Smook et al, 2020). Chemical grafting techniques can be divided into two broad classifications, namely the “grafting from” and “grafting onto” approaches (see Figure 1).…”