Herein the concept of tandem postpolymerization modification as a versatile route to synthesize well-defined, highly functionalized polymers is introduced. Poly(pentafluorophenyl methacrylate) obtained by atom transfer radical polymerization was first modified with allylamine, which displaces the active ester to give well-defined polymers with pendant alkene groups, which are difficult to obtain by direct (radical) polymerization of allylic-functional monomers. The produced poly(allylmethacrylamide) was modified by a second postpolymerization modification reaction with a thiol-terminated peptide (CVPGVG) using AIBN as the radical source. NMR, IR, and SEC demonstrated successful conjugation onto the polymer to give a polymer-peptide hybrid material. This versatile strategy should extend the scope of controlled radical polymerization and "click"-type reactions.
Preparation of an amphiphilic block copolymer (Am-BCP) based on poly(ethylene glycol) methyl ether methacrylate (PEGMA) and heptafluorobutyl acrylate (HFBA) via RAFT polymerization and application of this Am-BCP as surf-RAFT agent for polymerization of styrene.
This investigation reports the synthesis of poly(methyl methacrylate) via activators regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP) and studies the effect of solvents and temperature on its polymerization kinetics. ARGET ATRP of methyl methacrylate (MMA) was carried out in different solvents and at different temperatures using CuBr 2 as catalyst in combination with N,N,N ′ ,N ″ ,N ″ -pentamethyldiethylenetriamine as a ligand. Methyl 2-chloro propionate was used as ATRP initiator and ascorbic acid was used as a reducing agent in the ARGET ATRP of MMA. The conversion was measured gravimetrically. The semilogarithmic plot of monomer conversion versus time was found to be linear, indicating that the polymerization follows first-order kinetics. The linear polymerization kinetic plot also indicates the controlled nature of the polymerization. N,N-Dimethylformamide (DMF), tetrahydrofuran (THF), toluene, and methyl ethyl ketone were used as solvents to study the effect on the polymerization kinetics. The effect of temperature on the kinetics of the polymerization was also studied at various temperatures. It has been observed that polymerization followed first-order kinetics in every case. The rate of polymerization was found to be highest (k app = 6.94 × 10 −3 min −1 ) at a fixed temperature when DMF was used as solvent. Activation energies for ARGET ATRP of MMA were also calculated using the Arrhenius equation.
K E Y W O R D Satom transfer radical polymerization, kinetics, methyl methacrylate, solvent effect
Copolymerization is an important synthetic tool to prepare polymers with desirable combination of properties which are difficult to achieve from the different homopolymers concerned. This investigation reports the copolymerization of 2-ethylhexyl acrylate (EHA) and styrene using copper bromide (CuBr) as catalyst in combination with N,N,N′,N″,N″- pentamethyldiethylenetriamine (PMDETA) as ligand and 1-phenylethyl bromide (PEBr) as initiator. Linear kinetic plot and linear increase in molecular weights vs. conversion indicate that copolymerization reactions were controlled. The copolymer composition was calculated using 1H NMR studies. The reactivity ratio of styrene and EHA (r1 and r2) were determined using the Finemann–Ross (FR), inverted Finemann–Ross (IFR), and Kelen–Tudos (KT) methods. Thermal properties of the copolymers were also studied by using TGA and DSC analysis.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.