PSt-b-PU-b-PSt copolymers using tetraphenylethane-urethane macroinitiator through SARA ATRP

Abstract

Abstract. The course of supplemental activator and reducing agent (SARA) atom transfer radical polymerization (ATRP) has been presented in the presence of Cu 0 . The novelty of this work is that SARA ATRP has been used for the first time to synthesize polystyrene-b-polyurethane-b-polystyrene copolymers by using tetraphenylethane-urethane macroinitiator as transitional products reacting with styrene in the presence of Cu II Br 2 /TPMA catalyst complex. The influence of copper surface area on the polymerization was examined. It was confirmed that in all cases, both the molecular weight of resulting copolymer increases linearly with increasing conversion as well as the value of ln([M] 0 /[M]) as a function of polymerization time increases linearly. A successful formation of the urethane-styrene copolymers was confirmed by NMR spectral studies.

Effect of polyhedral oligomeric silsesquioxane nanocage on the crystallization behavior of PEG 5k ‐ b ‐P(MA‐POSS) diblock copolymers achieved via atom transfer radical polymerization

“…Over the last several years, the ATRP has seen tremendous progress toward a “green” process by reducing the required concentration of the transition metal (Cu) concentration to parts per million (ppm). These developments include activators (Cu(I)) regenerated by electron transfer (ARGET) ATRP, initiators for continuous activator regeneration (ICAR) ATRP, supplemental activator and reducing agent (SARA) ATRP, electrochemically mediated ATRP (eATRP), and photochemically mediated ATRP …”

“…process by reducing the required concentration of the transition metal (Cu) concentration to parts per million (ppm). These developments include activators (Cu(I)) regenerated by electron transfer (ARGET) ATRP, [35,36] initiators for continuous activator regeneration (ICAR) ATRP, supplemental activator and reducing agent (SARA) ATRP, [37,38] electrochemically mediated ATRP (eATRP), [39] and photochemically mediated ATRP. [40,41] The first example of POSS-based well-defined block copolymers by ATRP was reported by Matyjaszewski's group, having poly(n-butyl acrylate) (P(nBA) middle block and poly(methacrylate-POSS) (P(MA-POSS).…”

Synthesis of inositol‐based star polymers through low ppm ATRP methods

“…[53][54][55][56][57][58][59] With the advent of methodologies to (re)generate active polymerization catalysts by reduction of deactive catalyst form, ATRP can be conducted at parts per million (ppm) levels of transition metal ( Fig. 1) using different reducing agents (organic as glucose, [60] phenols, [61] ascorbic acid, [62][63][64][65] hydrazine, [61] amines, [66,67] but also inorganic such as tin(II) 2-ethylhexanoate, [60] or zerovalent metal as Ag 0 [68,69] ) in activators regenerated by electron transfer (ARGET) approach, adding zerovalent metals (Cu 0 , Zn 0 , Mg 0 , or Fe 0 ) as supplemental activators and mild reducing agents (SARA), [70][71][72][73][74][75][76][77] and applying a reducing current as in electrochemically mediated ATRP. [11,74,[78][79][80][81][82][83][84][85][86][87][88][89][90][91][92]…”

Synthesis of naringin‐based polymer brushes via seATRP

“…ATRP is one of the most versatile and powerful technique that allow obtaining wide range of polymers with controlled composition, MW, MW distribution ( M w / M n , MWD, Ð ), and degrees of polymerization (DP) . Significant efforts have been dedicated to the development of the so‐called “green chemistry” class of this technique.…”

“…83,97,98 ATRP is one of the most versatile and powerful technique that allow obtaining wide range of polymers with controlled composition, MW, MW distribution (M w /M n , MWD, Ð), and degrees of polymerization (DP). 6,[99][100][101][102][103][104][105][106][107][108][109][110] Significant efforts have been dedicated to the development of the so-called "green chemistry" class of this technique. The catalyst concentration has been reduced to ppm level in the polymerization system, which resulted in the invention of the simplified electrochemically mediated ATRP (seATRP) approach, 51,52,[111][112][113][114][115][116][117][118] which offers more environmentally mild option by elimination of chemical reducing agents, generation of catalyst recycle possibility, and provides an option to receive polymers with narrow MWD.…”