Synthesis of telechelic C₆₀ end‐capped polymers under microwave irradiation

Abstract

Bromo-Double-Terminated polystyrene (BrPSt-Br) and poly(methyl methacrylate) (Br-PMMA-Br) with predesigned molecular weight and narrow polydispersity were prepared by atom transfer radical polymerization (ATRP) using the initiating system aaЈ-dibromo-p-xylene(DBX) / CuBr/2,2Ј-bipyridine(bipy). The precursor bromo-terminated polymers were subsequently functionalized with fullerene C 60 using CuBr/bipy as the catalyst system under microwave irradiation (MI). The telechelic C 60 endcapped products were characterized by gel permeation chromatography (GPC), UV-vis, FT-IR, TGA, DSC, 1 H NMR, and 13 C NMR. The results showed that microwave irradiation could significantly increase the rate of fullerenation reaction, and the physical properties and structure of the C 60 endcapped polymers are not modified by the use of the microwave.

Preparation and characterization of a polycaprolactone/C60 composite and its improved counterpart (PCLNH2/C60OH)

“…Figure 5 shows the results of 13 C-NMR used to examine the structure of PCL, PCLANH 2 , and PCLANH 2 /C 60 AOH to further confirm the grafting previously proposed. For the pure PCL [ Fig.…”

“…This washing was repeated three times, and the powder was then washed for further three times with methanol (99%; Aldrich) and dried under primary vacuum for 24 h at 105 C. It was then purified by dissolving in HCl solution (0.2M). This acid solution was neutralized by adding NaOH solution (1M) (adjusted to pH [12][13]. At this stage, no precipitation occurred.…”

“…Recently, various methods have been introduced for functionalizing C 60 to improve its compatibility with monomers and polymers. 12,13 Of these methods, most involve oxidation of the surfaces of C 60 , [14][15][16] such as oxidation of C 60 in a mixture of sulfuric and nitric acids or by treatment with piranha (sulfuric acid/hydrogen peroxide). In a mixture of strong oxidizing acids such as HNO 3 or H 2 SO 4 , 10,17,18 C 60 can be functionalized with carboxyls or quinines.…”

One Decade of Microwave‐Assisted Polymerizations: Quo vadis?

“…[167] The reaction was performed in a modified domestic microwave oven and reported to be accelerated by a factor of %25, yielding modified polymers with properties comparable to those of polymers modified under CH. Cai and coworkers investigated also the fullerenation of poly(carbonate) (PC) from the direct reaction of PC and C 60 with AIBN in 1,1,2,2-tetrachloroethane under reflux conditions in a modified domestic microwave oven.…”

Green Polymer Synthesis: An Overview on Use of Microwave‐Irradiation

“…Compared with the conventional heating process, MW could significantly enhance the rate of the fullerenation under identical reaction conditions [218]. The C60 end-capped polymers were obtained with the bromo double-terminated polymers were obtained from the ATRP of styrene and MMA using á,á-dibromo-p-xylene under MW irradiation [219,220]. The same authors presented the MW-assisted synthesis of cross-linked poly(vinyl alcohol) nanocomposites comprising single-walled carbon nanotubes, multi-walled carbon nanotubes, and fullerenes [221].…”