Preparation of hierarchical porous carbons from amphiphilic poly(vinylidene chloride-co-methyl acrylate)-b-poly(acrylic acid) copolymers by self-templating and one-step carbonization method

Abstract

Based on our previous proposed method to fabricate the hierarchical porous carbons (HPCs), a series of amphiphilic poly(vinylidene chloride-co-methyl acryalte)-b-poly(acrylic acid) (PVDC-b-PAA) copolymers were prepared via RAFT polymerization and used to prepare the HPCs by self-templating and one-step carbonization method. The phase structure and thermal degradation behavior of PVDC-b-PAA copolymers, as well as the morphology and pore structure of corresponding carbons were investigated. It was found that all block copolymers exhibited micro-phase separation feature and showed the PAA-dispersed, bi-continuous, and PAA-dominated phase structures as the PVDC/PAA molar ratio varied from 3:1 to 0.77:1. Although the PVDC-b-PAA copolymers exhibited the individual glass transitions of each block, the thermal degradations of PVDC and PAA blocks were interacted and overlapped. The carbons prepared from PVDC-b-PAA contained the micro- and meso-pores, which were mainly originated from the thermal degradation of PVDC segment and the pyrolysis of PAA segment, respectively. The carbons prepared from PVDC66-b-PAA22 copolymer exhibited a maximum Brunauer–Emmett–Teller surface area of 1093m2g−1 and a maximum total pore volume of 0.51cm3g−1. Due to the incomplete pyrolysis of PAA segment and the jamming effect to pores caused by the PAA-based carbon, the total pore volume of HPCs prepared from PVDC-b-PAA copolymers were lower than that of HPCs prepared from the PVDC-b-polystyrene copolymers (J. Mater. Sci. 49 (2014) 1090–1098).