Novel Cationic RAFT‐Mediated Polystyrene/Clay Nanocomposites: Synthesis, Characterization, and Thermal Stability

Abstract

Two novel cationic RAFT agents, PCDBAB and DCTBAB, were anchored onto MMT clay to yield RAFT‐MMT clays. The RAFT‐MMT clays were then dispersed in styrene where thermal self‐initiation polymerization of styrene to give rise to exfoliated PS/clay nanocomposites occurred. The RAFT agents anchored onto the clay layers successfully controlled the polymerization process resulting in controlled molecular masses and narrow polydispersity indices. The nanocomposites prepared showed enhanced thermal stability, which was a function of the clay loading, clay morphology, and slightly on molecular mass.magnified image

Living Radical Polymerization by the RAFT Process - A Second Update

“…iBA [223] St [223,224] 385 [104] 388 [104] 389 [104] (Continued) MAA [225] MAA-b-St [225] S Br Ϫ ϩ S N 64 [226,227] St [226] S S Si(OCH 3 ) 3…”

“…tBA [283] 162 [339] S S C 4 H 9 S -C 163 [339] S S Ph N N N C 4 H 9 S BA [339] St [339] 164 [348] S S C 3 H 7 S MA [349] 165 [350] St [350] St-b-MA [350] 166 [351] S S C 4 H 9 S (BA) [351] (St) [351] (St-b-BA) [351] (BA-b-St) [351] 167 [337] S S C 6 H 13 S St [337] 168* [352] S S C 12 H 25 S 319 [352] (Continued) [283] St [283,353] 170 [283] S S S HO 2 C AA [354] DMAM [218] NIPAM [355] St [218,283] (St) [356] (SSO3Na) [167] DADMAC [357] 346 [358] AA-b-SSO3Na [354] 346-b-DMAM [358] (St-b-DMAM) [218] 171 [349] MA [349] MA-b-St [349] 172 [226] S S Br Ϫ N C 12 H 25 S ϩ St [226] 173 [227] 176 [350,360] POSS macro-RAFT agent…”

In situ Synthesis of Polymer/Clay Nanocomposites by Living and Controlled/Living Polymerization

“…Later, Zhang et al [25] used the in situ RAFT polymerization with an intercalated RAFT agent to produce polystyrene/MMT nanocomposites with exfoliated structure and higher thermal stability compared to pure polystyrene. Hartmann et al [45,46] have also shown the effectiveness of intercalated RAFT agents on the control of polymerization in bulk and miniemulsion during PCNs synthesis. The effect of clay loadings for the preparation of nanocomposites has been reported by Ding et al [26] who found exfoliated or intercalated structures, based on the different clay loadings.…”

Surface‐Initiated Reversible Addition Fragmentation Chain Transfer (RAFT) Polymerization of Styrene from Laponite Clay Surfaces

“…[3,[12][13][14][15] Mathias [16] and Bourgeat-Lami [17] are known to have the first reports on SI-ATRP and SI-NMP carried out on Laponite clay. Laponite clay is composed of platelets with a uniform size of 25 nm and has since attracted a lot of attention in both industry and academia.…”