Copolymerization of styrene and methyl methacrylate mediated by iron wire/N,N,N0 ,N0 -tetramethyl-1,2-ethanediamine as catalyst in the presence of air Guo-Xiang Wang • Mang Lu • Jing Li • Li-Chao Liu • Bei-Ping Luo • Hu Wu • Ming Zhong
Received: 6 May 2012 / Accepted: 18 November 2012 Ó The Author(s) 2012. This article is published with open access at Springerlink.com
Abstract Random copolymers of P(MMA-co-styrene) were synthesized via single electron transfer-living radical polymerization (SET LRP) at 25 °C in N,N-dimethylformamide (DMF) and benzene using CCl4 as initiator and Fe(0) wire/N,N,N0 ,N0 -tetramethyl-1,2-ethanediamine (TMEDA)/ hydrazine (NH2NH2) complexes as catalyst in the presence of air. Fe(0) wire-mediated single electron transfer-living radical copolymerization of MMA and styrene represented a robust and versatile technique to synthesize the welldeﬁned copolymers. The copolymerization rate was faster in DMF than in benzene, as determined by the apparent rate constants. The results showed that the copolymerization followed ﬁrst-order kinetics model in the presence of polar DMF and non-polar benzene. The molecular weights increased linearly with the increase of monomer conversion with a narrow polydispersity index when the conversion was beyond 25 %. The polarity and the quantity of solvent had signiﬁcant effects on the polymerization, and the apparent rate constants were 1.28 9 10-4, 1.21 9 10-4, and 9.23 9 10-5 s-1 in the order of DMF amount, 5, 10, and 15 mL. The conversion increased from 29.3 to 48.5 % and the polydispersity index (PDI) changed from G.-X. Wang (&) Á L.-C. Liu Á B.-P. Luo Á H. Wu Á M. Zhong College of Chemistry and Chemical Engineering, Hunan Institute of Science and Technology, Yueyang 414006, Hunan, People’s Republic of China e-mail: email@example.com M. Lu School of Materials Science and Engineering, Jingdezhen Ceramic Institute, Jingdezhen 333403, Jiangxi, People’s Republic of China J. Li Tianjin Entry-Exit Inspection and Quarantine Bureau, 300201 Tianjin, People’s Republic of China
1.24 to 1.21 with [CCl4]0/[TMEDA]0 molar ratio changing from 1:0.5 to 1:5. The chain extension experiment demonstrated that the copolymerization exhibited a living characteristic. Keywords Styrene Á Methyl methacrylate Á Living polymerization Á Single electron transfer-living radical copolymerization Á TMEDA
Introduction Over the past decades, a number of controlled/living radical polymerization methods have been developed and the three most promising types are: atom transfer radical polymerization (ATRP), stable free radical polymerization (SFRP), and reversible addition-fragmentation chain transfer (RAFT) polymerization. Among them, ATRP has rapidly attracted growing interest because of its versatility in the synthesis of polymers with predictable molecular weights, low polydispersities, and speciﬁc functionalities [1, 2]. In ATRP, an equilibrium is established between the dormant species and the active propagating radicals mediated by metal complexes. However, normal ATRP has some limits, such as water- and oxygen-free systems. Therefore, some improved ATRP techniques have been developed, for example, reverse ATRP (RATRP) [3, 4], initiators for continuous activator regenerated by electron transfer ATRP (ICAR ATRP) [5, 6], simultaneous reverse and normal initiation (SRNI ATRP) , activators generated by electron transfer ATRP (AGET ATRP) [8, 9], activators regenerated by electron transfer ATRP (ARGET ATRP) [10, 11] and single electron transfer-living radical polymerization (SET LRP) [12–14]. SET LRP was ﬁrst investigated by Percec et al. . SET LRP technique has Iran Polymer and Petrochemical Institute
Iran Polym J
numerous advantages in synthesizing well-deﬁned polymers with narrow molecular weight distribution at ambient temperature and in friendly solvent. In a short time, since its appearance, SET LRP has...