Sulfur-containing polymer supported palladium nanoparticles (Pd/SPMB) were prepared by using the crosslinked poly(N,N′-methylene bis(acrylamide)) (SPMB) as the platform. The SPMB was synthesized via the reversible addition−fragmentation chain transfer (RAFT) polymerization, from which the sulfur inherently exists in the RAFT polymer due to the use of thiocarbonate as the chain transfer agent, and could be further utilized as a modifier of Pd nanoparticles. The Pd/SPMB showed size-dependent activity and selectivity in the semihydrogenation of alkynes to alkenes. The catalyst with an average Pd size of 5.3 nm was active in the semihydrogenation of both internal and terminal alkynes. Most of the surface of Pd NPs was covered (or poisoned) by sulfide and thiolate due to the moderate complexation strength between Pd NPs and SPMB, thus leading to the selectivity enhancement toward alkene. Furthermore, the catalyst was highly stable and can be reused 10 times without an appreciable loss in either activity or selectivity.

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A series of novel hyperbranched poly[2-(α-d-mannopyranosyloxy) ethyl methacrylate-co-N,N’-methylenebisacrylamide] (HPManEMA-co-MBA) are synthesized via a reversible addition fragmentation polymerization (RAFT). The dosage ratios of linear and branch units are tuned to obtain different degree of branching (DB) in hyperbranched glycopolymers. The DB values are calculated according to the content of nitrogen, which are facilely determined by elemental analysis. The lectin-binding properties of HPManEMA-co-MBA to concanavalin A (ConA) are examined using a turbidimetric assay. The influence of defined DB value and molecular weight of HPManEMA-co-MBA on the clustering rate is studied. Notably, HPManEMA-co-MBAs display a low cytotoxicity in the MTT assay, thus are potential candidates for biomedical applications.

A novel fluorescent HPEAM-TPEAH, possessing a highly selective and sensitive response to Zn2+, was synthesized using RAFT.