Polymer Chemistry Blog

Architecture effects on L-selectin shedding induced by polypeptide-based multivalent ligands: Polymers can be used as multivalent backbones to probe cell surface receptor arrangement and cell signalling. In this hot paper Shuang Liu and Kristi Kiick synthesize a series of polypeptide-based multivalent ligands and study the architecture effects on L-selectin shedding using by L-selectin shedding assay and ELISA. The team claim that these polypeptide-based multivalent ligands may have potential physiological and pathological applications as cell biology tools, and in the regulation of cell functions or inflammatory responses. (Polym. Chem., 2011, DOI: 10.1039/C1PY00063B, Advance Article)

Interested to know more? Why not read the full article available for free until 6^th June.

Researchers from Technion–Israel Institute of Technology have studied the kinetics of polymerization under confinement.

Experimental results show that the polymerisation kinetics are different inside a core–shell electrospun nanofibre compared to the bulk. The reaction rate decreases when the mean size of the clusters approaches the size of the internal fibre diameter. This causes the polymerisation reaction to become polychromatic, where the rate of reaction decreases with time.

Interested to know more? Why not read the full article for free: C. S. Reddy, A. Arinstein and E. Zussman, Polym. Chem., 2011, DOI: 10.1039/C0PY00285B (Advance Article)

Researchers from University of Florida have developed the first cathodically colouring yellow-to-transmissive switching electrochromic polymer.

Electrochromic displays require the modulation of three subtractive primary colours (red, yellow and blue or cyan, magenta and yellow) in order to express all of the colours in the spectrum. This work reports the first polymer that is yellow in its neutral state and highly transmissive in its oxidised state. The polymer achieves a 70% transmittance contrast at its absorption maximum and is capable of a full switch in under one second, therefore showing promise as a component of a full multicolour electrochromic device.

Interested to know more? Why not read the full article for free: C. M. Amb, J. A. Kerszulis, E. J. Thompson, A. L. Dyer and J. R. Reynolds, Polym. Chem., 2011, DOI: 10.1039/C0PY00405G (Advance Article)

Collaborative research from Hong Kong, Greece and China has investigated the flow of star polymers through nanopores.

Ultrafiltration of star chains with different lengths and numbers of arms shows that the minimum flow rate at which the chains begin to pass through a nanopore is independent of the arm length, but is strongly affected by the total number of arms and the number that initially enter the pore. These results are expected to influence the design of non-viral polymeric carriers for transporting genes into or through organs, such as the liver or kidneys.

Interested to know more? Why not read the full article for free:  H. Ge, S. Pispas and C. Wu, Polym. Chem., 2011, DOI: 10.1039/C0PY00361A (Advance Article)

Researchers from Princeton University and University of Connecticut have shown that 4,4′-diazidobiphenyl is an efficient photoactivatable crosslinker for polystyrene.

Crosslinking of the core of polystyrene-block-poly(ethylene oxide) copolymer nanoparticles was achieved by encapsulation of small molecule aryl diazides (4,4′-diazidobiphenyl) and subsequent photolysis. Nanoparticles modified in this way showed high thermal stability and have potential to be used as nanobeads for PCR. It was also found that 4,4′-diazidobiphenyl can confer solvent resistance to thin films of polystyrene.

Interested to know more? Why not read the full article for free: Siyan Zhang, Douglas H. Adamson, Robert K. Prud’homme and A. James Link, Polym. Chem., 2011, DOI: 10.1039/C0PY00350F (Advance Article)

A highly alternating polymer sequence of methacrylate and acrylate has been made via living radical polymerization by researchers from Kyoto University.

“Template monomers” – consisting of two polymerisable alkene functions, e.g. methacylate and acrylate, placed side-by-side at the 1 and 8 positions of a rigid naphthalene scaffold – were used to create highly alternating polymers. Metal catalysed living radical polymerisation of these “templates” gave linear, controlled polymers with no cross-linking.

Interested to know more? Why not read the full article for free: Yusuke Hibi, Shinsuke Tokuoka, Takaya Terashima, Makoto Ouchi and Mitsuo Sawamoto, Polym. Chem., 2011, 2, 341–347

This paper is part of an Emerging Investigators themed issue of Polymer Chemistry. Please click here to read the full listing of papers.

A novel initiation strategy for enzyme-induced radical polymerization using alkyl halides has been developed by researchers from the Agency of Science, Technology and Research, Singapore.

This approach can be used in both emulsion polymerisation and surface-initiated polymerisation. It is possible to tune the molecular weights of polymers reversibly (with 2-cyano-2-propyl dithiobenzoate) or irreversibly (with L-cysteine) through the selection of the appropriate chain transfer agent.

Interested to know more? Why not read the full article for free: Yeap-Hung Ng, Fabio di Lena and Christina L. L. Chai, Polym. Chem., 2011, DOI: 10.1039/C0PY00139B (Advance Article)

Chinese scientists have developed a new way to fabricate polymeric vesicles with well-defined PMMA brushes using silica particles as templates by surface-initiated photopolymerization (SIPP).

A cross-linked layer of PDMAEMA was immobilised on the surface of silica particles before photo-initiated polymerisation of methyl methacrylate in the presence of thioxanthone generated PMMA brushes on the vesicles. Removal of the silica cores yielded polymeric vesicles with well-defined PMMA brushes. This robust approach shows great potential for the fabrication and modification of polymer vesicles with differerent sizes and functions.

Interested to know more? Why not read the full article for free:  Fengting Chen, Xuesong Jiang, Rui Liu and Jie Yin, Polym. Chem., 2011, DOI: 10.1039/C0PY00288G (Advance Article)