Molecular dynamics simulations of the folding structure of a thermoresponsive 2-dimethylaminoethyl methacrylate oligomer in the globule state

Molecular dynamics simulations of the folding structure of a thermoresponsive 2-dimethylaminoethyl methacrylate oligomer in the globule state

A ‘core-shell’ globular structure of a 2-dimethylaminoethyl methacrylate oligomer was formed in aqueous solutions. 



  • Submicron-sized SiO2/Al2O3(Si/Al)-coated titanium dioxide (Si/Al-TiO2) particles were encapsulated through the emulsion copolymerization of methacrylates using a thermoresponsive polymerizable nonionic surfactant, NE-10. An optimized water-dispersion method was developed to disperse Si/Al-TiO2 dried powders using an ultrasonic homogenizer, a paint shaker, and a pot mill rotator in the presence of partially neutralized poly(isobutylene-alt-maleic acid). The encapsulation efficiency (Fen) was affected by the monomer and initiator types, NE-10, and sodium dodecyl sulfonate concentrations. Fen > 90% was achieved by a two-step semibatch emulsion copolymerization under optimized conditions.

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    • Seigou Kawaguchi
    Original Article
  • Three types of aromatic polyketones bearing tetrakis(nonafluorobutyl)-pterphenylene units were successfully synthesized via nucleophilic aromatic substitution polymerization. In particular, high-molecular-weight polymers were obtained in DMAc. These polymers have water and oil repellency, good thermal stability, and excellent solubility in typical organic solvents such as MEK, THF, CHCl3, and DMAc.

    • Haruki Konta
    • Katsuya Maeyama
    Original Article
  • The feasibility of using strongly electron-deficient naphthobispyrazine bisimide (NPI) as a building unit for n-type semiconducting polymers used in all-polymer organic photovoltaics (OPV) cells was investigated. The NPI-based polymers had sufficiently deep LUMO energy levels of ~−3.7 eV and narrow bandgaps of less than 1.5 eV, which matched well energetically with p-type polymers exhibiting wide optical bandgaps. The NPI-based polymers exhibited a clear photoresponse in all-polymer OPV cells blended with PTB7-Th as a benchmark p-type polymer and showed power conversion efficiencies of up to 1.6%.

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    • Yuka Iwasaki
    • Itaru Osaka
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    • Hyo Jo Jeong
    • Jung Yun Do
    Original Article
  • During bulk polymerization, the relative concentration of monomer and polymer changes. When the monomer is liquid and the obtained polymer is a glassy solid, vitrification occurs at some point of the reaction. Herein, we investigate the bulk polymerization of methyl methacrylate, ethyl methacrylate, and butyl methacrylate. We show that, at the vicinity of vitrification, the reaction solution becomes heterogeneous, which results in an apparent phase separation. We discuss polymerization-induced vitrification in conjunction with reaction acceleration (the Trommsdorff effect) and subsequent deceleration (the glass effect).

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    • Ryutaro Mishima
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  • A novel substituted phenylacetylene with a pendant betulin derivative group was designed and synthesized successfully, The obtained monomer was further polymerized in an achiral catalytic system, and polymer exhibited a strong Cotton effect at the main-chain absorption regions in the circular dichroism spectra. The helical porous material polyphenylacetylene grafted onto the natural product lupane triterpene as a side group exhibits a set of valuable properties with excellent thermal stability, solubility and membrane-forming ability.

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    • Jiaxiang Wen
    • Takashi Kaneko
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  • PLLA exhibits excellent biocompatibility and biodegradability, but its poor hydrophilicity causes less cell adhesion. To address this issue, the bioactive peptide scaffold was synthesized by PLLA fiber substrate modified with an IKVAV peptide and following heat treatment at 60 °C for regulation of cell adhesive. This scaffold has the potential to serve as an in vitro model for investigating the effect of the ECM on glioblastoma multiforme cells and tumor metastasis in white matter tracts.

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    • Akihisa Otaka
    • Tetsuji Yamaoka
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  • Polytetrafluoroethylene (PTFE) has widely been used in essential daily items and biomedical materials. The application range of PTFE should be greatly expanded if it can be flexibly functionalized. However, the functionalization method is still limited. In this study, peptides with affinity to PTFE were identified through affinity-based selection from a phage-displayed peptide library. The peptides had potential as a molecular glue to immobilize functional proteins and biomolecular assemblies, i.e., phages, onto PTFE films.

    • Yuichi Kida
    • Toshiki Sawada
    • Takeshi Serizawa