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A new type of asymmetric chirogenic polymerization by asymmetric allylic substitution catalyzed by planar–chiral ruthenium complexes was designed. The polymerization systems function in a highly stereoselective manner. The asymmetric carbon in the main chain is precisely controlled. Each monomer unit of the polymer has a potentially reactive terminal olefin, which can be used for further transformations, ring-closing metathesis and thiol–ene reaction. Additionally, the resulting polymer can be transformed poly “arylopeptide”, through reductive cleavage of the N–O bond in N-alkoxyamide, which adopts a one-handed stable helical conformation in solution.
Tommykaira ZZ with Teijin’s PC pillar-less front window. The world’s first PC pillar-less front window was developed by using Teijin’s polymer material engineering, injection press and hard coating technologies. These technologies can overcome issues for plastic glazing, such as scale up and long-term reliability and provide low optical distortion window and much higher scratch and weather resistance compared to plastic glazing in the market. These technologies can also contribute to driver’s safety and provide more enjoyable sightseeing. Teijin aims to be a total solution provider for automobile manufacturers.
We synthesized poly(bisphenol A-co-ephichlorohydrin)–titanium phosphonate clusters (Ti4P3: [Ti4(μ3-O)(OiPr)5(μ-OiPr)3(O3PPh)3]·thf; Ti4P4: [Ti(OiPr)(acac)(O3PPh)]4; Ti7P6: Ti7(μ3-O)2 (OiPr)6(μ-OiPr)6(O3PBnBr)6). From the result of swelling test using tetrahydrofuran, Ti7P6 cluster showed highest cross-linking efficiency.
Controlled cationic cyclopolymerizations of divinyl ethers with cyclohexene, norbornene, norbornane, cyclic acetal, or adamantane moiety were carried out. High-molecular-weight star-shaped cyclopolymers were synthesized by the reaction of the formed living cyclopolymers with a small amount of divinyl ether crosslinking agent. Glass transition temperatures (Tg’s) of both the cyclopolymers and star-shaped cyclopolymers were as high as 145−229 oC. Methacrylate-terminated end-functionalized star-shaped cyclopolymers were synthesized by the functionalized initiator-based living cationic cyclopolymerization of divinyl ethers followed by the chain linking reactions among the formed living cyclopolymers with divinyl ether crosslinker. The obtained end-functionalized star-shaped cyclopolymers were subjected to thermal crosslinking reaction to give star-shaped cyclopolymer networks with film-forming ability.
Polypeptides containing periodic aromatic residues, 4-aminobenzoic acid (Abz), in their main chains were synthesized via papain-catalyzed chemoenzymatic polymerization of tripeptide ester monomers under moderate conditions in aqueous buffers. The secondary structures of the Abz-containing polypeptides were investigated by IR and wide-angle X-ray diffraction analysis. The WAXD profile of poly(GlyAbzGly) was similar to that of polyGly, whereas poly(AlaAbzAla) adopted a sheet-like structure similar to the β-sheet of polyAla.
The block glycopolymers with specific arrangement of sugar ligand and electric charges were synthesized via RAFT living radical polymerization, where the block polymers were efficiently obtained using two orthogonal reactions of Huisgen and thiol-epoxy ring opening reactions. The molecular recognition abilities of the block glycopolymers was examined.