A bio-based hydroxyl group-containing diene monomer, silyl-protected β-myrcenol (MyrOSi), is introduced to the field of carbanionic polymerization. Polymerization in cyclohexane, using sec-butyllithium as an initiator, resulted in homopolymers with well-controlled molecular weights in the range of 7.9−31.3 kg mol −1 and dispersities between 1.10 and 1.27. The silyl protective groups can be removed quantitatively under mild conditions, using tetra-n-butylammonium fluoride (TBAF), resulting in well-defined polymyrcenol. The statistical copolymerization of MyrOSi with β-myrcene was also investigated. The monomer sequence distribution of the copolymers was evaluated by 1 H NMR kinetic studies. Random copolymerization was observed for β-myrcene/MyrOSi copolymerization. Copolymers with varying MyrOH content, in the full range between 0 and 100 mol% MyrOH, were synthesized (Đ ≤ 1.11) and characterized with regard to their glass−transition temperatures and the polydiene microstructure. With an increasing MyrOH content in the polymer backbone, an increase in the number of 3,4-units was observed, resulting in an increase in T g from −67 to −23 °C. The P(Myr-co-MyrOH) copolymers are valuable building blocks for the synthesis of more complex polymer architectures, such as graft copolymers. The P(Myr-co-MyrOH) copolymers were used for the synthesis of graft copolymers consisting of a flexible polymyrcene backbone and poly(L-lactide) side chains using the "grafting from" approach. The graft copolymers are promising candidates for bio-based thermoplastic elastomers.

Fully saturated, aliphatic polymers containing adamantane moieties evenly distributed along the polymer backbone are of great interest due to their exceptional thermal stability, yet more synthetic strategies toward these polymers would be desirable. Herein, we report for the first time the synthesis of poly(1,3-adamantylene alkylene)s based on α,ω-dienes containing bulky 1,3-adamantylene defects precisely located on every 11th, 17th, 19th, and 21st chain carbon via acyclic diene metathesis polycondensation. All saturated polymers revealed excellent thermal stabilities (452–456 °C) that were significantly higher compared to those of structurally similar polyolefins with aliphatic or aromatic ring systems in the backbone of polyethylene (PE). Their crystallinity increases successively from shorter to longer CH2 chains between the adamantane defects. The adamantanes were located in the PE crystals distorting the PE unit cell by the incorporation of the adamantane defect at the kinks of a terrace arrangement. Precise positioning of structural defects within the polymeric backbone provides various opportunities to customize material properties by “defect engineering” in soft polymeric materials.

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Higher homologues of dibenzo[ c , e ][1,2]dithiin were synthesized from oligophenyls bearing multiple methylthio groups. Single‐crystal X‐ray analyses revealed their nonplanar structures and helical enantiomers of higher meta ‐congener 6 . Such dibenzo[1,2]dithiin homologues are demonstrated to be applicable to lithium‐ion batteries as cathode, displaying a high capacity of 118 mAh g −1 at a current density of 50 mA g −1 .

We report mechanistic insights of the bottom-up synthesis of nanodiamonds (NDs) from adamantane derivatives as molecular precursors. Thermal cracking of tetracosane below the decomposition temperature of adamantane, 1-adamantylamine or 2-azaadamantane revealed the initial steps of seeded diamond growth mechanism based on pyrolysis studies.