A family of coil−rod−coil ABA triblock copolymers containing poly(3-hexylthiophene) (P3HT) and poly(hexadecyloxyallene) (PHA) were facilely synthesized in one-pot via three sequential living polymerizations of hexadecyloxyallene, 2-bromo-3-hexyl-5-chloromagnesiothiophene, and hexadecyloxyallene using the π-allylnickel complex as a single catalyst. Although the different monomers were polymerized under distinct polymerization mechanisms, the one-pot block copolymerization were revealed to proceed in a living/controlled chain-growth manner, affording welldefined PHA-b-P3HT-b-PHA triblock copolymers in high yields with controlled molecular weights and tunable compositions. The isolated triblock copolymers were found to self-assemble into well-defined supramolecular helical polymers with equivalent of right-and left-handedness. The helicity of the assemblies can be facilely tuned through the induction of chiral cholesteryl pendants introduced on the polyallene segments. Moreover, by using this synthetic method, amphiphilic P3HT triblock copolymers containing hydrophobic P3HT and hydrophilic poly(triethylene glycol allene) (PTA) were readily prepared. Such water-soluble PTA-b-P3HT-b-PTA triblock copolymer exhibited multiresponsiveness including solvent, pH, and temperature.

Conjugated block copolymers with tunable properties have attract considerable research interests in recent years. Herein, we report a series of novel block copolymers containing conjugated poly(3-hexylthiophene) (P3HT) and poly(triethyl glycol allene) (PTA) segments which were synthesized in one pot using nickel complex as a single catalyst via distinct polymerization mechanisms. Interestingly, the P3HT-b-PTA diblock copolymers exhibit excellent thermoresponsive properties in water, and the lower critical solution temperature (LCST) is dependent on polymer concentration and the block ratio. Moreover, the diblock copolymers showed pH-responsive properties in CHCl 3 with the emission color shuttled between orange and deep green upon the alternate additions of trifluoroacetic acid and triethylamine. Both P3HT-b-PTA and P3HT-b-PTA-b-P3HT block copolymers exhibit solvatochromism properties. The emission of the block copolymers can be facilely tuned through variation on solvents with the emission color spanned widely from red to blue. Very interestingly, white-light emission can be readily achieved from the P3HT-b-PTA-b-P3HT triblock copolymer in the mixture of THF and methanol with 1/3 volume ratio.

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Eucommia ulmoides gum (EUG) was applied in blend rubber with a heavily limited amount because of its duality of rubber and plastic, and an efficient way of triazolinedione (TAD)-based Alder-ene reaction was used to improve the elastic properties of EUG. Binary modification of EUG with two TADs containing hexyl and polyhedral oligomeric silsesquioxane (POSS) groups were conducted to generate the modified EUG elastomers with tunable mechanical properties and good compatibility by varying TAD contents. When the low hexyl (1%) and POSS (0.2%) TADs incorporated, the modified EUGs displayed high tensile strength of 36.57 MPa with the elongation at break of 876%, and thus high toughness of 152.14 MJ m −3 . If high contents of hexyl (20%) and POSS (0.2%) TADs employed, the modified EUGs exhibited excellent elongation at break of 1165% and recovery rate of 60%, and especially its loss factor reached up to 0.83-0.65 at 20-70 C. Therefore, the modified EUGs containing the polar urazole and POSS groups should be a novel elastomer with good compatibility, wear resistance, and damping properties.

Block copolymers with push–pull azobenzene pendants and core–shell nanostructures exhibited high and regulated dielectric constants by photoisomerization of azobenzene groups, low dielectric loss, and high energy density.