Synthesis of hyperbranched poly(1,2,3-triazole)s (hb-PTAs) has been a challenge: the AB 2 monomers were inclined to self-oligomerize, and their Cu(I)-catalyzed click polymerizations failed to yield soluble polymers. We tackled the challenge in this work and succeeded in generating hb-PTAs with regioregularity, processability, and functionality. We took an A 2 + B 3 approach and used diazides 2 and triyne 3 as monomers, which are free of self-oligomerization concerns. Thermal polymerizations of 2 and 3 produced regiorandom polymers (hb-r-P1) with high molecular weights in high yields. Metal-mediated regioselective polymerizations afforded soluble 1,4-and 1,5-linked polymers (hb-1,4-P1 and hb-1,5-P1), presenting the first examples of regioregular hb-PTAs with macroscopic processability. The reactions were affected by substrate and catalyst: electron-rich alkyne generally slowed down the cycloaddition reaction, while ruthenium catalysts (Cp*Ru(PPh 3 ) 2 Cl and [Cp*RuCl 2 ] n ) exhibited higher substrate tolerance than copper catalyst [Cu(PPh 3 ) 3 Br]. Regiostructures and regioregularities of the hb-PTAs were determined spectroscopically. Degrees of branching of hb-r-P1 were calculated to be ∼90%. Conformations of the hb-PTAs were affected by the steric effects between their aromatic units, which in turn affected their solubility, conjugation, luminescence, and aggregation. While the polymer solutions all emitted deep blue light, the films of hb-1,4-P1, hb-1,5-P1 and hb-r-P1 emitted blue, yellow, and white light, respectively, due to the difference in the aggregation of their chromophoric units in the solid state. Fluorescent photoresist patterns with various emission colors were readily generated from photo-cross-linking of the polymers through a nitrene-mediated photolysis mechanism.

The well-defined block copolymer of poly(ethylene oxide)-b-poly(N-isopropylacrylamide) (PEOb-PNIPAm) was synthesized by the reversible addition fragmentation transfer (RAFT) polymerization, and its thermo-induced aggregation process in dilute aqueous solution was studied by laser light scattering. At temperatures below the cloud point of PNIPAm, the PEO-b-PNIPAm chains were associated together to form large and loose structures, which were in a fast equilibrium with the single chains. The association was weakened with increasing concentration, which was against the common ideas about aggregation. Because of such "abnormal" behavior, PEO-b-PNIPAm underwent three stages of transformation during the heating process at 0.1 mg/mL: the disassociation of loose associates at temperatures below 28 °C, the micellization above 42 °C, and the aggregation in between. At each stage, the size and M w,app exhibited distinct features. On the basis of these observations, possible mechanisms of the association and aggregation were also proposed.