High sulfur content copolymers were prepared via inverse vulcanization of sulfur with 1,4-diphenylbutadiyne (DiPhDY) for use as the active cathode material in lithium-sulfur batteries. These sulfur-rich polymers exhibited excellent capacity retention (800 mA h g À1 at 300 cycles) and extended battery lifetimes of over 850 cycles at C/5 rate. Fig. 3 (a) Cycling performance at C/5 of Li-S battery fabricated with poly(S-co-DiPhDY) prepared with a 10 wt% DiPhDY, 90 wt% sulfur feed ratio. (b) Plot of potential versus charge/discharge capacity for the Li-S cell shown in (a) at 100 cycle intervals. (c) Charge/discharge rate performance of Li-S battery with poly(S-co-DiPhDY) (10 wt% DiPhDY) at various current densities (1 C ¼ 1672 mA h). All capacities are specific capacity based on sulfur loading.This journal is

A methodology providing access to dumbbell-tipped, metal-semiconductor and metal oxide-semiconductor heterostructured nanorods has been developed. The synthesis and characterization of CdSe@CdS nanorods incorporating ferromagnetic cobalt nanoinclusions at both nanorod termini (i.e., dumbbell morphology) are presented. The key step in the synthesis of these heterostructured nanorods was the decoration of CdSe@CdS nanorods with platinum nanoparticle tips, which promoted the deposition of metallic CoNPs onto Pt-tipped CdSe@CdS nanorods. Cobalt nanoparticle tips were then selectively oxidized to afford CdSe@CdS nanorods with cobalt oxide domains at both termini. In the case of longer cobalt-tipped nanorods, heterostructured nanorods were observed to self-organize into complex dipolar assemblies, which formed as a consequence of magnetic associations of terminal CoNP tips. Colloidal polymerization of these cobalt-tipped nanorods afforded fused nanorod assemblies from the oxidation of cobalt nanoparticle tips at the ends of nanorods via the nanoscale Kirkendall effect. Wurtzite CdS nanorods survived both the deposition of metallic CoNP tips and conversion into cobalt oxide phases, as confirmed by both XRD and HRTEM analysis. A series of CdSe@CdS nanorods of four different lengths ranging from 40 to 174 nm and comparable diameters (6-7 nm) were prepared and modified with both cobalt and cobalt oxide tips. The total synthesis of these heterostructured nanorods required five steps from commercially available reagents. Key synthetic considerations are discussed, with particular emphasis on reporting isolated yields of all intermediates and products from scale up of intermediate precursors.

We report on a new class of thermoresponsive biodegradable polyesters (TR-PE) inspired by polyacrylamides and elastin-like proteins (ELPs). The polyesters display reversible phase transition with tunable cloud point temperatures (T cp ) in aqueous solution as evidenced by UV−vis spectroscopy, 1 H NMR, and DLS measurements. These polyesters form coacervate droplets above their lower critical solution temperature (LCST). The T cp of the polyesters is influenced by the solutes such as urea, SDS, and NaCl. The T cp of the copolymers shows a linear correlation with the composition of the polyesters indicating the ability to tune the phase change temperature. We also show that such thermoresponsive coacervates are capable of encapsulating small molecules such as Nile Red. Furthermore, the polyesters are hydrolytically degradable.

The nanophase separation in diblock and triblock copolymers consisting of immiscible poly(n butyl acrylate) (block A) and gradient copolymers of methyl methacrylate (MMA) and n butyl acrylate (n BA) (block M/A) were investigated by means of their heat capacity, C p , as a function of the composition of the blocks M/A and temperature. In all copolymers studied, both blocks are represented by their C p and glass transition temperature, T g , as well as the broadening of the transition temperature range. The low temperature transition of the blocks A is always close to that of the pure poly(n butyl acrylate) and is independent of the analyzed compositions of the block copolymer, but broadened asymmetrically relative to the homopolymer due to the small phase size. The higher transition is related to the glass transition of the copolymer block of composition M/A. Besides the asymmetric broadening of the transition due to the phase separation, it decreases in T g and broadens, in addition, symmetrically with increasing acrylate content. The concentration gradient is not able to introduce a further phase separation with a third glass transition inside the M/A block.