The manufacturing of plastics traditionally involves melt processing at temperatures typically greater than 200 degrees C-to enable extrusion or moulding under pressure into desired forms-followed by solidification. This process consumes energy and can cause substantial degradation of polymers and additives (such as flame retardants and ultraviolet stabilizers), limiting plastics performance and recyclability. It was recently reported that the application of pressure could induce melt-like behaviour in the block copolymer polystyrene-block-poly(n-butyl methacrylate) (PS-b-PBMA), and this behaviour has now been demonstrated in a range of other block copolymer systems. These polymers have been termed baroplastics. However, in each case, the order-to-disorder transition, which gives rise to the accompanying change in rheology from soft solid to melt, was observed at temperatures far exceeding the glass transition temperatures (T(g)) of both components. Here we show that baroplastic systems containing nanophase domains of one high-T(g) and one low-T(g) component can exhibit melt-like flow under pressure at ambient temperature through an apparent semi-solid partial mixing mechanism that substantially preserves the high-T(g) phase. These systems were shredded and remoulded ten times with no evident property degradation. Baroplastics with low-temperature formability promise lower energy consumption in manufacture and processing, reduced use of additives, faster production and improved recyclability, and also provide potential alternatives to current thermoplastic elastomers, rubber-modified plastics, and semi-crystalline polymers.

Single-ion conducting block copolymer electrolytes were prepared in which counter ions were tethered to the polymer backbone to achieve a lithium transference number of unity. Through tailored anionic synthesis, the influence of counter ion placement on conductivity was investigated. Incorporating the anions outside the ion-conducting ͓poly͑ethylene oxide͒-based͔ block, such as in poly͑lauryl methacrylate͒-block-poly͑lithium methacrylate͒-block-poly͓(oxyethylene) 9 methacrylate͔, known as PLMA-b-PLiMA-b-POEM, and P͑LMA-r-LiMA͒-b-POEM, caused lithium ions to dissociate from the carboxylate counter ions upon microphase separation of the POEM and PLMA blocks, yielding conductivities of 10 Ϫ5 S/cm at 70°C. In contrast, incorporating anions into the conducting block, as in PLMA-b-P͑LiMA-r-OEM͒, rendered the majority of lithium ions immobile, resulting in conductivities one to two orders of magnitude lower over the range of temperatures studied for equivalent stoichiometries. Converting the carboxylate anion to one that effectively delocalized charge through complexation with the Lewis acid BF 3 raised the conductivity of the latter system to values comparable to those of the other electrolyte architectures. Ion dissociation could thus be equivalently achieved by using a low charge density counter ion (COOBF 3 Ϫ) or by spatially isolating the counter ion from the ion-conducting domains by microphase separation.

Rubbery−glassy block copolymer dispersions are an attractive solution for toughening rigid thermoplastics like polystyrene without affecting optical transparency. An interesting facet of the copolymers used is molecular disorder, artificially introduced during anionic synthesis through composition gradients along the copolymer chain and/or blending and partial coupling of different copolymers. In particular, this level of disorder is apparently a key to achieve the desired PS/copolymer blend morphologies and properties in short processing times. In this work, we investigate the role of these “synthesis imperfections” on self-assembly of styrene-rich asymmetric gradient triblock copolymers, denoted S1−G−S2, where Si are pure polystyrene blocks and G is a gradient copolymer of styrene and butadiene. Kinetic modeling of conversion data is used to predict gradient composition profiles for the anionic copolymerization conditions used. Self-assembly, dynamic viscoelastic behavior, and experimentally determined mesoscopic composition profiles across microdomains are discussed in light of the particular copolymer structure.