Bacterial infections and antibiotic resistance, particularly by Gram-negative pathogens, have become a global healthcare crisis. We report the design of a class of cationic antimicrobial polymers that cluster local facial amphiphilicity from repeating units to enhance interactions with bacterial membranes without requiring a globally conformational arrangement associated with highly unfavorable entropic loss. This concept of macromolecular architectures is demonstrated with a series of multicyclic natural product-based cationic polymers. We have shown that cholic acid derivatives with three charged head groups are more potent and selective than lithocholic and deoxycholic counterparts, particularly against Gram-negative bacteria. This is ascribed to the formation of true facial amphiphilicity with hydrophilic ion groups oriented on one face and hydrophobic multicyclic hydrocarbon structures on the opposite face. Such local facial amphiphilicity is clustered via a flexible macromolecular backbone in a concerted way when in contact with bacterial membranes.

Chemically inert, mechanically tough, cationic metallo-polyelectrolytes were conceptualized and designed as durable anion-exchange membranes (AEMs). Ring-opening metathesis polymerization (ROMP) of cobaltocenium-containing cyclooctene with triazole as the only linker group, followed by backbone hydrogenation, led to a new class of AEMs with a polyethylene-like framework and alkaline-stable cobaltocenium cation for ion transport. These AEMs exhibited excellent thermal, chemical and mechanical stability, as well as high ion conductivity.

Utilization of biomass for commodity polymers has gained tremendous interest. We report a method to prepare high molecular weight renewable homopolymers and block copolymers derived from natural rosin. Monomers with high renewable content (70 wt %) were prepared via a simple esterification reaction between dehydroabietic alcohol and 5exo-norbornenecarboxylic acid. Living and controlled polymerization of these monomers were achieved by ring-opening metathesis polymerization to obtain polymers with molecular weight up to ∼500 kg/mol. These homopolymers exhibit structure-dependent glass transition temperatures, excellent thermal stabilities, and thermoplastic properties. Chain entanglement molecular weight was determined via rheological assessments for such polymers with bulky side moieties. Using the living ROMP, dehydroabietic-based homopolymer was chainextended with a soybean oil-derived norbornene monomer to yield triblock copolymers, which showed behaviors of thermoplastic elastomers.

Dynamic crosslinking of commodity thermoplastics with multiple interfaces enables remarkably tough reversible adhesion.

The nature's intrigue plans to create structures from nano-micro to mesoscale has inspired researchers to design artificial object with novel and extra ordinary properties. Recently, the convergence of biomaterials and polymer advances from nano-to micro-scale with new experimental and computational tools has provided the opportunity to constitute increasingly complex fabrics for the textiles industry. In this regard, learning lessons from efficient natural processes to design smart fabrics, mimicking natural phenomena could revolutionize the textile industry for the design of interactive apparel. Here, we review 10 bio-inspired strategies to imply textile industry, to change the face of fashion and fabrics, based upon current advances in science to enrich diverse areas of textile industry. In each case, we present examples demonstrating nature's design and subsequent parallel advances in biomimetic materials and polymer sciences, combining interdisciplinary engineering principles to mimic nature inspired designs into fabrics. We predict as advances in science of biomimesis continue to unfold and uncover finer details, bioinspired emulations may increasingly give way to benefit in designing smart fabrics.

Graphene-based ion sensitive field effect transistors (GISFETs) with high sensitivity and selectivity for K + ion detection have been demonstrated utilizing valinomycin based ion selective membrane. The performance of the GISFET for K + ion detection was studied in various media over a concentration range of 1 µM-2 mM. The sensitivity of the sensor was found to be > 60 mV/decade, which is comparable to the best Si-based commercial ISFETs, with negligible interference found from Na + and Ca 2+ ions in high concentration. The sensor performance did not change significantly in Tris-HCl solution or with repeated testing over a period of two months highlighting its reliability and effectiveness for physiological monitoring. The performance of the sensor also remained unchanged when fabricated on biocompatible polyethylene terephthalate (PET) substrate, showing significant potential for developing flexible bio-implantable graphenebased ISFETs.

The fields of soft polymers and macromolecular sciences have enjoyed a unique combination of metals and organic frameworks in the name of metallopolymers or organometallic polymers. When metallopolymers carry charged groups, they form a class of metal-containing polyelectrolytes or metallo-polyelectrolytes. This review identifies the unique properties and functions of metallo-polyelectrolytes compared with conventional organo-polyelectrolytes, in the hope of shedding light on the formation of functional materials with intriguing applications and potential benefits. It concludes with a critical perspective on the challenges and hurdles for metallo-polyelectrolytes, especially experimental quantitative analysis and theoretical modeling of ionic binding.

Resin acids (or natural rosin) are a class of abundant, renewable natural biomass. Most low molecular weight resin acid-containing polymers are very brittle due to their low chain entanglement associated with the pendant, intrinsically bulky hydro­phenanthrene group. The use of block copolymer architectures can enhance chain entanglement and thus improve toughness. A–B–A type triblock and A–B–A–B–A type pentablock copolymers were synthesized by ring-opening metathesis polymerization (ROMP) with one-pot sequential monomer addition of a rosin-based monomer and norbornene. We investigated the effect of chain architecture and microphase separation on mechanical properties of both types of block copolymers. Pentablock copolymers exhibited higher strength and toughness as compared to both the triblock copolymers and the corresponding homopolymers. The greater toughness of pentablock copolymers is due to the presence of the rosin-based midblock chains that act as bridging chains between two polynorbornene domains. SAXS and AFM data were consistent with short-range phase separation of microdomains in all tri- and pentablock copolymers.