Cylinders-in-Undulating-Lamellae Morphology from ABC Bottlebrush Block Terpolymers.

Block polymer self-assembly affords a versatile bottom-up strategy to develop materials with the desired properties dictated by specific symmetries and dimensions. Owing to distinct properties compared with linear counterparts, bottlebrush block polymers with side chains densely grafted on a backbone have attracted extensive attention. However, the morphologies found in bottlebrush block polymers so far are limited, and only lamellar and cylindrical ordered phases have been reported in diblock bottlebrushes.

Crystallization inhibition in molecular liquids by polymers above the overlap concentration (c*): Delay of the first nucleation event.

Low concentration polymer additives can significantly alter crystal growth kinetics of molecular liquids and glasses. However, the effect of polymer concentration on nucleation kinetics remains poorly understood. Based on an experimentally determined first nucleation time (time to form the first critical nucleus, t), we show that the polymer overlap concentration, c*, where polymer coils in the molecular liquid start to overlap with each other, is a critical polymer concentration for efficient inhibition of crystallization of a molecular liquid.

Threading-the-Needle: Compatibilization of HDPE/PP blends with butadiene-derived polyolefin block copolymers.

Management of the plastic industry is a momentous challenge, one that pits enormous societal benefits against an accumulating reservoir of nearly indestructible waste. A promising strategy for recycling polyethylene (PE) and isotactic polypropylene (PP), constituting roughly half the plastic produced annually worldwide, is melt blending for reformulation into useful products. Unfortunately, such blends are generally brittle and useless due to phase separation and mechanically weak domain interfaces.

Accelerating bone regeneration in cranial defects using an injectable organic-inorganic composite hydrogel.

Bone tissue engineering, as an important and attractive multidisciplinary field, affords a feasible strategy for large bone defects which are difficult to heal without clinical intervention. However, the complicated requirements of bone regeneration result in the imperfect performance of many current materials. Inspired by the composite nature of bone tissues, we proposed an organic-inorganic composite strategy.

Dynamically Resettable Electrode-Electrolyte Interface through Supramolecular Sol-Gel Transition Electrolyte for Flexible Zinc Batteries.

Flexible batteries based on gel electrolytes with high safety are promising power solutions for wearable electronics but suffer from vulnerable electrode-electrolyte interfaces especially upon complex deformations, leading to irreversible capacity loss or even battery collapse. Here, a supramolecular sol-gel transition electrolyte (SGTE) that can dynamically accommodate deformations and repair electrode-electrolyte interfaces through its controllable rewetting at low temperatures is designed. Mediated by the micellization of polypropylene oxide blocks in Pluronic and host-guest interactions between α-cyclodextrin (α-CD) and polyethylene oxide blocks, the high ionic conductivity and compatibility with various salts of SGTE afford resettable electrode-electrolyte interfaces and thus constructions of a series of highly durable, flexible aqueous zinc batteries.

Core-Shell Gyroid in ABC Bottlebrush Block Terpolymers.

Block polymer self-assembly provides a versatile platform for creating useful materials endowed with three-dimensional periodic network morphologies that support orthogonal physical properties such as high ionic conductivity and a high elastic modulus. However, coil configurations limit conventional linear block polymers to finite ordered network dimensions, which are further restricted by slow self-assembly kinetics at high molecular weights. A bottlebrush architecture can circumvent both shortcomings owing to extended backbone configurations due to side chain crowding and molecular dynamics substantially free of chain entanglements.

Injectable Thermogel Generated by the "Block Blend" Strategy as a Biomaterial for Endoscopic Submucosal Dissection.

Endoscopic submucosal dissection is an established method for the removal of early cancers and large lesions from the gastrointestinal tract but is faced with the risk of perforation. To decrease this risk, a submucosal fluid cushion (SFC) is needed clinically by submucosal injection of saline and so on to lift and separate the lesion from the muscular layer. Some materials have been tried as the SFC so far with disadvantages.

Cell-Free Bilayered Porous Scaffolds for Osteochondral Regeneration Fabricated by Continuous 3D-Printing Using Nascent Physical Hydrogel as Ink.

Cartilage is difficult to self-repair and it is more challenging to repair an osteochondral defects concerning both cartilage and subchondral bone. Herein, it is hypothesized that a bilayered porous scaffold composed of a biomimetic gelatin hydrogel may, despite no external seeding cells, induce osteochondral regeneration in vivo after being implanted into mammal joints. This idea is confirmed based on the successful continuous 3D-printing of the bilayered scaffolds combined with the sol-gel transition of the aqueous solution of a gelatin derivative (physical gelation) and photocrosslinking of the gelatin methacryloyl (gelMA) macromonomers (chemical gelation).

Cell migration regulated by RGD nanospacing and enhanced under moderate cell adhesion on biomaterials.

While nanoscale modification of a biomaterial surface is known to influence various cell behaviors, it is unclear whether there is an optimal nanospacing of a bioactive ligand with respect to cell migration. Herein, we investigated the effects of nanospacing of arginine-glycine-aspartate (RGD) peptide on cell migration and its relation to cell adhesion. To this end, we prepared RGD nanopatterns with varied nanospacings (31-125 nm) against the nonfouling background of poly(ethylene glycol), and employed human umbilical vein endothelial cells (HUVECs) to examine cell behaviors on the nanopatterned surfaces.

Structural mechanics of 3D-printed poly(lactic acid) scaffolds with tetragonal, hexagonal and wheel-like designs.

While various porous scaffolds have been developed, the focused study about which structure leads to better mechanics is rare. In this study, we designed porous scaffolds with tetragonal, hexagonal and wheel-like structures under a given porosity, and fabricated corresponding poly(lactic acid) (PLA) scaffolds with three-dimensional printing. High-resolution micro-computed tomography was carried out to calculate their experimental porosity and confirm their high interconnectivity.

Strategy of Metal-Polymer Composite Stent To Accelerate Biodegradation of Iron-Based Biomaterials.

The new principle and technique to tune biodegradation rates of biomaterials is one of the keys to the development of regenerative medicine and next-generation biomaterials. Biodegradable stents are new-generation medical devices applied in percutaneous coronary intervention, etc. Recently, both corrodible metals and degradable polymers have drawn much attention in biodegradable stents or scaffolds.

Achieving High Drug Loading and Sustained Release of Hydrophobic Drugs in Hydrogels through In Situ Crystallization.

Inadequate drug loading of hydrophobic drugs is a classic problem when hydrogels are utilized as sustained-release carriers of drugs. Herein, a strategy to load plenty of hydrophobic drugs is presented. The antitumor drug 10-hydroxycamptothecin in the thermogel of poly(d,l-lactic acid-co-glycolic acid)-b-poly(ethylene glycol)-b-poly(d,l-lactic acid-co-glycolic acid) is employed.