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Abstract The self‐assembly of amphiphilic bottlebrush block copolymers (BCPs), featuring backbones densely grafted with two types of side chains, is less well understood compared to linear BCPs. In particular, the solution self‐assembly of tapered bottlebrush BCPs—cone‐shaped BCPs with hydrophilic or hydrophobic tips—remains unexplored. This study investigates eight tapered and four cylindrical bottlebrush BCPs with varied ratios of hydrophobic polystyrene (PS) and hydrophilic poly(acrylic acid) (PAA) side chains, synthesized via sequential addition of macromonomers using ring‐opening metathesis polymerization (SAM‐ROMP). Self‐assembled nanostructures formed in water were analyzed using cryogenic transmission electron microscopy, small‐angle neutron scattering, and dynamic light scattering. Most BCPs generated multiple nanostructures with surface protrusions, including spherical micelles, cylindrical micelles, and vesicles, alongside transitional forms like ellipsoids and semi‐vesicles. Coarse‐grained molecular dynamics simulations supported the experimental findings, which revealed two distinct self‐assembly pathways. The first involved micelle fusion, producing elliptical and cylindrical aggregates, sometimes forming Y‐junctions. The second pathway featured micelle maturation into semivesicles, which developed into vesicles or large compound vesicles. This work provides the first experimental evidence of vesicle formation via semivesicles in bottlebrush BCPs and demonstrates the significant influence of cone directionality on self‐assembly behavior in these cone‐shaped polymeric amphiphiles. 

Abstract Polymeric donors of gasotransmitters, gaseous signaling molecules such as hydrogen sulfide, nitric oxide, and carbon monoxide, hold potential for localized and extended delivery of these reactive gases. Examples of gasotransmitter donors based on polysaccharides are limited despite the availability and generally low toxicity of this broad class of polymers. In this work, we sought to create a polysaccharide H₂S donor by covalently attachingN‐thiocarboxyanhydrides (NTAs) to amylopectin, the major component of starch. To accomplish this, we added an allyl group to an NTA, which can spontaneously hydrolyze to release carbonyl sulfide and ultimately H₂S via the ubiquitous enzyme carbonic anhydrase, and then coupled it to thiol‐functionalized amylopectin of three different molecular weights (MWs) through thiol‐ene “click” photochemistry. We also varied the degree of substitution (DS) of the NTA along the amylopectin backbone. H₂S release studies on the six samples, termed amyl‐NTAs, with variable MWs (three) and DS values (two), revealed that lower MW and higher DS led to faster release. Finally, dynamic light scattering experiments suggested that aggregation increased with MW, which may also have affected H₂S release rates. Collectively, these studies present a new synthetic method to produce polysaccharide H₂S donors for applications in the biomedical field. 

A block copolymer with the structure ethylcellulose-block-poly(benzy glutamate) was synthesizedviaring-opening polymerization and used as a compatibilizer to produce blends of ethylcellulose and poly(ethylene terephthalate). 

We describe the theory and application of SEC-MALS with minimal equations and a focus on synthetic polymer characterization. 

We report highk_p(macro)monomer structures for use in grafting-through ring-opening metathesis polymerization to make linear and bottlebrush polymers. 

We report a polymeric version of Piloty's acid where the release rate of HNO can be tuned by changing the block ratios of PEG- b -poly(Piloty's acid) in a block copolymer system. The poly(Piloty's acid) block was derived from poly(styrene sulfonate), and HNO release from the block copolymers varied by as much as an order of magnitude via increasing the length of the poly(Piloty's acid) block. We anticipate this study will guide the development of HNO-releasing polymers to measure the effects of sustained HNO delivery in biological systems.