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1.
Macromol Rapid Commun ; 42(6): e2000578, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33274810

RESUMEN

The synthesis of hyperbranched aminobisphosphonic acid polymers via reversible addition-fragmentation chain transfer (RAFT) self-condensing vinyl polymerization is reported. A novel acrylamide-functional chain transfer monomer is synthesized and characterized by 1 H and 13 C NMR spectroscopy, elemental analysis, and mass spectrometry. The monomer is subsequently copolymerized with an acrylamide monomer bearing a pendent amine group to create hyperbranched amine-functional polymers with degrees of branching dictated by changing the reaction stoichiometry. The aminobisphosphonate functional group is introduced via a 3-component Kabachnik-Fields reaction. An alternate functionalization of the amine polymers to create acid-degradable imine hydrogels is also employed. This work demonstrates the application of multicomponent reactions to RAFT-derived hyperbranched polymers and provides a new route to previously inaccessible polymers.


Asunto(s)
Difosfonatos , Polímeros , Sustancias Macromoleculares , Polimerizacion , Cloruro de Polivinilo
2.
ACS Appl Mater Interfaces ; 14(48): 54245-54255, 2022 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-36440705

RESUMEN

Recent developments of highly expandable foaming pre-polymer resins for lithographic additive manufacturing have allowed for the creation of structures larger than a printer's build envelope. To fully utilize the capabilities of this technology, the mechanical properties of these foams must be improved. This manuscript presents one method for strengthening these lightweight polymeric structures via aerosol spray application of a high-strength, low-viscosity photocurable coating. This method is free from the reliance on often complex, large, or bulky on-site equipment ordinarily required by conventional high-strength spray coating. The newly formulated photocurable resin can be applied using an ordinary cordless paint sprayer and cured using sunlight in less than a minute, enabling the rapid production of large, load-bearing structures from a small volume of feedstock and low-cost portable equipment. A comprehensive screening process for resin formulations, detailed mechanical compression and tensile analysis of coated polymer structures, and an applied technical demonstration of the technology are described. The photocurable coating described herein greatly strengthens porous polymeric structures using a method that can be easily implemented.

3.
Macromol Biosci ; 22(12): e2200292, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36122179

RESUMEN

Blood loss causes an estimated 1.9 million deaths per year globally, making new methods to stop bleeding and promote clot formation immediately following injury paramount. The fabrication of functional hemostatic materials has the potential to save countless lives by limiting bleeding and promoting clot formation following an injury. This work describes the melt manufacturing of poly(ε-caprolactone) nanofibers and their chemical functionalization to produce highly scalable materials with enhanced blood clotting properties. The nanofibers are manufactured using a high throughput melt coextrusion method. Once isolated, the nanofibers are functionalized with polymers that promote blood clotting through surface-initiated atom transfer radical polymerization. The functional nanofibers described herein speed up the coagulation cascade and produce more robust blood clots, allowing for the potential use of these functional nonwoven mats as advanced bandages.


Asunto(s)
Hemostáticos , Nanofibras , Trombosis , Humanos , Nanofibras/química , Coagulación Sanguínea , Hemostáticos/química , Vendajes , Hemorragia
4.
ACS Appl Mater Interfaces ; 13(50): 59618-59632, 2021 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-34890195

RESUMEN

Proteinaceous nanoparticles can be used to deliver large payloads of active ingredients, which is advantageous in medicine and agriculture. However, the conjugation of hydrophobic ligands to hydrophilic nanocarriers such as plant viral nanoparticles (plant VNPs) can result in aggregation by reducing overall solubility. Given the benefits of hydrophilic nanocarrier platforms for targeted delivery and multivalent ligand display, coupled with the versatility of hydrophobic drugs, contrast agents, and peptides, this is an issue that must be addressed to realize their full potential. Here, we report two preincubation strategies that use a Pluronic F127 polymer scaffold to prevent the aggregation of conjugated plant VNPs: a plant VNP-polymer precoat (COAT) and an active ingredient formulation combined with a plant VNP-polymer precoat (FORMCOAT). The broad applications of these modified conjugation strategies were highlighted by testing their compatibility with three types of bioconjugation chemistry: N-hydroxysuccinimide ester-amine coupling, maleimide-thiol coupling, and copper(I)-catalyzed azide-alkyne cycloaddition (click chemistry). The COAT and FORMCOAT strategies promoted efficient bioconjugation and prevented the aggregation that accompanies conventional bioconjugation methods, thus improving the stability, homogeneity, and translational potential of plant VNP conjugates in medicine and agriculture.


Asunto(s)
Materiales Biocompatibles/química , Nanopartículas/química , Poloxámero/química , Interacciones Hidrofóbicas e Hidrofílicas , Ligandos , Ensayo de Materiales , Estructura Molecular , Tamaño de la Partícula
5.
ACS Appl Mater Interfaces ; 12(16): 19033-19043, 2020 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-32267677

RESUMEN

In modern manufacturing, it is a widely accepted limitation that the parts patterned by an additive or subtractive manufacturing process (i.e., a lathe, mill, or 3D printer) must be smaller than the machine itself that produced them. Once such parts are manufactured, they can be postprocessed, fastened together, welded, or adhesively bonded to form larger structures. We have developed a foaming prepolymer resin for lithographic additive manufacturing, which can be expanded after printing to produce parts up to 40× larger than their original volume. This allows for the fabrication of structures significantly larger than the build volume of the 3D printer that produced them. Complex geometries comprised of porous foams have implications in technologically demanding fields such as architecture, aerospace, energy, and biomedicine. This manuscript presents a comprehensive screening process for resin formulations, detailed analysis of printing parameters, and observed mechanical properties of the 3D-printed foams.

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