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1.
Macromol Rapid Commun ; 45(8): e2300675, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38163327

RESUMO

Despite their industrial ubiquity, polyolefin-polyacrylate block copolymers are challenging to synthesize due to the distinct polymerization pathways necessary for respective blocks. This study utilizes MILRad, metal-organic insertion light-initiated radical polymerization, to synthesize polyolefin-b-poly(methyl acrylate) copolymer by combining palladium-catalyzed insertion-coordination polymerization and atom transfer radical polymerization (ATRP). Brookhart-type Pd complexes used for the living polymerization of olefins are homolytically cleaved by blue-light irradiation, generating polyolefin-based macroradicals, which are trapped with functional nitroxide derivatives forming ATRP macroinitiators. ATRP in the presence of Cu(0), that is, supplemental activators and reducing agents , is used to polymerize methyl acrylate. An increase in the functionalization efficiency of up to 71% is demonstrated in this study by modifying the light source and optimizing the radical trapping condition. Regardless of the radical trapping efficiency, essentially quantitative chain extension of polyolefin-Br macroinitiator with acrylates is consistently demonstrated, indicating successful second block formation.


Assuntos
Resinas Acrílicas , Polienos , Polimerização , Polienos/química , Polienos/síntese química , Resinas Acrílicas/química , Resinas Acrílicas/síntese química , Catálise , Polímeros/química , Polímeros/síntese química , Paládio/química , Estrutura Molecular , Acrilatos/química , Luz
2.
Int J Biol Macromol ; 253(Pt 8): 127513, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37865371

RESUMO

The inherent highly hydrophilic feature of cellulose-based paper hinders its application in many fields. Herein, a cellulose-based hydrophobic paper was fabricated based on surface chemical modification. Firstly, the hydrophobic acrylate components were bonded to the cellulose acetoacetate (CAA) fibers to obtain CAA graft acrylate (CAA-X) fibers through Michael addition reaction. Subsequently, CAA-X fibers were processed into paper via wet papermaking technology. The resulting paper exhibited good hydrophobic performance (water contact angle was up to 135°) with an air permeability of 24.8 µm/Pa·s. The hydrophobicity of paper was very stable and remained even after treating with different solvents. Moreover, the hydrophobic properties of this paper could be adjusted by changing the type of acrylate component. It should be noted that the surface modification strategy has no obvious effects on the whiteness (79.8%), writing, and printing properties of the cellulose fibers. Thus, it is a simple, benign, and efficient strategy for the construction of cellulose-based hydrophobic paper, which has great potential to be used in paper tableware, oil-water separation, watercolor protection, and food packaging fields.


Assuntos
Celulose , Água , Celulose/química , Interações Hidrofóbicas e Hidrofílicas , Água/química , Solventes , Acrilatos/química
3.
Macromol Rapid Commun ; 44(19): e2300258, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37496370

RESUMO

A novel open-to-air photo RAFT polymerization of a series of acrylate and methacrylate monomers mediated by matching chain transfer agent irradiated by far-red light in DMSO is reported. Hydroxyl radical (•OH) generated from methylene blue (MB) sensitized decomposition of H2 O2 via photo-Fenton like-reaction is used for polymerization initiation. The "living/control" characteristic is evidenced by kinetic study, in which a pseudo first order curve and linearly increases of molecular weight with the increase of monomer conversion are observed. The living end-group fidelity is characterized by MALDI-TOF-MS and 1 H NMR results, and confirmed by successful chain extension. The temporary controllability is proved by light on/off switch experiment.


Assuntos
Dimetil Sulfóxido , Azul de Metileno , Polimerização , Polímeros/química , Acrilatos/química
4.
ACS Biomater Sci Eng ; 9(7): 4223-4240, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37379254

RESUMO

Polymeric microparticles are promising biomaterial platforms for targeting macrophages in the treatment of disease. This study investigates microparticles formed by a thiol-Michael addition step-growth polymerization reaction with tunable physiochemical properties and their uptake by macrophages. The hexafunctional thiol monomer dipentaerythritol hexa-3-mercaptopropionate (DPHMP) and tetrafunctional acrylate monomer di(trimethylolpropane) tetraacrylate (DTPTA) were reacted in a stepwise dispersion polymerization, achieving tunable monodisperse particles over a size range (1-10 µm) relevant for targeting macrophages. An off-stoichiometry thiol-acrylate reaction afforded facile secondary chemical functionalization to create particles with different chemical moieties. Uptake of the microparticles by RAW 264.7 macrophages was highly dependent on treatment time, particle size, and particle chemistry with amide, carboxyl, and thiol terminal chemistries. The amide-terminated particles were non-inflammatory, while the carboxyl- and thiol-terminated particles induced pro-inflammatory cytokine production in conjunction with particle phagocytosis. Finally, a lung-specific application was explored through time-dependent uptake of amide-terminated particles by human alveolar macrophages in vitro and mouse lungs in vivo without inducing inflammation. The findings demonstrate a promising microparticulate delivery vehicle that is cyto-compatible, is non-inflammatory, and exhibits high rates of uptake by macrophages.


Assuntos
Macrófagos , Compostos de Sulfidrila , Animais , Camundongos , Humanos , Compostos de Sulfidrila/química , Acrilatos/química , Amidas
5.
ACS Biomater Sci Eng ; 9(7): 4269-4276, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37354100

RESUMO

Elucidating the fouling phenomena of polymer surfaces will facilitate the molecular design of high-performance biomedical devices. Here, we investigated the remarkable antifouling properties of two acrylate materials, poly(2-methoxyethyl acrylate) (PMEA) and poly(3-methoxypropionic acid vinyl ester) (PMePVE), which have a terminal methoxy group on the side chain, via molecular dynamics simulations of binary mixtures of acrylate/methacrylate trimers with n-pentane or 2,2-dimethylpropane (neopentane), that serve as the nonpolar organic probe (organic foulants). The second virial coefficient (B2) was determined to assess the aggregation/dispersion properties in the binary mixtures. The order of the B2 values for the trimer/pentane mixtures indicated that the terminal methoxy group of the side chain plays an important role in enhancing the fouling resistance to nonpolar organic foulants. Here, we hypothesized that the antifouling properties of PMEA/PMePVE surfaces originate from the resistance. To evaluate the molecular-level accessibility of organic foulants to acrylate/methacrylate materials, we examined the radial distribution functions (RDFs) of the terminal methyl groups of neopentane around the main chains of the acrylate/methacrylate trimers. As a result, the third distinct RDF peaks are observed only for the methacrylate trimers. The peaks are attributed to the hydrophobic interactions between the methyl group of neopentane and that of the main chain of the trimer. Accordingly, the methyl group of the main chain of methacrylate materials, such as poly(2-hydroxyethyl methacrylate) and poly(2-methoxyethyl methacrylate), unfavorably induces fouling with organic foulants. In this study, we clarify that preventing hydrophobic interactions between an organic foulant and polymeric material is essential for enhancing the antifouling property. Our approach has great potential for evaluating the molecular-level affinities of organic foulant with polymer surfaces for the molecular design of excellent antifouling polymeric materials.


Assuntos
Incrustação Biológica , Simulação de Dinâmica Molecular , Estrutura Molecular , Materiais Biocompatíveis , Incrustação Biológica/prevenção & controle , Polímeros/farmacologia , Polímeros/química , Acrilatos/farmacologia , Acrilatos/química , Metacrilatos/farmacologia
6.
Macromol Rapid Commun ; 44(9): e2300066, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36943391

RESUMO

Poly(methyl methacrylate) (PMMA) is a well-known and widely used commodity plastic. High production amount of PMMA causes excessive waste creation that highlights the necessity of recycling. Conventional recycling methods require elevated temperatures to induce degradation or depolymerization. In this work, visible light induced photodegradation system by using dimanganese decacarbonyl (Mn2 (CO)10 ) with high halogen affinity is reported. Halide functional photodegradable polymers are prepared by copolymerization of methyl methacrylate and methyl α-chloroacrylate by conventional reversible addition-fragmentation chain-transfer polymerization. Synthesized copolymers are efficiently degraded to low molecular weight oligomers under visible light irradiation in the presence of Mn2 (CO)10 . Characteristics of precursors, degraded polymers, and kinetics of depolymerization are investigated by gel permeation chromatography (GPC), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), Fourrier transform infrared (FTIR), and proton nuclear magnetic resonance (1 H-NMR) spectroscopies. The reported approach is expected to trigger further development of more environmentally friendly recycling techniques in the near future as we  are moving toward a greener and more sustainable world.


Assuntos
Polímeros , Polimetil Metacrilato , Polimetil Metacrilato/química , Temperatura , Polímeros/química , Acrilatos/química , Metacrilatos/química
7.
J Chromatogr A ; 1695: 463933, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-36966604

RESUMO

The facile preparation of a monolithic capillary column with surface bound polar ligands for use in hydrophilic interaction capillary electrochromatography is described. It involved the conversion of poly(carboxyethyl acrylate[CEA]-co-ethylene glycol dimethacrylate[EDMA]) precursor monolith (the so-called carboxy monolith) into a Tris bonded monolith by a post-polymerization functionalization process in the presence of a water soluble carbodiimide, namely N-(3-dimethylaminopropyl)-N´-ethylcarbodiimidehydrochloride. The carbodiimide assisted conversion, allowed the covalent attachment of the carboxyl group of the precursor monolith to the amino group of the Tris ligand via a stable amide linkage. This resulted in the formation of Tris poly(CEA-co-EDMA) monolith, which exhibited the typical retention behavior of hydrophilic interaction stationary phase when analyzing polar and slightly polar neutral or charged compounds. In fact, neutral polar species such as dimethylformamide, formamide and thiourea were retained in the order of increased polarity with acetonitrile rich mobile phase. Also, neutral p-nitrophenyl maltooligosaccharides (PNP-maltooligosaccharides) served as a polar homologous series for gauging the hydrophilicity of the Tris poly(CEA-co-EDMA) monolith, thus forming a versatile testing homologous series for other hydrophilic columns. Other polar anionic species (e.g., hydroxy benzoic acids and nucleotides) and weakly polar anionic compounds (e.g., dansyl amino acids and phenoxy acid herbicides) as well as polar weak bases namely nucleobases and nucleosides were used to probe the hydrophilic characters of the Tris poly(CEA-co-EDMA) monolith. The various polar and weakly polar compounds just mentioned revealed the wide potentiality of the hydrophilic interaction column under investigation.


Assuntos
Eletrocromatografia Capilar , Eletrocromatografia Capilar/métodos , Ligantes , Metacrilatos/química , Acrilatos/química , Interações Hidrofóbicas e Hidrofílicas
8.
Int J Mol Sci ; 24(4)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36835361

RESUMO

Here we aimed to establish a simple detection method for detecting circulating tumor cells (CTCs) in the blood sample of colorectal cancer (CRC) patients using poly(2-methoxyethyl acrylate) (PMEA)-coated plates. Adhesion test and spike test using CRC cell lines assured efficacy of PMEA coating. A total of 41 patients with pathological stage II-IV CRC were enrolled between January 2018 and September 2022. Blood samples were concentrated by centrifugation by the OncoQuick tube, and then incubated overnight on PMEA-coated chamber slides. The next day, cell culture and immunocytochemistry with anti-EpCAM antibody were performed. Adhesion tests revealed good attachment of CRCs to PMEA-coated plates. Spike tests indicated that ~75% of CRCs from a 10-mL blood sample were recovered on the slides. By cytological examination, CTCs were identified in 18/41 CRC cases (43.9%). In cell cultures, spheroid-like structures or tumor-cell clusters were found in 18/33 tested cases (54.5%). Overall, CTCs and/or growing circulating tumor cells were found in 23/41 CRC cases (56.0%). History of chemotherapy or radiation was significantly negatively correlated with CTC detection (p = 0.02). In summary, we successfully captured CTCs from CRC patients using the unique biomaterial PMEA. Cultured tumor cells will provide important and timely information regarding the molecular basis of CTCs.


Assuntos
Neoplasias Colorretais , Células Neoplásicas Circulantes , Humanos , Acrilatos/química , Neoplasias Colorretais/patologia , Células Neoplásicas Circulantes/patologia , Polímeros/química , Células Tumorais Cultivadas , Técnicas de Cultura de Células
9.
Macromol Rapid Commun ; 44(1): e2200404, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35750641

RESUMO

The current work presents the study of a semicrystalline, shape memory polymer synthesized by simultaneous free radical polymerization and crosslinking in a blend of polybutadiene (PB) and octadecyl acrylate. Blending elastomers and phase change materials provide a modular method for new smart materials, such as shape memory polymers. In this system, grafted, side-chain crystalline poly(octadecyl acrylate) (PODA) fixes a programmed shape in the shape memory cycle, while crosslinked polybutadiene drives shape recovery. This work focuses on improving material parameters important for shape memory (crystallinity, gel fraction, melting temperature) by tuning the processing and formulation parameters (amount of crosslinker and PB weight fraction). The result is a shape memory PB-PODA copolymer that can be fabricated by melt processing and programmed without cooling below ambient temperature. It is found that good shape memory (i.e., high shape fixity and recovery) is obtained at a low PB weight fraction where a percolating PODA crystal network is formed at room temperature. The optimized sample shows excellent shape memory properties (fixity > 99%, recovery = 96%). It is shown that it is possible to mold this material into complex 3D shapes or topography with potential use in anticounterfeiting and antitampering applications.


Assuntos
Elastômeros , Polímeros , Polímeros/química , Polimerização , Acrilatos/química
10.
J Chromatogr A ; 1688: 463713, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36535112

RESUMO

In this research report, the previously developed poly(carboxyethyl acrylate-co-ethylene glycol dimethacrylate) precursor monolith (referred to as carboxy monolith) is further exploited in the preparation of a chiral stationary phase for enantiomeric separations. The carboxy monolith precursor was subjected to post polymerization functionalization (PPF) with the chiral selector (S)-(-)-1-(2-naphthyl) ethylamine (NAS) at room temperature in the presence of N, N´-dicyclohexylcarbodiimide (DCC) in chloroform. The DCC, which is an organic soluble carbodiimide, permits the linkage for the amine functionality of the chiral ligand NAS to the carboxy group of the monolithic surface forming a stable amide linkage. The NAS column thus obtained allowed not only enantiomeric separations in the RP mode via its chiral site but also the separation of nonpolar species via its achiral functionality offering both hydrophobic and π-π interactions for aromatic compounds such toluene derivatives and polyaromatic hydrocarbons. The dual interaction sites (e.g., chiral, and achiral) of the NAS present a convenient column for the separations of slightly polar and nonpolar chiral and achiral solutes in the RP mode.


Assuntos
Eletrocromatografia Capilar , Eletrocromatografia Capilar/métodos , Ligantes , Acrilatos/química , Etilaminas
11.
Int J Pharm ; 629: 122362, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36379396

RESUMO

This research aimed to create new hydrophilic drug-in-adhesive patches for transdermal drug delivery. Poly(hydroxyethyl acrylate-co-itaconic acid)-catechol (PHI-cat) and hyaluronic acid (HA) were used as main components in the pressure-sensitive adhesive. Citric acid and aluminium hydroxide were exploited as crosslinking agents and ketoprofen was employed as a model delivering compound. The adhesive performance, physicochemical properties, drug-polymer interaction, drug crystallization, drug content, drug permeation through the skin, and coordination polymer network of the patches were investigated. In addition, skin irritation and adhesion potential in human subjects were assessed. Due to the ability of catechol groups to form interaction with the skin tissue, the patches containing PHI-cat and HA offered a considerably greater adhesion ability to human skin compared with the patches without catechol and commercial patches. Furthermore, the patches had good physical and chemical stability. Therefore, these catechol-functionalized patches may be potential transdermal drug delivery systems with excellent adhesive properties for the delivery of a drug through the skin.


Assuntos
Cetoprofeno , Humanos , Adesivos/química , Ácido Hialurônico , Preparações Farmacêuticas , Administração Cutânea , Acrilatos/química , Catecóis , Polímeros/química , Adesivo Transdérmico
12.
Molecules ; 27(20)2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36296590

RESUMO

A new synthesis of C5-substituted 1-alkyl-1H-indole-3-carboxylic esters is reported. A series of methyl 2-arylacrylate aza-Michael acceptors were prepared with aromatic substitution to activate them towards SNAr reaction. Subsequent reaction with a series of primary amines generated the title compounds. Initially, the sequence was expected to produce indoline products, but oxidative heteroaromatization intervened to generate the indoles. The reaction proceeded under anhydrous conditions in DMF at 23-90 °C using equimolar quantities of the acrylate and the amine with 2 equiv. of K2CO3 to give 61-92% of the indole products. The reaction involves an aza-Michael addition, followed by SNAr ring closure and heteroaromatization. Since the reactions were run under nitrogen, the final oxidation to the indole likely results from reaction with dissolved oxygen in the DMF. Substrates incorporating a 2-arylacrylonitrile proved too reactive to prepare using our protocol. The synthesis of the reaction substrates, their relative reactivities, and mechanistic details of the conversion are discussed.


Assuntos
Ésteres , Indóis , Estrutura Molecular , Indóis/química , Acrilatos/química , Aminas , Nitrogênio , Oxigênio
13.
ACS Macro Lett ; 11(10): 1207-1211, 2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36162407

RESUMO

Linear polyethylenes with a combination of incorporated in-chain keto as well as side-chain ester groups are formed by Ni(II)-catalyzed terpolymerization of ethylene, carbon monoxide, and methyl acrylate. These possess a random structure, with largely isolated nonalternating in-chain keto groups as well as ester-substituted units adjacent to the polyethylene chain, whereas the solid-state structure of polyethylene is retained. Molecular weights of the terpolymers (Mn ∼ 20.000 g mol-1) are predominantly determined by chain transfer after acrylate incorporation.


Assuntos
Monóxido de Carbono , Polietileno , Acrilatos/química , Catálise , Ésteres , Etilenos
14.
J Chromatogr A ; 1682: 463526, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36166884

RESUMO

In this research report, the post polymerization functionalization (PPF) of a carboxyethyl acrylate (CEA)-co-ethylene glycol dimethacrylate (EDMA) [poly-CEA-co-EDMA)] precursor monolith with 2-aminoanthracene was carried out in the presence of an organic solvent soluble carbodiimide, namely N,N´-dicyclohexylcarbodiimide (DCC), yielding the so-called anthracenyl-poly-CEA-co-EDMA monolith. This novel monolith proved to be an excellent monolithic stationary for reversed-phase capillary electrochromatography (RP-CEC) with hydrophobic and π-π interactions of a wide range of nonpolar solutes including those bearing aryl functional groups in their structures such as polycyclic aromatic hydrocarbons (PAHs), toluene derivatives and aniline derivatives as well as solutes carrying in their structures electron withdrawing substituents such as dinitrophenyl-amino acids (DNP-AAs) and di-DNP-AAs. The retention behaviors of the just mentioned solutes obtained on the anthracenyl-poly-CEA-co-EDMA monolithic column were compared to those obtained on octadecyl-poly-CEA-co-EDMA monolithic column prepared from the same carboxy-precursor monolith. The results demonstrated the superiority of anthracenyl column over the octadecyl column for the separation and enhanced selectivity for aromatic solutes since it provides not only hydrophobic interactions but also π-π interactions with aromatic nonpolar solutes.


Assuntos
Eletrocromatografia Capilar , Hidrocarbonetos Policíclicos Aromáticos , Acrilatos/química , Aminoácidos , Compostos de Anilina , Eletrocromatografia Capilar/métodos , Dicicloexilcarbodi-Imida , Interações Hidrofóbicas e Hidrofílicas , Ligantes , Metacrilatos/química , Hidrocarbonetos Policíclicos Aromáticos/química , Polietilenoglicóis , Solventes , Tolueno
15.
Biomacromolecules ; 23(10): 4241-4253, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36067415

RESUMO

The synthesis of protein-polymer conjugates usually requires extensive and costly deoxygenation procedures, thus limiting their availability and potential applications. In this work, we report the ultrafast synthesis of polymer-protein bioconjugates in the absence of any external deoxygenation via an aqueous copper-mediated methodology. Within 10 min and in the absence of any external stimulus such as light (which may limit the monomer scope and/or disrupt the secondary structure of the protein), a range of hydrophobic and hydrophilic monomers could be successfully grafted from a BSA macroinitiator, yielding well-defined polymer-protein bioconjugates at quantitative yields. Our approach is compatible with a wide range of monomer classes such as (meth) acrylates, styrene, and acrylamides as well as multiple macroinitiators including BSA, BSA nanoparticles, and beta-galactosidase from Aspergillus oryzae. Notably, the synthesis of challenging protein-polymer-polymer triblock copolymers was also demonstrated, thus significantly expanding the scope of our strategy. Importantly, both lower and higher scale polymerizations (from 0.2 to 35 mL) were possible without compromising the overall efficiency and the final yields. This simple methodology paves the way for a plethora of applications in aqueous solutions without the need of external stimuli or tedious deoxygenation.


Assuntos
Cobre , Polímeros , Acrilamidas/química , Acrilatos/química , Cobre/química , Oxigênio , Polimerização , Polímeros/química , Proteínas/química , Estireno/química , Água/química , beta-Galactosidase
16.
Sci Rep ; 12(1): 14215, 2022 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-35987777

RESUMO

Despite the large prevalence of diseases affecting cartilage (e.g. knee osteoarthritis affecting 16% of population globally), no curative treatments are available because of the limited capacity of drugs to localise in such tissue caused by low vascularisation and electrostatic repulsion. While an effective delivery system is sought, the only option is using high drug doses that can lead to systemic side effects. We introduced poly-beta-amino-esters (PBAEs) to effectively deliver drugs into cartilage tissues. PBAEs are copolymer of amines and di-acrylates further end-capped with other amine; therefore encompassing a very large research space for the identification of optimal candidates. In order to accelerate the screening of all possible PBAEs, the results of a small pool of polymers (n = 90) were used to train a variety of machine learning (ML) methods using only polymers properties available in public libraries or estimated from the chemical structure. Bagged multivariate adaptive regression splines (MARS) returned the best predictive performance and was used on the remaining (n = 3915) possible PBAEs resulting in the recognition of pivotal features; a further round of screening was carried out on PBAEs (n = 150) with small variations of structure of the main candidates from the first round. The refinements of such characteristics enabled the identification of a leading candidate predicted to improve drug uptake > 20 folds over conventional clinical treatment; this uptake improvement was also experimentally confirmed. This work highlights the potential of ML to accelerate biomaterials development by efficiently extracting information from a limited experimental dataset thus allowing patients to benefit earlier from a new technology and at a lower price. Such roadmap could also be applied for other drug/materials development where optimisation would normally be approached through combinatorial chemistry.


Assuntos
Acrilatos , Polímeros , Acrilatos/química , Aminas/química , Cartilagem , Estudos de Viabilidade , Humanos , Aprendizado de Máquina , Polímeros/química
17.
Carbohydr Polym ; 295: 119884, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35989019

RESUMO

Chitooligosaccharide (COS) as an emerging material carbohydrate polymer with huge potential in biomedical applications was prepared using a microwave-assisted process. The obtained COS exhibited reduced molecular weight (Mw) and higher water solubility in comparison to chitosan while preserving the main saccharide structure and same degree of deacetylation (DD). The optimized COS (13 kDa) was then used to synthesize a new family of COS-poly(ethylene glycol) diacrylate (PEGDA) derivatives based on aza-Michael addition of acrylate groups of PEGDA to the amine groups of COS in the absence of any exterior agents. The modulation of the reaction time, temperature, pH and NH2:acrylate molar ratio, had a strong influence on the Michael reaction progress. At higher degrees of conversion of acrylate groups, COS-PEGDA derivative formed gel with high biocompatibility towards human bone mesenchymal stem cells (hBMSCs). These COS-PEGDA hydrogels synthesized at mild conditions through a green chemistry are, therefore, an innovative system combining adequate biological performance, ease of preparation, and an environmentally friendly concept of production.


Assuntos
Quitosana , Polietilenoglicóis , Acrilatos/química , Quitosana/química , Humanos , Hidrogéis/química , Oligossacarídeos , Polietilenoglicóis/química
18.
ACS Macro Lett ; 11(9): 1079-1084, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-35984360

RESUMO

RAFT step-growth polymerization was previously demonstrated with monomers that bear low rate of homopropagation to favor the chain transfer process; by contrast, acrylates are known to be fast homopropagating monomers, thereby posing serious challenges for RAFT step-growth. Here, we identified a chain transfer agent (CTA) that rapidly yields single unit monomer inserted (SUMI) CTA adducts with a model acrylate monomer. Using a bifunctional reagent of this CTA, we successfully demonstrated RAFT step-growth polymerization with diacrylates, yielding linear polymer backbones. Furthermore, we achieved inclusion of functionality (i.e., disulfide) into RAFT step-growth polymer via a disulfide incorporated bifunctional CTA. Grafting from this backbone resulted in molecular brush polymers with cleavable functionality in each repeat unit of the backbone, allowing selective degradation to afford well-defined unimolecular species of two polymeric side chains. Given the wide selection of commercially available diacrylates, RAFT step-growth polymerization of diacrylates will further enable facile synthesis of complex architectures with modular backbones.


Assuntos
Acrilatos , Polímeros , Acrilatos/química , Reagentes de Ligações Cruzadas , Dissulfetos , Polimerização
19.
ACS Appl Mater Interfaces ; 14(34): 39548-39559, 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-35984897

RESUMO

Well-defined block copolymers have been widely used as emulsifiers, stabilizers, and dispersants in the chemical industry for at least 50 years. In contrast, nature employs amphiphilic proteins as polymeric surfactants whereby the spatial distribution of hydrophilic and hydrophobic amino acids within the polypeptide chains is optimized for surface activity. Herein, we report that polydisperse statistical copolymers prepared by conventional free-radical copolymerization can provide superior foaming performance compared to the analogous diblock copolymers. A series of predominantly (meth)acrylic comonomers are screened to identify optimal surface activity for foam stabilization of aqueous ethanol solutions. In particular, all-acrylic statistical copolymers comprising trimethylhexyl acrylate and poly(ethylene glycol) acrylate, P(TMHA-stat-PEGA), confer strong foamability and also lower the surface tension of a range of ethanol-water mixtures to a greater extent than the analogous block copolymers. For ethanol-rich hand sanitizer formulations, foam stabilization is normally achieved using environmentally persistent silicone-based copolymers or fluorinated surfactants. Herein, the best-performing fully hydrocarbon-based copolymer surfactants effectively stabilize ethanol-rich foams by a mechanism that resembles that of naturally-occurring proteins. This ability to reduce the surface tension of low-surface-energy liquids suggests a wide range of potential commercial applications.


Assuntos
Etanol , Água , Acrilatos/química , Hidrocarbonetos , Polímeros/química , Tensoativos/química , Água/química
20.
Acta Chim Slov ; 69(2): 405-418, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35861089

RESUMO

Taking cognizance of the medicinal significance and diverse functions of synthetic Morita-Baylis-Hillman adducts (MBHA), the title ligand was synthesized and purified through column chromatography. Cr+3, Mn+2, Co+3, Ni+2, Cu+2 complexes of the ligand were synthesized under basic conditions, subjected to characterization through spectral analyses and verified with the IR spectrum that was generated computationally by the DFT B3LYP method, with 6-311++ G (d,p) basis set and Hartree Fock (HF) B3LYP method in conjunction with 3-21G(d,p) basis set. Powder XRD helped to testify crystals of the complexes. Moreover, the antibacterial, and antioxidant characteristics of MBHA and its complexes were also established. All of them were found to be active antioxidants. The antibacterial activities, examined against S. aureus, E. coli, B. pumilis and S. typhi have revealed that its Cobalt complex has an excellent potential to act against all of them. Hence, these compounds maybe having potentialities for the discovery of new, cheaper and efficient drugs against various infectious diseases. The study also uncovers the first example of utilization of MBHA towards metal complex formation.


Assuntos
Complexos de Coordenação , Acrilatos/química , Antibacterianos/química , Antibacterianos/farmacologia , Cobalto/química , Escherichia coli , Ligantes , Testes de Sensibilidade Microbiana , Bases de Schiff/química , Staphylococcus aureus
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