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The present paper employs supported ruthenium nanoparticles alongside catalytic quantities of the radical initiator, which are proven to be capable of cyclooctene oxidation with green conditions, in the absence of solvent, with air as the main oxidant and without sacrificial reductant. The paper examines the effects of a range of radical initiators and how the products are distributed over time. Furthermore, the paper addresses the reaction pathways to the epoxides and allylic alcohol, the latter being the primary by-product, whilst also analysing the impact of the technique of synthesis, reaction time, and various supports. Catalyst activity can be markedly improved by adopting a sol-immobilization technique to synthesise the catalysts, with retention of selectivity to the epoxide.

An efficient and versatile copper-catalyzed intermolecular radical [3+2] annulation of thioamides with azobisisobutyronitrile (AIBN) is described. This two-component copper(II)-catalyzed transformation is achieved in one pot via cascade formation of C–S/C–N bonds through cyclization of an in situ generated N,S-acetal intermediate derived from a β-ketothioamide. This operationally simple method allows direct access to synthetically demanding thiazolidin-4-ones in good to excellent yields containing diverse functional groups of different electronic and steric nature. The readily available reaction partners, the avoidance of expensive/toxic reagents and a gram-scale synthesis are additional attributes of this strategy. AIBN plays a dual role as a radical initiator and an unusual source of a two-carbon coupling partner. Notably, the products possess Z stereochemistry with regard to the exo­cyclic C=C double bond at position 2 of the thiazolidine ring.

Ultrasound (US)-activated nanoagents capable of producing cytotoxic species have been promising for the treatment of deep-seated tumors; however, poor tumor uptake and insufficient generation of cytotoxic agents have largely limited their therapeutic efficacy in vivo. Herein, we report a hybrid FeCuS-lipid nanoparticle (AIBA@FeCuS-FeCO) by amphiphilic lipids-assisted emulsion of a free radical initiator (AIBA), a radical-sensitive CO donor (Fe3(CO)12), and radical-degradable FeCuS nanodisks for US-activated synergistic therapy of deep-located orthotopic gastric tumors in living mice. Upon US irradiation, AIBA@FeCuS-FeCO could be degraded and release cytotoxic AIBA radicals, CO, Fe2+, and Cu2+, allowing us to (1) enhance tumor uptake of AIBA@FeCuS-FeCO through CO-mediated vasodilation, (2) promote hydroxyl radical production and induce tumor ferroptosis via intracellular accumulation of Fe2+/Cu2+, and (3) kill tumor cells. Moreover, the subsequent administration of disulfiram (DSF) could further chelate with the liberated Cu2+, yielding toxic bis(N,N-diethyl dithiocarbamato)copper(II) chelates to synergize the therapeutic effect to ablate deep-seated orthotopic gastric tumors.

The unique properties of fluorine-containing organic compounds make fluorine substitution attractive for the development of pharmaceuticals and various specialty materials, which have inspired the evolution of diverse C-F bond activation techniques. Although many advances have been made in functionalizations of activated C-F bonds utilizing transition metal complexes, there are fewer approaches available for nonactivated C-F bonds due to the difficulty in oxidative addition of transition metals to the inert C-F bonds. In this regard, using Lewis acid to abstract the fluoride and light/radical initiator to generate the radical intermediate have emerged as powerful tools for activating those inert C-F bonds. Meanwhile, these transition-metal-free processes are greener, economical, and for the pharmaceutical industry, without heavy metal residues. This review provides an overview of recent C-F bond activations and functionalizations under transition-metal-free conditions. The key mechanisms involved are demonstrated and discussed in detail. Finally, a brief discussion on the existing limitations of this field and our perspective are presented.

A visible light-mediated heterogeneous photocatalytic cyanomethylarylation of alkenes with acetonitrile has been established using K-modified carbon nitride (CN-K) as a recyclable semiconductor photocatalyst. This protocol, employing readily accessible alkyl N-hydroxyphthalimide (NHPI) ester as a radical initiator, allows the efficient construction of a broad array of structural diverse nitrogenous heterocyclic compounds including indolines, oxindoles, isoquinolinones, and isoquinolinediones.

Polymerization-induced self-assembly (PISA) is a widely used technique for the synthesis of nanoparticles with various morphologies including spheres, worms, and vesicles. The development of a PISA formulation based on reversible addition-fragmentation chain transfer (RAFT) aqueous emulsion polymerization offers considerable advantages such as enhanced rate of polymerization, high conversion and environmentally friendly conditions. However, this formulation has typically produced spheres as opposed to worms and vesicles. Herein, we report the formation of vesicle morphology by increasing the RAFT end-group hydrophobicity of the macromolecular chain transfer agent or manipulating the radical initiator concentration used in the aqueous emulsion polymerization PISA formulation. Additionally, decreasing the molecular weight of the hydrophobic polystyrene domain in these vesicles leads to the formation of worms. This work demonstrates that RAFT end-group hydrophobicity and radical initiator concentration are key parameters which can be exploited to enable access to sphere, worm, and vesicle morphologies via the RAFT aqueous emulsion polymerization.

Given the recent findings of exogenous radical initiator/catalyst-free reversible addition–fragmentation chain transfer (RAFT) radical polymerization under both UV and visible light irradiation, the effect of standard laboratory lighting conditions (fluorescent tube lights) on traditional RAFT reactions, that is, those conducted in the presence of a thermally activated radical initiator, remains unknown. This is investigated in the current study, where a significant “photoenhancement” is observed for most cases under typical RAFT reaction conditions, indicating that fume hood lights can contribute to the generation of radicals in RAFT reactions. Given the observed emission spectrum of a typical fluorescent light source, the photoenhancement is proposed to occur through a visible light activation pathway. These findings are crucial for ensuring maximum reproducibility of controlled polymerizations conducted in the presence of typical sources of irradiation encountered in a standard chemical laboratory.

The free radical and controlled radical polymerization of sodium 4-vinylbenzenesulfonate using graphene oxide as a radical initiator was studied. This work demonstrates that graphene oxide can initiate radical polymerization in an aqueous solution without any additional initiator. Poly(sodium 4-vinylbenzenesulfonate) obtained via reversible addition–fragmentation chain transfer polymerization had a controlled molecular weight with a very narrow polydispersity ranging between 1.01 and 1.03. The reduction process of graphene oxide as well as the resulting composite material properties were analyzed in detail.

A simple method has been developed for the synthesis of ­3-(2-oxo-2-phenylethylidene)-3,4-dihydroquinoxalin-2(1H)-one and ­3-aryl-quinoxalin-2(1H)-one derivatives through C–H activation of quinoxalin-2(1H)-ones by peroxides and iodide. In this protocol, the per­oxide (TBPB) serves as both the radical initiator and aryl source, realizing arylation of quinoxalin-2(1H)-one in a one-step reaction. The methodology has the advantages of being a metal-free strategy and having broad functional group tolerance.

In this work, the first diboron reagent initiated atom-transfer radical cyclization was reported, in which the boryl radicals were generated by the homolytic cleavage of a B–B single bond weakened by the coordination of Lewis base. To clarify the role of carbonate and DMF in the cleavage of B–B bond, we calculated the free energy diagram of two pathways by density functional theory (DFT) investigations. The DFT calculation showed that the presence of carbonate facilitates the B–B bond cleavage to form boron radicals, which can be further stabilized by DMF. Subsequent atom-transfer cyclization initiated by stabilized dihydroxyboron radical is also energetically favored.

Objective: The objective of the present investigation was the synthesis of grafted co-polymer gum mastic using acrylamide as the monomer. Methods: 3-factor 3-level response surface Box-Behnken design, which requires 15 runs including three replicates of the central run, was used for the synthesis of graft copolymers of mastic gum with acrylamide using ceric ammonium nitrate as the free radical initiator. The critical synthesis and process parameters; CSPP (A = concentration of monomer, B = concentration of initiator and C= Temperature) to generate design space and optimize formulation with an aim to obtain critical quality attributes (CQA, Y1 =% Yield, Y2 =% Grafting, Y3 =% grafting efficiency). Result: Formulation F14 having a maximum % yield of 75.89% with % grafting of 210% and % grafting efficiency 51.57% was selected as best. Conclusion: The microwave-assisted grafted mastic gum was prepared successfully and optimized by using Box Behnken design.

The surface functionalization of oxide-free hydrogen-terminated silicon (Si−H) enables predictably tuning its electronic properties, by incorporating tailored functionality for applications such as photovoltaics, biosensing and molecular electronics devices. Most of the available chemical functionalization approaches require an external radical initiator, such as UV light, heat or chemical reagents. Here, we report forming organic monolayers on Si–H surfaces using molecules comprising terminal alcohol (–OH) groups. Self-assembled monolayer (SAM) formation is spontaneous, requires no external stimuli–and yields Si–O–C covalently bound monolayers. The SAMs were characterized by X-ray photoelectron spectroscopy (XPS) to determine the chemical bonding, by X-ray reflectometry (XRR) to determine the monolayers thicknesses on the surface and by atomic force microscopy (AFM) to probe surface topography and surface roughness. The redox activity and the electrochemical properties of the SAMs were studied using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The availability and the ease of incorporating OH groups in organic molecules, makes this spontaneous grafting as a reliable method to attach molecules to Si surfaces in applications ranging from sensing to molecular electronics where incorporating radical initiator setups is not accessible.

Cross-dehydrogenative coupling reactions provide a method to construct new chemical bonds by direct C–H activation without any pre-functionalization. Compared to functionalization of a C–H bond α- to ether oxygen, α- to carbonyl, or at a benzylic position, functionalization of unactivated hydrocarbons is difficult and often requires high temperatures, a transition-metal catalyst, or a superstoichiometric quantity of volatile, toxic, and explosive tert-butylhydroperoxide. Here, a cross-dehydrogenative C–O coupling reaction of N-hydroxyphthalimide with unactivated alkanes, nitriles, ethers, and thioethers has been realized by using iodobenzene diacetate as the radical initiator. The current protocol enables efficient functionalization of unactivated hydrocarbons and nitriles through inert C(sp3)–H bond activation under mild reaction conditions. O-substituted NHPI derivatives are generated in good yields under metal-free conditions. Robust and selective C–H functionalisation of alkanes remains a challenge. Here, iodine(III) mediates the radical coupling of N-hydroxyphthalimide and unactivated C(sp3)–H bonds in a range of cyclic and acyclic alkanes.

Copolymers of N,N-diallyl-Nʹ-acetylhydrazine and N,N-diallyl-Nʹ-benzoylhydrazine with acrylic acid, acrylonitrile, and acrylamide were synthesized by radical copolymerization in the presence of a radical initiator azobisisobutyronitrile. The borohydride method was used to produce new polymer nanocomposites containing silver nanoparticles 31–55 nm in size, stabilized by synthesized copolymers of N,N-diallyl-Nʹ-acylhydrazines. The presence of heteroatomic fragments and functional groups (carboxyl, amide, nitrile, acetyl, benzoyl, hydrazine) in the polymer chain promotes specific interaction with silver particles, regulating the particle size at the nanoscale and ensuring their uniform distribution in the polymer matrix. Structural features of nanocomposites were investigated using UV, IR, NMR spectroscopy and scanning electron microscopy. The produced nanocomposites exhibit cytotoxic activity against MS melanoma cells and RD rhabdomyosarcoma cells and are promising as new-generation drugs intended for the treatment of cancerous tumors.

In this work, the epoxy groups of poly (ethylene terephthalate) PET copolymers grafted with glycidyl methacrylate (GMA) were modified with ethylenediamine (EDA) to form exclusive adsorbent for removal of congo red (CR) and acid violet7 (AV-7) in the aqueous environment. The graft copolymers (GMA-g-PET) were synthesized with different grafting yield by a radical polymerization process with using benzoyl peroxide (Bz2O2) as radical initiator. Amination of GMA-g-PET fibers using EDA was studied in different solvents, and maximum yield (w/w %) was obtained in the toluene. The grafted and modified fibers were analyzed by CHNS organic elemental analyzer, scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and nuclear magnetic resonance spectroscopy (13C-NMR). By SEM analysis, the morphological changes have been shown after grafting. The chemical changes after grafting and addition of EDA to the fibers have been proven with FTIR, NMR and elemental analysis. The thermal properties of the grafted and aminated fibers were researched with thermogravimetric analysis and differential scanning calorimeter analysis. The removal of dyes by the EDA-GMA-g-PET fibers was investigated in aqueous medium at different conditions. Optimum conditions of different parameters such as pH of medium, graft yield of GMA on the fibers, adsorption duration, initial concentration of dye molecules and effect of graft yield on amination reaction were examined. The optimum pH of CR and AV-7 removal was found 5 and 3, respectively. The removal yield was found about 100% for both dyes while initial concentration of dyes was changed from 10 to 400 mg/L. Adsorbed dyes with the fibers were desorbed with 1 M NaOH at room conditions.

In this paper, copolymerization of methyl methacrylate (MMA) with n-butyl acrylate (BA) in a bubble column reactor using benzoyl peroxide as free radical initiator, at a temperature over 85 °C, is presented. This mode of copolymerization keeps an inert atmosphere throughout the entire reaction and contributes to proper mixing of the monomers. Higher pressure of the bubbling ensures the faster contact of the species, and a higher conversion was obtained in a shorter reaction time. The conversion of monomer at 124 Pa after 210 min is total, which is particularly noteworthy due to the absence of residual monomer that represents hazardous compounds, with negative impact upon employees and end-user safety. Higher conversions are obtained at 96 °C, 124 Pa nitrogen bubble pressure, 60/40% moles monomer ratio BA/MMA and 2% POB. The molar mass Mw, Mn and PDI decrease with the increase in temperature quite linearly. In the absence of nitrogen bubbling, the copolymer composition is approximately the same as in the feeding mixture. The corrosion protection efficiency of steel painted with these acrylic coatings was carried out by means of OCP and potentiodynamic polarization testing and electrochemical impedance spectroscopy (EIS).

An alternative approach toward understanding and advancing hydrogel-based single walled carbon nanotube (SWNT) purification is described and employed. Experimental and atomistic modeling analysis of the leading hydrogel for SWNT purification, Sephacryl S200, affords creation of gels that mimic its behavior in terms of dependent SWNT interaction and SWNT purification properties. This achievement introduces a generalized approach toward optimization of SWNT purification media with respect to the components of Sephacryl. Here, the role of the radical initiator ammonium persulfate (APS) in hydrogel-based SWNT purification is explored through synthesis and characterization of gels containing varied APS concentration, and thus, varied amounts of covalently embedded charged organosulfate groups (R–SO4-). The presence of these moieties plays a significant role in SWNT-gel interactions: at decreasing APS concentration SWNT uptake is increased, the chiral profiles of purified SWNT are altered, and a greater fraction of adsorbed material is recovered. Tailored hydrogels containing minimal APS exhibit improved SWNT adsorption vs. Sephacryl. These findings warrant proposition of a four-step qualitative model that deconvolutes electrostatic and steric effects within SWNT/surfactant/hydrogel systems. Collectively, this work demonstrates enhanced methodology for hydrogel-based SWNT purification and lays the foundation for further optimization of the gel medium.

In this study an easy template was devised for the fabrication and microstructural control of ligand-chelated, silica–zirconia-based composite membranes with a thickness of less than 400 nm. Hybrid materials with crosslinking between the organic moieties were successfully fabricated via the sol–gel co-condensation of 3-(trimethoxysilyl)propyl methacrylate and zirconium(IV) butoxide chelated via acetylacetone and allyl acetoacetate ligands using an azobisisobutyronitrile radical initiator as a crosslinking agent. Characterization of the films and gels via FTIR, XRD and thermogravimetry indicated that both the polymerization and hybridization of the networks was achieved. Gas permeation experiments showed that the organic crosslink-derived membranes possess molecular sieving properties (H2 permeance: ≈10−7 mol m−2 s−1 Pa−1; H2/N2 selectivity: ≈20–30) that are superior to those of non-crosslink-derived membranes (H2 permeance: ≈10−7 mol m−2 s−1 Pa−1; H2/N2 selectivity: ≈7–11). Quantitative analysis of the microstructures of the membranes based on the permeation behaviors of H2 and N2 revealed that organic crosslinking led to significant control of the microstructural characteristics of the membranes.

We synthesized a dual fluorogenic system based on a boron-dipyrromethene (BODIPY) dye coupled with a paramagnetic 2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO) nitroxide. Electron exchange facilitates the non-radiative relaxation of the singlet state of the chromophore, partially quenching the fluorescence from the BODIPY moiety. Nonetheless, the system can be ‘activated’ in solution or thin polymer films by ultraviolet (UVA) light in the presence of a free radical initiator. UVA illumination promotes the decomposition of the initiator, resulting in the release of a carbon-centered free radical. The dye-TEMPO probe can concomitantly trap the radical or undergo H-abstraction. Both processes consequently turn on the fluorescence and are reversible in nature. We used this protocol to optically imprint a fluorescent pattern on a surface. Moreover, we investigated metal-enhanced fluorescence (MEF) effects by silver nanostructures (AgNP) as a means to improve the performance of our molecular strategy for fluorescence activation. Overall, this work contributes toward the development of improved nanoparticle–dye systems for applications of light-activated fluorescence such as multicolour fluorescence patterning and microscopy, where shorter reaction times, milder conditions, reversibility and a more diverse selection of both excitation sources and emission wavelengths are beneficial.

Methyl methacrylate (MMA) was successfully grafted onto cellulose nanofibers (CNFs) at room temperature in an emulsion system using a diethyl(1,10-phenanthroline N1,N10)zinc(II) complex (Phen-DEZ) with oxygen as the radical initiator. The effects of reaction temperature, initiator concentration, and monomer content on the grafting reaction were investigated. The molecular weight of the non-grafted PMMA, which was produced during graft polymerization, was more than 1 million, as determined by size exclusion chromatography. The PMMA-grafted CNFs were analyzed by Fourier transform infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy, which confirmed the grafting of PMMA on the nanofiber surface. The study presents a strategy for the grafting of high-molecular weight PMMA onto CNFs in an emulsion system using Phen-DEZ and O2.

A method of making block copolymers utilizing free-radical polymerization and subsequent polymer conjugation is described. A disulphide functional radical initiator was used to polymerize methacrylic acid and 3-acrylamidophenylboronic acid. After purification, the disulphide bond of the end group was cleaved, revealing a thiol group which was used for subsequent conjugation to a polylactide containing the complementary maleimide functional group. The method is versatile and can be applied to the synthesis of various block copolymers without requiring the use of controlled/living radical polymerization methods.

In order improve the fuel cell performance of a free-standing graphene oxide (GO) membrane, the impacts of both the additional oxidation of GO and the modification with vinilsulfonic acid were investigated. The modification with vinilsulfonic acid was conducted with and without adding potassium persulfate, K2S2O8, which is a radical initiator for the polymerization of vinylsulfonate. A total of six types of free-standing GO membranes with and without the oxidation and/or the modification were prepared. The oxidation and the modification additively increased the proton conductivity, and the oxidation significantly improved the durability of the fuel cell performance at 30 °C. The membrane of GOhvsi, of which GO was oxidized and modified with the initiator, showed very high in-plane proton conductivities at 30 °C, i.e., 0.54 S cm−1 at RH 100%. The H2–O2 fuel cell using GOhvsi showed maximum power densities as high as 136 mW cm−2 and 184 mW cm−2 at 30 °C and 50 °C, respectively. The performance at 30 °C was stable for more than 20 h. The improved durability by the oxidation was attributed to the increased defects of carbon based on an XPS analysis. The TPD-MS analysis suggested that the oxygenated functional groups at the defects would increase the binding strength.

We have developed a new radical-mediated alkoxypolyhaloalkylation of styrenes with polychloroalkanes and alcohols for the facile synthesis of complex polyhaloalkanes. 4-Methoxybenzenediazonium tetrafluoroborate is a good radical initiator for this transformation. This protocol is well applied to the late-stage functionalization of complex molecules, including vitamin E, estrone and cholesterol derivatives.

The use of organic–inorganic hybrid nanoparticles will enable a control of the characteristics of both the nanoparticles and constructed fine structures. In this study, we report the synthesis of acrylate-intercalated layered manganese, cobalt, and nickel hydroxide nanoparticles and their assembly into ordered mesoporous structures. Polymerization of the intercalated acrylates takes place by means of a radical initiator. The formed organic network improved the thermal stability of the layered hydroxides, which results in thermally robust mesoporous structures. Additionally, it is found that the polymerization can be initiated and progressed at 200 °C without any initiators for the layered nickel hydroxide system. This allows for the scalable solid-state thermal polymerization of intercalated acrylates and the formation of thermally robust hierarchically ordered meso/macroporous powders as well as mesoporous films. The electrochemical characterization reveals that the thermally robust mesoporous films having regulated mesopores allow for the effective diffusion of molecules/solvent compared with the films having collapsed mesoporous structures., The present work is partially supported by JSPS KAKENHI Grant Number JP20K15368, JSPS Core-to-Core Program, MEXT Leading Initiative for Excellent Young Researchers, the Foundation for the Promotion of Ion Engineering, International Network on Polyoxometalate Science at Hiroshima University, and the Izumi Science and Technology Foundation (2019-J-112).

A metal-free C–C bond activation strategy of 1,3-diynes has been described via an “extrusion and recombination” approach, which delivered structurally important 1,2-diketones. This phenomenon was performed using tetra-n-butylammonium iodide (TBAI) as a catalyst and peroxide as a radical initiator and oxidant. The C–C bond activation follows sequential oxidation, extrusion of CO2 as a byproduct and sewing of the molecular fragments to release the desired products. This protocol was elaborated towards unsymmetrical 1,2-diketones via selective generation and recombination of distinct molecular fragments. The proposed mechanism has been verified using adequate control experiments and DFT calculations.

The SF5Cl radical addition on unsaturated compounds was performed using an air-stable amine–borane complex as the radical initiator. This method showed to be complementary to the classic Et3B-mediated SF5Cl addition on alkenes and alkynes. A total of seven alkene and three alkyne derivatives were tested in the reaction, with yields ranging from 3% to 85%.

Firstly, a newly developed bacteria brans (BB) /poly (acrylic/acrylamide/2-acrlylamido-2-methyl-1-propanesulfonic acid) (AA/AM/AMPS) hydrogel was reported, which cross-linked by N, N’-methyl-enebisacrylamide in the presence of potassium persulfate as a free radical initiator. The BB, a waste after the cultivation of the edible fungus, is composite of lignin, cellulose and other carbohydrates, which are beneficial to enhance the water absorbency properties of the super-absorbent hydrogel. Secondly, the chemical structure and morphologies of the hydrogel were characterized by ourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM) and the thermogravimetric analysis (TGA). The results confirmed that superabsorbent comprised a coarse surface and the porous network structure with carboxylate, carboxamide and sulfate. Finally, the swelling behaviors of the BB/P (AA/AM/AMPS) hydrogel have been studied, achieving favourable water absorbency properties (589 g/g). The effect of swelling behaviors of the hydrogel on the pH value and the concentration of the salt solution were also studied. This work improves the swelling behaviors of the hydrogel. Importantly, it provides the way to devise the hydrogel with environmental compatibility and low-cost, which is useful in many potential applications, such as agriculture.

2, 4-dichloro-5’fluoro-1-ene-2-(4-hydroxyphenyl) phenone (EHP) was synthesized using 4- hydroxybenzaldehyde and 2,4-dichloro-5-fluoro acetophenone (DFA). 4-[3-(2, 4-dichloro-5-fluorophenyl)-3-oxoprop-1-en-1-yl]phenyl acrylate (EAP) was prepared by reacting EHP with acryloyl hloride using ethyl methyl ketone (EMK) as a solvent in the presence of triethylamine (TEA) as a base at 0-50. Poly (EAP) was prepared by solution polymerization technique using benzoyl peroxide (BPO) as a free radical initiator and EMK as a solvent at 70 ± 10. EHP, EAP and poly (EAP) were characterized by Infrared, proton NMR and 13C NMR techniques. Anti-microbial activity of the DFA, EHP, EAP and poly (EAP) were tested on three different ATCC microorganisms (E.coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853 and Salmonella Typhi ATCC 6539). The minimum concentration of the drug needed to inhibit the growth of the bacteria was estimated using photometry assay method. Keywords: Chalcones, Antimicrobials, Polymerization, Dimethyl sulphoxide.

Crosslinking characteristics and surface mechanical properties of radical and urethane dual-curable clearcoats were investigated by changing quantities of C=C bonds and OH groups in hydroxyl-functionalized urethane methacrylate oligomer (HFUMO) resins. The isocyanate blocked with a thermal radical initiator (BL-Tri-cHD) was utilized as a hybrid dual-curable thermal crosslinker to expedite the crosslinking of the main resin. The dual reactions between various HFUMO resins and BL-Tri-cHD were efficiently monitored via Fourier transform infrared spectroscopy to measure the peaks before and after curing. The influence of each functional group (C=C bond or OH group) in HFUMO on the initiation and development of crosslinking in dual-curable clearcoats was investigated by real-time measurements using rotational rheometer and rigid body pendulum tester. Temperature-dependent mechanical properties of cured films were confirmed through dynamic mechanical analysis. The surface mechanical properties of cured clearcoat films were also evaluated via the nanoindentation and nanoscratch tests, demonstrating the variation in surface resistance with respect to the C=C bond content and the OH value. Thus, the low-temperature curing and desired mechanical properties of clearcoats can be optimized by adjusting the content of the functional groups in a HFUMO and using a dual-curable crosslinker to simultaneously generate both radical and urethane crosslinking reactions.

Controlled polymerization of styrene (both self-initiated and initiated with azobisisobutyronitrile) in the presence of Blatter’s radical at 125 °C was studied. When using the radical initiator, there is no induction period. On the basis of UV spectroscopy and MALDI massspectrometry studies, it was established that the Blatter radical is completely consumed at the initial stage of the polymerization, inserting into almost all macromolecules. The prepared polystyrene exhibits the ability to reinitialization in post-polymerization and the synthesis of block copolymers.

The C(sp3)–H bond is found widely in organic molecules. Recently, the functionalization of C(sp3)–H bonds has developed into a powerful tool for augmenting highly functionalized frameworks in organic synthesis. Based on the results obtained in our group, the present account mainly summarizes recent progress on the functionalization of C(sp3)–H bonds of aliphatic alcohols, ketones, alkyl nitriles, and ethers with styrene or cinnamic acid using tert-butyl hydroperoxide (TBHP) as a radical initiator.1 Introduction2 Oxidative Coupling of Styrenes with C(sp3)–H Bonds3 Decarboxylative Cross-Couplings of α,β-Unsaturated Carboxylic Acids with C(sp3)–H Bonds4 Conclusions

Herein we present facile and green two-steps method for the fabrication of silver-carboxylated nanocellulose (Ag-ONCs) nanocomposite. Respecting the Circular Economy principle, the ONCs are prepared starting from the treatment of agriculture bagasse waste with ammonium persulfate--APS. This method permits to obtain ONCs fibers with rod or whisker shapes, with size and length in the range 6-10 nm and 90-150 nm, respectively. Ag-ONCs are then fabricated using a green photochemical approach. The UV irradiation works as radical initiator for the silver reduction, in water solution and at room temperature. The ONCs act as a template and reducing agent for silver nanoparticles formation, due to the specific hydroxyl and carboxyl groups on the cellulose surface. The structural and morphological properties of ONCs and Ag-ONCs nanocomposite are well evaluated by FT-IR, XRD, UV-Vis, AFM, SEM and TEM characterizations. The results showed that well crystalline, quasi-spherical silver nanoparticles of about 4-10 nm dispersed in the ONCs matrix are fabricated. Qualitative antibacterial tests towards gram negative (Escherichia coli and Pseudomonas aeruginosa) and gram positive (Staphylococcus aureus and Bacillus subtilis) bacteria are carried out and the results demonstrated that the Ag-ONCs inhibit the bacteria growth, with 12-14 mm of inhibition zone for both the bacteria groups. Also, quantitative antibacterial tests for E. coli, chosen as representative for its diffusion, are carried out and the bacteria growth rate and the inhibition rate for Ag-ONCs at different concentrations are evaluated. The analysis showed that the MIC (minimum inhibition concentration) for Ag is about 110 µg/mL for E. coli. These results demonstrated that the Ag-ONCs possess suitable and promising antibacterial behavior and could be used for industrial and technological application.

The free-radical racemization of non-activated amines is a powerful tool for process design in the pharmaceutical industry, allowing the recycling of undesired enantiomers after chiral separation. This paper describes the development of the free-radical racemization of a key API intermediate in a continuous flow reactor. Upon development, a significant reduction of the solvent usage and radical initiator was made possible thanks to the conversion into a continuous flow mode. This intensification positively impacted both the environmental footprint and the safety of the reaction as well as maintaining satisfactory productivity.

In this study, a nanogel-hydrogel hybrid was synthesized to improve drug delivery system performance. First, poly (acrylic acid-N-isopropylacrylamide) nanoparticles were synthesized using acrylic acid, N-isopropylacrylamide, sodium dodecyl sulfate, and MBA in the presence of APS as a radical initiator. Then the synthesized (A-N) nanogel was added to a solution of chitosan in acetic acid and (A-N) nanogel/ CTS-A hydrogel was synthesized in the presence of AA, MBA and ASP. (A-N) nanogel/ CTS-A hydrogel was characterized by IR, SEM, EDX, TEM, DLS, TGA, DTG and BET techniques. Doxorubicin (DOX) solution was used to evaluate drug loading capacity and the amount of drug-loaded was calculated using UV analysis. Drug release behavior was investigated by placing DOX-loaded (A-N) nanogel/ CTS-A at different temperature and pH ranges. Our research indicated the drug release for both carriers was controlled by diffusion mechanism but, increasing of temperature had not influenced the drug release mechanism. However, this study suggests that by trapping nanoparticles in a hydrogel system, drug carriers with higher absorption capacity and slower kinetic release can be created.

Three novel multifunctional additives (MFAs), poly(alkyl acrylate-co-maleic anhydride)-based amide copolymers, were synthesized by the reaction between intermediate alkyl acrylate-co-maleic anhydride and three different amines, viz. octylamine (MFA 1), dodecylamine (MFA 2), and octadecylamine (MFA 3). Additives were successfully prepared by the polymerization route using benzoyl peroxide (Bz2O2) as a free radical initiator. Analytical techniques such as Fourier transform infrared, nuclear magnetic resonance, and gel permeation chromatography were used to characterize the synthesized polymeric compounds. Polyol was taken as reference base oil for performance evaluation of the synthesized polymers as multifunctional additive for viscosity index improver, pour point depressant, anti-wear, anti-friction, detergent–dispersant, and anti-corrosion properties. MFA 1 reflected the best performance as detergent–dispersant and anti-corrosive additive with observed increment of ~ 48% and ~ 54%, respectively, in comparison with blank polyol. MFA 3 showed the best viscosity index improving property which enhanced the viscosity index of polyol base oil from 191.85 to 250.45 at 3000 ppm. It also showed best tribological performance in 3000 ppm concentration at which the average wear scar diameter and average friction coefficient values decrease to 482 µm and 0.0823 from the 690 µm and 0.1276 for blank polyol.

The first metal-free and facile radical addition/cyclization of simple alcohols with diaryl(arylethynyl)phosphine oxides has been described with AIBN as radical initiator, affording an efficient an...