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In this study, a nanohybrid based on montmorillonite (oMMT2) was prepared through a two‐step method using Arquad MCB‐80 and 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO) as intercalation agents. The nanohybrid exhibited a basal spacing of 31.5 Å, which contained approximately 12.3% of Arquad MCB‐80 and 31.6% of DOPO. Various amount of oMMT2 nanohybrid was incorporated into a flame‐retardant polyethylene system containing aluminum trihydroxide and red phosphorus with a constant total additive content of 20 wt%. The dispersibility of oMMT2 in the composite matrix was evaluated by energy dispersive x‐ray mapping and x‐ray diffraction analyses. At a content of 3 wt% in the nanocomposite, oMMT2 showed a highly exfoliated state, while at a 5% content, a partially exfoliated and intercalated state was observed. A synergistic flame‐retardant effect between the nanohybrid and the mixture of aluminum trihydroxide and red phosphorus was found. The nanocomposite loading 3 wt% oMMT2 demonstrated the best flame retardancy, achieving a V‐0 rating of the vertical burning test with a limiting oxygen index of 27.6%. Moreover, the addition of the low oMMT2 contents (≤3 wt%) improved the mechanical properties of the flame‐retardant composite. [ABSTRACT FROM AUTHOR]

Dihydrogen, commonly named 'hydrogen', is a carbon–neutral and renewable fuel meeting environmental regulations in transportation and industrial production. Hydrogen is currently employed in fuel cells, hydrogen vehicles, and as an efficient energy carrier due to its high energy capacity of 121 kJ per g. Here we review hydrogen production by steam reforming of alcohols including methanol, ethanol, propanol, glycerol and butanol, with focus on catalysts, mechanisms, and analytical methods to characterize deposited carbon. In general, Ru- and Rh-based catalysts show efficient performance with almost 100% feedstock conversion and up to 89% of hydrogen yield, while Ni and Co catalysts exhibit lower ethanol conversion in the range of 40–100% depending on operating conditions. Nevertheless, Ni and Co catalysts have been mainly chosen as active metals for alcohols steam reforming due to their lower cost. [ABSTRACT FROM AUTHOR]

High fire‐resistance polypropylene (PP) composites were prepared by using environment‐friendly flame retardants including expandable graphite (EG), red phosphorus (RP), and magnesium hydroxide (MH). Synergism between EG, RP, and MH on the thermo‐oxidation behavior and flame resistance of PP was found. The incorporation of MH and RP formed highly thermally stable mixtures of magnesium phosphates consisting of Mg3(PO4)2, Mg(PO3)2, and α‐Mg2P2O7 at both amorphous and crystalline phases in the burning process. The mixture not only covered the surface of burning materials but also could reinforce the char structure of the PP/EG composites, thereby significantly enhancing the condensed phase flame retardant mechanism of the composites. Mass ratios of the flame retardants were also optimized to obtain the composite with the highest flame retardant efficiency. The result revealed that the combination of EG, RP, and MH in PP at MH/RP mass ratio of 3/2 with only a total additive content of 18 wt.% could make its limiting oxygen index (LOI) increase from 16.8% to 27.2% and the UL‐94 rating was improved from none to V‐0. In addition, the mechanical properties of the composites were improved via the surface treatment of MH and RP with calcium stearate and silicone oil, respectively. [ABSTRACT FROM AUTHOR]

Controlled polymer techniques have significantly advanced thanks to using the energy of light to control radical polymerizations. Although many photocatalysts (e.g. metal catalysts, organocatalysts, semiconductor materials, etc.) have been reported, most of these catalysts are still expensive synthetic, trace oxygen-sensitive, and often use UV source light to create the activator to the polymerization. Metal–organic frameworks (MOFs), consisting of metal clusters coordinated to organic ligands, are rising stars as heterogeneous photocatalysis for living radical polymerization techniques because they have many advantages such as facile operation, low toxicity, air stability, and sustainability. Herein, we reported a robust and versatile Fe(III)-MOF, MIL-100(Fe), as a heterogeneous photocatalyst for controlled atom transfer radical polymerization (ATRP) under visible light and natural sunlight without any additives. Moreover, controlled polymerization was also achieved in the presence of oxygen. Many polymer compositions including homopolymers, random copolymers, and diblock copolymers were successfully prepared with well-defined molecular weights and narrow dispersity index values (Đ < 1.5). Most importantly, the heterogeneous Fe(III)-MOF catalyst was allowed easily separated and can be reused again for ATRP reaction for ten cycles that maintains the high photocatalytic efficiency. This method provides a new avenue for exploring MIL-100(Fe) as a low-cost, high-performance, and sustainable catalyst for photo-ATRP. [ABSTRACT FROM AUTHOR]

A novel cyanine compound based on the conjugated perylene‐benzothiazole system (PBI) as a colorimetric and fluorometric dual‐channel sensor for cyanide (CN−) detection was synthesized and characterized via UV‐vis and fluorescence spectroscopy. PBI exhibited a high sensitivity and rapid optical response for CN− due to the intramolecular charge transfer (ICT) mechanism. The detection limit of PBI for CN− was 1.15×10−7 M in the mixture of DMSO/H2O (1 : 1, v/v). Moreover, probe PBI demonstrated high selectivity and sensitivity for CN− over other common anions, including Cl−, Br−, F−, I−, AcO−, ClO4−, HSO4−, SO42−, NO2−, NO3− and SCN−. This work provided a simple and effective approach to trace the toxic CN− ion with rapid response, high selectivity, and sensitivity that is possibly applied in environmental control and agricultural management. [ABSTRACT FROM AUTHOR]

In this research, diblock copolymers based on the rod segment of regioregular poly(3-hexylthiophene) (P3HT) and a coil segment of poly(2-(dimethylamino)ethyl methacrylate-random-1-pyrenylmethyl methacrylate) (P(DMAEMA-r-PyMA)) was synthesized successfully by Grignard metathesis (GRIM) method and atom transfer radical polymerization reaction (ATRP). The obtained copolymer was well-defined with an average molecular weight of 11300 g/mol and low polydispersity below 1.5. The polymer structure was determined via gel permeation chromatography (GPC), Fourier transform infrared (FTIR) spectroscopy and proton nuclear magnetic resonance (1H NMR) spectroscopies. In addition, the optical and thermal properties of polymers were characterized via ultraviolet–visible (UV–Vis), differential scanning calorimetry (DSC) spectroscopy and fluorescence spectroscopy. Interestingly, P3HT-b-P(DMAEMA-r-PyMA) was examined as a possible chemosensor for trace detection of the trinitrotoluene (TNT) explosive. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks have been extensively studied in catalysis owing to their unique physicochemical properties. However, this class of materials has not yet been directly applied to the catalytic ozonation of organic pollutants. In this study, MIL-100(Fe) was synthesized by a solvothermal method and characterized by powder X-ray diffraction, thermogravimetric analysis, Fourier-transform infrared spectroscopy, N2 adsorption–desorption and scanning electron microscopy. A range of reaction conditions such as pH, solute concentration and catalyst content were applied to investigate the catalytic activity of our MIL-100(Fe) sample for the ozonation of p-nitrophenol in water. According to the experimental results, at a neutral initial pH, the catalytic ozonation of p-nitrophenol proceeded mainly through radical reactions, whereas in the absence of the MIL-100(Fe) catalyst, ozone could react with p-nitrophenol via the direct reaction pathway. The catalyst achieved a conversion of up to 98% and chemical oxygen demand removal of up to 75%. Moreover, our MIL-100(Fe) catalyst retained this performance for seven cycles of operation, which offers potential applications for metal–organic frameworks as catalysts in wastewater treatment. [ABSTRACT FROM AUTHOR]

Healable polymers with damage healability under external stimuli are attractive materials in many industrial applications. It is also highly desirable to produce materials capable of healing at moderate conditions without sacrificing the mechanical properties when incorporating reversible interactions in a facile and practical way. A straightforward approach is proposed to manufacture networks containing dynamic Diels–Alder and thiourethane bonds and shape recovery ability. Such materials were capable of mild-temperature-triggered healing of scratches, complete cuts and deformation damages. The materials were prepared via chain-end crosslinking of maleimide-telechelic poly(caprolactone-thiourethane) precursors that contain multiple rigid bismaleimide segments. Monitoring the chain length of the precursors led to changes in the network mechanical and healing performance; the best obtained material showed high tensile strength (~ 36 MPa) and Young's modulus (~ 330 MPa) and good healing efficiency at mild temperature (complete healing of scratches and cuts and tensile strength recovery of 87% at 70 °C). [ABSTRACT FROM AUTHOR]

In this paper, two novel donor–acceptor (D-A) and donor-donor (D-D) conjugated polymers containing dithieno[3,2-b:2',3'-d]pyrrole in combined respectively with thieno[3,4-c]pyrrole-4,6-dione and benzo[1,2-b:4,5-b']dithiophene derivatives were synthesized successfully via direct (hetero) arylation polymerization where the Pd(OAc)2 and PCy3.HBF4 have been used as the catalyst system. The obtained conjugated copolymers have been characterized via FT-IR, GPC, 1H NMR and XRD to determine the chemical structures, chemical compositions as well as the macromolecular characteristic features. In addition the conjugated polymers have been investigated for the optical and thermal properties including UV–Vis, fluorescent emission, DSC and TGA respectively. The electrochemical properties of the conjugated polymers have been evaluated via cyclic voltammetry to determine the HOMO–LUMO energy levels which are suitable for organic solar cells devices. [ABSTRACT FROM AUTHOR]

In this research, three organic photocatalysts, 4-(4H-dithieno[3,2-b:2′,3′-d]pyrrol-4-yl)-N,N-diphenylaniline, 4-(pyren-1-yl)-4H-dithieno[3,2-b:2′,3′-d]pyrrole and 4-(6b,10-dihydroperylen-3-yl)-4H-dithieno[3,2-b:2′,3′-d]pyrrole have been successfully synthesized through C-N coupling reactions. The chemical structures and the optical properties of the obtained organic photocatalysts have been characterized via1H NMR, 13C NMR, elemental analysis, and UV-Vis spectroscopy. Next, these dithieno[3,2-b:2′,3′-d]pyrrole-based photocatalysts have been used for the polymerization of methyl methacrylate, 2-(dimethylamino)ethyl methacrylate and tert-butyl methacrylate monomers under 365 nm UV irradiation, resulting in (meth)acrylate polymers with controlled molecular weights and low polydispersity indexes. [ABSTRACT FROM AUTHOR]

The flame‐retardant low‐density polyethylene (LDPE) composites loading aluminum hydroxide (ATH), red phosphorus (RP), and expandable graphite (EG) were successfully prepared. The flame retardancy, the thermo‐oxidative stability, and the mechanical property of the composites were investigated. The synergistic effect of ATH, RP, and EG on the flame‐retardant property and thermal behavior of LDPE were observed. The limiting oxygen index value of LDPE significantly increased from 17.1% to 25.4% upon the incorporation of 15 wt.% of the mixture of three fillers with ATH:RP:EG mass ratio of 1:1:1; and this composite achieved the V‐0 classification of the UL94 vertical burning test. The thermogravimetric analysis of this composite under air atmosphere revealed that its residue weight remained 27.89% at 900°C. Furthermore, the results of tension tests indicated that the surface modification of ATH by magnesium stearate and RP by poly(methylhydrosiloxane) noticeably improved the tensile strength and the elongation of the composite. [ABSTRACT FROM AUTHOR]

Diketopyrrolopyrrole (DPP) is one of the most used moieties in D–A conjugated polymers for high-performance π-extended conjugated polymer-based organic solar cells. The combination of 1,4-diketo-3,6-dithienylpyrrolo[3,4-c]pyrroles (DTDPPs) and the donor moieties 10-(4-((2-ethylhexyl)oxy)phenyl)-10H-phenothiazine (M1), 10-(4-((2-ethylhexyl)oxy)phenyl)-10H-phenoxazine (M2), has not been reported yet. In this report, novel low-bandgap D–A conjugated polymer derivatives including DTDPP, phenothiazine and phenoxazine were successfully synthesized via direct (hetero) arylation polymerization with in the yields of 40.94–60.77%. The obtained D–A conjugated polymers named poly(3,6-Di(2-thienyl)pyrrolo[3,4-c]pyrrole-1,4-dione)-alt-(10-(4-((2-ethylhexyl)oxy) phenyl)-10H-phenothiazine) (P1) and poly(3,6-Di(2-thienyl)pyrrolo[3,4-c]pyrrole-1,4-dione)-alt-(10-(4-((2-ethylhexyl)oxy) phenyl)-10H-phenoxazine) (P2) exhibited a wide range of absorption spectrum in visible light region and have a low bandgaps of 1.4–1.5 eV, as well as thermal stabilities, these D–A conjugated polymers are very promising as activated polymeric materials for organic solar cells (OSCs). [ABSTRACT FROM AUTHOR]

In this study, new donor–acceptor (D–A) conjugated polymers based on 4-(4-((2-ethylhexyl)oxy)phenyl)-4H-dithieno[3,2-b:2′,3′-d]pyrrole (EPDP) and 3,6-bis(5-bromothiophen-2-yl)-2,5-bis(2-ethylhexyl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione (BTBP) or 4,7-bis(5-bromothiophen-2-yl)benzo[c][1,2,5]thiadiazole (BT) have been synthesized successfully via direct (hetero)arylation polymerization using Pd(OAc)2 and PCy3·HBF4 as a catalyst system. The obtained D–A conjugated polymers have been characterized via1H NMR, GPC, FTIR, DSC, XRD, PL and UV-Vis methods. Afterward, the D–A conjugated polymers have been applied for the fabrication of organic solar cells based on bulk-heterojunction (BHJ) structures. [ABSTRACT FROM AUTHOR]

In this research, new donor–acceptor (D‐A) photovoltaic polymers were synthesized from dithieno[3,2‐b:2′,3′‐d]pyrrole electron donor derivatives, including N‐benzoyldithieno[3,2‐b:2′,3′‐d]pyrrole and N‐(4‐hexylbenzoyl)dithieno[3,2‐b:2′,3′‐d]pyrrole, in combination with the electron deficient unit 2,5‐bis(2‐ethylhexyl)‐3,6‐di(thiophen‐2‐yl)‐2,5‐dihydropyrrolo[3,4‐c]pyrrole‐1,4‐dione via direct (hetero)arylation polymerization. The D‐A conjugated polymers obtained were characterized via 1H NMR, gel permeation chromatography, Fourier transform infrared spectroscopy, DSC, XRD, photoluminescence and UV–visible methods. In addition, these D‐A polymers were used as activated layers in bilayer and bulk heterojunction structures for the fabrication of organic photovoltaic cells. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The rigid polyurethane foams (RPUFs) filled with organoclay cloisite 20A and expandable graphite (EG) were prepared by the one-step expanding foam method. Flame behavior, mechanical properties, and thermal conductivity of the composites were investigated. The vertical burning test (UL-94V) and limiting oxygen index (LOI) showed that the flame retardancy was increased proportionally with the content of EG in PU composite. However, the presence of EG filler impaired the thermal insulation and the compressive strength of the composite. In this report, we proved that organoclay could improve the compressive strength, thermal insulation, and flame retardancy of EG/polyurethane composites. This work can contribute to the development of environment-friendly flame-retardant products for green growth. [ABSTRACT FROM AUTHOR]

The photoswitching poly(pyrene-1-ylmethyl-methacrylate-random-methyl methacrylate-random-methacrylate spirooxazine) was synthesized via atom transfer radical polymerization and characterized by proton nuclear magnetic resonance (1H NMR), gel permeation chromatography (GPC), Fourier transform infrared (FTIR) spectroscopy, UV-visible spectroscopy, and differential scanning calorimetry (DSC). The obtained copolymer exhibited the capability of erasable and rewritable photoimaging, making it a potential candidate for optical data storage materials. Moreover, the copolymer also showed the sensing ability for cyanide anions effect in aqueous solutions. [ABSTRACT FROM AUTHOR]

ABSTRACT: A study of the reactions between various furan and maleimide model compounds and the effects of reaction conditions was performed, allowing for a proper design and preparation of a thermo‐reversible polyurethane (PU) material crosslinked via Diels–Alder (DA) bonds. Thus, a linear polyurethane containing furan groups along the main chain was synthesized and crosslinked with a bismaleimide by means of DA reaction. The obtained thermoset exhibited thermo‐reversibility as evidenced by DSC and FTIR microscopy, providing the material recyclability and scratch healability. Optical microscopy, SEM and tensile analysis of a scratched PU film revealed that efficient scratch healing was enabled by heating at 110 °C for 30 min and subsequently keeping at room temperature for 24 h, resulting in an approximately 80% recovery of the pristine mechanical strength. This material is a promising candidate for the development of self‐healing coatings. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 1806–1814 [ABSTRACT FROM AUTHOR]

Thermoresponsive shape memory poly(ε-caprolactone) (PCL) networks with readily tunable properties are prepared exploiting the facile UV-initiated thiol-ene methodology. PCLs with multiple pendant double bonds at both chain ends are used to cross-link with multi-thiol compounds via photo-initiated thiol-ene reactions. Mechanical and shape memory properties can be altered through changes in the number of alkene side groups at the PCL chain termini and thiol cross-linker structure. In parallel with structural investigation by spectroscopic techniques, the relationships between the composition and material properties are investigated. The PCL thermoset materials exhibit excellent thermoresponsive shape memory performance by changing the operation temperature below or above the melting temperature of crystalline PCL segments, which varies in the range of 34-40 °C, and the highest shape retention and recovery ratios can reach 98-100%. [ABSTRACT FROM AUTHOR]

ABSTRACT A simple and facile strategy for the functionalization of commercial poly(ε-caprolactone) diols (PCLs) with pendant functionalities at the polymer chain termini is described. Well-defined allyl-functionalized PCLs with varying numbers of allyl end-block side-groups were synthesized by cationic ring-opening polymerization of allyl glycidyl ether using PCL diols as macroinitiators. Further functionalization of the allyl-functionalized PCLs was realized via the UV-initiated radical addition of a furan-functionalized thiol to the pendant allyl functional groups, showing the suitability for post-modification of the PCL materials. Changes in polymer structure as a result of varying the number of pendant functional units at the PCL chain termini were demonstrated. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 928-939 [ABSTRACT FROM AUTHOR]

Star-shaped molecules consisting of regioregular poly(3-hexylthiophene) ( P3HT) chains as the arms, attached to either a propeller-like triphenylamine or a planar triphenylbenzene core, have been synthesized via Suzuki coupling. The structures of the three-arm star-shaped poly(3-hexylthiophene) (s- P3HT) materials obtained were studied using Fourier transform infrared, 1H and 13C NMR, XRD, gel permeation chromatography and DSC. The s- P3HT polymers were soluble in common organic solvents and exhibited number-average molecular weights of 6000-7200 g mol−1. Their optical properties in solutions and in solid state films were investigated using the UV−visible absorption and photoluminescence techniques, and were compared with those of linear P3HT. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The rod–coil diblock copolymers combining the conductive feature of a conjugated polymer and nanoscale morphologies arising from microphase separation of dissimilar blocks are attractive as potential materials for electronic applications. Herein, we report on the synthesis and properties of a novel diblock copolymer containing a rod-block of regioregular poly(3-hexylthiophene) (P3HT) and poly(methyl methacrylate-random-2-methyl methaspirooxazine) (P3HT-b-P(MMA-r-MSp)) as photo-responsive coil-block. Well-defined rod–coil P3HT-b-P(MMA-r-MSp) diblock copolymers with average molecular weight of around 10,000 and low molar mass dispersities (ÐM) below 1.5 were successfully synthesized via the combination of quasi-living Grignard metathesis polymerization and atom transfer radical polymerization (ATRP). Post-polymerization end-group modifications of the as-obtained P3HT were then successfully realized to give a macroinitiator for the ATRP of MMA and MSp co-monomers, resulting in the P3HT-b-P(MMA-r-MSp) diblock copolymers. The structure and properties of the resulting diblock copolymers were characterized by proton nuclear magnetic resonance (1H NMR), gel permeation chromatography, Fourier transform infrared, UV–visible spectroscopy, and differential scanning calorimetry. [ABSTRACT FROM AUTHOR]

Amphiphilic rod-coil diblock copolymers combining the conductive features of a conjugated polymer and nanoscale morphologies arising from micro-phase separation of dissimilar blocks are attractive as potential materials for electronic applications. The synthesis and properties are reported for a novel amphiphilic diblock copolymer containing a block of regioregular poly(3-hexylthiophene) (P3HT) and poly(methyl methacrylate- random-2-hydroxyethyl methacrylate) (P(MMA- r-HEMA)) as the hydrophilic block. Well-defined rod-coil P3HT- b-P(MMA- r-HEMA) amphiphilic diblock copolymers with molar masses of around 11,000 and low molar mass dispersities ( ĐM) below 1.5 were successfully synthesized via the combination of quasi-living Grignard metathesis (GRIM) polymerization and atom transfer radical polymerization (ATRP). P3HT was first obtained in a regioregular form with an average molecular weight of around 7,200 g/mol and ĐM below 1.3. Post-polymerization end-group modifications of the asobtained P3HT were then successfully realized to give a macroinitiator for the ATRP of MMA and HEMA co-monomers, resulting in the P3HT- b-P(MMA- r-HEMA) diblock copolymers. The structure and properties of the resulting diblock copolymers were characterized by proton nuclear magnetic resonance ( 1H NMR), gel permeation chromatography (GPC), Fourier transform infrared (FTIR) spectroscopy, UV-visible spectroscopy and modulated differential scanning calorimetry (MDSC). [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Novel donor–acceptor (D-A) conjugated polymers containing phenothiazine and diketopyrrolopyrrole derivatives were successfully synthesized via direct arylation polymerization using the palladium catalyst system. The C-N coupling reaction was performed for the synthesis of 4-(10H-phenothiazin-10-yl)-N,N-diphenylaniline (PDA) and 10-(pyren-1-yl)-10H-phenothiazine (PYP) as donor monomers. The D-A conjugated polymers synthesized by polymerization of PDA/PY with diketopyrrolopyrrole have been characterized via GPC, 1H NMR, FTIR, XRD, DSC, PL and UV-Vis spectroscopy, and used for fabrication of organic field effect transistors. [ABSTRACT FROM AUTHOR]