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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]

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]

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]

This paper reports on the synthesis and properties of amphiphilic diblock copolymers composed of a regioregular poly(3-hexylthiophene) (P3HT) block and a block of poly( N,N -dimethylamino-2-ethyl methacrylate- random -2-hydroxyethyl methacrylate) (P(DMAEMA- r- HEMA)). Well-defined rod-coil P3HT- b -P(DMAEMA- r- HEMA)) diblock copolymers were synthesized via the combination of quasi-living Grignard metathesis (GRIM) polymerization, end group modification, atom transfer radical polymerization (ATRP), and post-polymerization modification of diblock copolymer precursors and exhibited an average molecular weight of around 11,000 g/mol with low polydispersities below 1.5. The P3HT- b -P(DMAEMA- r- HEMA)) diblock copolymers were easily converted to amphiphilic diblock copolymers due to esterification of HEMA hydroxyl groups and amine quaternization of DMAEMA units to yield anionic or cationic amphiphilic diblock copolymers, respectively. The structure and properties of the resulting diblock copolymers were characterized by proton nuclear magnetic resonance ( 1 H NMR), gel permeation chromatography, Fourier transform infrared, UV–vis spectroscopy, and differential scanning calorimetry. [ABSTRACT FROM AUTHOR]