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Environment-friendly and robust nanocellulose/metal-organic framework aerogel composites were prepared for effective detoxification of chemical warfare agent simulants both in static and dynamic continuous flow systems. For this, we fabricated a durable porous composite of the UiO-66 catalyst and TEMPO-oxidized cellulose nanofibers (TOCN) to examine as a detoxification filter. Even with over 50 wt % UiO-66, the obtained cellulose aerogel composites exhibited high stability without leaking of UiO-66 for 4 weeks under an aqueous state. The cellulose aerogel composite with 54 wt % UiO-66 showed a quite high surface area (483 m2 g-1) despite the presence of TOCN, which caused fast degradation of methyl paraoxon (MPO), a nerve agent simulant, with a 0.7 min half-life in an aqueous solution with N-ethylmorpholine buffer. This aerogel composite was then examined as the detoxification filter in the continuous flow system under a 7.2 mL h-1 flow rate, which surprisingly decomposed 53.7 g of MPO within 1 h with 1 m2 of the effective area.

Metal organic frameworks (MOFs) have been suggested as promising materials for application in the degradation of chemical warfare agents, with the majority of studies to date focusing on nerve agents. One of the most prominent MOFs used in the detoxification of nerve agents is UiO-66, which is of interest as a future nerve agent decontaminant. However, blister agents, which constitute one of the most toxic and highly reactive categories of chemical agents, are yet to be examined as gas-phase decontamination targets using MOF structures. In this study, a novel type of UiO-66 with a smaller particle size, namely, UiO-66S, was used as a decontaminant for the blister agent simulant, 2-chloroethyl ethyl sulfide (2-CEES). The gas-phase chemical adsorption and decomposition of 2-CEES were demonstrated for the first time, with an estimated t1/2 of 1.34 h. This value is the highest reported value for an MOF in gas-phase reaction conditions. The obtained nontoxic degradation products were identified, and the reaction mechanism was studied using density functional theory calculations. Furthermore, the synthesized UiO-66S catalyst also exhibits superior catalytic ability toward nerve agent simulants (diisopropyl fluorophosphate).The results of the study provide a firm basis for the use of UiO-66S as a future decontaminant for both nerve and blister agents.

An acid-base bifunctional zeolitic imidazolate framework catalyst (ZIF8-A61-SO3H) with amine and sulfonic acid groups was successfully prepared through simple two step post-synthetic modification: preparation of amine-functionalized ZIF-8 with amine contents of 61% (ZIF8-A61) by the ligand exchange of 2-mIM with 3-amino-1,2,4-triazole (Atz), followed by the sulfonic acid functionalization by the ring-opening reaction of 1,3-propanesultone with –NH2 groups in ZIF8-A61. Amine-functionalized ZIF8-A materials with difference amine contents (15%, 34%, and 61%, respectively) were also prepared by controlling the synthesis time. All obtained ZIF catalysts evaluated as a heterogeneous catalyst for one-pot deacetalization-Knoevenagel condensation tandem reaction. Compared with ZIF-8 and amine-functionalized ZIF-8 catalysts, ZIF8-A61-SO3H catalyst showed good catalytic performance with 100% conversion of the reactant and 98% selectivity of the final Knoevenagel product. An enhanced catalytic activity can be attributed to the co-existence of site-isolated acid-base groups on the ZIF8-A61-SO3H catalyst in close proximity. The heterogeneous nature of the catalytic system was confirmed by a hot-filtering test and the catalyst also exhibited reusable in the five repeated cycles. A plausible catalytic mechanism of deacetalization-Knoevenagel condensation reaction over ZIF8-A61-SO3H was also proposed.

A catalytic hydrolysis rate of nerve agents can be a significant issue because of their severe toxicity which can lead to severe damage to human life. Regarding the issue, much effort has been given rise to the development of the various design of Zr(IV)-based MOF catalysts so that high catalytic performance. However, we still have feasibility issues. To this end, we turned our attention to develop the method for facile, scalable, and efficient synthesis of Zr(IV)-based MOFs (UiO-66) with high-performance hydrolysis by imparting enriched active sites to the catalysts, as well as to examine its feasibility using the combination of UiO-66 with the organic bases including 4-ethylmorpholine (4-EM) and linear-/ branch-type polyethyleneimine (PEI). The modulated UiO-66 catalysts were synthesized by varying the total reaction concentration. The synthesized three different UiO-66 catalysts were characterized and then applied for hydrolysis rates of the methylparaoxon (MPO) nerve agent simulant. From these investigations, we found that the highest concentration led to the smallest particle size (ca. 100 nm) and highest defect density (1.8 per cluster), resulting in 3-times higher catalytic activity (0.548 s−1) in turnover frequency (TOF) relative to that of the uncontrolled UiO-66 (ca. 580 nm and 1.6 per cluster) (0.188 s−1) which is prepared by the reported procedure. In addition, the reaction process significantly influenced on the catalytic activity of UiO-66, in which the simple change of the reagent mixing method led to a ca. 182-times difference in the catalytic activity for MPO hydrolysis despite using the same reagents including catalysts and bases. Importantly, we found that the reaction process-dependent catalytic activity of UiO-66 can be significantly associated with the chelation of Zr(IV) Lewis acidic active sites by base materials of 4-EM and PEI (Lewis base). Furthermore, the solid-state catalytic system based on the polymer composite of UiO-66S/LPEI10k on the cotton fabric was also examined for MPO hydrolysis at various relative humidity and temperature conditions to create actual atmosphere conditions, which gave the possibility for actual military applications such as protective suits and equipment. In addition, we schematically demonstrated the loss of active sites on UiO-66 by chelation effects based on experimental and density functional theory (DFT)-derived computational simulation because it is highly correlated to the feasibility of Zr(IV)-based MOF catalysts for detoxification of nerve agents. In addition, we carefully propose a plausible reaction mechanism step on the nucleophilic attack by hydroxide group on the basis of the computational simulation.

Development of new hole-transport layer (HTL) materials for organic photovoltaic (OPV) applications is one crucial issue to mitigate such limitations of low power efficiency, processibility, and stability derived from poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) as a common HTL material. To this end, poly(3-hexylthiophene) (P3HT)-based diblock copolymers including the different ratios between polystyrene (PSty) or/and poly(neopentyl styrene sulfonate) (PNSS) as a second block segment were designed and then used for incorporating with single wall carbon nanotubes (SWCNTs) to form potentially self-dopable nanocomposites. The structure of fabricated P3HT-based diblock copolymer/SWCNT nanocomposites was examined by microscopic and spectroscopic characterizations, exhibiting a charge transfer behavior between P3HT and SWCNT, and growth of the P3HT crystalline phase along the SWCNT surface with a form of the conducting path. The acquired SWCNT nanocomposites exhibited good solubility and dispersion in various organic solvents including toluene, chlorobenzene, THF, chloroform, and DMF, which are good solvents for the PSty or/and PNSS neutral second block. The concept for the neutralized second block by protecting groups can prevent the poisoning ITO substrate by water contamination as shown in the conventional aqueous PEDOT-PSS solution. Notably, the PNSS constituent in the nanocomposite was merely acidified to give in-situ sulfonic acid groups in PSty by simple thermolysis process at 160 °C for 30 min after a solution process for fabrication of a thin film. The thermolysis step provided efficient doping of P3HT by PSS, in which the thiophene groups worked as Bronsted base are protonated by taking protons from sulfonic acid groups and then lead to a form of ionic bonds between cationic thiophene and anionic sulfonate groups. In addition, the formed ionic bonds in the nanocomposites led to an insoluble thin film, which has a good advantage for the further solvent process without substantial damages. The beneficial features of the conducting path along SWCNT and the efficient doping of P3HT by PSS in the acquired nanocomposites led to ca. 5-fold higher electrical conductivity (3.16 S cm−1) and similar work function (5.1 eV) in comparison to water contained commercial PEDOT:PSS (0.6 S cm−1 and 5.0 eV, respectively). As such, the rationally designed potentially self-dopable SWCNT nanocomposites can be one of the promising alternatives beyond the commercial PEDOT: PSS HTL material.

Well-defined methacrylate based amphiphilic block copolymers (BCs) consisting of poly(methyl methacrylate) (PMMA) and poly(ethylene glycol) methacrylate (PPEGMA) were synthesized by atom transfer radical polymerization (ATRP) and used as additives in DMAc casting solution to fabricate poly(vinylidene fluoride) (PVDF) ultra-filtration (UF) membranes in non-solvent induced phase separation (NIPS) process, where the amphiphilic BC additives hydrophilically altered PVDF with PPEGMA block segment by strong interaction with the other PMMA block segment, which reduced water resistance to the PVDF polymer solution during phase separation. FT-IR and XPS studies showed carbonyl groups of BCs in the PVDF membranes, which were not changed even after IPA treatment, indicating that BCs in the membrane were very stable. Obtained PVDF membranes with BCs showed porous surface layer and finger-like pore structures with macrovoids on the sublayers, of which sizes were increased with the increase of BC contents, which were then compared to the pristine PVDF membranes and the PVDF membrane with corresponding other additives such as hydrophobic PMMA, hydrophilic PPEGMA, LiCl and BC/LiCl. Obtained PVDF membranes showed MWCO with 100 K PEO and the best water flux (140 LMH) was achieved in the PVDF membrane with BC/LiCl additive, which was almost 4 times higher than the pristine PVDF membrane. In addition, the PVDF membranes with BC and BC/LiCl additives improved the anti-fouling property for BSA protein, of which reversible fouling resistance ratio was ca. 7 times higher than that of the pristine PVDF membrane.

Various failure modes derived from the electrochemical migration (ECM) through the dielectric polymer layers have been considered critical issues in the electronic devices. Herein, we for the first time suggested the rationally designed epoxy/zeolitic imidazolate framework-8 (ZIF-8) nanocomposite materials for efficient suppression of copper ion migration based on the plausible reaction mechanisms of metal metathesis addressed by sequential cleaving and ligating between metal ions (Zn2+ and Cu2+) and 2-methylimidazole (2-mim) ligands. The fabrication process for epoxy/ZIF-8 (EZ) nanocomposites was first examined to optimize the crosslinking system. The capability of the metal ion capture in the EZ nanocomposites was examined using the aqueous solution containing Cu2+ ions. In addition, the ECM suppression properties were evaluated using the thermal humidity bias (THB) model testing. The representative model investigations with the EZ nanocomposites exhibited substantially enhanced copper ion adsorption and suppression of copper migration in comparison to those of epoxy. Hence, the EZ nanocomposites can be one promising material to alleviate the undesired ECM behavior in electronic device applications.

Two series of water-soluble metalloporphyrin-cored amphiphilic star block copolymers were synthesized by controlled radical polymerizations such as atom transfer radical polymerization (ATRP) and reversible addition fragmentation chain transfer (RAFT), which gave eight amphiphilic block copolymer arm chains consisting of poly(n-butyl acrylate-b-poly(ethylene glycol) methyl ether methacylate) (PnBA-b-PEGMEMA, Mn,GPC = 78,000, Mw/Mn = 1.2, 70 wt% of PPEGMEMA) and poly(styrene-b-2-dimethylamino ethyl acrylate) (PS-b-PDMAEA, Mn,GPC = 83,000, Mw/Mn = 1.2, 67 wt% of PDMAEA), yielding porphyrin(Pd)-(PnBA-b-PPEGMEMA)8 and porphyrin(Pd)-(PS-b-PDMAEA)8, respectively. Obtained metalloporphyrin polymer photocatalysts were homogeneously solubilized in water to apply to the removal of chlorophenols in water, and was distinguished from conventional water-insoluble small molecular metalloporphyrin photocatalysts. Notably, we found that the water-soluble star block copolymers with hydrophobic–hydrophilic core–shell structures more effectively decomposed the chlorophenol, 2,4,6-trichlorophenol (2,4,6-TCP), in water under visible light irradiation (k = 1.39 h−1, t1/2 = 0.5 h) in comparison to the corresponding water-soluble star homopolymer, because the hydrophobic core near the metalloporphyrin effectively captured and decomposed the hydrophobic chlorophenols in water.

To data, combination of Pt-based bimetallic nanocrysatals and the graphene support have significantly contributed to enhance the oxygen reduction reaction (ORR) performance relative to electrocatalysts based on monometallic Pt nanoparticles (NPs) primarily due to the unique ligand effects and benefits of the carbon support. In this study, we propose a new structure of bimetallic electrocatalysts to realize the synergistic effects on the ORR performance through effective integration of the fine-sized Pt NPs, PdPt bimetallic nanocrystals, and non-covalently functionalized graphene with ionic polymers. The facile wet-chemical methods were applied to synthesize fine-sized (2–5 nm) spherical Pt NPs doped large-sized (20–50 nm) non-spherical PdPt bimetallic NPs on the electronically negative ionic polymer-functionalized graphene support (Pt-on-PdPt/fG). This Pt-on-PdPt/fG with synergistic effects based on enlarged active surface area, ligand, and interfacial linking effects, exhibits substantially enhanced ORR activity (specific activity: 1.89 mA c m Pt − 2 at 0.9 VRHE) and durability in comparison to the commercial Pt/C (specific activity: 0.23 mA c m Pt − 2 at 0.9 VRHE). To this end, the effective integration of newly designed fine-sized Pt NPs doped bimetallic nanocrystals and unique graphene supports with the well-interactive ability could be a good platform to develop the advanced electrocatalysts for the efficient ORR.

A series of multi-crosslinkable, self-healing, ladder-structured polysilsesquioxane inorganic-organic hybrid materials were developed to enhance the mechanical properties through tandem UV-curing and Diels-Alder chemistry. The introduction of UV-curable acryl- or epoxy groups allowed for a higher degree of crosslink density while bringing the inorganic backbones closer together for highly efficient self-healing properties, all with a singular material as the ternary organic functional groups consisting of UV-curable function, diene, and dienophile were tethered to the well-defined inorganic backbone. Exceptional thermal stability (>400 °C), optical transparency (>95%), solution processability, as well as robust surface mechanical properties in both bulk (pencil hardness 6H) and nanoscale (elastic modulus > 9 GPa), properties which can be adroitly recovered through mild and rapid thermal treatment hold great promise for next generation hybrid smart coating materials for application in optoelectronic devices.

Heteroleptic ruthenium-complexed ladder-like structured polysilsesquioxane (LPSQ-Ru) was synthesized by post coordination reaction of bidentate ligand side chains in LPSQ with reactive Ru(II) complexes, which was well characterized by 1H and 29Si NMR, FT-IR, and spectroscopic techniques. The photophysical properties of LPSQ-Ru were examined by UV and PL analyses in both solution and solid states, comparing to analogous polymers of ruthenium-complexed polystyrene (PS-Ru). Obtained absorptions of LPSQ-Ru and PS-Ru were broadened ranging from 390-490 nm regardless of the states. However, LPSQ-Ru exhibited higher and shaper PL emission spectrum in comparison to that of PS-Ru, particularly in the solid state, because Ru-complexes in LPSQ were much effectively isolated, preventing their aggregations due to the rigid double strained siloxane backbone. This extinguished photophysical property in LPSQ-Ru kept after intensive thermal treatment at 250 °C for 90 min, which was not achieved in PS-Ru (~5-fold decrease). These differences originated from the backbone structures were also appeared in electrochemical properties in the solid states.

An in-depth examination of the self-healing properties of both dienophile and diene functionalized ladder-like structured polysilsesquioxane copolymers and terpolymers was investigated. Through functionalization of both diene and dienophile on the double-stranded siloxane backbone with ternary n-alkyl functional groups acting as chain mobility control, the effect of chain mobility and chemical structure on self-healing and mechanical properties were elucidated. All of the single component self-healing hybrid materials exhibited fast healing times (∼5 min), and their de-crosslinked adducts exhibited exceptional retention of solubility in common organic solvents for good reusability, all while having inherent high thermal stability and optical transparency.

Porous-structured noble metal electrocatalysts offer activity and durability benefits based on a high surface area and interconnected nanostructure, respectively. However, conventional technical methods used for synthesizing a porous structure are still difficult as well as resulting in defects in the structure. Here we report a facile route for the synthesis of uniform, large-area mesoporous platinum thin films based on ionic polymer doped graphene, which exhibit substantially enhanced activity and durability for oxygen reduction relative to commercial Pt/C. Notably, a remarkable durability (≥95% retention of electrochemical activities after 30 000 cycles of intensive accelerated durability tests) is acquired which is ascribed to the synergistic effects derived from the interconnected Pt structure (morphology) and ionic polymer-doped graphene (support). The suggested robust concept for a controlled mesoporous-structured platinum thin film on graphene could be a great breakthrough for obtaining a highly durable electrocatalyst.

Palladium nanoparticles on ionic polymer-doped graphene (Pd–IPG) nanocomposite catalysts have been investigated for efficient Suzuki coupling reactions. This combination effected highly accelerated Suzuki coupling reactions due to several advantageous features associated with the flanking ionic polymer part of the catalyst system. These include a high level of Pd incorporation, excellent dispersion stability, and increased accessibility and diffusion of the substrates onto the surface of Pd NPs. The enhanced availability of the Pd catalyst to the reacting substrates is believed to allow for ca. 16-fold higher catalytic activity than that of Pd–graphene without the ionic polymer. Moreover, high recycling capability of the catalyst (10 times) in combination with excellent product yields (>96%) and no significant leaching of the catalyst upon hot-filtration test suggest that the Pd–IPG nanocomposite catalysts have high reusability with significant retention (>95%) of the Pd species.

An investigation into the hydrolysis kinetics of an aqueous base-catalyzed sol-gel reaction yielding ladder-like polysilsesquioxanes was studied using NMR. Under various variables of monomer concentration, water concentration, solvent type, and monomer type, the various effects on molecular weight and degree of condensation were elucidated. Moreover, the various rate orders and rate constants were calculated and compared with previous reports of the hydrolysis of organosilane precursors. Through this study we were able to ascertain the optimal conditions of hydrolysis-polycondensation for obtaining highly condensed, high molecular weight ladder-like polysilsesquioxanes.

The incorporation of pyrene-functionalized poly(methyl methacrylate)-b-poly(dimethylaminoethyl methacrylate) (PMMA-b-PDMAEMA) ionic block copolymer-wrapped carbon nanotubes (PBCNTs) with graphene oxide (GO) allows compact decoration of metal nanoparticles (NP) for use as robust catalysts. This well-tailored concept of the PBCNT-GO functional carbon support provides various features, including a two-dimensional (2D) structure, dimensional stability, versatile solubility (from toluene to water), enhanced diffusion of reagents, and recyclability. Among the various compositions of GO and PBCNT, 50 wt% of the PBCNT additive-containing support (PBCGO55) showed great hybridization potential for Ag, Au, and Pd NPs. In particular, the hybridization of PBCGO55 with Pd NPs (Pd-PBCGO55) displayed superior morphological features with compact decoration of ultra-fine NPs (1–3 nm), larger surface area, higher density of edge and corner atoms, better dispersion stability, and lesser aggregation of the decorated Pd NPs in comparison with the other hybrid catalysts. In the catalytic reduction of 4-nitrophenol (4-NP), the Pd-PBCGO55 hybrid catalyst exhibited the best catalytic performance, resulting in highly enhanced reaction rate constant (k) of 9.73 min−1 and catalytic activity of 141.8 mol mol−1 min−1, exhibiting a 50-fold increased rate constant and 30-fold increased catalytic activity in comparison to Ag-GO without PBCNT (k = 0.19 min−1, catalytic activity = 4.58 mol mol−1 min−1).

We present a new strategy to strongly and effectively immobilize silver nanoparticles (AgNPs) on polyamide thin film composite membranes to endow antibacterial activity. This method relies on the immobilization of relatively large silica particles (SiO 2 , ~400 nm in diameter), where AgNPs of ~30 nm in diameter are tightly and densely bound (AgNP@SiO 2 ), on the membrane surface using cysteamine as a covalent linker. The formation of multiple Ag–S chemical bonds between a “bumpy” AgNP@SiO 2 and the rough membrane surface provides a great leaching stability of AgNPs and AgNP@SiO 2 . AgNP@SiO 2 particles were well distributed over the entire membrane surface without severe aggregation. The surface coverage of the membrane by AgNP@SiO 2 was tuned by adjusting the deposition time and AgNP@SiO 2 particle concentration. The AgNP@SiO 2 -immobilized membrane showed excellent antibacterial properties against Escherichia coli , Pseudomonas aeruginosa and Staphylococcus aureus, even with a relatively low particle coverage. Importantly, the separation performance (water flux and salt rejection) of the membrane was not impaired by particle immobilization. These beneficial effects are attributed mainly to the sparse and good distribution of AgNP@SiO 2 , which can reinforce the antibacterial activity of AgNPs while having a negligible impact on the hydraulic resistance.

Well-defined multi-armed P3HT star polymers with a gold nanoparticle (NP) core were synthesized by an arm-first method based on a ligand exchange reaction between linear end-functionalized P3HT (P3HT-SH) and gold NPs. A high loading amount of gold NPs to P3HT-SH with a relatively lower molecular weight gave a higher yield of star polymers (∼70%) with a high molecular weight (Mw = 2867k, PDI = 2.1), and the number of P3HT arm chains on one gold NP was 119. The P3HT star polymer with a gold NP core was well-dispersed both in solution and in solid, which was interestingly not crystalline because of the unique 3-dimenstional structure. In addition, surface plasmon resonance (SPR) absorption from the gold NP, as the core of the star polymer, was more enhanced both in solution and in solid, in comparison to those with non end-functionalized P3HT arm chains (P3HT-allyl); however, PL emission was more diminished because of the molecularly contacted P3HT arm chain and gold NP core. This was then introduced in an active layer consisting of P3HT:PCBM in an organic solar cell to increase optical absorption by the SPR effect from the gold NP, however, the device efficiency was rather decreased compared to that of the reference device without gold NPs, which was probably due to direct electron transfer between the gold NP and P3HT.

Poly(vinylidenefluoride-co-trifluoroethylene) (PVDF-TrFE)/SWCNT nanocomposites with ultra-low percolation threshold were prepared by interfacial control using a block copolymer comapatibilizer. For this, a well-defined block copolymer of poly(3-hexylthiophene) (P3HT) and poly(methyl methacrylate) (PMMA) (P3HT-b-PMMA) was synthesized by combination of GRIM and ATRP (Mn = 24 K, Mw/Mn = 1.25), where the P3HT block segment wrapped the SWCNTs by π–π interaction and the resulting PMMA block segment dangled from the SWCNTs, which gave de-bundled SWCNTs without any aggregations for over 5 months in most common organic solvents for PMMA. The block copolymer coated SWCNT (TMCNT) was then mixed with PVDF-TrFE to prepare PVDF-TrFE/SWCNT nanocomposites (PVT-TMCNT), which enabled excellent dispersion of SWCNT in a PVDF-TrFE matrix without aggregation due to the miscibility of the PMMA on TMCNT and PVDF-TrFE. Obtained PVT-TMCNT showed large enhancements of the electrical conductivity and the dielectric constant with ultra-low percolation threshold (fc = 0.07 wt.%) due to excellent interfacial control by the block copolymer comapatibilizer between SWCNT and PVDF-TrFE. Improved ferroelectric properties of PVT-TMCNT were also observed by an increase of field-induced polarization response, which was almost over 10-times higher than for neat PVDF-TrFE.

Compatible hybrid composites (PVLPMA) comprising of poly(vinylidene fluoride) (PVDF) and UV-curable ladder-like polysilsesquioxane (LPMASQ) were investigated for maximizing synergetic effects in various properties. The PVDF fluoropolymer was found to be well-incorporated with the LPMASQ inorganic filler because of good hydrogen-bonding, and the compatibility rigorously investigated by FT-IR, DSC, and WAXS studies. In addition, the crosslinkable function arising from the methacryl-group of the LPMASQ inorganic filler with the aid of the radical source was evaluated from the analysis of various properties. After UV-crosslinking, PVLPMA hybrid composites showcased enhanced mechanical properties such as elastic modulus, surface modulus, and surface hardness with accordance to the increasing the LPMASQ quantity. In addition, hydrophobicity was observed through the increase in the water contact angle up to 115°, a value much larger than that of neat PVDF and cured LPMASQ. Furthermore, the enhanced electrical stability of PVLPMA hybrid composites was obtained through examination of dielectric properties and breakdown strength in comparison to neat PVDF. These PVDF-LPMASQ organic-inorganic compatible hybrid composites with enhanced properties arising from the good compatibility and synergetic effects can be applicable in the various fields supplanting neat PVDF.

Through fine-tuning of the myriad of reaction conditions for an aqueous base-catalyzed hydrolysis–polycondensation reaction, a facile synthesis of structurally controlled polyphenylsilsesquioxanes was developed. Mechanism and kinetic studies indicated that the condensation reaction proceeded through a T1 structured dimer, which was quantitatively and in situ formed through mild hydrolysis of a phenyltrimethoxysilane (PTMS) monomer, to give either the cage-structured polyhedral oligomeric silsesquioxanes (POSS) or the corresponding ladderlike silsesquioxane (LPSQ) with excellent yields. Ladderlike and POSS materials were selectively achieved at higher and lower initial concentrations of PTMS, respectively, and an in-depth spectroscopic analysis of both compounds clearly revealed their structural differences with different molecular weights.

A series of thiol-ene UV-curable inorganic–organic hybrid polysilsesquioxanes of various phenyl:methacryloxypropyl and phenyl:mercaptopropyl copolymer compositions were synthesized in one-batch using a base-catalyzed system. These thermoplastic photocurable ladder-like structured materials were examined as scratch-resistant, hard-coating materials on both glass and PET substrates. The unique fully condensed structure of the hybrid polymers allowed for simplified processing and through variation of the organic functional group, films with high transparency, tunable refractive indices in the range of 1.467–1.546, pencil hardness values of 9H, and high nanoindentation modulus were obtained (7 GPa). These scratch-resistant polysilsesquioxanes may provide insight into the different organic functional group compositions which allow for optimal mechanical properties.

Polysilsesquioxanes (PSSQs) are composite materials consisting of inorganic framework and organic functional groups. Their inherent dual characteristics offer various applications including microelectronics, optics and biosciences. For the first time, free standing ladder-like PSSQ films were successfully prepared for gas separations, allowing practical applications in the membrane area. In order to fabricate a free-standing PSSQ film, a novel ladder-like poly(phenyl-co-glycidoxypropyl) silsesquioxanes with phenyl:glycidoxypropyl copolymer ratio of 6:4 (LPG64) were synthesized by a base-catalyzed sol–gel reaction. Moreover, the LPG64 films were thermally crosslinked with octa(aminophenyl)-T8-silsesquioxane (OAPS) with different concentrations of OAPS. Single gas (i.e. He, H2, CO2, O2, N2, and CH4) transport measurements were performed for the LPG64 as well as LPG64/OAPS composite membranes. The LPG64 membrane exhibited a relatively high CO2 permeability of 47.88 Barrer compared to other gases with CO2/N2 permselectivity of 30.5. The annealing effect on the transport results of the LPG64 membrane was negligible due to its rigid inorganic framework. Combination of our transport analysis and XRD characterization demonstrated that the addition of OAPS led to more dense chain packing, reducing permeability for all the gases tested in this work with increase in permselectivities. Especially, the LPG64/OAPS (80/20 wt/wt) membrane improved He/N2 and H2/N2 permselectivities by 98% and 80%, respectively, compared to those for neat LPG64 membranes.

A series of organic–inorganic hybrid spin-on-glass polymethylsilsesquioxanes were synthesized utilizing a cyclic siloxane precursor, 1,3,5,7-tetramethyl-1,3,5,7-tetrahydroxyl cyclosiloxane (MT4-OH), copolymerized with methyltriethoxysilane (MTES) at various comonomer ratios. By selectively introducing this 2-D cyclic crosslinker, we were able to obtain spin-on-glass hybrimers with low dielectric constant (2.5–2.7), high nanoindentation modulus (5–10.5 GPa), with high thermal stability (>700 °C) without the use of porogens or additives. The use of the cyclic monomer MT4-OH greatly increased the mechanical properties, which allowed for impeccable reliability of a variety of patterns obtained through etching and chemical mechanical planarization processes, while maintaining optimal gap-filling properties. Due to the superior dielectric, mechanical, and integrated processing of these materials, these hybrids derived from MT4-OH may be utilized as next generation spin-on-glass low-dielectric constant materials.

We synthesized an ultra-fine Pd nanocatalyst supported by ionic block copolymer doped reduced graphene oxide (Pd-PIBrGO) for ultra-accelerated nanocatalysis. This hybrid catalyst exhibited exceptionally advanced catalytic performance for the reduction of methylene blue using miniscule quantities of Pd-PIBrGO due to facilitated diffusion of reagents, resulting in full reduction within a few seconds and showing a 280-fold increase of the rate constant over Pd-rGO without ionic block copolymers.

Poly(methyl)silsesquioxane-based spin-on-glass resins incorporating both a cyclic precursor, 1,3,5,7-tetramethyl 1,3,5,7-tetrahydroxyl cyclosiloxane, and incompletely condensed methyl-substituted POSS were synthesized and their thermal, mechanical, and electrical properties were investigated as a function of the POSS loading content. By introducing incompletely condensed methyl-substituted POSS compounds at the molecular level as sol–gel precursors, exceptional thermal stability (>700 °C), good mechanical properties (elastic modulus >4.0 GPa), and an ultra-low dielectric constant (k = 1.8) were obtained. In addition to providing a new route towards fully poly(methyl)silsesquioxane-based spin-on-glass resins with the above properties, the realization of the application of integration circuits was evaluated to show that the ultra low-k, mechanically robust spin-on-glass materials were able to withstand harsh wet chemical and dry etching, as well as chemical mechanical planarization (CMP) processing.

A series of azido-functionalized ladder-like structures was prepared by direct azidation of ladder-like structured poly(p-chloromethylphenyl)silsesquioxane (LPCMPSQ) and poly(chloropropyl)silsesquioxane (LPAPSQ) in excellent yields with perfect substitution of the chloro-compounds. The azido-functionalized silsesquioxanes obtained were then photocured without additional photoinitiator to give highly cross-linked thin films with an exceptionally high modulus (> 12 GPa). Furthermore, these materials were shown to be patterned through photolithography to give impeccable micropatterned microstructures.

Carbon nanotubes (CNTs) coated by compatibilizer (P3HT-PMMA) imparted sta-ble dispersion in organic solvents and polymer matrix (P(VDF-TrFE)). The compatibility be-tween CNTs with P3HT-PMMA was con rmed by measuring Raman spectroscopy. CoatedCNTs were then blended with P(VDF-TrFE) (70:30 mol%) to obtain polymer nanocompositesby solution- casting process. Polymer nanocomposites showed enhanced electrical characteris-tics, as nanocomposites near the threshold of the transition between P(VDF-TrFE) insulatorand CNT conductor revealed great improvement of electrical conductivity up to 10-6 S/cmat 1 KHz. Electromechanical properties of the polymer nanocomposite were examined as afunction of electric eld.

A series of epoxy-functionalized inorganic–organic hybrid ladder-like structured polysilsesquioxanes were synthesized in one-batch via a base-catalyzed co-solvent system. Two types of epoxy functionalities were examined: aliphatic and cycloaliphatic. Obtained polymeric epoxy-functionalized ladder-like polysilsesquioxanes were cationically photopolymerized under UV irradiation over glass and plastic substrates. Obtained cross-linked films were examined as hardcoating materials as their thermal, optical, mechanical, and barrier properties were studied. These materials showed superior thermal properties (Td > 400 °C), high optical transparency (>95%), high pencil hardness (4H–9H), low dielectric constant (3.0–3.6), and good barrier properties (WVTR < 101 g m−2 day−1, OTR < 102 g m−2 day−1).

The first demonstration of polymer nanowire (PNW) crystals based on a diketopyrrolopyrrole-based copolymer (i.e., PDTTDPP), and their application to field-effect transistors (FETs) is reported. Remarkably, transmission electron microscopy and selected area electron diffraction analyses of the PNW reveal its single-crystalline (SC) nature. FETs fabricated of a SC PNW exhibit a maximal charge carrier mobility of ≈7.00 cm(2) V(-1) s(-1) , which is almost one order of magnitude higher than that of the thin-film transistors made of the same polymer (PDTTDPP).

A series of ABA triblock copolymers of methyl methacrylate (MMA) and dodecyl methacrylate (DMA) [poly(MMA-b-DMA-b-MMA)] (PMDM) were synthesized by Ru-based sequential living radical polymerization. For this, DMA was first polymerized from a difunctional initiator, ethane-1,2-diyl bis(2-chloro-2-phenylacetate) with combination of RuCl2(PPh3)3 catalyst and nBu3N additive in toluene at 80 °C. As the conversion of DMA reached over about 90%, MMA was directly added into the reaction solution to give PMDM with controlled molecular weight (Mw/Mn ≤ 1.2). These triblock copolymers showed well-organized morphologies such as body centered cubic, hexagonal cylinder, and lamella structures both in bulk and in thin film by self-assembly phenomenon with different poly(methyl methacrylate) (PMMA) weight fractions. Obtained PMDMs with 20–40 wt % of the PMMA segments showed excellent electroactive actuation behaviors at relatively low voltages, which was much superior compared to conventional styrene-ethylene-butylene-styrene triblock copolymer systems due to its higher polarity derived from the methacrylate backbone and lower modulus. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013

A new photocurable ladder-like poly(phenyl-co-mercaptopropyl)silsesquioxane (LPPMPSQ) was synthesized in one pot via base catalyzed hydrolysis-polycondensation of a comonomer mixture of phenyltrimethoxysilane and 3-mercaptopropyltrimethoxysilane. Obtained LPPMPSQ was characterized by 1H NMR, FT-IR, 29Si NMR, TGA, and the electrical (k = 3.6) and mechanical properties (surface modulus = 4.9 GPa) found to be suitable for application as a photocurable gate dielectric material.

A novel organic-inorganic hybrid-type ladder-like poly(benzylazide) silsesquioxane (LPBAzSQ) and ladder-like poly(propylazide) silsesquioxane (LPPAzSQ) were synthesized through azidation of ladder-like poly(p-chloromethyl)phenylsilsesquioxane (LPCMPSQ) and ladder-like poly(propylchloro)silsesquioxane (LPPCSQ). The ladder-like structure of the synthesized LPBAzSQ and LPPAzSQ compounds, full substitution of azide groups, and their click chemistry with various functional groups was characterized by 1H NMR, 13C NMR, 29Si NMR, FT-IR, GPC. This new approach for functionalization of ladder-like silsesquioxanes has allowed for insertion of polar functional groups that have yet be examined in silsesquioxane chemistry.