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Cisplatin (CDDP) is a potent first-line antitumor drug but suffers severe side effects and poor pharmacokinetics. Its complexation with polycarboxylic acids, such as polyglutamic acids, is generally used to fabricate nanoformulations for CDDP delivery; however, the multiple strong complexations makes intracellular drug release slow. Herein, we report a novel polyphenol-metal coordination method to fabricate CDDP-incorporated core-shell nanoparticles, which are stable in blood circulation but dissociate in the tumor. Methoxyl-PEG terminated with one or two gallic acids (PEG-GA or PEG-GA2) complexed CDDP and produced well-defined nanoparticles (PEG-GAx/Pt) with CDDP loading contents as high as 17.7% to 29.8%. The PEG-GAx/Pt nanoparticles were very stable in the physiological conditions and had slow blood clearance and efficient tumor accumulation, but dissociated quickly and released CDDP in response to the tumor acidity or elevated levels of reactive oxygen species (ROS). PEG-GAx/Pt nanoparticles exhibited improved antitumor efficiency against 4 T1 breast cancer and A549 lung carcinoma with much-reduced toxicity compared to free CDDP. The work demonstrates a new strategy of cisplatin-polyphenol coordination for developing platinum drugs' nanomedicines. Unlabelled Image [ABSTRACT FROM AUTHOR]

Fluorinated block copolymers, hexafluorobutyl methacrylate-block-poly(glycidyl methacrylate) (HFBMA- b -PGMAs, FPGs) were synthesized by atom transfer radical polymerization (ATRP) and applied to fabricating hydrophobic cotton fabrics. Since the HFBMA block provided low surface free energy and the PGMA blocks served as anchors with cotton fibers, the FPGs modified cotton fabrics showed excellent water repellency. The results indicated that nano- and microscale rough structures were created with combining HFBMA blocks onto surfaces of micro-sized cotton fibers. Since the HFBMA blocks were chemically bound to the cotton fibers by epoxy groups of PGMA blocks, the modified cotton fabrics possessed long-term high stability and durability. Furthermore, the important cotton fabric parameters such as tensile strength, color, and haptics were all unaffected by the FPGs modification, which revealed potential for applications. [ABSTRACT FROM AUTHOR]

A series of UV-curable oligomers based on bisphenol-F epoxy resin were synthesized via end-capping of acrylic acid (AA) and 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) in different ratios. Along with the increase of AMPS content, viscosities of modified resins reduced obviously. Integrated performance of cured films was also evaluated. Water swelling and contact angle tests indicated that the hydrophilicity was enhanced by the incorporation of sulfonate and amide groups into the coatings. Thermal degradation behaviors showed that the char residue, as well the glass transition temperature of the cured films was increased with the rising AMPS proportion, though the initial decomposition temperature declined. Moreover, doping of plentiful AMPS caused a remarkable enhancement in elongation at break, which was ascribed to greater flexibility of polymer chains and reduced density of crosslinking structure. Cured films with AMPS modified showed strong adhesive strength resulted from strong hydrogen bonding formed between amide sulfonate groups from AMPS and polar surface of glass substrates. For pure AA modified film, it was unaffected in NaOH solution (2 wt%) for 24 h. While for AMPS modified film, the film could be completely removed in several minutes when exposed to alkali solution. The modified epoxy films with these attractive features had prospective applications in temporary protective coatings, which could resist acid and organic solvents while would be easily wiped off from the substrate by soaking in the alkali solution. [ABSTRACT FROM AUTHOR]

Star polymers (CD-POEGMAs and CD-PNIPAMs), and pseudo-graft polymer (PADMA-(CD-POEGMAs) x ) formed from PADMA with adamantyl(Ad) pendants and CD-POEGMAs by host–guest inclusion complexation were prepared and characterized. This work compared the thermoresponsive and self-assembly mechanisms of the POEGMAs as branches to that of PNIPAMs branched cyclodextrin cored star polymers. In contrast to CD-PNIPAMs which behaved abrupt and intensive dehydration process near its LCST, CD-POEGMAs exhibited thermally induced aggregation process with consecutive conformation changes during the temperature increase process, and gradually self-assembled into cyclodextrin centered aggregates with hydrophobic methacrylate backbone and dehydrated POEGMAs side chains. Moreover, this work provided a supramolecular method controlling and adjusting the thermoresponsive properties of pseudo-graft PADMA-(CD-POEGMAs) x formed from CD-POEGMAs and PADMA via inclusion complexation, which underwent a reversible thermally induced transition from micelle to nano-aggregates. Pseudo-graft PADMA-(CD-POEGMAs) x behaved gradually conformation changes as temperature rising, and self-assembled into aggregates with hydrophobic methacrylate backbone, residual Ads, and dehydrated POEGMAs side chains. [ABSTRACT FROM AUTHOR]

Highlights: [•] MA and SMAS were introduced into the TPEG-type PCEs to improve the dispersion and flow retention abilities. [•] This paper discussed the dispersion and adsorption effects of TPEG-type PCEs compared with conventional MPEG-type PCEs. [•] PCE2 has excellent water-reducing and flow-retaining abilities, which is attributed to the synergistic effects of steric hindrance and electrostatic repulsive force. [•] Application results showed that PCE2 can be used as high-range water reducer in practical applications. [Copyright &y& Elsevier]

Highlights: [•] The synthetic processes of β-cyclodextrin (CD) based functional monomers were improved and characterized in detail. [•] Based on the monovinyl CD based monomer, a new copolymer (PCDs) bearing CD pendants was synthesized and used as superplasticizer. [•] PCDs behaved excellent dispersion ability and strong retarding effect. [ABSTRACT FROM AUTHOR]

Highlights: [•] Diethanolamine modified lignin (DML) has been synthesized and firstly used for the production of Portland cement. [•] DML is effective in the improvement of grindability and particle size distribution, and mechanical properties of the produced cements. [•] In contrast to lignin, both the initial and final setting times of tested cements with DML increased obviously. [Copyright &y& Elsevier]

Abstract: Comb-like polycarboxylate copolymers (PCs) were synthesized and first used as the dispersants for kaolin suspensions. The apparent viscosity, adsorption behavior, zeta potential, rheological behavior, and TEM images of concentrated kaolin slurries deflocculated with these copolymers were systematically investigated. Sodium acrylate homopolymer (SA) was selected as a reference in order to contribute to the knowledge of how the electrostatic interaction and molecular structure of these copolymers influenced the dispersion, adsorption, and rheological properties of colloidal kaolin suspensions. The results showed that the dispersion of kaolin slurries mainly depended on the synergistic effects of electrostatic interaction and steric hindrance for APEG type comb-like copolymers. PC2 bearing proper carboxylic groups and side chains produced stable dispersion and fluidity in concentrated kaolin slurries. Based on the electrostatic and steric effect of comb-like copolymers, the kaolin slurries displayed a shear thickening behavior, and the Herschel–Bulkley model well described their rheological behaviors. [Copyright &y& Elsevier]

The flexural strength and compressive strength are the two most important parameters that characterize the mechanical properties of cement-based materials, but the two are usually mutually exclusive or negatively correlated. The flexural strength of cement-based materials cannot be effectively improved by a single nanomaterial without reducing their compressive properties. Therefore, compounding various micro–nano materials, fully utilizing their respective advantages, and developing composite materials with new properties and application characteristics are important techniques for enhancing the mechanical properties of cement-based materials. This study aimed to investigate the synergistic enhancement of the mechanical properties of concrete by using microcrystalline cellulose (MCC) and nano-silica (NS) composites. MCC and NS were mixed and modified to synthesize MCCNS materials, which were added to cement slurry for experiments. Results indicated that the flexural strength and compressive strength of the cement paste with MCCNS materials were significantly increased compared with those of the cement pastes without MCCNS or with only NS. The flexural strength of the cement paste with MCCNS-1 was increased by 47%, 20%, 6.3%, and 6.8% after curing for 1, 7, 28, and 56 days, respectively. Meanwhile, compressive strength was also increased by 14.4%, 6.3%, 6.8% and 6.5%, respectively. In addition, the reaction mechanism was speculated through a variety of test results. The addition of MCCNS material facilitated the formation of additional C-S-H, which also contributed to enhancing the mechanical properties of cement paste. • Novel nanocomposites were synthesized using MCC and NS through adsorption-phase reaction and sol–gel methods. • The mechanical properties of cement-based materials were notably enhanced by incorporating MCCNS materials. • The volcanic ash activity of NS led to additional C-S-H formation, improving the mechanical strength of the cement paste. [ABSTRACT FROM AUTHOR]

Pt nanoparticles supported on MgAl-hydrotalcite catalyst was prepared via impregnation-reduction method followed by an in situ rehydration process, which showed excellent catalytic performance towards aerobic oxidation of glycerol to glyceric acid. Glycerol (GLY) aerobic oxidation in an aqueous solution is one of the most prospective pathways in biomass transformation, where the supported catalysts based on noble metals (mainly Au, Pd, Pt) are most commonly employed. Herein, Pt nanoparticles supported on rehydrated Mg x Al 1 -hydrotalcite (denoted as re-Mg x Al 1 -LDH-Pt) were prepared via impregnation-reduction method followed by an in situ rehydration process, which showed high activity and selectivity towards GLY oxidation to produce glyceric acid (GLYA) at room temperature. The metal-support interfacial structure and catalyst basicity were modulated by changing the Mg/Al molar ratio of the hydrotalcite precursor, and the optimal performance was achieved on re-Mg 6 Al 1 -LDH-Pt with a GLY conversion of 87.6% and a GLYA yield of 58.6%, which exceeded the traditional activated carbon and oxide supports. A combinative study on structural characterizations (XANES, CO-FTIR spectra, and benzoic acid titration) proves that a higher Mg/Al molar ratio promotes the formation of positively charged Pt δ+ species at metal-support interface, which accelerates bond cleavage of α-C–H and improves catalytic activity. Moreover, a higher Mg/Al molar ratio provides a stronger basicity of support that contributes to the oxidation of terminal-hydroxyl and thus enhances the selectivity of GLYA. This catalyst with tunable metal-support interaction shows prospective applications toward transformation of biomass-based polyols. [ABSTRACT FROM AUTHOR]

• Novel organic/inorganic nanocomposites LNTS-1 and CNTS-2 were synthesized from NS and alpha thioctic acid. • Compared with bulk CNTS-2, linear LNTS-1 can effectively improve the macro flexural strength of cement-based materials. • The results of adsorption experiments show that LNTS-1 has strong adsorption on calcium ions. Using organic/inorganic nanocomposites to optimize the microstructures of cement hydration products at the micro/nanometre scale is a promising method for improving the mechanical properties of cement-based materials. One type of novel nanohybrid material modified by the flexible autonomous healing polymer poly-TA (thioctic acid) was synthesized and used as a highly efficient mechanical improvement agent for cement paste. The nanohybrids linear LNTS-1 and bulk CNTS-2 were synthesized from silane-coupled nanosilica and alpha thioctic acid. Due to the existence of hydrogen bonds, coordination bonds and dynamic covalent S S bonds, this type of linear poly-TA with a certain amount of calcium content exhibited good self-healing properties. Linear LNTS-1 can effectively improve the macro flexural strength of cement-based materials without a negative effect on their compressive strength. The flexural strength of cement pastes with 1.0‰ LNTS-1 increased by 11.9%, 15.6%, and 16.9% after curing for 3, 7, and 28 d compared with the control cement paste. The results of adsorption experiments show that nanohybrid LNTS-1 has strong adsorption on calcium ions, which affects the formation of cement hydration products. [ABSTRACT FROM AUTHOR]

A ternary system thermoresponsive hydrogel, poly( N -isopropylacrylamide- co -hydroxyethyl methylacrylate polycaprolactone)/hydroxypropyl cellulose (or P(NIPAAm- co -HEMAPCL)/HPC), was prepared via “alkynyl/azide” click chemistry between the azide modified graft copolymer P(NIPAAm- co -HEMAPCL-N 3 ) and the alkynyl modified HPC (or alkynyl-HPC). The structures of P(NIPAAm- co -HEMAPCL-N 3 ) and alkynyl-HPC were characterized by 1 H NMR, SEC and FT-IR, and the results demonstrated that the mole ratio of the alkynyl and azide functional groups, and the feed ratios of HPC, PCL, and PNIPAAm could be easily adjusted. The incorporation of PCL and HPC dramatically enhanced the compression modulus of the P(NIPAAm- co -HEMAPCL)/HPC hydrogel, which ranged from 500 to 1000 g/cm 2 . Due to the immiscibility of HPC and PCL, a heterogeneous and semicontinuous structure was observed via SEM. The incorporation of HPC accelerated the water absorption rate and enhanced the hydrogel's ability to shed water. The swelling–deswelling and compressive properties could also be adjusted by changing the feeding ratio. The hydrogel exhibited reversible swelling–deswelling behavior after three “swelling–deswelling” cycles. [ABSTRACT FROM AUTHOR]

Poly(amino acid)-type macromolecules (PAAs), poly(ethylene glycol) -b- poly(aspartic acid) (PEG-PAAs), and poly(ethylene glycol)- b -poly(glutamic acid) (PEG-PGAs) were synthesized, and their states in aqueous solutions were studied. PEG-PAAs and PEG-PGAs were first used as novel polycarboxylate superplasticizers, and their dispersion and adsorption behaviors were investigated in cement slurries in the absence and presence of montmorillonite (MMT) clay. The results demonstrated that both PEG-PAAs and PEG-PGAs not only showed excellent water reducing and fluidity retention capabilities but also exhibited remarkable MMT clay tolerance. In contrast to the stretched molecular conformation of traditional polycarboxylate superplasticizers (PCEs), the hydrophobic main chain and the side methylene and ethylene linkers connected to the carboxylic groups of PAA and PGA segments resulted in self-assembly of the PEG-PAAs and PEG-PGAs in aqueous solutions, and the self-assembled nanosized aggregates exhibited relatively uniform spherical morphologies with average sizes of 30–100 nm. Carboxylic groups located on the periphery of the nanoaggregates acted as anchors and adsorbed on the surfaces of the cement particles. The nanoaggregates and the stretched hydrophilic PEG side chains, which jointly produced and enhanced the steric hindrance to prevent cement particle aggregation and hydration, resulted in notable dispersion capabilities. Total organic carbon (TOC), X-ray diffraction (XRD), and thermogravimetry–differential scanning calorimetry (TG-DSC) analyses revealed that the adsorption between the MMT clay and PAA nanoaggregates was surface adsorption (rather than interlayer adsorption), and this significant finding could be ascribed to the enlarged steric hindrance of the PAA nanoaggregates, which prevented the interlamination adsorption consumption of MMT clay to PAAs and revealed the outstanding clay insensitivity. This study provides a new perspective and strategy to design novel poly(amino acid)-type superplasticizers (PAAs) with excellent dispersion performances and improved clay tolerance. [Display omitted] • Poly(amino acid)-type superplasticizers (PAAs) with enhanced dispersing performance for cement doped with clay impurities. • The self-assembled nanoaggregates of PAAs enhanced steric hindrance and resulted in notable dispersion capabilities. • The enlarged steric hindrance of PAAs prevented interlamination adsorption and revealed outstanding clay insensitivity. [ABSTRACT FROM AUTHOR]

Abstract: A novel Eu-complex Eu(TTA)2vinyl-phen has been designed and synthesized via simple reaction as an efficient fluorescent sensor for F−, CH3COO−, and H2PO4 −. The anion-sensitivity of Eu-complex was evaluated using a series of anion in DMSO solution. On binding with F−, CH3COO−, or H2PO4 −, fluorescence quenching of Eu-complex was easily observed, while no obvious fluorescence change could be observed in the presence of other anions. More importantly, the Eu-complex exhibited excellent selectivity and sensitivity for F− and H2PO4 − in water/DMSO (5/5) solution. The titration results of UV–vis, fluorescence, and 1H NMR spectra indicated that the fluorescence quenching can be attributed to the strong hydrogen bonding interaction between anions and imidazole group of Eu-complex. To meet application requirements for biological and environmental detection in water, we successfully prepared a Eu-based fluorescent hydrogel probe using Eu(TTA)2vinyl-phen and N-isopropyl acrylamide (NIPAAm) as monomers through free radical copolymerization in DMF. Emission spectra titration experiments indicated that this hydrogel probe can effectively recognize H2PO4 − (detection limit 10−5 M), but cannot recognize F− and CH3COO− in pure water. To the best of our knowledge, this is first report that Eu-based fluorescent hydrogel probe for H2PO4 − detection in pure water. In addition, the emission of Eu-complex is also found to be sensitive to molecular oxygen through energy back-transfer mechanism. [Copyright &y& Elsevier]