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[Display omitted] • Highly stable perovskite nanocrystals in water were obtained by modifing wool keratin (WK) and crosslinking agent (PAPI). • CPB/WK-PAPI nanocrystals show excellent photoluminescence retention over time even after 512 days (>40 %). • Portable, low cost, and visualize test strips for amines were successfully made from these nanocrystals. Perovskite nanocrystals (PNCs) have emerged as promising candidates for fluorescent probes owing to their outstanding photoelectric properties. However, the conventional CsPbBr 3 (CPB) NCs are extremely unstable in water, which has seriously limited their sensing applications in water environment. Herein, we present a powerful ligand engineering strategy for fabricating highly water-stable CPB NCs by using a biopolymer of wool keratin (WK) as the passivator and the polyaryl polymethylene isocyanate (PAPI) as the cross-linking agent. In particular, WK with multi-functional groups can serve as a polydentate ligand to firmly passivate CPB NCs by the ligand exchange process in hot toluene; and then the addition of PAPI can further encapsulate CPB NCs by the crosslinking reaction between PAPI and WK. Consequently, the as-prepared CPB/WK-PAPI NCs can maintain ∼ 80 % of their relative photoluminescence (PL) intensity after 60 days in water, and they still maintain ∼ 40 % of their relative PL intensity even after 512 days in the same environment, which is one of the best water stabilities compared previously reported polymer passivation methods. As a proof-of their application, the portable CPB/WK-PAPI NCs-based test strips are further developed as a fluorescent nanoprobe for real-time and visual monitoring amines and food freshness. Among various amine analytes, the as-prepared test strips exhibit higher sensitivity towards conjugated amines, achieving a remarkable detection limit of 18.3 nM for pyrrole. Our research not only introduces an innovative strategy involving natural biopolymers to enhance the water stability of PNCs, but also highlights the promising potential of PNCs for visually and portably detecting amines and assessing food freshness. [ABSTRACT FROM AUTHOR]

New homodimers of 1,2,3-triazolyl nucleoside analogs based on 6-methyluracil, which are linked by the polymethylene linker at the N(1) or N(3) atoms, were synthesized. Screening of in vitro antiviral activity against influenza A virus (H1N1) and Coxsackievirus B3 revealed the lead compound that in vitro inhibited the replication of Coxsackievirus B3 with a half-maximal inhibitory concentration (IC50) and a half-maximal cytotoxic concentration (CC50) of 30.1 and >374 µmol L−1, respectively. A dependence of the antiviral activity on the length of the polymethylene linker connecting the 6-methyluracil and 1,2,3-triazolyl-β-d-ribofuranosyl fragments was found. [ABSTRACT FROM AUTHOR]

A series of new dimers of pyrimidine nucleoside analogues have been synthesized. The dimers are composed of two uracil or thymine fragments linked at N3 through a polymethylene bridge and bearing a β-D-ribofuranose residue linked to N1 of the nucleobase through a 1,2,3-triazolylalkyl spacer. Biological screening revealed that some of the synthesized dimers are active against influenza A (H1N1) virus and coxsackievirus B3 with IC50 values of 13 and 4.5 μM, respectively. [ABSTRACT FROM AUTHOR]

In this work, a series of semi‐crystalline semi‐aromatic poly (ether amides) (PAT‐2–PAT‐10) with varying length of polymethylene moiety (2, 4, 6, 8 or 10 methyl groups) and number of ether groups in the main chain were synthesized by the nucleophilic substitution reaction of semi‐aromatic difluorobenzamido alkanes with 1, 4‐benzenediol at about 190–200°C, using K2CO3 as catalyst, N‐methyl pyrrolidione (NMP) as reaction solvent. And their viscosities, thermal, and mechanical properties were investigated. The inherent viscosities, glass transition, melting and degradation temperatures and tensile strength values of the synthesized polymers were in the range 0.141–1.829 dL g−1, 119.1–165.0°C, 272.4–345.4°C, and 371.4–451.1°C, and 61.2–79.2 MPa respectively. Moreover, they were found to have good solubility in concentrated sulfuric acid and trifluoroacetic acid at room temperature. The length of poly methylene group and ether bond in the polymer main chain had significantly influenced their thermo mechanical properties. The polyamides PAT‐6–PAT‐10 had better thermo mechanical property than that of commercial polyamide, PA6T/66. [ABSTRACT FROM AUTHOR]

Stretched all-trans conformations were found preferable in computed structures of bis-imidazolium dications with short aliphatic (С1–С4) and hydroxyl substituted –СН2–СНОН–СН2– bridges. The molecular electrostatic potential is distributed unevenly in the dications: maxima of molecular electrostatic potential are located near С2Н imidazolium and bridge hydrogens for the α,ω-alkenyl bridges, and close to hydroxyl hydrogen for the hydroxypropane bridge. Intramolecular hydrogen bonds С–Н···ОН contribute to a significantly higher rotational barrier around С1–C2 bond in dications with a hydroxypropane bridge compared with polymethylene bridges. [ABSTRACT FROM AUTHOR]

A number of α,ω-bis(2-acetylphenoxy)alkanes have been synthesized with a yield of 40–90% by alkylation of 2′-hydroxyacetophenone with α,ω-dihaloalkanes. The X-ray data had allowed to reveal an effect of the size of the polymethylene linker on the conformations of α,ω-bis(2-acetylphenoxy)alkanes, which affect the melting points and are manifested in the UV spectra. A hypothesis that the conformation of α,ω-bis(2-acetylphenoxy)alkanes is determined by noncovalent interactions has been made on the basis of quantum-chemical calculations. Evaluation of the selectivity of the reaction of α,ω-bis(2-acetylphenoxy)alkanes with the entire series of alkali metal ions has demonstrated that a increase in the size of the polymethylene linker along the homologous series leads to an increase in the selectivity of the reaction with sodium ions, when the linker contains an odd number of methylene groups and with sodium and potassium ions, when the linker contains an even number of methylene groups. [ABSTRACT FROM AUTHOR]

This paper considers a scan method to measure mechanical stresses for a photoelastic material by the value of the reflection coefficient difference of orthogonal linearly polarized light waves. The results of the estimation of the stress state of a poly(methyl methacrylate) sample using the proposed reflective method are described. The dependencies of change induced by stress birefringence in the stressed sample from the displacement of the measuring beam transverse to the compression axis and along the axis are given. The case of almost normal incidence of light is considered. [ABSTRACT FROM AUTHOR]

The polymerization of 2,3,4,5,6‐pentafluorobenzyl 2‐diazoacetate is conducted at ambient temperature and catalyzed by [(l‐prolinate)RhI(1,5‐dimethyl‐1,5‐cyclooctadiene)] or [(l‐prolinate)RhI(1,5‐cyclooctadiene)] yielding C1 polymers with molecular weights of 3000–4000 g mol−1 and dispersity between 1.1 and 1.3. Incorporation of the pentafluorobenzyl group into the C1 polymer results in a different solubility when compare to its C2 analog poly(2,3,4,5,6‐pentafluorobenzyl methacrylate). Efficient postmodifications via para‐fluoro‐thiol reaction with different thiols are conducted with this C1 polymethylene. [ABSTRACT FROM AUTHOR]

[Display omitted] The reactions between Ph 3 As and ω-bromoalkanoic acids with the length of polymethylene fragment n = 5, 7, 9 afford quaternary arsonium salts. Their treatment with alkali gives biologically active arsenobetaines. Solvent-free reactions of Ph 3 P or Ph 3 As with 2,3-dibromopropionic acid lead to the corresponding arsonium and phosphonium salts bearing (CH 2) 2 COOH substituent. [ABSTRACT FROM AUTHOR]

The present work reports a newly prepared Schiff base bis(pyrrole-2-carboxaldehyde)-o-phenylenediimine and its Schiff-based resin polymethylene bis(pyrrole-2-carboxaldehyde)-o-phenylenediimine via condensation with formaldehyde (HCHO) at 120–130°C for 1–2 h. Schiff bases (also well known as azomethine or imine), named after Hugo Schiff, described by Schiff (1864) in the nineteenth century. A compound having an azomethine group (–HC=N–p), well known as Schiff base is prepared by condensation of a primary amine with a carbonyl compound. Schiff bases with metal ions are necessary for the improvement of the coordination chemistry field. The synthesised Schiff base and its resin were recrystallised and melting point was recorded. The prepared material was characterised by, CHN Analysis, Fourier Transform Infrared Spectroscopy (FTIR), Ultraviolet-Visible Spectroscopy (UV-Visible), and SEM analysis. Afterwards, synthesised Schiff-based resin was encapsulated by metal nanoparticles MgO@SiO2 and resulted in the material is polymethylene bis(yrrole-2-carboxaldehyde)-o-phenylenediimine magnesium oxide nanoparticles (PMBPCPhenMgO). The adsorption capacity for removing Cu (II) from the aqueous solution was evaluated. The result encapsulated material was used as adsorbent and showed that Schiff-based resin-encapsulated metal nanoparticles are an attractive alternative adsorbent material for the Cu (II) ions removal from aqueous solution. [ABSTRACT FROM AUTHOR]

A 3‐year‐old spayed female German Shepherd dog was presented for investigation and treatment of a firm slow growing mass over the right surface of the skull. Computed tomography (CT) of the head revealed a proliferative, rounded and well‐defined compact bone mass expanding extracranially. A right rostrotentorial craniectomy was performed with 'en bloc' mass resection. To achieve clear margins, the excision of the outer table of the frontal bone, with subsequent opening of the right frontal sinus, was necessary. To provide an appropriate sealing between the cranial cavity and the nasal cavity, thereby preventing future complications, a cemented partial obliteration and reconstruction of the right frontal sinus was performed. The dog recovered uneventfully. Histopathological analysis confirmed complete resection with clear margins and the final diagnosis of an osteoma. The dog was progressing with no clinical signs 8 months after the surgery. [ABSTRACT FROM AUTHOR]

Polyacrylates bearing long fluoroalkyl (Rf) side chains are known to have ultralow surface energies that are appropriate for functional coating and fabric finishing. However, these long Rf chains cause health concerns because of the risk of toxic and bioaccumulative perfluoroalcanoic acid emission via oxidative degradation. This work demonstrates that incorporating a short Rf chain of perfluoroethylene at the end of the side chains of syndiotactic poly(substituted methylene) (PM) produces hydrophobicity. A contact angle of 105° of PM remains constant for more than 50 s, whereas that of the polyacrylate (PA) with the same side chain rapidly decreases from 85° to 44° over the same period. Such persistent water repellency of the PM is ascribed to a liquid crystal structure comprised the main chains arranged in a 2D hexagonal lattice and side chains that extend perpendicularly from these main chains. [ABSTRACT FROM AUTHOR]

The paper describes an investigation of structural and geochemical properties of genetically similar crude oils from the Turija-sever field located in the South-Eastern Pannonian Basin, Serbia. Samples from 56 wells were examined by infrared spectroscopy (IR) and gas chromatography (GC). The IR spectral region of 2800– 3000 cm–1 was modeled by the sum of Lorentzian functions to reveal the contributions of aliphatic stretching vibrations, from which the alkane branching factor was evaluated. Being dependent on the aliphatic chain branching, the CH2 absorption peaks shifted by 3–4 cm–1 towards high frequencies when passing from the least-branched to the most-branched oil samples. This is associated with an increase in the fraction of gauche-conformations in polymethylene fragments. GC data shows the similarity of Turija-sever oils in thermal maturity, corresponding to to the early stage of liquid hydrocarbon generation and revealing a mixed aquatic-terrigenous origin of the precursor organic matter (OM) generated in a transitional reducing to weakly oxidizing depositional environment. In view of a significant correlation revealed between the alkane branching and the geochemistry, the samples were readily divided into two groups. Specifically, oils of Group I have a higher contribution of algae to the precursor OM and were generated under more reducing conditions than oils of Group II. The obtained data demonstrates in practice the advantage of the GC-IR combination to explain the structural and geochemical properties of sedimentary OM. [ABSTRACT FROM AUTHOR]

[Display omitted] • Flexible polymethylene trisulfide/rGO electrodes with a specific capacity of 366 mAh/g are developed. • The microstructure/electrochemistry relationship of flexible electrodes is explained. • The extent of chain moveability directly affects the electrochemistry in these electrodes. Flexible polysulfide electrodes can play a crucial role in the future development of wearable energy storage devices. Understanding the electrochemical energy storage mechanism in these electrodes can guide the engineering of polysulfides and their composites to design high-performance flexible energy storage devices. Polymethylene trisulfide (PMTS) and PMTS/reduced graphene oxide (rGO) nanocomposites, synthesized via in-situ interfacial polymerization, are introduced as active materials for developing high-performance electrodes. The fundamental scientific objective of this study is to uncover the correlation between the microstructural properties of linear polysulfides and the electrochemical behavior of low molecular weight intermediate polysulfide species. Based on microstructural studies, Coulomb interactions between rGO and PMTS macromolecules dictate PMTS chain confinements. Such molecular confinements affect the glass transition temperature and the crystallinity of PMTS, hence controlling the electrochemistry of electrodes. A high specific capacity of 366 mAh/g (5 μA) is reached using the flexible PMTS/0.5 wt% rGO nanocomposite electrode in Li-PMTS cells. The suggested mechanism for the anodic and cathodic polarizations in Li-PMTS cells is based on the formation of low molecular weight sulfide polymeric species. Therefore, the crystallinity and moveability of polymeric chains are introduced as structural features of polysulfide electrodes that can be utilized to improve the performance of energy storage systems based on these active materials. [ABSTRACT FROM AUTHOR]

• Novel BPE-ECL biosensor based on DNA network was developed for S. aureus assay. • Synergic amplification effect based on target-triggered PCR and pMB NPs was used. • Three-dimensional Au-DNA network allows for the loading of plenty pMB NPs. • The electrochemical reduction of pMB NPs could greatly amplify the ECL intensity. A novel bipolar electrode (BPE)-electrochemiluminescence (ECL) device was constructed for the ultra-sensitive detection of Staphylococcus aureus (S. aureus) by combining polymerase chain reaction (PCR) amplification and DNA network-loaded polymethylene blue nanoparticles (pMB NPs). The presence of target triggered the dissociation of double-stranded DNA on Fe 3 O 4 NPs and the release of T strand, which initiated the PCR. The PCR product contains two protruding single-stranded DNA fragments that serve as bridges to connect Au NPs labeled probes. The PCR-Au products were captured by the probes on cathode of BPE to form three-dimensional DNA networks, which offer multiple adsorption sites for pMB NPs, leading to the remarkable enhancement of ECL intensity. Under optimal circumstances, a wide linear range from 10 to 108 CFU/mL and a low detection limit of 0.78 CFU/mL were achieved. This research opens new horizons for the application of PCR-based biosensors for the accurate and sensitive measurement of pathogenic bacteria. [ABSTRACT FROM AUTHOR]

A number of novel amides were synthesized by coupling of 6-[(9H-purin-6-yl)amino]hexanoic acid to heterocyclic amines. The antiviral activity of the obtained compounds, as well as of purine conjugates in which 7,8-difluoro-3-methyl-3,4-dihydro-2H-1,4-benzoxazine is linked to position 6 of purine through a fragment of ω-amino acids with varying lengths of polymethylene chains against influenza A and B viruses was studied in vitro. Purine derivatives have been shown to have moderate activity against influenza A (H1N1) virus. The antiinfluenza activity and cytotoxicity of conjugates with 7,8-difluoro-3-methyl-3,4-dihydro-2H-1,4-benzoxazine depend on the length of the linker fragment. [ABSTRACT FROM AUTHOR]

It is of great importance to determine the quantification of glucose in human serum. In this work, a novel NiO nanoflower/ polymethylene blue (NiO/PMB) modified glassy carbon electrode (GCE) was fabricated and taken as a non-enzymatic glucose biosensor. The composite was characterized by field-emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD). The electrochemical properties of the modified biosensor were investigated by the cyclic voltammetry (CV) method. This biosensor combined the advantages of NiO nanoflower and PMB, so that a series of characterization results indicated that the composite material exhibiting satisfactory catalytic activity towards glucose. The quantitative determination of glucose was carried out by chronoamperometric measurements (i–t) method and showed linear ranges between 3−50 μM and 50−80 μM, with the limit of detection (LOD) of 2 × 10 −7 M (S/N = 3). Under optimal conditions, the sensitivity of the self-assemble biosensor was calculated to be 413.06 μ A cm −2 mM−1 for glucose. The selectivity, reproducibility, and stability of the glucose biosensor were also confirmed in the study. In addition, this glucose biosensor was successfully applied for the analysis of glucose in real human serum samples. [ABSTRACT FROM AUTHOR]

A hybrid nanoparticles light emitting diode (NPs-LED) was fabricated as layers of ITO/TPD:PMMA/ Eu2O3 / Alq3 / Al, by phase segregation method using spin coating technique. The NPs-LED hybrid device emitted light and consisted of three layers in a definite order placed on the transparent conducting oxide as an ITO substrate; the first layer was made of (N, N'-bis (3-methylphenyl) -N, N'-bis (phenyl) benzidine) (TPD) and polymethyl methacrylate (PMMA) polymers combined together. The second layer consisted of Europium (III) oxide (Eu2O3), while the third layer was Alq3, one of the most frequently-used electron transport layers. The electroluminescence (EL) of NPs-LED was studied with different bias voltages (20, 25 and 30V) at room temperature. Depending on the CIE 1931 color spaces, X the white light was generated at 30V and the green light at 20V. This was achieved by benefitting from the transition between deep levels in the energy gap of Eu2O3 NPs (surface state ) and magnetic dipole transition for Eu+ (5D0-3and5L6 to 7F0-6). The Current – Voltage (I-V) characteristics demonstrated that the current varies with voltage and that the knee voltage value is 5 V. The EL spectrum showed a broad band emission, with a range of 350 - 700 nm. Finally, the correlated color temperature (CCT) was found to be about 7100 to 11500k. [ABSTRACT FROM AUTHOR]

An enzyme electrocatalytic p16 protein (AGp16INK4a) immunosensor based on polymethylene blue (PMB) decorated on functional composite modified glassy carbon electrode (PG-GR-CS/GCE) is constructed successfully. The PG-GR-CS having good conductivity and large specific surface area is composed of graphene (GR) doped polycaprolactam 6 (PA6) electrospun nanofibers (PG), GR and chitosan (CS), which could serve as a stable electropolymerization substrate for increasing the amount of PMB. The active catalytic electrode (PG-GR-CS-PMB/GCE) was used as the platform for the construction of an electrocatalytic immunosensor, it can greatly increase the immobilization capacity of AGp16INK4a capture antibody (Ab1), and further catch the AGp16INK4a and horseradish peroxidase-labeled detection antibody (HRP@Ab2) through the sandwich immunoreaction. The PMB decorated on PG-GR-CS/GCE exhibited good electron transfer and electrochemical properties, which could apply as electrocatalytically nanomaterials. Thus, the amplified electrocatalytic response were produced by the reduction of enzymatically oxidized PMB in the presence of hydrogen peroxide via HRP. It was observed that the change of the differential pulse voltammetry of the PMB was proportional to the AGp16INK4a ranging from of 1.0 pg ml−1 to 1.0 ng ml−1 . The detection limit was down to 0.5 pg ml−1 . The successful immunosensor provides a promising alternative to the electrocatalytic detection of various tumor markers. [ABSTRACT FROM AUTHOR]

Sciadonic acid (Scia) is a Δ5-olefinic fatty acid that is particularly abundant in edible pine seeds and that exhibits an unusual polymethylene-interrupted structure. Earlier studies suggested that Scia inhibited the in vitro expression and activity of the Stearoyl-CoA Desaturase 1 (SCD1), the hepatic Δ9-desaturase involved in the formation of mono-unsaturated fatty acids. To confirm this hypothesis, rats were given 10% Scia in diets balanced out with n-6 and n-3 fatty acids. In those animals receiving the Scia supplement, monoene synthesis in the liver was reduced, which was partly attributed to the inhibition of SCD1 expression. As a consequence, the presence of Scia induced a 50% decrease in triglycerides in blood plasma due to a reduced level of VLDL-secreted triglycerides from the liver. In non-fasting conditions, results showed that Scia-induced inhibition of SCD1 led to a decrease in the proportions of 16:1n-7 and 18:1n-7 in the liver without impacting on the level of 18:1n-9, suggesting that only triglycerides with neosynthesized monoenes are marked out for release. In conclusion, this in vivo study confirms that Scia highly inhibits SCD1 expression and activity. The work was performed on normo-triglyceride rats over six weeks, suggesting promising effects on hyper-triglyceridemic models. [ABSTRACT FROM AUTHOR]

The transient absorbance of poly(4-methyl-1-pentene) (PMP) irradiated with gamma rays at elevated temperatures has been investigated. The absorbance in the ultraviolet and visible range increases with gamma ray dose. A bathochromic shift in transmission spectra emerges significantly upon irradiation. A first-order generation model is proposed to analyze the kinetics of color centers during annealing. The activation energy of the color center increases with increasing gamma ray dose. The equilibrium behavior of color centers in PMP is similar to that of vacancies in metals, and the formation energy of color centers in PMP decreases with increasing gamma ray dose. However, annealable color centers are not observed in this study. [ABSTRACT FROM AUTHOR]

CO2 laser micromachining provides a flexible and low-cost means for the rapid prototyping and manufacturing of miniaturized polymer systems such as polymethyl methacrylate (PMMA) microfluidic chip devices. In this paper, the relationships between the process variables (profile and depth of laser-ablated channels) and the process parameters (laser power and scanning velocity) are investigated. In contrast with the fabrication of 100–500 μm wide channels reported in previous work, we focus on the fabrication of narrower channels using low laser power which can reduce the cost of the fabrication system and low scanning speeds. In this work, the laser power used for channel fabrication ranged from 0.45 to 1.35 W and the scanning speeds ranged from 2 to 14 mm/s. The width of fabricated channels ranged from 44 to 240 μm and their depths ranged from 22 to 130 μm. Physical models were developed for predicting the depth and the profile of laser-ablated channels. The profile model incorporates the threshold fluence for CO2 laser ablation of PMMA to account for the partial ablation across the beam diameter. Our models are in excellent agreement with experimental results, with a maximum deviation of approximately 5%. [ABSTRACT FROM AUTHOR]

The reactions of allyl ethyl, allyl butyl, allyl glycidyl, allyl benzyl, and allyl phenyl ethers with 1,1,3,3-tetra-methyldisiloxane in the presence of platinum(II) immobilized on polymethylene sulfide have been studied. [ABSTRACT FROM AUTHOR]

In this work, a binary-mixed-brushes-coated (BBC) capillary with switchable protein adsorption/desorption properties was developed and applied for on-line preconcentration of proteins. Firstly, amine-terminated poly(2-methyl-2-oxazoline) (PMOXA-NH2) and thiolterminated poly(acrylic acid) (PAA-SH) were synthesized by using cationic ring-opening polymerization (CROP) and reversible addition fragmentation chain transfer (RAFT) polymerization, respectively. Then, the BBC capillary based on poly(2-methyl-2-oxazoline) (PMOXA) and poly(acrylic acid) (PAA) was prepared by sequentially grafting of PMOXA-NH2 and PAA-SH onto fused-silica capillary inner surface through poly(dopamine) (PDA) as an anchor. The obtained PMOXA/PAA coating formed on the capillary or capillary's raw material was characterized in terms of the thickness, surface chemical composition by using scanning electron microscope (SEM) and X-ray photoelectron spectrum (XPS). The switchable protein adsorption/desorption performance of the BBC capillary was investigated by using fluorescence microscope under different solutions with certain pH and ionic strength (I). The results showed that bovine serum albumin (BSA) could be adsorbed on BBC capillary at pH=5.0 (I=10−5 mol/L), and then the adsorbed BSA could be released at pH=9.0 (I=0.1 mol/L). This switchable protein adsorption/desorption property of coated capillary was then used to preconcentrate proteins on-line for increasing the detection sensitivity of BSA in capillary electrophoresis (CE). With this method, a sensitivity enhancement factor (SEF) more than 5000 for BSA detection was obtained. [ABSTRACT FROM AUTHOR]

Poly(methylene-co-cyanoguanidine), PMCG, is an oligomeric polycation that has found its application in the waste-water treatment as well as in preparation of polyelectrolyte complex microcapsules for biomedical purposes. Considering the nitrogen-rich composition of repeating unit, PMCG may be a valuable polycation utilized as a novel slow-release fertilizer. The aim of this study was to evaluate the potential of PMCG as a nitrogen fertilizer during its 6-month incubation in the soil. Monocotyledonous oat (Avena sativa) and dicotyledonous radish (Raphanus sativus L.) were selected as representative model plants for plant growth test. The effect of PMCG on plant growth and development was dependent on both the PMCG concentration and time of incubation. An increase in the nitrogen amount in green parts of plants demonstrated the uptake of the plant-available form of nitrogen released from PMCG incubated in the soil. This resulted in an increased percentage of fresh matter and shoot height of the tested plants during their exposure to PMCG. Ecotoxicological impact of PMCG in the soil during incubation period against bacteria Allivibrio fischeri and crustacean Heterocypris incongruens was also assessed. PMCG was found as the potential polymer fertilizer that does not require special treatment and can be used as it is for the prolonged release of nitrogen in agriculture. [ABSTRACT FROM AUTHOR]

Montmorillonite of natural modification with organic complexes was found for the first time in bentonite of the Tikhmenevo deposit on Sakhalin Island. The data obtained permitted us to identify within the interlayer space of the bentonite chain polymethylene, alkylammonium, and other fragments of humic molecules occurring in the humus surrounding the bentonite. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • LCST behavior can be tuned through the copolymerization between 3M2P and N -butyl methacrylamide. • LCST behavior can be tuned through the introduction of an N -ethyl or N -propyl substitution on 3M2P. • LCST behavior can be manipulated by the addition of salts from the Hofmeister series. Abstract The thermoresponsive behavior of a 3-methylene-2-pyrrolidone (3M2P), its copolymer with N -butyl methacrylamide (N -BuMAAm), a hydrophobic monomer, and 3M2P's N -alkylated derivatives was investigated. P3M2P did not display a cloud point within the measurable temperature range, even in the presence of high concentrations of strongly kosmotropic Hofmeister salts. The copolymer of 3M2P with N -BuMAAm, and the homopolymers of P3M2P N -alkylated with ethyl and propyl groups demonstrated thermoresponsive behavior, whilst N -methylation did not introduce a sufficient hydrophobic character, to impart thermoresponsivity to the P3M2P system. The reversibility of the thermal phase transition, and the influence of experimental conditions, i.e. (co)polymer concentration, heating rate and Hofmeister salts, on the thermoresponsivity of the (co)polymers was also investigated, to assess the potential of the P3M2P derivatives as thermoresponsive polymers. [ABSTRACT FROM AUTHOR]

The article discusses the presence of macromolecules in biology, research, and in practice. The author reflects that biological materials are more efficient than man-made materials from plastics, wood, metal or ceramics. He describes macromolecular structure of biological materials and their mechanisms and the underlying principles on how they may be used in various industries. He discusses several macromolecular material which can be used to create biological machines such as polymethylene, rubber, plastics, and polyelectrolytes.

Graphical abstract Highlights • Dendritic PMB film formed on Cu-CNF/ACF using electropolymerization. • Polymer-metal-carbon nanocomposite used as the electrode of a creatinine-biosensor. • Measurements showed fast response of the sensor with 0.2 ng mL−1 detection limit. • Successful measurements of creatinine in the biological samples including saliva. Abstract Creatinine is a preferred biomarker for the renal dysfunction, and its selective determination in various biological fluids is useful for the evaluation of renal, muscular and thyroid dysfunctions. Development of a selective and sensitive non-enzymatic electrochemical sensor having a linear response and good stability over a wide range of creatinine concentration is challenging. In this study, a polymeric dye-based metal-carbon nanofiber nanocomposite was successfully fabricated as the electrode of a non-enzymatic electrochemical sensor for creatinine in human biological fluids. Using cyclic voltametry technique, the dendritic poly methylene blue (PMB) nanofibers were electrochemically grown on the surface of the Cu-doped carbon electrode. The PMB molecule acted as a recognition element for creatinine. In virtue of the structural merits and synergistic contribution of the polymer-metal-carbon nanofiber nanocomposites in enhancing the electrocatalytic activity towards creatinine, the fabricated electrode exhibited good sensing performances including a high sensitivity of 0.133 μA ng mL−1, a linear response over 0.5–900 ng mL−1 conentration range and the detection limit of 0.2 ng mL−1 (with a signal-to-noise ratio of 3:1), as well as good selectivity. The proposed electrochemical sensor can be used for the real time detection of creatinine in biological fluids. [ABSTRACT FROM AUTHOR]

This work focus on improving the heat resistant and mechanical properties of poly(lactic acid)/poly (butylene succinate) (PLA/PBS) blends using appropriate contents of polyaryl polymethylene isocyanate (PAPI). Some crosslinked structures were formed according to the gel fraction and rheological results, and the crosslinked structures played the role of nucleation site for the blends. And the Vicat softening temperature of the blends gradually increased with increasing PAPI content. Moreover, the addition of PAPI in the PLA/PBS blends produced a few PLA-PBS copolymers which acted as a compatibilizer and enhanced the interfacial adhesion. Thus, the mechanical properties of PLA were significantly improved. [ABSTRACT FROM AUTHOR]

A series of poly(acrylic acid)/poly(methyl vinyl ketone) (PAA/PMVK) blends with different compositions were prepared by the solvent casting method. The miscibility of this pair of polymers was investigated by differential scanning calorimetry(DSC), Fourier transform infra-red (FTIR) and X-Ray diffraction (XRD) techniques. An in-vitro cytotoxicity test of the drug-carrier system via MTT (3-(4,5-demethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay revealed no significant cytotoxic effects at concentrations up to 100 µg· ml−1. The STX/PAA-50 drug carrier systems were also prepared by solvent casting of solutions containing the sulfamethoxazole (STX) used as drug model and PAA/PMVK blend in N.N-dimethylformamide then crosslinked with acidified ethylene glycol. The release dynamic of STX from the prepared hydrogels was investigated in which the diffusion through the polymer matrix, the enhancement of the water solubility of STX, the influence of the initial drug concentration, the pH of the medium, and the effect of the degree of swelling of the polymer matrix on the release dynamic was evaluated. According to the total gastrointestinal transit time estimated by Belzer, the estimate distribution of STX released in the different organs indicated that the performance is obtained with the drug - carrier-system containing equal ratios of polymer and 10 wt% of STX (STX-10/PAA-50). [ABSTRACT FROM AUTHOR]

Planar chiral, trans‐bis(salicylaldiminato)palladium(II) complexes having a macrocyclic vaulting structure consisting of either a heptamethylene‐butadiynylene‐heptamethylene (1) or polymethylene (2) bridge were synthesized and subsequently characterized by NMR, IR, high‐resolution mass spectrometry, and single crystal XRD. The dynamic rotational behaviors of these vaulted complexes resulting from a skipping‐rope‐like molecular motion were examined on the basis of kinetic studies of the racemization of the optically pure (100 % ee) complexes. The chiral inversion rate was found to be significantly affected by the conformational flexibility of the complexes, which in turn could be controlled by adjusting the linker length, the linker rigidity, and the ligation properties of the solvent. The dynamic rotational behaviors of vaulted complexes based on a skipping‐rope‐like molecular motion were examined using kinetic studies of the racemization of optically pure complexes bearing rigid or flexible carbon chain linkers in various solvents. [ABSTRACT FROM AUTHOR]

A novel approach to the synthesis of α-amino-ω-nucleo carboxylic acids, analogs of willardiin, an activator of the receptor of α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid, which is responsible for the transfer of a fast stimulating signal in the synapses of the nervous system of vertebrates, is proposed. Based on substantial differences in the reactivity of halogen atoms in α,ω-dihalogen carboxylic acids, the esters of α-phthaloylimido-ω-chloro carboxylic acids have been synthesized. The alkylation of uracil, thymine, and adenine with these esters gave the key compounds, the esters of α-phthaloylimido-ω-nucleo carboxylic acids. The consecutive removal of the phthalyl protective group and acid hydrolysis led to new polymethylene derivatives of nucleic bases, which are α-amino-ω-nucleo carboxylic acids. The physical and chemical properties of these compounds were studied. [ABSTRACT FROM AUTHOR]

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Graphical abstract Highlights • Efficient triazole synthesis under microwave irradiation. • Practical approach to polymethylene-bis(1 H -1,2,4-triazol-5(3)-amines) • One-pot synthesis of 1,2,4-triazoles in aqueous media. • Tautomerism in 1,2,4-triazoles. Abstract A highly selective and efficient method for the synthesis of 3,3′(5,5′)-polymethylene-bis(1 H -1,2,4-triazol-5(3)-amines) was developed using the reaction of dicarboxylic acids and aminoguanidine in an aqueous medium. This one-pot, microwave-promoted method was proved to be scalable affording the desired products in good yields and purity. The scope of the method was successfully explored by the preparation of a small library of polymethylene-bis(1 H -1,2,4-triazol-5(3)-amines) with different alkyl chain linkers. The annular prototropic tautomerism in the prepared compounds was studied using NMR spectroscopy and X-ray crystallography. [ABSTRACT FROM AUTHOR]

The syntheses, structures and optical properties of polymethylene-vaulted trans -bis(2-aminotroponato)palladium(II) complexes are described. A series of Pd complexes incorporating nona-, deca-, undeca- and dodecamethylene bridges ( 1a : n = 9; 1b : n = 10; 1c : n = 11; 1d : n = 12) was newly prepared by reacting Pd(OAc) 2 with the corresponding N , N ’-[alkane-1,ω-diylbis(azanediyl)]ditropone. NMR and single-crystal X-ray diffraction analyses unequivocally established the specific structures of these complexes, including trans -coordination and three-dimensional vaulted structures. The photophysical properties of 1a – d exhibit a significant linker length dependence in 2-methyl-2,3,4,5-tetrahydrofuran, such that the absorption wavelengths in the vicinity of 420 nm are red-shifted as the linker length is decreased. This trend is the opposite to that observed in the corresponding vaulted trans -bis(salicylaldiminato)Pd(II) analogues 2a – d under similar conditions. The mechanistic rationale for the specific linker-dependence of the absorption wavelengths of 1 is discussed in comparison with that of 2 , based on molecular structures and electronic configurations. [ABSTRACT FROM AUTHOR]

Abstract: A procedure is developed for the determination of technical polymethylene naphthalene sulfonates (TPNS) in concrete by HPLC. The presence of 9.8-18.8% of a fraction with a low adsorption activity in TPNS is detected. A correlation is found between the initial slump of the concrete mix cone and the refined amount of oligomers of polymethylene naphthalene sulfonic acids with n ≥ 11, contained in TPNS. [ABSTRACT FROM AUTHOR]

Ethylene propylene diene polymethylene (EPDM) rubber is one of the fastest growing synthetic rubbers in the market. It is widely used in many fields due to its easy processing and high resistance against outdoor conditions compared to other rubber types. However, like all organic compounds, over time it is degraded under weathering conditions such as radiation, heat, ozone and chemical media, all of which can contribute to loss of bulk properties and reduce its service life. Cracks, discoloration, breakage, or staining can occur on the surface of visible automotive profiles due to the effect of UV light. These phenomena are definitely undesirable. In this study, five different EPDM rubber compounds (control and four different Flamestab® NOR 116 concentrations) were produced. The effects of the Flamestab NOR 116 were investigated by mechanical and rheological tests and ageing using the internationally recognised Florida artificial weathering test. The aged surfaces were visually scrutinised and surface morphological changes were examined via scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analyses. The results obtained showed that Flamestab® NOR 116 can be used as a UV stabiliser for EPDM rubber applications if it is added in amounts of between 1.25 and 2.0 phr. [ABSTRACT FROM AUTHOR]

Cardiac potassium channels encoded by human ether-à- go-go-related gene (hERG) are major targets for structurally diverse drugs associated with acquired long QT syndrome. This study characterized hERG channel inhibition by a minimally structured high-affinity hERG inhibitor, Cavalli-2, composed of three phenyl groups linked by polymethylene spacers around a central amino group, chosen to probe the spatial arrangement of side chain groups in the high-affinity drug-binding site of the hERG pore. hERG current (IhERG) recorded at physiological temperature from HEK293 cells was inhibited with an IC50 of 35.6 nM with time and voltage dependence characteristic of blockade contingent upon channel gating. Potency of Cavalli-2 action was markedly reduced for attenuated inactivation mutants located near (S620T; 54-fold) and remote from (N588K; 15- fold) the channel pore. The S6 Y652A and F656A mutations decreased inhibitory potency 17- and 75-fold, respectively, whereas T623A and S624A at the base of the selectivity filter also decreased potency (16- and 7-fold, respectively). The S5 helix F557L mutation decreased potency 10-fold, and both F557L and Y652A mutations eliminated voltage dependence of inhibition. Computational docking using the recent cryo-EM structure of an open channel hERG construct could only partially recapitulate experimental data, and the high dependence of Cavalli-2 block on Phe-656 is not readily explainable in that structure. A small clockwise rotation of the inner (S6) helix of the hERG pore from its configuration in the cryo-EM structure may be required to optimize Phe-656 side chain orientations compatible with high-affinity block. [ABSTRACT FROM AUTHOR]

ABSTRACT: α‐Methyleneglutaric acid, a metabolite of niacin (nicotinic acid), can be easily converted to its cyclic anhydride. We report here the first conversion of α‐methyleneglutaric anhydride to (a series of) α‐methyleneglutarimides. These monomers can be radically polymerized to the title polymers. These have relatively high glass transition properties compared to the lower homologs derived from itaconimides (α‐methylenesuccinimides). © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 1020–1026 [ABSTRACT FROM AUTHOR]

Single-molecule surface-enhanced Raman spectroscopy (SERS) offers new opportunities for exploring the complex chemical and biological processes that cannot be easily probed using ensemble techniques. However, the ability to place the single molecule of interest reliably within a hot spot, to enable its analysis at the single-molecule level, remains challenging. Here we describe a novel strategy for locating and securing a single target analyte in a SERS hot spot at a plasmonic nanojunction. The "smart" hot spot was generated by employing a thiol-functionalized cucurbit[6]uril (CB[6]) as a molecular spacer linking a silver nanoparticle to a metal substrate. This approach also permits one to study molecules chemically reluctant to enter the hot spot, by conjugating them to a moiety, such as spermine, that has a high affinity for CB[6]. The hot spot can accommodate at most a few, and often only a single, analyte molecule. Bianalyte experiments revealed that one can reproducibly treat the SERS substrate such that 96% of the hot spots contain a single analyte molecule. Furthermore, by utilizing a series of molecules each consisting of spermine bound to perylene bisimide, a bright SERS molecule, with polymethylene linkers of varying lengths, the SERS intensity as a function of distance from the center of the hot spot could be measured. The SERS enhancement was found to decrease as 1 over the square of the distance from the center of the hot spot, and the single-molecule SERS cross sections were found to increase with AgNP diameter. [ABSTRACT FROM AUTHOR]

The dilational properties of anionic gemini surfactants alkanediyl-α,ω-bis(m-octylphenoxy sulfonate) (C8CmC8) with polymethylene spacers at the water-air and water-decane interfaces were investigated by oscillating barriers and interfacial tension relaxation methods. The influences of oscillating frequency and bulk concentration on the dilational properties were explored. The experimental results show that the linking spacer plays an important role in the interfacial dilational properties. The moduli pass through one maximum for all three gemini surfactants at both water-air and water-decane interfaces. However, the values of moduli at the water-air interface are obviously higher than those at the water-decane interface because the sublayer formed by spacer chains will be destroyed by the insertion of oil molecules. Moreover, with the increase of spacer length, the surface adsorption film becomes more viscous at high concentration, which can be attributed to the process involving the formation of the sublayer. On the other hand, the spacers of the adsorbed C8C6C8 molecules will extend into the oil phase when the interface is compressed. As a result, the interfacial film becomes more elastic with the increase of spacer length at high concentration. The experimental results obtained by the interfacial tension relaxation measurements are in accord with those obtained by the oscillating barriers method. [ABSTRACT FROM AUTHOR]

Although crystallization-driven self-assembly (CDSA) of semi-crystalline block copolymers (BCPs) affords one of the most promising approaches to tailor novel asymmetric nanostructures, crystalline BCPs’ response to external interactive additives remains less understanding. In the present work, the interactive disturbance effect of CaCl 2 additive on CDSA of semi-crystalline polymethylene- b -poly(acrylic acid) diblock copolymers (PM- b -PAA) was systematically studied. It was found that pre-formed crystalline disklike BCP micelles obtained from CDSA could be drawn closely and bridged by Ca 2+ cations, leading to merging and crystallization of PM cores as well as BCP morphological evolution. Particularly, an increasing epitaxial crystallization together with morphological transition from disklike BCP micelles to worm-like micelles, incomplete networks, and reticulate aggregates was successively observed as the stoichiometric ratio of [Ca 2+ ]/[COOH] increased from 0 to 2. The complexation between Ca 2+ and ionized carboxylic groups on the PAA segments was evidenced by Fourier transform infrared (FTIR) measurement, and could be tuned by manipulating solvent quality, solution pH, and block composition. In addition to interactive disturbance effect, pronounced saltingout effects, displayed at excessive amount of CaCl 2 salt, resulted in dehydration and serious aggregation of BCPs. [ABSTRACT FROM AUTHOR]

An experimental investigation was conducted to study the effect of branch channel diameters on phase distribution behaviors of the two-phase flow in horizontal microimpacting T-junctions. The cross-section of the inlet channel was 1000 μm × 500 μm and the cross-sections of the branch channels were 400 μm × 500 μm, 600 μm × 500 μm, 800 μm × 500 μm, respectively. Nitrogen and pure water at 120 kPa (abs) and 25 °C were selected as the working fluids. A high speed recording camera was used to clarify the fluid dynamics of the gas–liquid two-phase flow in the test section. Combining above experimental results with the visualization data, the force mechanism of gas–liquid two-phase flow in microimpacting T-junction was analyzed. For the better application of microimpacting T-junctions, the separation efficiency was introduced to evaluate the separation effect. It was found that the uniformity of the phase distribution can be well improved with the decrease of the branch channel diameters. The influencing degree (I) on slug-annular flow was larger than that on slug flow and annular flow. Furthermore, the influencing degree (I) decreased as the superficial velocities of two phases increased when inlet was slug flow or annular flow. [ABSTRACT FROM AUTHOR]

• Screen-printed carbon electrodes were modified with ZnONR, PMB DES, and AuNP. • ZnONR, PMB DES , and AuNP were characterized by FE-SEM-EDX, FTIR, and XRD. • Electrochemical characterizations of the modified electrode were performed by CV, DPV, and EIS. • Disposable sensors were developed for voltammetric detection of 5-HT. • 5-HT levels in blood serum were measured using the fabricated sensor. Low or high levels of serotonin (5-HT) in the blood serum are linked to various diseases such as Alzheimer's, depression, anxiety, and carcinoid syndrome. In this study, a disposable sensor was developed for the low-cost, rapid, and practical determination of 5-HT. Firstly, zinc oxide nanorods (ZnONR) were modified on the surface of SPCEs by amperometric method. Then, electropolymerization of methylene blue (MB) on SPCE/ZnONR electrodes was carried out in ethylene glycol/choline chloride, a deep eutectic solvent (DES) suitable for green chemistry. Finally, AuNP was coated on SPCE/ZnONR/PMB (DES) electrodes by electrodeposition method. The materials of ZnONR, PMB(DES), and AuNP were characterized by FE-SEM-EDX, FTIR, and XRD. Sensitivity, linear range, the limit of detection, and limit of quantification of the 5-HT sensor were found to be 0.8976 µA µM−1, 0.1 µM – 25 µM, 1.91 nM, and 6.38 nM, respectively. Reproducibility, repeatability, stability (application and storage), reusability, and fouling effect of the 5-HT sensor were examined. The behavior of the developed 5-HT sensor in the presence of ascorbic acid, dopamine, uric acid, glucose, epinephrine, and norepinephrine, which are electroactive analytes that can interfere, was examined and it was found that the sensor was much more sensitive to 5-HT compared to other analytes. As a real sample application of the developed 5-HT sensor, the 5-HT determination was carried out in human blood serum samples, and high recoveries were obtained. As a result, a simple, practical, fast, high selectivity, sensitivity, repeatability, reproducibility, and the low-cost, disposable electrochemical sensor was developed for the determination of 5-HT. The developed 5-HT sensor can be used in point-of-care tests. [Display omitted] [ABSTRACT FROM AUTHOR]

Although the search of inhibitors of the key enzymes of HIV replication has remained a topical and intensively studied topic over the last several decades, potential inhibitors of the enzymes bearing thiocyano groups have been little studied. In this work, we tried to synthesize polymethylene derivatives of nucleic bases bearing thiocyano groups at the ω-position of the polymethylene chain. The reaction of new alkylating reagents, methyl α-thiocyano-ω-chloroalkanoates, with nucleic bases led to a complicated and barely separated product mixture. The only exceptions were the reactions of uracil or thymine with methyl 2-thiocyano- 2-chloropentanoate, in which 2-( N -uracilyl or -thyminyl)tetrahydrothiophene-2-carboxylates were isolated in 45-50% yields. The potential mechanism of the reaction is discussed. [ABSTRACT FROM AUTHOR]

Crystalline block copolymers tend to display a peculiar and intriguing behavior upon the external additives. In this work, we systematically investigated the self-assembly and crystallization behavior of polymethylene- b -poly (acrylic acid) crystalline diblock copolymer (PM- b -PAA, M 93 A 94 ) in the presence of calcium chloride (CaCl 2 ). When molar ratio between CaCl 2 and constituent deprotonated carboxyl group (COO − ) of M 93 A 94 (n, n = n CaCl2 /n COO − ) increased from 1:2 to 5:1, M 93 A 94 micelle gradually formed hexagonal and reticular aggregation. Further investigation of PM- b -PAA crystalline feature indicated that the crystallization of PM block was initially restrained by coordination interaction between calcium ion (Ca 2+ ) and carboxylate anion (COO − ), and then the crystallization of PM block was promoted when more Ca 2+ was added (n CaCl2 /n COO - reach to 5:1 and 13.5:1). Moreover, the conductivity measurement indicated that, when n (n CaCl2 /n COO − ) = 4, the coordination interaction between Ca 2+ and COO − was saturated, namely CaCl 2 /PAA formed tetradentate complex, and this information concerning the coordination geometry was highly consistent with the simulative calculation. [ABSTRACT FROM AUTHOR]

A C-pyrenyl poly(methylenephosphine) (Mn = 4800, Đ = 1.56) was synthesized from the anionic polymerization of a P-mesityl phosphaalkene. The phosphine oxide polymer exhibits blue fluorescence in solution (λmax 379, 400 nm, λonset 560 nm; Φ = 0.05) and blue-green fluorescence in the solid state at room temperature (λmax 460 nm, Φ = 0.07). In contrast, unoxidized polymer displays only a weak emission in solution and no emission in the solid state. Fluorescence studies of partially oxidized polymers (50, 75, 83% oxidation) indicate that “turn on” emission occurs only at very high degrees of oxidation (near 100%). We conclude that even a small number of unoxidized phosphine moieties within the partially oxidized polymer intramolecularly quench the fluorescence. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effects of hot water extraction process on the dimensional stability of oriented strand composites. Aspen wood strands were extracted using various severity factor levels. Phenol formaldehyde and polymethylene diphenyl diisocyanate resins were used for production of the oriented strandboard panels. Six panel groups were produced from the extracted or unextracted aspen wood strands. The dimensional stability of the material was evaluated by measures of equilibrium moisture content and thickness swell and water absorption after soaking in water for 2 hours and 24 hours. Results obtained in this study showed that thickness swell and water absorption values significantly decreased with the hot water extraction process, with the thickness swell of phenol formaldehyde bonded panels decreasing 70% after 2 hours soaking. The panels with polymethylene diphenyl diisocyanate resin exhibited lower thickness swell and water absorption relative to the panels prepared with phenol formaldehyde resin. Equilibrium moisture content values of the panels bonded with both phenol formaldehyde and polymethylene diphenyl diisocyanate resin decreased with the extraction process. The findings of this work indicate that hot water extraction process could be effectively used to produce oriented strand composites having an enhanced dimensional stability property. [ABSTRACT FROM AUTHOR]

In this paper, polyaryl polymethylene isocyanates (PAPI) were used as an innovative alternative material to prepare isocyanate microcapsules. PAPI could be used as core materials, which would react with small molecules containing active hydrogen (1,4-butanediol, ethylene glycol, 1,2-diaminoethane etc.). The reaction products of PAPI and active hydrogen would form a shell by interfacial polymerization reaction in an oil-in-water emulsion. Smooth spherical microcapsules of 70 ~ 180 μm in diameter were produced by controlling agitation rate (600 ~1200 rpm). High yields (~80%) of a free-flowing powder of PAPI/polyurethane and polyurea capsules were produced with a high isocyanate groups (-NCO) content of 23 wt % as determined by titration analysis. Structural analysis and quality assessments of each batch of microcapsules were performed by using thermogravimetric analysis, Fourier transform infrared spectroscopy and scanning electron microscopy. Preliminary results indicated the microcapsules were stable with only about 20% loss of -NCO detected after one month storage under ambient conditions. This work showed the great potential of novel microencapsulation technique in development of protection of -NCO and in aspects of micro- and nano-structure construction materials. [ABSTRACT FROM AUTHOR]