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Phenol is the toxicant present in cigarette smoke that causes pulmonary diseases, eyes infection, and even various kinds of cancer. So, in this research, an attempt was done to prepare a suitable absorbent to remove phenol from cigarette smoke. A novel bio-based adsorbent succinylated carboxymethyl starch (S-CMS) was prepared by reacting carboxymethyl starch (CMS) with succinic anhydride (SA) in the presenting of N, N-dimethylformamide (DMF) solvent and pyridine. The structure of the S-CMS was confirmed by spectroscopic techniques including proton nuclear magnetic resonance and Fourier transform infrared. The S-CMS crystallinity and thermal properties were checked by x-ray diffraction and thermogravimetric analysis. The results showed a decrease in thermal properties and crystallinity for S-CMS. The S-CMS were tested as adsorbents for the removal of phenol. The adsorption efficiencies of CMS, S-CMS1, S-CMS2, and S-CMS3 towards phenol were shown to be 0.297 g/g, 0.321 g/g, 0.322 g/g, and 0.324 g/g, respectively.

Polypyrrole nanotube/ferrocene-modified graphene oxide composites (PNT/GO-Fc, PNT/GO-Fc-GO, PNT/GO-EDA-Fc and PNT/GO-EDA-Fc-EDA-GO) were fabricated via in situ chemical oxidative polymerization. The prepared composites were characterized by FTIR, XRD, XPS, Raman, TGA, SEM, TEM and EDS. The electromagnetic interference shielding performance of the prepared composites was evaluated by a coaxial method within the frequency range of 1.0–4.5 GHz. The results demonstrated that the composite of PNT/GO-EDA-Fc-EDA-GO-7:1 exhibited the best electromagnetic interference shielding property with 28.73 dB (at the frequency of 1.0175 GHz with the thickness of 3.0 mm) of total shielding effectiveness by adding 50 wt% of the composite in the paraffin matrix. And the composite of PNT/GO-EDA-Fc-EDA-GO-7:1 exhibited good conductivity with a value of 1.320 S/cm. The relationship between the conductivities of prepared samples and the EMI shielding performance was investigated.

In recent years, polyolefin elastomers play an increasingly important role in industry. The late transition metal complex catalysts, especially α-diimine Ni(II) and α-diimine Pd(II) complex catalysts, are popular “chain-walking” catalysts. They can prepare polyolefin with various structures, ranging from linear configuration to highly branched configuration. Combining the “chain-walking” characteristic with different polymerization strategies, polyolefins with good elasticity can be obtained. Among them, olefin copolymer is a common way to produce polyolefin elastomers. For instance, strictly defined diblock or triblock copolymers with excellent elastic properties were synthesized by adding ethylene and α-olefin in sequence. As well as the incorporation of polar monomers may lead to some unexpected improvement. Chain shuttling polymerization can generate multiblock copolymers in one pot due to the interaction of the catalysts with chain shuttling agent. Furthermore, when regarding ethylene as the sole feedstock, owing to the “oscillation” of the ligands of the asymmetric catalysts, polymers with stereo-block structures can be generated. Generally, the elasticity of these polyolefins mainly comes from the alternately crystallineamorphous block structures, which is closely related to the characteristic of the catalytic system. To improve performance of the catalysts and develop excellent polyolefin elastomers, research on the catalytic mechanism is of great significance. Electron spin resonance (ESR), as a precise method to detect unpaired electron, can be applied to study transition metal active center. Therefore, the progress on the exploration of the valence and the proposed configuration of catalyst active center in the catalytic process by ESR is also reviewed.

Ferrocene (Fc)-based polymers have promising application in burning rate catalysts (BRCs) for solid composite propellants, and some of them have already been practically used. However, they have some drawbacks such as high migration during a long-time storage. Copolymers of poly(2-(methacryloyloxy) ethyl ferrocene carboxylate-co-glycidyl methacrylic acid)s (P(FHEMA-co-GMA)s) were synthesized to overcome the migration problem of Fc-based BRCs as well as to boost the burning rate (BR) of ammonium perchlorate (AP)-based propellants. The structures of the obtained P(FHEMA-co-GMA)s were confirmed by proton nuclear magnetic resonance (1H NMR) and Fourier transform infrared (FT-IR) spectroscopy. Cyclic voltammetry (CV) method was used to study their electrochemical behavior, and the P(FHEMA-co-GMA)s showed redox behavior for the existence of the Fc units. Because of the formation of integrated network structures, the P(FHEMA-co-GMA)s have good anti-migration performances. The BR catalytic property of P(FHEMA-co-GMA)s were investigated by thermogravimetry (TG) and differential thermogravimetry (DTG). They showed competent catalytic effects on the thermal decomposition of AP.

Succinylated starches (SS) were prepared by the reaction of normal starch (NS) and porous starch (PS) with succinic anhydride (SA) in the presence of DMF solvent and base pyridine, respectively. The proton nuclear magnetic resonance and Fourier transform infrared were used to confirm the successful synthesis of the SS (SS1, SS2, SS3 and SS4, respectively). The X-ray diffractometer XPert PRO (Cu Kα, λ = 1.54 A) was used to study the crystallinity of NS, PS and SS. The XRD analysis showed that the SS exhibited amorphous nature after succinylation. Thermogravimetric analysis and differential thermal analysis of NS, PS and SS showed that succinylation decreased the thermal stability. The morphology of the NS, PS and SS was studied by SEM. These SS were used as adsorbents for phenol removal. The adsorption efficiencies for phenol by NS, SS1, SS2, SS3 and SS4 were found to be 0.084 g/g, 0.165 g/g, 0.173 g/g, 0.183 g/g and 0.189 g/g, respectively.

The development of telecommunication instruments and electronic devices caused a number of subtle electromagnetic radiations, which have adverse effects on the equipment and especially the health of humans. To date, in order to reduce the harmful radiations, considerable attention has been given to the microwave absorbers due to their several attributes, such as cost-effectiveness, environmental stability and lightweight. Given that polyaniline possesses all above-mentioned properties, in this review, we mainly focus on preparation methods and application of polyaniline-based composites as microwave absorbers, including polyaniline/carbon material composites, polyaniline/magnetic material composites and polyaniline/carbon material/magnetic material composites, and the mechanisms of electromagnetic (EM) wave dissipation have also been discussed. The polyaniline-based composites are more efficient for microwave absorption due to their unique properties; therefore, they could be considered as good materials for microwave absorbers to hinder the EM radiations.

To overcome the migration problems of burning rate catalysts (BRCs), ferrocene-based amide compounds (AM-Fcs) were synthesized. The successful synthesis of AM-Fcs were confirmed by proton nuclear magnetic resonance, and Fourier transform infrared spectroscopy. The electrochemistry behaviors of AM-Fcs were examined by cyclic voltammetry (CV). The CV experimental results indicated that these AM-Fcs showed good electrochemical performances, which were contributable to their burning rate (BR) catalytic activity in composite solid propellants. The anti-migration test of AM-Fcs verified significantly slower migration than ferrocene and the most commonly used BRCs catocene. Thermal stability and BR catalytic impact of AM-Fcs on the thermal decomposition of ammonium perchlorate (AP) were studied by thermogravimetry and differential thermogravimetry. These AM-Fcs revealed good catalytic behaviors on the thermal degradation of AP.

In this study, poly(cyclotriphosphazene-co-piperazine) p(HCCP-co-PIP) nanospheres were prepared. The successful preparation of the p(HCCP-co-PIP) nanospheres was confirmed by FT-IR, SEM, TEM, XRD, ...

Among metals, AgNWs are considered to be excellent materials for use in surface enhancement Raman spectroscopic (SERS) sensing due to their superior electrical properties, strong electromagnetic field generation and strong enhancement intensity. Herein, we used a simple conventional polyol method to synthesize AgNWs feasibly in 40 min under Ar inert atmosphere without using any inorganic salts; only high molecular weight PVP was used as a capping and growth controlling agent, while ethylene glycol was used as a solvent as well as a reducing agent and silver nitrate was used as a Ag source. The polyol-synthesized smooth surface AgNWs were then subjected to chemical etching using aqueous ammonia and 30% hydrogen peroxide as etchant materials, and corrugated surface AgNWs were successfully prepared. The as-synthesized corrugated surface AgNWs were used as surface enhancement materials to increase the intensity of Raman signals, and the surface enhancement properties of the corrugated surface AgNWs were studied using rhodamine 6G as a probe molecule via SERS sensing. The results showed that the AgNWs were successfully prepared in 40 min of reaction; also, corrugated surface AgNWs were prepared, and their corrugated surfaces resulted in high intensity SERS signals.

Silver nanowires (AgNWs) with high uniformity and controlled morphology were synthesized by employing silver nitrate as precursor and ethylene glycol as reducing agent and solvent. Polyvinyl pyrrolidone (PVP) was used as growth controlling agent and the synthetic process was carried out in salt free environment. The effect of reaction parameters like concentration of AgNO3 and the reaction temperature on the final morphology of AgNWs was studied. AgNWs obtained by changing different conditions were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), high resolution transmission electron microscope (HRTEM), selected area electron diffraction pattern (SAED), X-ray diffraction (XRD) and UV–Vis spectroscopy. Synthesized AgNWs were coated on polyethylene terephthalate substrate by spin coating method to make thin conductive flexible film. The silver nanowires film was found to have a sheet resistance of 6.82 Ω/sq.

In this article, starch phosphate-g-poly (methacrylic acids) (SP-g-PMAAs) were synthesized by dual modification. Firstly starch phosphate (SP) was synthesized by phosphorylation of native starch (NS) with mono sodium-phosphate and di sodium-phosphate. Afterwards, methacrylic acid (MAA) was grafted onto SP via free radical polymerization to synthesize SP-g-PMAAs. The structure of the SP and SP-g-PMAAs was investigated by phosphorus nuclear magnetic resonance, proton nuclear magnetic resonance and fourier-transform infrared spectroscopy. The X-ray diffraction studies showed that the modification diminished the crystalline nature of SP and SP-g-PMAAs. The SEM images showed spherical or polyhedral smooth surface for the starch. After modification, SP and SP-g-PMAAs exhibited distorted and rougher surfaces which are assumed to be good for adsorption. The dual modification produced phosphate and carboxylic groups on the starch backbone. The phosphate and carboxylic groups have high tendency to make hydrogen bonding with phenol. The comparative adsorption studies of NS, SP and SP-g-PMAAs were checked for phenol. The experimental results showed adsorption efficiencies of 0.022 g/g, 0.082 g/g, 0.100 g/g, 0.148 g/g and 0.151 g/g for NS, SP, SP-g-PMAA1, SP-g-PMAA2 and SP-g-PMAA3, respectively. The following findings revealed that dual modification enhanced the adsorption ability of NS.

Ferrocene-based polypyrrole (PPyFc) composites containing multi-walled carbon nanotube (MWCNT), reduced graphene oxide (RGO) and carbon black (CB) have been prepared by chemical oxidative polymerization. The prepared PPyFc/MWCNT, PPyFc/RGO and PPyFc/CB composites have been characterized by SEM, TEM, FTIR, XRD, XPS and TGA. Electrical conductivity of the PPyFc/MWCNT, PPyFc/RGO and PPyFc/CB composites has been tested by a typical four-probe method. Furthermore, the electromagnetic interference shielding effectiveness (EMI SE) of the PPyFc/CB, PPyFc/RGO and PPyFc/MWCNT composites has been measured through a coaxial method in the S-band frequency range. The EMI SE achieved for PPyFc/CB, PPyFc/RGO and PPyFc/MWCNT composites was − 11.08 dB, − 11.44 dB and − 23.74 dB, respectively.

Biofouling is one of the major worldwide problems associated with the vessel due to its accumulation with the surface of the ship hull. The biofouling is the main origin of the coating’s deterioration that ultimately leads to bio-corrosion, roughness and drag, resulting in an enormous increase in the fuel consumption. Although Tributyltin (TBT) has been used as a pioneer class of antifoulant to overcome this problem, however, after the legal restriction on TBT, some biocides have been used as its alternatives. These biocides are potentially harmful to the environment due to the higher release rate in the aquatic environment. This review paper focuses on the progress made in eco-friendly antifouling coating techniques, using control biocide release principal for marine application. The three main strategies, hydrophilic, hydrophobic, and biodegradable antifouling coating, are reviewed. Biodegradable antifouling coating is a new promising route based on the combination of eco-friendly biocide with dynamic surfaces by utilizing degradable polyurethane, polyester acrylate, and modified polyester based polymers. They are used as a carrier of antifoulant, which control the release rate and also show excellent antifouling activity in the marine coatings due to tunability, sustainability, and mechanical performance, therefore, they have a longer shelf period. Moreover, this review focuses on the challenges associated with vessel surface coating and their possible solutions.

Different hydrogels of poly(acrylamide-co-3-acrylamido phenylboronic acid-co-chitosan grafted maleic acid) (P(AM-co-AAPBA-co-CSMA)s) were synthesized using poly(ethylene glycol) diacrylate (PEGDA) as a crosslinker to serve for glucose sensing and insulin delivery. The structure and morphology of the hydrogels, named as CSPBA were studied by FTIR and SEM, while the mechanical properties were tested using dynamic mechanical analysis (DMA) and universal testing machine. The prepared hydrogels shrinked at low glucose concentration due to the 2:1 boronate-glucose binding, and swelled at high glucose concentration because of 1:1 boronate-glucose complexation. Both binding mechanisms are useful for glucose sensing and insulin delivery. The integration of CSMA into hydrogels network not only enhanced the response to glucose at physiological pH, but also improved the mechanical properties and increased the encapsulation efficiency of the prepared hydrogels. These CSPBA may find potential as implantable hydrogels in applications were continuous glucose monitoring and controlled release is beneficial.

The colonization of tiny marine organisms on ship's hull which are connected directly from seawater, is a costly issue. Biofouling contributes to enhanced hydrodynamic drag, which leads to higher consumption of fuel and greenhouse gas emissions. Therefore, the environment-friendly solution is very necessary for anti-biofouling activity. For this purpose, we have synthesized biodegradable polyurethane (CL-PU) composed of e-CL and 4,4′-methylenebis(cyclohexyl isocyanate) (H12MDI) and 1,4 butanediol (1,4 BD). The synthesized CL-PU was further modified with 4, 5-dicholoro-2-octyl-isothiazolone (DCOIT) and clay by mixing of the solution to make composites. Our study showed that CL-PU/DCOIT/clay composite degraded in the artificial seawater (ASW), enzymatic solution and seawater (through laboratory test) due to the contents of clay. Because the existence of clay reduced the size of the spherulite of polycaprolactone (PCL) in the composite, therefore remarkably improved the crystallinity as determined via the polarizing optical microscope (POM) and differential scanning calorimetry (DSC). The composite acted as carrier of antifoulant (DCOIT) and controlled their release rate. The anti-bacterial and anti-diatom experiments exhibited that the composite with DCOIT contents were effective in preventing the accretion of Escherichia coli (E.coli) (region inhibition 14 mm) and marine diatom Navicula incerta (82.5% reduction). The degradable CL-PU/DCOIT/clay composite will have tremendous durability and excellent anti-fouling activity for marine biofouling owning to sustainability and tunability without being toxic to aquatic biota.

Silver nanowires (AgNWs) have attracted growing interest because of their wide range of applications in modern nano electronic appliances. During polyol method, the presence of cations and anions in the reaction solution has influence on the final morphology of AgNWs. Here we report a feasible way to prepare AgNWs by polyol method. Copper bromide (CuBr2) salt was used to provide anions and cations in the reaction solution. The anions (Br−) helps in reducing the amount of free Ag+ by forming silver bromide (AgBr) during initial silver seeds formation and the cations scavenge oxygen from the surface of AgNWs during preferential growth of the AgNWs. Ethylene glycol (EG) was used as a solvent and reducing agent, silver nitrate (AgNO3) was used as Ag source and polyvinyl pyrrolidone (PVP) was used as a capping agent. The effects of various factors which influence the final morphology of AgNWs were studied. AgNWs were successfully synthesized in the presence of CuBr2 salt. The morphology of the synthesized AgNWs was characterized by the SEM and TEM. The crystallinity was characterized by HRTEM, SAED and XRD. The LSPR peaks of Ag nanostructures were revealed by UV–Vis spectroscopy. The conductive properties of AgNWs thin conductive films were studied by coating the synthesized nanowires on polyethylene terephthalate (PET) substrate.

Starch is a homopolysaccharide made up of glucose units which are linked together via a glycosidic linkage. This biopolymer is well known for its low cost, biodegradability, renewability and easy availability. In spite of all these beauties, starch has some problems with their solubility in water, retrogradation, loss of viscosity due to rupturing of glucosidic bond when subjected to treatment and absence of some groups of primary importance like different functional groups especially carboxylic group, ester group, ether group and amino group. In order to overcome these shortcomings and enhance its applications, starch must be modified. The modification can be done chemically, physically and enzymatically, but noteworthy one is the chemical modification. In this review article, we focused on the recently used ways of chemical modification such as acid hydrolysis, cross-linking, acetylation/esterification, dual modification, oxidation and grafting of starch, and their properties. This review article highlighted the application of modified starch as an adsorbent for the removal of ammonia, phenol, heavy metals, and dyes.

Cigarette industry plays an important role in the economy of the advanced countries. But the cigarette smoke contains toxic chemicals such as phenol which causes various kind of diseases and affect human life. In this paper, we synthesized carboxymethyl starch grafted poly vinyl imidazole (CMS-g-PVIs) by reacting carboxymehtyl starch (CMS) with vinyl imidazole (VI). The structures of the CMS-g-PVIs were investigated by 1H NMR and FT-IR. The crystalline properties of the CMS and CMS-g-PVIs were checked by XRD. The thermal properties of the original CMS and CMS-g-PVIs were investigated by TGA analysis. It was found that the modified starches had high thermal stability due to aromatic imidazole ring. The modified starches also showed more rough and distorted morphology as compared to native CMS. The CMS-g-PVIs were subjected for phenol adsorption and showed adsorption efficiencies of 0.170 g/g, 0.190 g/g, 0.192 g/g and 0.199 g/g for CMS, CMS-g-PVI 1, CMS-g-PVI 2 and CMS-g-PVI 3, respectively. Due to higher grafting ratio, CMS-g-PVI 3 showed good adsorption efficiency of 0.199 g/g for phenol. The obtained results showed that the grafting of vinyl imidazole on CMS can increase the adsorption efficiency of native CMS towards phenol.

Efficient composite solid propellants possess stable burning rate (BR) and low-pressure exponents. To achieve the ideal performance of propellants, addition of burning rate catalysts (BRC) to the propellants system is one of the best choice. BRC are of tremendous notable significance in composite propellants for their distinctive feature to positively enhance the operational efficiency of solid propellants. In this regard, many valuable kinds of BRC have been synthesized. Due to their better ignitability, ferrocene-based compounds are well-known class of BRC. However, considerable migration and diffusion tendency of this developed class of useful compounds during storage procedures of composite solid propellants limit their practical use as an ideal BRC. This article reviews recent advances in the active field of Fc-based derivatives. In gradual addition, this article also highlights recent progress of Fc-based derivatives as a BRCs and adequately discuss their significant improvements in anti-migration properties.

In this study carboxymethyl starch grafted poly(methacrylic acids) (CMS-g-PMAAs) were synthesized by treating carboxymethyl starch with methacrylic acid in the presence of initiator potassium persulfate (KPS). The modified starches were characterized by proton nuclear magnetic resonance (1H NMR) and fourier-transform infrared (FT-IR) spectroscopy. The crystallinity of the modified starches was analyzed by x-ray diffraction (XRD) while thermal properties of the modified starches were found out by thermogravimetric analysis (TGA) and differential thermal analysis (DTG). These modified starches were then tested as an adsorbent for the removal of ammonia and phenol from the gaseous mixture. The maximum adsorption efficiencies of CMS, CMS-g-PMAA1, CMS-g-PMAA2, and CMS-g-PMAA3 for ammonia were 0.005, 0.020, 0.023 and 0.031 g/g respectively. Similarly, for phenol, the maximum adsorption efficiencies of CMS, CMS-g-PMAA1, CMS-g-PMAA2 and CMS-g-PMAA3 were shown to be 0.2085, 0.2445, 0.2473 and 0.2501 g/g respectively. It was shown that CMS-g-PMAAs could be used as an additive in cigarette filters to remove the toxicant ammonia and phenol from cigarette smoke.