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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.

Hypothesis Organic radical polymers with tailored pendant functionalities have emerged as exciting and promising materials for their application versatility. Moreover, eco-friendly polymer-based organic nanomaterials with redox-active pendant side groups can replace the harmful heavy metal-based inorganic materials. On the other hand, self-assembled nanomaterials are of great interest and attracted more attention recently for their promising application in different advanced fields, but it is yet challenging to predict suitable hydrophilic-lipophilic balance (HLB) for stimuli-responsive random copolymers assembly due to structural irregularity. Among several experimental techniques, electron paramagnetic resonance (EPR) spectroscopy plays a unique and promising role in revealing structural and dynamic information of nanostructured radical containing materials. Experiments In this study, a series of spin labeled amphiphilic random copolymers poly(methyl methacrylate-co-acrylic acid) have been synthesized and characterized by FT-IR, UV–Vis spectroscopies, TGA, DSC and water contact angle (CA) techniques. Their electrochemical properties have been determined by cyclic voltammetry (CV) in different organic solvents. EPR spectroscopy has been applied with other analytical techniques to elucidate the smart supramolecular nanoparticles (SNPs) formation, stimuli-responsiveness and structural changes through the dynamics of different molecular interactions. Findings The structural and dynamic information of self-assembled nanoparticles have been observed to be dependent on multiple-stimuli-responsiveness in different microenvironments by applying physiological and chemical parameters such as the different concentration of radicals, pH, temperature, nature of the solvent and reducing agent. The obtained results reveal the knowledge to understand insight into the mechanism for the formation of stimuli-responsive colloidal nanoparticles assembled from amphiphilic random copolymers with apt HLB value. The CV results reveal that the charge transfer process of the nanoparticles in solution was diffusion regulated and depended on the accessibility of radicals. The radical (spin labeled) polymers offer a broad way to develop stimuli-responsive materials in various colloidal nanostructures by changing the microenvironment, appreciating their potential advanced applications in electronic devices, catalysis, stimuli-triggered drug/gene delivery and reactive oxygen species (ROS) scavenger.

High molecular weight polyvinylpyrrolidone (PVP) and seeding conditions are considered to have important roles in the synthesis of AgNWs. In this work, we report a versatile synthesis of AgNWs in a salt-free environment and under Ar inert atmosphere using high molecular weight PVP and seeding step during the synthetic process. The high molecular weight PVP was found to efficiently promote the preparation of AgNWs via supporting the proper growth control of AgNWs on {111} facets and selective growth on {100} facets. The seeding step facilitates the formation of seeds such as multiple twinned nanoparticles (MTPs) and single crystal seeds, which promoted the feasible formation of AgNWs. The shape and size of the synthesized AgNWs were characterized by SEM and TEM. The crystalline nature of the synthesized AgNWs was characterized by HRTEM, SAED and XRD, and their LSPR peaks were confirmed by UV-Vis spectroscopy. The conductive properties of the synthesized AgNWs were determined by preparing their thin conductive film on a PET substrate. The prepared AgNWs thin films exhibited good sheet resistance.

Shape memory polymers (SMPs), as a class of intelligent materials, have shown great potential in biomedical and robotic fields. Although efforts have been made to design and fabricate SMPs in the p...

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.

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.

The review article encompasses an overview of the contemporary research related to an arsenal of smart materials i.e., shape memory hydrogels (SMHs). SMHs are instrumental in fixing temporary shapes or recovering permanent ones in response to external stimuli and are playing an increasingly important role in a diverse range of applications including soft robots, artificial mussels, embolic agents and so forth. As cynosure of smart materials, SMHs have attracted considerable attention in recent years owing to their unique functionality. We highlighted the mechanism of the shape memory effect (SME) and the design principle of SMHs coupled with recent advances in four distinct classes of SMHs where SME is triggered in response to temperature, pH, chemicals, and light. Besides, the progress in biomedical applications of SMHs has also been presented.

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.

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.