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A new accepter unit, 2,3-didodecyl-6,7-difluoroquinoxaline, was prepared and utilized for the synthesis of electron acceptor–donor–acceptor materials for organic solar cells. 2,3-Didodecyl-6,7-difl...

In this study, we focused on the manufacturing of void-free composites of electrospun nylon 6 nanofibers as reinforcement for the poly(vinyl alcohol) (PVA) matrix. PVA solution was introduced into ...

A simple modification of cellulose nanocrystals (CNC) was intended for preparing ameliorated nanofillers for UV-curable PUA coatings. This modification was carried out by dispersing CNC in DMSO wit...

The control of surface wettability through a combination of surface roughness, chemical composition, and structural modification has attracted significant attention for antifogging and antibacterial applications. Herein, a two-step spin-coating method for amphiphilic organic-inorganic hybrid materials with incorporated transition metal ions is presented. The coating solution was prepared via photochemical thiol-ene click reaction between the mercapto functional group in trimethylolpropane tris(3-mercaptopropionate) and the vinyl functionalized silica precursor 3-(trimethoxysilyl)propyl methacrylate. In the first step of coating, a glass substrate was coated using a solution of metal nitrate hydrates and subsequently showed hydrophobic properties. As the second step, the spin-coated glass substrate was further coated with silica nanoparticles (SiO2 NPs) and polycaprolactone triol (PCT) suspension, where the contents of SiO2 NPs were fixed at 0.1 wt %, unless otherwise noted. The coated substrate exhibited hydrophilic properties. For comparison, the coating was also formulated with the SiO2 NPs/PCT suspension without SiO2 NPs and with 0.5 wt % SiO2 NPs as well as by adjusting different coating layer thicknesses. The surface morphology and chemical compositions of the obtained coating materials were analyzed by field emission scanning electron microscopy with energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. The transparency and static contact angle of coated samples were measured by UV-visible spectrophotometry and drop shape analysis, respectively. It was concluded that our novel hybrid coating materials exhibited excellent antibacterial and antifogging properties with extremely high scratch resistance and transparency.

A series of novel structured latex particles with semi-interpenetrating polymer network (IPN) of glassy styrene-acrylonitrile copolymer (SAN) cores and rubbery polyurethane (PU) shells were synthes...

Since a production line for 3D printing is easier to change a product model than that for traditional manufacturing one, 3D printing technology is developing and growing faster than most other tech...

Recently, conventional solvent-typed polyurethanes are subject to many regulations due to emission of organic volatile compounds(VOCs) and researches have been focused on eco-friendly waterborne po...

The degradability of degradable polymers is the most important property to determine the lifetime of commercial applications. To control degradation rate and thermal properties, enantiomeric block ...

Although a photo curing is more efficient in terms of time, solvent, and cost than a thermal one, photo-curable coatings require low viscosity and fast curing speed due to workability and time savi...

Over the past few years, silicone-based polymers have been widely studied because silicone shows unique surface properties, such as hydrophobicity, film formability, etc and then silicone-based com...

We designed and synthesized two novel low band gap small molecule donors (M1 and M2) that consist of benzo[1,2-b:4,5-b′]dithiophene as the electron-rich core and 6,7-difluoroquinoxaline as the elec...

Synthesis of zeolitic materials with coal fly ash (CFA) using a fusion/hydrothermal method was performed by various crystallization parameters such as aging time, crystallization time, crystallizat...

Since most of the coatings have been prepared by organic solvents, there are many regulations because of the environmental and health hazards caused by volatile organic compounds. As an alt...

Polyurethane- and polysiloxane-based coating agents are widely used in automobiles and electronic devices for sealing. To study a component which affects their surface properties, polyureth...

Polyurethane is one of the most versatile polymeric materials and is found just about everywhere in modern life including coatings and adhesives in electronics and automobile interior. Howe...

In order to develop ultraviolet (UV)-curable coatings applicable to pre-coated metal (PCM), organic-inorganic hybrid UV curable polyurethane (PU)-acrylates were prepared using cage type met...

Polyaspartic coating is well known as one of popular eco-friendly coatings because of non VOC and excellent mechanical properties such as fast curing, abrasion resistance, chemical resistan...

Typical light stabilizers absorb and block UV rays in the wavelength range of 300-380 nm region. This range overlaps with the UV region, necessary to cure UV-curable coating. By overlapping...

Magnetic nanoparticles containing mesoporous carbon materials have been synthesized via an one-pot strategy associated with a direct carbonization process from resol, metal ion sources (Co(...

The value of the critical surface tension(γc.0) of the polyolefin part calculated by Zismann plot was 26.1 dyne/cm. The surface state and the γc,0 of the polyolefin part were changed by sol...

A new type of UV-curable organic–inorganic hybrid oligomer was synthesized from vinyltrimethoxysilane (VTMS), tetraethylorthosilicate, and colloidal silica (CS) using a sol–gel method. UV-curable hybrid hard coating formulations were then prepared by mixing the organic–inorganic hybrid oligomer and acrylic monomers, trimethylolpropane triacrylate and tetrahydrofurfuryl acrylate, with a levelling agent and a photoinitiator. The oligomer was hydrolyzed and condensed from alkoxysilane and CS to obtain the UV-cured hybrid films. The hybrid oligomer and resulting hybrid films were characterized by Fourier transform infrared spectroscopy, 29Si nuclear magnetic resonance spectroscopy, scanning electron microscopy, and ultraviolet–visible spectrophotometry to confirm the chemical functionality, oxo-silicon signal, cross-sectional morphology, and transparency, respectively. When the concentration of the CS/VTMS mixture in the organic–inorganic hybrid oligomer was 0.50 mol, remarkable pencil hardness (up to 5H) with excellent transparency was observed. The hardness and transparency of the UV-cured hybrid coating films were improved significantly by increasing the CS content in the organic–inorganic hybrid oligomer.

To develop environmentally friendly coating materials with good workability, a low-viscosity polyurethane acrylate (LPUA) was newly synthesized using cycloaliphatic isocyanate, 2-hydroxypropyl acrylate and caprolactone hydroxyl acrylate. Low-viscosity UV-curable dendritic polyurethane acrylate coatings (LPUA-DAs) were then prepared by adding different amounts of dendritic acrylates to LPUA. The viscosity of the resulting products, curing behavior, mechanical and thermal stability, hardness, and flexibility of the UV-cured films were examined. The mechanical properties and the glass transition temperature increased with increasing content of dendritic acrylates but the viscosity decreased. The optimal properties of the coating materials were observed when 10% of dendritic acrylate was used.

To develop a halogen-free polyurethane adhesive for thermoplastic nonpolar polyolefins, polyurethanes were synthesized by using polyester polyol, polyolefin polyol, 4,4′-dicyclohexylmethane diisocy...

Eco-friendly water-repellent UV-curable polyurethane acrylates (PUA) with fluorine groups were synthesized from H12MDI which is excellent yellowing resistance and water resistance, polycarbonate di...

The UV-curable coatings are emerging as new environmental friendly coating technology for replacement of solvent-based ones. UV-curable polyurethane acrylate oligomers were newly synthesized using ...

In this study, chloroprene rubber (CR) /silica nanocomposites prepared by dispersing nanosilica in CR was applied as a primer and its adhesion properties were examined. The structure of CR/silica n...

For an environmentally-friendly coating, waterborne UV-curable poly-urethane acrylates were synthesized with different mixing ratios of 4,4-methylene dicyclohexyl diisocyanate (H12MDI) and ...

To expand their applications, UV-curable coatings for pre-coated metal (PCM) require high flexibility and stiffness for formability and hardness, respectively. However, it is difficult to satisfy b...

Although polyurethane (PU)- and polysiloxane-based coating agents find wide applications in electronics and automotive industries (e.g., for sealing), their full potential can be realized only base...

Poly(lactic acid)(PLA)/lipophilized graphene oxide (LGO) nanohybrids were prepared using a solution blending method. Graphene oxide (GO) was synthesized using a modified Hummers method and then lipophilized by functionalization with alkylamines such as octylamine (OA), dodecylamine (DA), or octadecylamine (ODA). The PLA/GO (PG) nanohybrids were also prepared for comparison. Among the LGOs, ODA-GO was chosen to produce the PLA/LGO (PLG) nanohybrids because ODA-GO exhibited obvious intercalation behavior and the best dispersibility in chloroform. The properties of the PGs and PLGs were examined by scanning electron microscopy, wide-angle X-ray diffraction, differential scanning calorimetry, thermogravimetric analysis, universal testing machine, chemical resistance test, and hydrolytic degradable analysis. The hydrophobic ODA-GO (LGO) was dispersed on the nanoscale within the PLA matrix and the resulting nanohybrids showed significantly higher chemical resistance and reduced hydrolytic degradation.

Among the curing hardeners for powder coating, β-hydroxyalkylamide is widely used due to its easy handling, excellent exterior durability, good mixing with other chemicals, flexibility, hardness, a...

To improve the mechanical and thermal properties of polyurethane, two prepolymers, polyurethane acrylate (PUA) and epoxy acrylate (EPA) which have acrylate-ended groups, were synthesized. The obtained prepolymers were homogeneously mixed with various compositions and cured by UV. After UV curing, the properties of PU/EP copolymers were investigated by using Fourier-transform infrared spectroscopy, universal testing machine, dynamic mechanical thermal analysis and thermogravimetric analysis. The thermal and tensile properties of PU/EP copolymers gradually increased with the amount of EP due to the intermolecular interaction whereas their elongation properties decreased. These results indicate that the copolymerization of PU with EP could control their mechanical properties.

We prepared novel hybrid materials by in situ self-hydroxylation and condensation of polymethylsiloxane (PMHS) with multi-walled carbon nanotubes (MWCNTs). The hybrid material showed superhydrophobic and non-stick properties, mesoporous structure, and liquid marble-like non-stick water droplet behavior. Moreover, we found that the in situ addition of MWCNTs to the PMHS would increase the thermal stability of the hybrid material. Thermal stability of the hybrid is enhanced by increasing the percentage of MWCNTs to the PMHS. The superhydrophobic hybrid powder covered non-stick water droplet showed anti-icing behavior for long time. The hybrids also showed oils sorption behavior and easy reusable property. The obtained results suggest that the thermally stable superhydrophobic hybrid mesoporous materials with anti-icing, oils sorption properties can be easily synthesized and used for various applications.

The hybrid material of magnetic graphene oxide (MNPs/GO) was prepared with a facile route and adsorption properties for removal of methylene blue (MB) were investigated. Initially, the surface of m...

In this study, poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV)/graphene oxide (GO) nanocomposite films containing various content of GO were prepared using solution casting method. The effect of GO content on Young`s modulus and dispersion of GO in PHBV matrix was investigated. Also, the thermomechanical properties, oxygen transmission rates and hydrolytic degradation of PHBV/GO nanocomposite films were studied. The addition of GO into PHBV improves the Young`s modulus and decreases thermal expansion coefficient. The improvement can be mainly attributed to good dispersion of GO and interfacial interactions between PHBV and GO. Furthermore, PHBV/GO nanocomposite films show good oxygen barrier properties. PHBV/GO nanocomposites show lower hydrolytic degradation rates with increasing content of GO.

In this study, low bandgap polymers containing a monofluoroquinoxaline (FQx) or a difluoroquinoxaline (DFQx) as the electron-deficient unit and 2-thiophenylbenzo[1,2-b:4,5-b']dithiophene as the electron-rich unit were synthesized by Stille polymerization. The polymers exhibit satisfactory thermal stability and a broad absorption band from 300 to 650 nm. The HOMO/LUMO energy levels of PB-FQx and PB-DFQx were − 5.62/− 3.64 and − 5.70/− 3.63 eV, respectively. We found that for a high number of fluorine atoms in the conjugated backbone, the HOMO energy levels were deeper, which led to increased VOC. The PB-DFQx:ITIC-based PSC exhibited the best power conversion efficiency of 6.31%, with its VOC of 0.99 V, JSC of 10.61 mA/cm2, FF of 60%.

Two type of triblock copolymers [poly(l-lactide)-b-perfluoro polyether-b-poly(l-lactide) (fluoro l-PLA) and poly(d-lactide)-b-perfluoro polyether-b-poly(d-lactide) (fluoro d-PLA)] (fluoro PLAs) were synthesized by ring-opening polymerization. The synthesized triblock copolymers showed more hydrophobic properties than pristine l-PLA due to the perfluoro polyether (PFPE). To control the surface properties, the blends were prepared by mixing fluoro PLAs with l-PLA. The degradation rates of the fluoro PLAs/l-PLA blends were retarded due to the surface segregation of PFPE which has lower surface energy. In case of the fluoro d-PLA/l-PLA blends, however, the stereocomplex formation between the l-lactide and d-lactide sequences enhanced the thermal and enzymatic stabilities of l-PLA. As a result, the biodegradability of l-PLA can be controlled by copolymerization or the formation of a stereocomplex.