Puig, Julieta; Zucchi, Ileana A.; Ceolín, Marcelo; Schroeder, Walter F.; Williams, Roberto J. J.
Evolution of morphologies of a PE-b-PEO block copolymer in an epoxy solvent induced by polymerization followed by crystallization-driven self-assembly of PE blocks during cooling
Polymerization-induced nanostructuration combined with crystallization-driven self-assembly was used to generate complex nanostructures in an epoxy network. A PE-b-PEO block copolymer (Mn = 1400; 50 wt% PEO), was dispersed in diglycidylether of bisphenol A (DGEBA) and homopolymerization initiated by a tertiary amine was carried out at 120 °C (above the melting…
Facile method for the synthesis of Fe3O4@HCP core–shell porous magnetic microspheres for fast separation of organic dyes from aqueous solution
Pan, Long; Xu, Meng-Ying; Liu, Zi-Lu; Du, Bi-Bai; Yang, Kun-Hao; Wu, Li; He, Peng; He, Yu-Jian
A novel type of porous magnetic microsphere (Fe3O4@HCP) was firstly synthesized just via one-step Friedel–Crafts alkylation promoted by FeCl3. This universal and facile method to fabricate porous magnetic microspheres possesses distinct advantages such as cheap reactants, mild reaction conditions, a short reaction time and a simple post-treatment process. The core–shell…
Fast response and highly sensitive humidity sensors based on CaCl2-doped sulfonated poly (ether ether ketone)s
Zhuang, Zhuang; Qi, Duo; Ru, Chunyu; Pan, Jing; Zhao, Chengji; Na, Hui
This study presented a novel polymeric humidity sensor based on CaCl2-doped sulfonated poly (ether ether ketone) (SPEEK). For the first time, we developed a crosslinking procedure to modify SPEEK for humidity sensors application. SPEEKs with fixed value of sulfonation degree were synthesized by a direct aromatic nucleophilic substitution polymerization of…
Fluorescent silica nanoparticles with chemically reactive surface: Controlling spatial distribution in one-step synthesis
Vera, María L.; Cánneva, Antonela; Huck-Iriart, Cristián; Requejo, Felix G.; Gonzalez, Mónica C.; Dell’Arciprete, María L.; Calvo, Alejandra
The encapsulation of fluorescent dyes inside silica nanoparticles is advantageous to improve their quality as probes. Inside the particle, the fluorophore is protected from the external conditions and its main emission parameters remains unchanged even in the presence of quenchers. On the other hand, the amine-functionalized nanoparticle surface enables a…
Formation of a transient amorphous solid in low density aqueous charged sphere suspensions
Niu, Ran; Heidt, Sabrina; Sreij, Ramsia; Dekker, Riande I.; Hofmann, Maximilian; Palberg, Thomas
Colloidal glasses formed from hard spheres, nearly hard spheres, ellipsoids and platelets or their attractive variants, have been studied in great detail. Complementing and constraining theoretical approaches and simulations, the many different types of model systems have significantly advanced our understanding of the glass transition in general. Despite their early…
Formation of hydrogels based on chitosan/alginate for the delivery of lysozyme and their antibacterial activity
Wu, Tiantian; Huang, Jiaqi; Jiang, Yangyang; Hu, Yaqin; Ye, Xingqian; Liu, Donghong; Chen, Jianchu
Novel hydrogels based on chitosan/sodium alginate (CS-ALG) were prepared to deliver and protect lysozyme while eliminating food-borne microorganisms. These hydrogels were characterized according to the zeta potential, optical microscopy, scanning electron microscopy (SEM), UV–visible spectroscopy (UV–vis), fourier transform infrared (FT-IR), and small-angle X-ray scattering (SAXS). The results…
From solvent-cast to annealed and poled poly(VDF-co-TrFE) films: New insights on the defective ferroelectric phase
Bargain, François; Panine, Pierre; Domingues Dos Santos, Fabrice; Tencé-Girault, Sylvie
Films of ferroelectric vinylidene fluoride-trifluoroethylene copolymers, poly(VDF-co-TrFE), are investigated for future applications in organic electronics. For these developments, a composition ∼70 mol % VDF is selected, thin and isotropic films are evaporated, then annealing and poling steps are performed to increase the amount of ferroelectric phase. Over the past decades, many…
Functional liquid crystalline gels through multi-scale hierarchical self-assembly of LAPONITE® and amidodiol
Narayanan, Rohini Kuttiplavil; Sadanandhan, Neethu Kalloor; Sasi, Renjith; Devaki, Sudha Janardhanan
Herein we demonstrate the design and synthesis of liquid crystalline gels through multi-scale hierarchical self-assembly of LAPONITE® and amidodiol in water. These two components interact with each other through non-covalent interactions, such as hydrogen bonding and ion–dipole interactions, to form highly ordered superstructures in different dimensions and length scales. Effects…
Gold nanoparticle stabilization within tailored cubic mesoporous silica: Optimizing alcohol oxidation activity
Hong, Wei; Yan, Xiaoqing; Li, Renhong; Fan, Jie
Stabilizing gold nanoparticles (AuNPs) within a desired size range is critical to realize their promising catalytic performance in many important reactions. Herein, we investigate the anti-sintering properties of cubic mesoporous silica (FDU-12) as a function of pore entrance size. Simple adjustments to the type of organic template and reaction temperature…
Hierarchical microstructure changes and the molecular mechanism of polypropylene under a critical failure strain during creep
Jia, Chenfei; Zhang, Qiongwen; Liao, Xia; Zhu, Jingjun; Wu, Lingyun; Ni, Kai; Yang, Qi; An, Zhu; Li, Guangxian
The hierarchical microstructure evolution of polypropylene during creep was explored via various methods, such as differential scanning calorimetry (DSC), scanning electron microscope (SEM), two-dimensional small-angle X-ray scattering (2D-SAXS), two-dimensional wide angle X-ray diffraction (2D-WAXD) and positron annihilation lifetime spectroscopy (PALS). The results revealed a correlation among…