Effect of sol maturation on the preparation of luminescent ormosils

Abstract

An UV-polymerization approach was proposed to construct luminescence organic-inorganic hybrid. Methacryloxypropyltrimethoxysilane (MAPTMS) was chosen as sol-gel precursor to prepare the host matrix and acrylic europium Eu(AA) 3 was used as guest dopants. Structural modifications during irradiation were evident in both the inorganic and organic domains of the hybrid material. The influence of condensation degree of the silicate network on the photopolymerization kinetics of organic moieties was investigated. It appeared that the sol maturation time was of vital importance to the phase homogeneity and optical transparency of materials. To get more efficient copolymerization and higher luminescence intensity of the target ormosils, two key processing factors including incorporation time and entrapping concentration are reported. Incorporation time when acrylic europium was introduced into the matrix during sol maturation is found to be helpful to overcome phase separation. The effect of entrapping concentration of europium(III) compound on the luminescence performance was further studied. Material synthesized by this approach has three advantages: optical transparency with little phase separation, organic and inorganic composite with interpenetrating network, covalent grafting of acrylic europium without luminescent species leakage. This "photopolymerization of molecular grafting" strategy is hopeful to offer a promising development for luminescent ormosil glasses.

Noncovalent functionalization of carbon nanotubes using branched random copolymer for improvement of thermal conductivity and mechanical properties of epoxy thermosets

“…12(a), which results in a decrease in interfacial interaction between fillers and matrix and a deterioration in mechanical properties. 30,38 In contrast, the fracture surfaces for composites filled with CNTs/BPHNV become coarser, and stress whitened zones could also be observed. This indicates that a crack deflection process occurred, where an initial crack tilted and twisted when it encountered a rigid inclusion.…”

“…Previous literature showed that carbazole group could ensure strong -interaction with CNTs. 30 Furthermore, Liu et al 29 reported that branched polymers have more advantages in dispersing CNTs for their attractive features such as the highly branched structure, multiple end groups, improved solubility, lower solution viscosity and three-dimensional globular structure. Here we take it that because of the special structure and carbazole groups existing in NVCz units, BPHNV could favorably adhere to the surface of CNTs through -stacking interaction, serving as an intermediate layer and inhibiting tube-tube contacts and bundle formation, further promoting the dispersion of CNTs.…”

“…The impact strength of neat epoxy is about 13 kJ mol −1 , which slightly decreases when MWCNTs are added, which may be attributed to the defects between fillers and matrix. 30 However, it is noted that there is a significant enhancement in impact strength when CNTs/BPHNV is incorporated in the epoxy resin, and the highest toughness, corresponding to an enhancement of approximately 130%, appears when BPHNV loading rises to 1.0 wt%. Similarly, the tensile strength behaves in a favorable manner for EP/CNTs/BPHNV composites.…”

A Dual-Wavelength Phosphorescent Anti-Counterfeiting Copolymer Containing Eu(III) and Tb(III)

“…Some rare earth ions show pure luminescent characteristics of fixed wavelength and narrow emission, high color purity and good color saturation due to the 4 f electron being shielded by the 5 s 2 5 p 6 electron, becoming the first choice of luminescent center of anti-counterfeiting materials [ 10 , 11 , 12 ]. The bonded rare earth polymer phosphors have both excellent luminescent performance of a rare earth complex and good film forming performance of a polymer [ 13 , 14 , 15 , 16 , 17 , 18 ], which has become a research focus of anti-counterfeiting ink.…”

3-Glycidoxypropyltrimethoxysilan: Description, and Analysis of Works Approaches and Applications

“…Remove the requirement for a priming in polysulfide & urethane sealants. Enhance the adherence of aqueous acrylic sealants, as well as urethane & epoxy coatings[76,77,78,79,80]]. depicts the GPTMS FTIR spectrum.…”