JOURNAL OF NANOPARTICLE RESEARCH
·
2017
·Vol. 19
·期 7
·1-10
·
IF 2.02
He Xiaoyan,Wang Meng,Zhang Caiyun,Liu Liqin
An ultraviolet shielding hydrogel of P(NaSS-co-MPTC)/TiO 2 was prepared by introducing TiO 2 nanoparticles (TiO 2 NPS) into polyampholyte matrix through photo-initiated radical copolymerization of cationic monomer of 3-(methacrylamide) propyltrimethylammonium chloride (MPTC) and anionic monomer of sodium 4-vinylbenzenesulfonate (NaSS) in the aqueous solution of sodium chloride (NaCl). FTIR, XPS, TEM, XRD, and SEM were used to characterize the morphology and structure of hydrogel of P(NaSS-co-MPTC)/TiO 2. The result showed that anatase TiO 2 NPS with the size about 15 ~ 20 nm were not just acted as ultraviolet shielding agent and general photo-initiator, they also could be crosslinked in polyampholyte matrix by hydrogen bonding between hydroxyl groups on the surface of TiO 2 NPS and sulfonate groups on the polymer chains. Based on two kinds of reversible weak bonds of hydrogen bond and ionic bond, the P(NaSS-co-MPTC)/TiO 2 hydrogel exhibited excellent mechanical properties and self-healing ability at ambient conditions, which will greatly increase its service life being a UV inhibitor.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF PHYSICAL CHEMISTRY B
·
2017
·
IF 3.177
Yang Wang,Chennong Xiang,Ting Li,Piming Ma,Huiyu Bai,Yi Xie,Mingqing Chen,Weifu Dong
In this article, PVA composites with outstanding thermal stability, UV shielding, and high transparency were fabricated on the basis of traditional Chinese medicine (esculetin). Characterization data have suggested in which the resulting PVA/esculetin (ESC) composites display excellent thermal stability compared to pure PVA and most of the PVA nanocomposites. The pyrolysis mechanism of PVA before and after modification with esculetin varies from chain unzipping degradation followed by chain random scission. The DPPH scavenging activity and FTIR measurements have illustrated that esculetin can scavenge reactive radicals, which leads to improvements in thermal stability and a change in the pyrolysis mechanism of PVA. More importantly, the resulting composites can almost completely block the whole UV region (200–400 nm) without any deterioration of the high transparency of the composites. Therefore, the composites can convert harmful UV light into blue light effectively, which is beneficial for their application as optical materials and devices.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FIRE AND MATERIALS
·
2017
·Vol. 42
·期 1
·99-108
·
IF 1.352
Xiaomeng Wang,Xueqing Liu,Sha Peng,Panrui Peng,Liyong Zou,Jia Chen,Jiyan Liu
Summary A novel phosphorus-containing acrylate monomer (AOPA) was synthesized starting from 2-methy-2,5-dioxo-1,2-oxaphospholane and hydroxyethyl acrylate. The structure of AOPA was characterized with FTIR and 1 H NMR. AOPA shows good compatibility with polyethylene glycol diacrylate (PEGDA) and can polymerize with PEGDA under UV light irradiation at different mass ratios to form membranes with high transparency (above 88.9% of light transmittance in the range of 400-800 nm) and flexibility. Incorporating 20 wt% of AOPA in PEGDA reduced the total heat release and peak rate by 50.3% and 38.4%, respectively, as measured by micro combustion calorimeter. The membrane containing 40 wt% of AOPA with 0.4 mm thickness can pass the UL94 V0 rating, and limiting oxygen index reaches 33.4%. TG-FTIR and SEM-EDX analysis show that the presence of AOPA depresses the thermal degradation and promotes the char formation.
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS & DESIGN
·
2016
·
IF 3.997
Qiong Tian,Demei Yu
Interfacial adhesion between fillers and matrix is important to the properties of their composites. In this study, hollow and solid polymer microspheres/epoxy composite films were prepared via powder mixing method and UV-curable polymerization. Interfacial adhesion was established by chemical bonding among the epoxy groups of the microspheres and epoxy matrix . The tensile strength and modulus of polymer microspheres/epoxy composite films first increased and then decreased with increasing the content of fillers. The specific tensile strength and modulus of hollow microspheres/epoxy composites were higher than those of solid microspheres/epoxy composites. The fracture mode of the composite films changed from crack of the polymer microspheres to interfacial debonding with increasing the filler's content . Characteristics of shear yielding deformation, particle bridging and crack bowing mechanisms were identified from the microscopic image of tensile fracture surfaces . The improvement of tensile properties compared with neat epoxy resin was discussed on the basis of percolation mechanism. The hollow polymer microspheres/epoxy syntactic foam films retained high electrical resistivity and UV-shielding property. The UV-curable hollow polymer microspheres/epoxy syntactic foam films with good strength could be used as electrical insulating materials.
✓ 已验证
产品关联
DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2015
·Vol. 27
·期 7
·882-888
·
IF 1.757
Mehdi Derradji,Noureddine Ramdani,Lin-dan Gong,Jun Wang,Xiao-dong Xu,Zai-wen Lin,Abdelkhalek Henniche,Wen-bin Liu
In the present work, zinc oxide nanoparticles were treated with aminopropyl trimethoxy silane-coupling agent and used as a new kind of reinforcement for a typical high performance bisphenol-A-based phthalonitrile resin. The resulted nanocomposites were characterized for their mechanical, thermal, and optical properties. Results from the tensile test indicated that the tensile strength and modulus as well as the toughness state of the matrix were all enhanced with the increasing of the nanoparticles amount. Thermogravimetric analysis showed that the starting decomposition temperatures and the residual weight at 800°C were highly improved upon adding the nanofillers. At 6 wt% nanoloading, the glass transition temperature and the storage modulus were considerably enhanced reaching about 359°C and 3.7 GPa, respectively. The optical tests revealed that the neat resin possesses excellent UV-shielding properties, which were further enhanced by adding the nanofillers. Furthermore, the fractured surfaces of the nanocomposites analyzed by scanning electron microscope exhibited homogeneous and rougher surfaces compared with that of the pristine resin. Finally, the good dispersion of the reinforcing phase into the matrix was confirmed by a high resolution transmission electron microscope. Copyright © 2015 John Wiley & Sons, Ltd.
✓ 已验证
产品关联
DOI
高影响因子
COLLOID AND POLYMER SCIENCE
·
2017
·Vol. 295
·期 2
·371-378
·
IF 1.723
Wang Youpeng,Li Guo,Cheng Ruidong,Zhang Xuan,Jiang Jinqiang
Amphiphilic random copolymer micelle of P(NVP- co -NHPM) that responds to both UV and NIR light was designed and investigated. N -hydroxyphthalimide methacrylate — bearing a photoacid generator functional group was synthesized and used to construct the hydrophobic segment of P(NVP- co -NHPM); the N–O bond can be photocleaved when exposing the polymer aqueous solution to 310 nm UV light irradiation, inducing the micellar dissociation and delivery of loaded substances. Dynamic light scattering (DLS), atomic force microscope (AFM), and transmission electron microscopy (TEM) were used to characterize the micellar dissociation and controlled release processes. Moreover, the upconverting nanoparticles (NaLuF 4 :Gd/Yb/Tm) that can effectively absorb NIR light and convert it into visible and UV light were coloaded into polymer micelles to activate the micellar dissociation and the delivery of loaded cargoes via 980 nm NIR light.
✓ 已验证
产品关联
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2017
·
IF 3.169
Xiong Xu,Jianying Yu,Canlin Zhang,Zhilong Cao,Yi Gu,Lihui Xue
This paper mainly investigates the effect of the reactive rejuvenator diphenyl methane diisocyanate (MDI) and 1,4-butanediol diglycidyl ether (BUDGE) on chemical structures of aged SBS and rejuvenated structures, rejuvenation mechanisms, physical and rheological properties of UV-aged SBS modified bitumen (SMB). Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) show the hydroxyl and carbonyl groups have formed on aged SBS, which indicates that the broken-chain structures of SBS have formed after UV radiation. Meanwhile, the disappeared hydroxyl groups and formed amide bond in FTIR spectrum of MDI rejuvenated SBS, and the associated hydroxyl groups and another appeared carbonyl groups in FTIR spectrum of BUDGE rejuvenated SBS indicate MDI and BUDGE can act as a “bridge” to connect the broken-chain SBS together at 150 °C. Moreover, the performance results show rejuvenation temperature and time have little impact on the physical properties of rejuvenated SMB whatever the rejuvenator is selected. With the increasing content of MDI, the softening point of rejuvenated SMB can be improved and the ductility at low temperature remains almost unchanged. However, the softening point of rejuvenated SMB decreases and the ductility increases as the rising content of BUDGE. Phase angle results indicate MDI can further increase the elasticity of aged SMB, and BUDGE can to some extent restore the viscosity characteristic. From the results of fatigue and rutting performance, 1% BUDGE weakens the fatigue limit temperature of aged SMB from 20.1 °C to 14.9 °C and 1% MDI increases the rutting limit temperature from 79.6 °C to at least 80 °C, which indicates BUDGE and MDI can respectively help improve the fatigue resistance and rutting resistance. Based on the analysis of FTIR spectra and the relative functional group indexes, the results show the increasing concentration of I NH CO in MDI rejuvenated SMB and I C O C in BUDGE rejuvenated SMB, indicating the chemical reaction between reactive rejuvenators and aged SMB can be occurred. The rejuvenation of aged SMB with MDI or BUDGE abides by the addition reaction mechanism or condensation reaction mechanism.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2012
·Vol. 128
·期 6
·4261-4270
·
IF 1.289
Wensong Han,Baoping Lin,Hong Yang,Xueqin Zhang
First, the second-generation hyperbranched poly(amine-ester) (G2-OH) was successfully prepared by thiol-ene “click” chemistry. Subsequently, a series of photosensitive hyperbranched oligomers (G2-ORs) were synthesized by facile modifications of the G2-OH with acryloyl chloride, methacryloyl chloride, IPDI-HEA, and IPDI-HEMA, respectively. The structures of hyperbranched oligomers were characterized by element analysis, FT-IR, 1 H NMR, GPC and viscosity measurement. It was shown that these synthesized oligomers have narrow molecular weight distribution and low intrinsic viscosity at 30°C. UV–vis spectra results showed that the G2-ORs had sharp absorption bands at around 202 nm. The results of photosensitivities measurement indicated that the G2-Macr shows the highest photosensitive than other hyperbranched oligomers in the absence of photoinitiator. In addition, these UV-cured photosensitive G2-ORs had good thermal properties. The solubilities of the synthesized hyperbranched oligomers were also examined. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
✓ 已验证
产品关联
DOI
高影响因子
CHROMATOGRAPHIA
·
2015
·Vol. 78
·期 11
·833-837
·
IF 1.411
Zhang Mingyu,Qiu Danye,Kang Jingwu
A simple, sensitive and environmentally friendly capillary electrophoresis method for the determination of free sulfate anions in heparin and low-molecular-weight heparin with indirect UV detection is reported. The background electrolyte consists of 20 mM nitrate (pH 5.5) containing 0.2 mM CTAB. The use of nitrate as the probe anion is based on the consideration that nitrate has a very close electrophoretic mobility to that of sulfate, leading to a very narrow peak shape. Moreover, the apparent molar absorptivity of nitrate at 202 nm (8413 L mol −1 cm −1 ) is much higher than that of the commonly used probe anion chromate at 254 nm (2400 L mol −1 cm −1 ). The combination of the narrow peak shape with the high apparent molar absorptivity of the probe ion improved the limit of detection by 2.4 times and the limit of quantitation by 3.2 times. The effect of various CE parameters on the separation of sulfate from chloride was investigated and optimized. The method displays linearity in the range from 0.05 to 20 mM. The RSD % for intraday ( n = 6), and interday ( n = 3) repeatability in terms of migration times and peak areas were all less than 3 %. The limit of detection ( S / N = 3) and limit of quantitation ( S / N = 10) for sulfate were determined as 18 and 53 µM, respectively. The method was successfully applied for the quantification of sulfate anions in heparin and low-molecular-weight heparins.
✓ 已验证
产品关联
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2013
·
IF 1.848
Ren Liu,Jiajia Zhu,Jing Luo,Xiaoya Liu
With a view to developing high performance UV curable coatings with high renewable contents, acrylated epoxidized soybean oil (AESO) was combined with a novel kind of biorenewable tannic acid-based hyperbranched methacrylates (TAHAs). The TAHAs were synthesized by ring-opening reaction of glycidyl methacrylate (GMA), glycidyl ester of Versatic acid (CE10) and natural tannic acid (TA). The epoxy groups of GMA and CE10 were involved in the ring-opening reaction with the hydroxyl groups of TA while residual methacrylate groups can carry out photopolymerization . By controlling the ratio of GMA and CE10, TAHAs with varying degree of methacrylate groups have been prepared. The synthesized TAHAs were formulated into acrylated epoxidized soybean oil (AESO) based UV curable coatings to produce the biorenewable materials based UV curable coatings. The effects of TAHAs on AESO coated film properties of pendulum hardness, flexibility and adhesion were investigated. Mechanical properties , thermal properties and biodegradability of the cured films were also evaluated. With the incorporation of TAHAs, the hardness, adhesion, tensile strength of the cured coating films were remarkably improved, which were attributed to the unique structure of hyperbranched methacrylates. Meanwhile, the biorenewable content was not greatly decreased due to the biorenewable character of tannic acid in TAHAs. These results showed that TAHAs as efficient toughening agents could produce UV-curable coatings of balanced coating performance with reasonably high biorenewable content. Moreover, the environment degradability of AESO-based cured films was also enhanced after the addition of TAHAs.
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2014
·
IF 5.9
Jianzhong Du,Hui Sun
Presented in this paper is a hybrid polymer/titanium dioxide (TiO2) vesicle that has excellent UV-screening efficacy and strong capacity to encapsulate antioxidant agents. Poly(ethylene oxide)-block-poly(2-(dimethylamino)ethyl methacrylate)-block-polystyrene (PEO-b-PDMAEMA-b-PS) triblock terpolymer was synthesized by atom transfer radical polymerization (ATRP) and then self-assembled into vesicles. Those vesicles showed excellent UV-screening property due to the scattering by vesicles and the absorption by PS vesicle membrane. The selective deposition of solvophobic tetrabutyl titanate in the PDMAEMA shell and the PS membrane of the vesicles led to the formation of polymer/TiO2 hybrid vesicles, resulting in an enhanced UV-screening property by further reflecting and scattering UV radiation. The vesicles can effectively encapsulate antioxidant agents such as ferulic acid (up to 57%), showing a rapid antioxidant capability (within 1 min) and a long-lasting antioxidant effect.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Coatings Technology and Research
·
2017
·Vol. 14
·期 6
·1325-1334
·
IF 1.557
Liu Jingcheng,Wang Kuan,Xie Yazhen,Gao Fei,Zeng Qingtao,Yuan Yan,Liu Ren,Liu Xiaoya
A series of novel partially bio-based fluorinated polyimides with double-bond end groups (BGPIs) from 4,4′-(hexafluoroisopropylidene) diphthalic anhydride, 4,4′-(hexafluoroisopropylidene) dianiline, Priamine 1074, 4-aminobenzoic acid, and glycidyl methacrylate were synthesized via a copolycondensation method in m -cresol. The chemical structure and performances of BGPIs were fully characterized by Fourier transform infrared spectroscopy, proton nuclear magnetic resonance, gel permeation chromatography, solubility test, X-ray diffraction, and differential scanning calorimetry. It was determined that the prepared BGPIs were in the amorphous phase and readily soluble in conventional aprotic polar solvents. Additionally, the properties of as-prepared UV-cured coatings based on BGPIs were also evaluated by real-time Fourier transform infrared, thermogravimetric analysis, UV–Vis spectroscopy, and so on. Results revealed that all coatings exhibited satisfactory curing, higher adhesion, lower water uptakes, outstanding optical transparency, and fairly favorable thermal stability under a high content of biomass up to 48.9%. Therefore, these bio-based polymers could be considered as a potential sustainable candidate for high-temperature UV-curable coatings in the microelectronic field.
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）