MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2020
·Vol. 221
·期 7
·1900540
·
IF 2.335
Yin Zhang,Huayi Li,Zhi Luo,Mengru Li,Tingting Liu,Weiwei Liu,Qian Li,Youliang Hu
A novel macromolecular auxiliary antioxidant with polyethylene (PE) as polymer skeleton and phosphites as side groups is prepared based on commercial ethylene-vinyl acetate (EVA) copolymers and its potential as polyolefin stabilizers is studied in depth. The synthesis approach of this PE-grafted antioxidant consists of a typical EVA hydrolysis reaction and a two-step nucleophilic substitution reaction of PCl 3 , 2,4-di-tert-butylphenol, and the hydrolysis product. Results of the thermogravimetric analysis show that the macromolecular structures endow the as-synthesized antioxidant with much better thermal stability than that of the commercial antioxidant 168. In addition, antioxidant behaviors of the PE-grafted antioxidants in polypropylene (PP) matrix are investigated in detail through characterization of the melt flow index of multiple-extruded stabilized PP as well as the short-term oxidation induction time test and the long-term thermo-oxidative aging test. Results show that even with extremely low content of the effective antioxidant groups, the as-synthesized macromolecular antioxidant still has excellent antioxygenic properties.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
NANOTECHNOLOGY
·
2022
·Vol. 33
·期 50
·505602
·
IF 3.953
Fan Fang,Haochen Liu,Zuoliang Wen,Chenxi Liu,Bing Xu,Zhikuan Zhang,Kai Wang,Mehmet Ertugrul,Wei Lei,Xiao Wei Sun
Colloidal quantum dots (QDs) are promising luminescent materials for display and lighting, but their stability has long been an issue. Here, we designed a passivation strategy of doping Ti ions into the shell of alloyed CdZnSeS@ZnS QDs. The results showed that Ti ions were successfully doped into the ZnS shell and the stability of QDs was improved. In the aging test, the Ti ions doped QDs maintained 51.4% of the initial performance after 90 h of aging, while the pristine QDs decreased to less than 25% of the initial value. In addition, we discuss the reasons why Ti ions doping improves the stability of QDs. Ti ions are found to form Ti–S bonds in the ZnS shell, which has high binding energy and strong oxidation resistance. Most importantly, since there is no external physical insulating coating, the optimized QDs can also be directly used in electroluminescent devices, showing great potential in electroluminescence applications.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Polymers
·
2023
·Vol. 15
·期 13
·2835
·
IF 5
Yijuan Chang,Zhihui Wu
This study aimed to investigate the impact of different sandpaper sanding meshes on the mechanical and optical properties of microencapsulatedTiliasp. film. An orthogonal experiment revealed that sanding between primers had the most significant effect. Furthermore, an independent experiment implied that increasing the mesh size resulted in decreased surface roughness and decreased color difference, elongation at break, and gloss after liquid resistance. In the aging test, the color difference of the paint film increased with the aging time, and the gloss tended to stabilize. Additionally, the anti-aging gloss of 240 mesh sandpaper used between primers remained relatively stable. The paint film sanded with 240 mesh sandpaper between primers displayed small and regular cracks after temperature and UV aging. Overall, the paint film demonstrated good comprehensive performance when sanded with 240 mesh between primers, 240 mesh between primer/topcoat, and 1000 mesh for topcoat. Self-repairing microcapsules showed better repair efficacy on the coating. This study provides a technical reference for the development of self-repairing coatings.
研究领域:
材料科学
·
涂层技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
NORDIC PULP & PAPER RESEARCH JOURNAL
·
2022
·Vol. 37
·期 2
·311-319
·
IF 1.595
Zhenzhen Chen,Yingping Qi,Yongfeng Shen,Hua Li
As the main carrier of art and cultural heritages, paper cultural relics are suffering from aging, oxidation, acidification, bacterial corrosion and other diseases with the passage of storage time. Therefore, it is of great significance to carry out the protection of paper cultural relics. In order to improve the bacteriostatic properties, mechanical strength and delay aging of paper, sodium carboxymethyl cellulose was modified by berberine and prepare berberylated carboxymethyl cellulose (BBR-DCMC), which is mixed with KH-791 modified nano-silica and hydroxypropyl distarch phosphate to prepare a multifunctional protective liquid integrating deacidification, reinforcement and antibacterial. The paper coated with the multifunctional protective liquid showed better antibacterial and mechanical properties, and the gloss and whiteness changed slightly. The aging test and the acid and alkali resistance test showed that the paper had certain aging resistance and acid and alkali corrosion resistance. It is an ideal protective agent for paper cultural relics and has broad application prospects in paper protection.
研究领域:
文物保护
·
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2018
·Vol. 135
·期 25
·46385
·
IF 1.901
Huibin Lei,Deliang He,Yanni Guo,Yining Tang,Yao Lu
Several kinds of free-radical-catching fluorine–silicone acrylic resins with different contents of 2,2,6,6-tetramethyl-4-piperidyl methacrylate (TMPM) were synthesized by solution copolymerization. The chemical structures and properties of the resins were characterized and followed the performances of their respective coatings. The results demonstrate that these kinds of resins showed a high ability to produce nitroxide. The coatings had good thermal stability and hydrophobicity with water contact angles over 100°. Moreover, the weather resistance showed a great improvement for the synergetic protection by bonded TMPM, organic fluorine, and silicone. By aging tests, the modified coatings still maintained excellent mechanical properties with an impact strength and flexibility of 400 N cm and 2 mm, respectively. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135 , 46385.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
Heritage Science
·
2024
·Vol. 12
·期 1
·1-16
·
IF 2.6
Xie Lina,Li Yuhu,Hu Wenjing,Fang Shiqiang,Chen Xue-Qiang
Damage and fracture of archaeological potteries not only jeopardize the long-term preservation but also hinder their exhibition. To repair these pottery sherds effectively, this study introduces a novel inorganic phosphate-based adhesive and evaluates its effectiveness through a series of experiments. To determine the optimal base adhesive, the paper investigates the influence of varying weight ratios of the H 2 O–H 3 PO 4 system and the Al(OH) 3 –H 3 PO 4 system on properties including tensile lap-shear strength, microstructure, high-temperature resistance and phase composition. However, the original black color of the traditional CuO–phosphate adhesive limits its application. The innovation of this study lies in the addition of nano-TiO 2 to the adhesive, which not only improves the bonding strength but also adjusts the color of the adhesive. This study has defined the optimal formulation (i.e., base adhesive = m[Al(OH) 3 ]:m[H 3 PO 4 ] = 7:100, filler = 10wt% nano-TiO 2 ), and the final product shows no residual acid in adhesives. Additionally, the fracture surfaces are successfully bonded with a high strength of 3.56 MPa. Various ageing tests including dry-thermal ageing, hygrothermal ageing and UV irradiation ageing are conducted to assess the ageing resistance of the inorganic phosphate-based adhesive. The results indicate strong tolerance of adhesive to high temperature and high humidity environment. Preliminary applications in archaeological pottery restoration suggest that the inorganic phosphate-based adhesive offers considerable promise for repairing shattered pottery. Graphical Abstract
研究领域:
考古学
·
材料科学
·
文物保护
✓ 已验证
产品关联
DOI
高影响因子
POLYMER SCIENCE SERIES B
·
2022
·Vol. 64
·期 4
·402-410
·
IF 1.023
Xubo Huang,Fan Junwei,Liu Zhaogang,Zhao Jingang,Chen Mingguang,Hu Yanhong,Wu Jinxiu
Abstract Rare earth thermal stabilizers are a kind of newly discovered stabilizers, which are considered as a series of very promising stabilizers for inhibiting the degradation of PVC in the application and processing. Therefore, the continued exploration of new rare earth heat stabilizer is very necessary for scientific research and practical application. In this work, a new rare earth thermal stabilizer lanthanum cerium 6-methyluracil (LCMUA) was successfully synthesized via using cerium nitrate, lanthanum nitrate, 6-methyluracil (MUA) and aqueous ammonia as raw materials. And it was characterized by elemental analysis, FTIR, TG and other methods, the molecular formula of lanthanum cerium 6-methyluracil is confirmed as: La 0.35 Ce 0.65 (C 5 H 4 N 2 O 2 )NO 3 ⋅2H 2 O. Subsequently, congo red tests and thermal aging tests of pristine LCMUA and LCMUA with calcium stearate (CaSt 2 ), zinc stearate (ZnSt 2 ), and pentaerythritol (PE) composite samples were performed, when LCMUA/CaSt 2 /PE is compounded with mass ratio of 3 : 1 : 1, the heat stabilization time reached 70 min, and the heat stabilization performance was the best, which is better compared to those of commercial CaSt 2 and ZnSt 2 . The excellent experimental results can be attributed to the special absorption effect of LCMUA for hydrogen chloride gas derived from the thermal decomposition of PVC, thereby removing in time hydrogen chloride gas to restrain the PVC self-decomposition process caused by HCl gas.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 15
·8608-8619
·
IF 3.049
Qi Chu,Ling Lin
The effect of molecular flexibility on the rheological and filtration properties of synthetic polymers used as fluid loss additives in water-based drilling fluid was investigated. A new synthetic polymer (PAANS) comprising acrylamide (AM), 2-acrylamido-2-methyl-1-propane sulfonic acid (AMPS), N-vinyl-2-pyrrolidone (NVP) and potassium 2,5-dihydroxybenzenesulfonate (DHBS) was synthesized, in which phenyl groups were introduced in the backbone. Two other comparative polymers, PAAN and PAANS, were also prepared following the same synthesis procedure. PAAN comprises AM, AMPS and NVP, while PAANS consists of AM, AMPS, NVP and sodium 4-styrenesulfonate (SSS). PAAN, PAAND and PAANS were characterized by 1H NMR and elemental analysis, and the molecular weight was determined by static light scattering (SLS). The rheological properties, filtration properties and performance sustainability were investigated. Using a rheological properties measurement test, the apparent viscosity (AV), plastic viscosity (PV) and yield point (YP) of the Na-MMT/PAAND system at a concentration of 2.0% were 18.0 mP s, 12.0 mP s and 6.0 Pa, respectively, after a thermal aging test at 240 °C for 16 h. These values are much higher than those of the corresponding Na-MMT/PAAN and Na-MMT/PAANS systems. The API filtration loss volume (FLAPI) and high-temperature/high-pressure filtrate volume (FLHTHP) of the Na-MMT/PAAND system at a concentration of 2.0% were 12.0 mL and 30.0 mL, respectively, after a thermal aging test at 240 °C for 16 h. These values are much lower than those of the Na-MMT/PAAN and Na-MMT/PAANS systems. Compared with PAAN and PAANS, PAAND presents the best performance sustainability after multiple shearing and thermal aging tests. At the same temperature, the order of maintaining rheological performance and controlling the FLAPI and FLHTHP was PAAND > PAANS > PAAN in Na-MMT/PAANS-based drilling fluid at high temperature. Increasing the percentage of rigid monomers in the backbone was found to be conducive to maintaining the rheological stability and improving the filtration properties at high temperature. The control mechanism of fluid loss was investigated through adsorption tests using the method of thermal filtration, assessing particle size distribution on a laser diffraction particle size analyzer (LPSA) and examining filter cake morphologies using an environmental scanning electron microscope (ESEM). The results reveal that the introduction of rigid monomers into the synthetic polymer backbone can effectively improve the adsorption capacity of the polymer on the clay surface, obstruct the aggregation of clay particles, and improve the quality of filter cakes at high temperatures.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2018
·
IF 2.955
Fei Rao,Yuhe Chen,Xiping Zhao,Hanjiang Cai,Neng Li,Yongjie Bao
Benzotriazole (BTZ), benzophenone (BP), nano-TiO 2 (NTiO 2 ), and nano-ZnO (NZnO) are potential components of UV protection coatings due to being UV light absorbers. Herein, the UV-protective effects of four acrylic coatings containing individual organic and inorganic UV light absorbers and another four coatings containing both types of absorbers were determined by employing accelerated bamboo aging tests. Although organic absorbers decomposed during aging, their degradation rate decreased in the presence of inorganic absorbers. Moreover, individual organic absorbers were better suited for color stabilization than inorganic ones, with the best bamboo surface photostability enhancement achieved by BTZ-containing coatings (BTZ, BTZ-NZnO, and BTZ-NTiO 2 ). Furthermore, strong synergistic effects were detected for BTZ-NZnO and BTZ-NTiO 2 , whereas an antagonistic effect was observed for BP-NTiO 2 and BP-NZnO. Thus, combinations of organic and inorganic UV light absorbers efficiently inhibited the degradation of the former, with the performance of clear coatings determined by the type of the organic absorber.
研究领域:
材料科学
·
林业科学
✓ 已验证
产品关联
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2015
·
IF 2.358
Ling Yang,Shuxue Zhou,Limin Wu
Titania/poly(methyl methacrylate) core/shell (TiO 2 /PMMA) latex was synthesized by miniemulsion polymerization and further mixed with modified colloidal silica to create waterborne nanocomposite coatings (M-SiO 2 /TiO 2 /PMMA). The coatings were undergone accelerated weathering tests and their surface wettability, transparency, and morphology were monitored as a function of weathering time. Superhydrophilic surfaces were attained after 27–34 h aging, being attributed to the unique distribution of TiO 2 nanoparticles in PMMA phase. In contrast to the coating based on the mixture of M-SiO 2 , TiO 2 nanoparticles, and PMMA latex, this time is quite short and absolutely benefit for their outdoor application. Due to the degradation of organic matrix, transparency reduction and film thickness loss of coatings took place in weathering tests. Nevertheless, these undesired evolutions can be alleviated by decreasing film thickness or using adequate quantity of TiO 2 /PMMA latex. Photodegradation experiments of methyl blue indicate that the formed superhydrophilic coatings are excellent in self-cleaning performance.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
·
2023
·Vol. 24
·期 9
·7882
·
IF 5.6
Biao Yang,Xinbo Yang,Yuchuan Li,Siping Pang
Exposure to ultraviolet (UV) light is known to cause skin aging, skin damage, cancer, and eye diseases, as well as polymer material aging. Therefore, significant attention has been devoted to the research and development of UV absorbers. Considering the robust hydrogen bonding and conjugated structure present in nitrogen-containing polycyclic compounds, these compounds have been selected as potential candidates for exploring ultraviolet absorption properties. After structural optimization and the simulation of ultraviolet absorption spectra, four tris-[1,2,4]-triazolo-[1,3,5]-triazine (TTTs) derivatives, namely TTTB, TTTD, TTTJ, and TTTL, were selected as the preferred compounds and synthesized. The structure of the compound was determined using various analytical techniques, including FTIR,1HNMR,13CNMR, HRMS, and XRD. Subsequently, composite films of polyvinyl chloride (PVC) and TTTs were produced using a simple solvent casting technique. The PVC films were subjected to UV age testing by exposing them to an ultraviolet aging chamber. The age-resistant performance of the fabricated films was evaluated using an ultraviolet spectrophotometer and Fourier infrared spectrum instrument. The findings suggest that TTTs exhibit a noteworthy capacity for absorbing ultraviolet radiation. The TTTL compound exhibits a superior UV absorption performance compared to commercially available UV absorbers such as UV-0 and UV-327 in the market.
研究领域:
材料科学
·
有机化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Bio-Design and Manufacturing
·
2024
·
IF 8.1
Li Linze,Jiang Changqing,Li Luming
导电聚合物涂层以其优异的电化学性能，在神经电极领域受到广泛关注。其中，聚（3,4-乙烯二氧噻吩）：聚（苯乙烯磺酸）（PEDOT:PSS）是一个典型的代表。然而，这些导电聚合物涂层对铂铱等常用电极材料的附着力弱，严重制约了其实际应用。为了克服这一挑战，本研究探索了利用飞秒激光制备层级铂铱基底来增强PEDOT:PSS涂层的粘附稳定性。通过重复循环伏安测试和加速老化测试，评价光滑铂铱和层级铂铱基底上滴铸及电化学沉积两种方式制备的PEDOT:PSS涂层的稳定性。结果表明，经过2000次重复循环伏安扫描或在60 °C下老化五周后，层级铂铱基底表面的涂层形貌和电化学性能保持相对稳定；相比之下，光滑铂铱基底表面的PEDOT:PSS涂层出现了分层、开裂，并表现出电荷存储能力的降低和阻抗的升高。综上，采用飞秒激光制备层级结构可以显著增强铂铱神经电极表面PEDOT:PSS涂层的稳定性，这为提高电极电化学性能、开发多模态神经电极提供了巨大的潜力。
研究领域:
材料科学
·
神经科学
·
电化学
·
生物医学工程
✓ 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）