Journal of Applied Biomaterials & Functional Materials
·
2020
·
IF 2
Xue Xia,Rui Shi,Jinhui Huang,Yubao Li,Yi Zuo,Jidong Li
The aim of the current study is to alleviate the adverse effect of the strongly exothermic polymerization of polymethyl methacrylate (PMMA) bone cement in clinical applications. In this study, paraffin/poly(methyl methacrylate–methylene bisacrylamide) (paraffin/P(MMA-MBA)) phase change microcapsules (MPn; n = 1, 2) were developed via the emulsion polymerization method. The reduction of the maximum temperature of polymerization (Tmax) and physicochemical properties were evaluated after doping commercial PMMA cement with MPn in specific proportions (10%, 20%, and 30%). The results reveal that the MPn-doped PMMA exhibited an effective reduction in Tmax, which can help alleviate the adverse effect of the strong exothermic reactions during PMMA setting. After doping with the MPn, the mechanical properties of the PMMA cement decrease and the values are close to that of body cancellous bone. The Tmax of the cement doped with 20 wt% MP1 is 37.6°C, which is close to body temperature. Significantly, the setting and compressive properties of the optimized group can still adhere to clinical requirements. The MPn doping PMMA technique holds much promise in clinical practice.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Physical Chemistry C
·
2015
·
IF 4.772
Bin Chen,Jiachun Feng
A white-light-emitting polymer composite film was designed and synthesized by using carbon dots (CDs) and lanthanide complexes as primary light emitters and skillfully embedding them into a poly(methyl methacrylate) (PMMA) matrix. The hydrophilic CDs used as blue light source were prepared and functionalized by copolymerizing with methacrylate to prevent their aggregate in the hydrophobic matrix. The lanthanide complexes Eu(DBM)3 and Tb(DBM)3 (DBM: dibenzoylmethide), in which the rare earth ions have not been fully coordinated, were fabricated and used as red and green emitters. The coordinatively unsaturated lanthanide ions could further coordinate with the oxygen atoms in the PMMA chains, which makes the complexes homogeneously dispersed in matrix as well as benefits to the energy transfer process. By adjusting the ratio of CDs, Eu(DBM)3 and Tb(DBM)3 in the matrix, the high transparent film with improved thermal stability, which prepared by a simple solution cast method, could emit pure white light (CIE coordinate located at (0.31, 0.32)) under 400 nm laser with a quantum efficiency of 16.6%. The energy transfer mechanism in the white-light-emitting material was also discussed.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER JOURNAL
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2016
·Vol. 49
·期 2
·263-271
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IF 1.629
Li Weiwei,Jiang Xue,Wu Ronglan,Wang Wei
We report a study on synthesizing fast, recoverable polyurethane/montmorillonite–poly(methyl methacrylate) (PU/MMT–PMMA) composites and understanding the influence of the grafting ratio of PMMA on the shape memory effect. PMMA was grafted on an exfoliated MMT surface via surface-initiated atom-transfer radical polymerization, which rendered a homogeneous dispersal of MMT in the PU matrix. The morphology and structure of the composites were characterized by scanning electron microscopy, transmission electron microscopy and powder X-ray diffraction. The mechanical, thermal and shape memory properties were characterized by dynamic mechanic analysis and temperature-modulated differential scanning calorimetry. Both tensile strength and strain at break for the composites increased with the introduction of MMT–PMMA, exhibiting 35 and 44% higher strength and strain than those of pure PU, respectively. The PU/MMT–PMMA composites showed high performance on shape memory behavior, with a shape fixity ratio of 100% and a shape recovery ratio of 99% in the first shape memory cycle. The composites also presented a higher shape recovery speed than both PU and PU/MMT. The best performance was obtained with a grafting ratio=3, with a recovery rate of 21.1° per second at 60 °C.
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
Journal of Cleaner Production
·
2019
·
IF 6.395
Jianchao Wang,Hui Wang,Dongbei Yue
This study provides a novel method, Fenton oxidation combined with flotation, to facilitate separation of waste polymethyl methacrylate and polyvinyl chloride mixtures for recycling. Fenton oxidation was found to induce selective surface hydrophilization of polymethyl methacrylate and suppress its flotation recovery in flotation, thereby facilitating its flotation separation with polyvinyl chloride. The surface hydrophilization occurred on polymethyl methacrylate surface was confirmed by the contact angle that decreased from 95.80° to 73.11°, and was attributed to the changes in surface hydrophilic groups and morphology. Scanning electron microscopy images revealed the formation of uniformly micrometer-scale spotted-structures on polymethyl methacrylate surface. X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy ascertained the obvious increase of elemental ratio of O/C and the introduction of hydrophilic groups (carbonyl and hydroxyl). The optimized conditions obtained for separation of polymethyl methacrylate and polyvinyl chloride mixtures were [H 2 O 2 ]/[Fe 2+ ] ratio of 3000, hydrogen peroxide concentration of 0.2 M, reaction time of 6.0 min, pH of 5.80, reaction temperature of 25.0 °C, flotation time of 3.0 min, frother dosage of 14.8 mg/L, and airflow rate of 6.0 mL/min. Under optimized conditions, for the samples with particle size of 0.9–4.0 mm, the recovery and the purity of polyvinyl chloride were 100% and 97.61%, and the recovery and the purity of polymethyl methacrylate were 97.55% and 100%, respectively. Particularly for the particle size of 3.2–4.0 mm, the purity and recovery of polyvinyl chloride and polymethyl methacrylate all reached up to 100%. Reusing of Fenton and flotation solutions was evaluated, and results indicated they can be used at least 3 and 5 times, respectively. Besides, a simple economic analysis demonstrated that this method is economically feasible. In conclusion, this environmentally friendly, sustainable, and economically feasible method contributes to improve the recycling quality of waste plastics, and provides technological insights in the cleaner and sustainable disposal of waste plastics.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULES
·
2012
·
IF 5.167
Weichao Shi,Xu-Ming Xie,Charles C. Han
The interplay between crystallization and phase separation has been intensively studied recently. In this study, we extended the research into a dynamically asymmetric blend composed of amorphous poly(methyl methacrylate) (PMMA) and crystalline poly(ethylene oxide) (PEO). The large dynamic asymmetry induces network stress in concentration growth. We find that crystallization is seriously frustrated when it couples with a simultaneous viscoelastic phase separation. In a single quench experiment, normal spherulites grew in a limited temperature range when crystallization was faster, while crystallization was frustrated at deep quenches when phase separation was faster. In a double quench experiment, crystallization was more difficult to occur after the prior phase separation at a higher temperature. The calorimetric results indicated that both melting temperatures and enthalpies of crystallization decreased in the coupled viscoelastic phase separation. We propose that it is the network stress in the concentration growth that leads to the frustration of crystallization.
研究领域:
材料科学
·
高分子物理
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2015
·
IF 2.752
Tingting Li,Zhiming Zhang,Wei Li,Ce Liu,Jianfei Wang,Libao An
Nanofibrous membranes of H 4 SiW 12 O 40 /polymethylmethacrylate (PMMA)/polyvinyl alcohol (PVA) were prepared by electrospinning technique. The sandwich structure and element composition of the membranes were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), Fourier transformation infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS). The characterization indicated that H 4 SiW 12 O 40 has been successfully loaded into the upper and bottom layers of the sandwich nanofibrous membrane, while the Keggin structure of H 4 SiW 12 O 40 was preserved. The as-prepared H 4 SiW 12 O 40 /PMMA/PVA sandwich nanofibrous membranes exhibited greatly enhanced photocatalytic efficiency (≥94.0%) in the degradation of methyl orange (MO) under ultraviolet irradiation, outperforming H 4 SiW 12 O 40 powder (4.6%) and H 4 SiW 12 O 40 /PMMA composite nanofibrous membrane (13.8%). Notably, the sandwich nanofibrous membrane could be easily separated from aqueous MO solution and the photocatalytic efficiency of the membrane had little change after three photocatalytic cycles. The great performance of the as-prepared membrane may be attributed to the water tolerance of the sandwich nanofibrous membrane and the stability of H 4 SiW 12 O 40 in the membrane. The photocatalytic mechanism of the sandwich nanofibrous membrane was also discussed.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2013
·
IF 2.206
Hong Xu,Fangfang Tong,Jian Yu,Lixiong Wen,Jun Zhang,Jiasong He
Poly(methyl methacrylate) (PMMA) and sodium montmorillonite (Na-MMT) were melt-blended with 1-dodecyl-3-methylimidazolium hexafluorophosphate (C12mimPF6) to prepare nanocomposites containing well-dispersed MMT layers in nanoscale and freely existed excess C12mimPF6. A synergistic effect of MMT and C12mimPF6 on the foaming behavior of nanocomposites was revealed in this study. At the mild conditions of 17 MPa and 35 °C, neat PMMA and PMMA/C12mimPF6 and PMMA/Na-MMT samples were not foamed, while cells were induced in nanocomposites containing a certain amount of free C12mimPF6. At 25 MPa/90 °C, foamed nanocomposites exhibited higher nucleation efficiency and cell density, and smaller cell sizes with narrower size distribution than that of neat PMMA and those binary samples. The results indicated that the MMT nanoparticles produced heterogeneous nucleation, and increased the modulus of polymer matrix to depress cell coalescence. The presence of free C12mimPF6 decreased the energy barrier for cell nucleation and facilitated the dispersion of MMT nanoparticles via in situ organic modification.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2017
·
IF 3.387
Wenzhong Ma,Yuchen Zhao,Yuxue Li,Peng Zhang,Zheng Cao,Haicun Yang,Chunlin Liu,Guoliang Tao,Fanghong Gong,Hideto Matsuyama
Surface modification of azide-decorated multiwalled carbon nanotubes (MWCNTs) with well-defined alkyne-terminated poly(methyl methacrylate) (PMMA) chains was accomplished via the combination of reversible addition fragmentation chain transfer (RAFT) and “click” chemistry. Successful attachment of PMMA onto MWCNT was confirmed by Fourier transform infrared spectroscopy, thermogravimetric analysis (TGA), gel permeation chromatography, Raman spectroscopy, and transmission electron microscopy. The highest grafting percentage ( GP ) of the PMMA chains ( GP = 23.3%) was calculated using TGA. The effect of the PMMA-grafted-MWCNTs (MWCNTs- g -PMMA) content on the performance of the poly(vinylidene fluoride) (PVDF)-MWCNTs- g -PMMA composite membrane was studied. The MWCNTs- g -PMMA was found to be well dispersed in the PVDF composite membrane matrix because of the excellent compatibility between the PMMA and PVDF chains. The composite membranes showed improved porosity, hydrophilicity, water flux, β -PVDF content, and mechanical properties at an optimal amount of 2 wt% MWCNTs- g -PMMA incorporated in the PVDF membrane matrix. In contrast, the hydroxyl functionalized MWCNTs (MWCNTs-OH) showed limited enhancement in the water flux and mechanical strength, which is mainly due to the poor dispersion of MWCNT because of the weak interaction between the MWCNT and PVDF chains. This study reveals the excellent prospect of the MWCNT-based ultrafiltration membrane with enhanced properties in water treatment applications.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Polymer Materials
·
2023
·
IF 5
Ni Sun,Chengxin Yi,Changbo Xu,Jian Xu,Meng Ma,Yanqin Shi,Huiwen He,Yulu Zhu,Si Chen,Xu Wang
The high surface resistance of polymethyl methacrylate (PMMA) causes its poor antistatic performance. Once the surface is rubbed, the electric charge will be accumulated, and the harmful static phenomena will be generated, which leads to limited application and development of PMMA. In this study, PMMA was modified by the ionic antistatic agent allyl trimethylammonium chloride (TMA), and acrylic acid was used as a compatibilizer to improve the compatibility between TMA and MMA. The surface resistance of PMMA can be reduced to 6.5 × 109 Ω by only 1.25 wt % TMA, which is 5 orders of magnitude lower than that of pure PMMA. Since the antistatic agent can be copolymerized with MMA through a double bond, the antistatic effect obtained is permanent. What is more, the core advantage of high transmittance of the composite material is maintained, and the mechanical properties and thermal stability are improved. The Vicat softening temperature of the copolymer was 96.6 °C when 1.25 wt % TMA was added, which obviously exceeds the long-term service temperature of PMMA. This research provides more possibilities for the study of high-performance PMMA.
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
JOURNAL OF SOLID STATE CHEMISTRY
·
2023
·
IF 3.3
Wanlei Geng,Yinfeng Liu,Debin Wang,Mengyu Lin,Xue Yang,Limei Zhong,Runxiong Lin,Li Ding,Lianying Wu,Dianquan Dong
Radioactive Cs + is one of the most dangerous environmental pollutants . It is necessary for radioactive Cs + management and removal. Titanium-type cesium ion sieve with a strong Ti–O bond has the advantages of structural stability, radiation resistance and no secondary contamination, which is a promising adsorbent material. In this paper, The CTO (Cs 2 Ti 6 O 13 ) is prepared for the first time by sol-gel and de-templating methods, and cesium ion sieves (HTO/PMMA) are further obtained with diluted HCl elution. Compared with the ionic sieves (HTO) prepared by direct sol-gel method, the adsorption capacity is improved from 224.32 mg/g to 299.15 mg/g. The prepared HTO/PMMA has a larger specific surface area (67.282 m 2 /g). More exchange sites are provided for the adsorption of Cs ions. Moreover, Adsorption involves the cleavage of O–H bonds and the formation of O–Cs bonds, which is a typical ion exchange reaction . A series of batch experiments are carried out. The results showed that the equilibrium adsorption capacity of HTO/PMMA is 307.69 mg/g and remained high in the interfering ion solution as well (280.38 mg/g). The pseudo second order model and Freundlich model can well describe the ion exchange process. Thermodynamic study shows that adsorption is spontaneous and exothermic, and low temperature is conducive to adsorption in H + - Cs + exchange system. Finally, the reusability of HTO/PMMA is evaluated. The adsorption capacity did not decrease significantly after 5 cycles of use. Therefore, HTO/PMMA is expected to be an excellent material for recovering radioactive Cs + .
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULES
·
2020
·
IF 5.918
Xi He,Miqiu Kong,Yanhua Niu,Guangxian Li
A series of dicationic ionic liquids (DILs) with two singly charged imidazolium rings linked by different alkyl chain lengths (C4, C6, and C8) were first synthesized. The relaxation and entanglement of poly(methyl methacrylate) (PMMA) chains in both the DILs and conventional monocationic ionic liquids (MILs) with the same anion bis[(trifluoromethyl)sulfonyl]imide ([TFSI]−) were investigated by rheological and dynamic light scattering (DLS) measurements. PMMA in DILs exhibits lower critical entanglement concentration, slower relaxation behavior, and a denser entanglement network than in their MIL counterparts, and these differences become more pronounced as the alkyl chain length decreases. The double imidazolium ring structure that provides interaction sites with PMMA chains plays a dominant role in the relaxation and entanglement of the PMMA/DIL system. As a result, the PMMA/DILs show higher modulus, greater viscosity, and better gel recovery than the PMMA/MILs at the same volume fraction. In addition, a stronger dependence on alkyl chain length is also found in PMMA/DILs. With the increase of alkyl chain length, the relaxation of PMMA becomes faster and the entanglement molecular weight increases gradually, indicating the released mobility of polymer chains. Combined with the results of DLS, it is further confirmed that the greater degree of entanglement in PMMA/DILs mainly comes from the contribution of cohesional entanglement in the system.
研究领域:
高分子科学
·
材料科学
✓ 已验证
DOI
高影响因子
OPTICAL MATERIALS
·
2020
·
IF 2.779
Yicheng Zeng,Biwei Qiu,FangFang Wang,Lei Zhou,Ying Li
Two kinds of hybrid luminescence films ([C 8 VIM][Eu (nta) 4 ]@PMMA and [C 8 VIM][Tb (acac) 4 ]@PMMA) have been synthesized by the copolymerization of MMA with lanthanide functionalized ionic liquid [C 8 VIM][Eu (nta) 4 ]. The structure and composition of the as-synthesized films have been characterized by 1 HNMR, XPS , FTIR, UV–vis, XRD , TGA and SEM. In addition, the photophysical properties of as-synthesized films have been investigated in detail by luminescence spectroscopy. It was found that the transparent and thermal stability of as-synthesized films are improved by the long chains of PMMA . More significantly, [C 8 VIM][Eu (nta) 4 ] @PMMA exhibits the improvement of photo physical properties (ƞ = 52.6%) and is selected as the representative sample to examine the potential fluorescence sensing of metal ions and anions. It has been showed highly selective and sensitive fluorescence sensing for Cu 2+ and CrO 4 2− . Meanwhile, [C 8 VIM][Eu (nta) 4 ]@PMMA exhibits a good stability in the aqueous solution, which is further used as fluorescence probe for detecting CO 3 2− . The good stability, sensitive fluorescence response and good mechanical processing properties of [C 8 VIM][Eu (nta) 4 ]@PMMA show a great potential to establish a fast response anion and cationic of aqueous solution fluorescence colorimetric sensor devices.
研究领域:
材料科学
·
光学
·
分析化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）