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Preparation and Alkylation of Carbon Nanofibers from Polymethyl Methacrylate
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作者 Stephen Mukhebi Situma Geoffrey Otieno +2 位作者 Austin O. Aluoch Dickson M. Andala James Owour 《Journal of Materials Science and Chemical Engineering》 2024年第9期55-68,共14页
Carbon nanofibers have revolutionized nanotechnology due to their potential applications in emerging frontiers of research and industrial sectors. This can be attributed to their superior properties such as higher mec... Carbon nanofibers have revolutionized nanotechnology due to their potential applications in emerging frontiers of research and industrial sectors. This can be attributed to their superior properties such as higher mechanical strength, unique surface characteristics, and improved adherence that is transmitted into the polymer matrix to form a nanocomposite with improved properties. Polymethyl methacrylate is a common carbon source for the synthesis of carbon nanofibres of its high mechanical strength, thermal stability, and low moisture and water absorbing capacity that allows its products to have several applications. In this work, we report the successful electrospinning of carbon nanofibres from Poly methyl methacrylate and functionalizing the resulting carbon nanofibres. The functionalized carbon nanofibres were analyzed to determine their solubility/dispersion in selected organic solvents, then characterized using Fourier transform infra-red spectroscopy, Raman spectroscopy, scanning electron microscopy combined with Energy dispersive spectroscopy and Thermalgravimetric analysis. 展开更多
关键词 polymethyl methacrylate Electrospinning Carbon Nanofibres ALKYLATION
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A Novel Polymethyl Methacrylate (PMMA)-TiO_2 Nanocomposite and Its Thermal and Photic Stability
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作者 ZAN Ling LIU Zhongshi FA Wenjun PENG TianYou 《Wuhan University Journal of Natural Sciences》 CAS 2006年第2期415-418,共4页
A new kind of polymethyl methacrylate (PMMA)-TiO2 nanocomposite was synthesized through polymerization. The thermal and photic stability of this PMMA TiO2 nanocomposites were investigated. The as prepared samples we... A new kind of polymethyl methacrylate (PMMA)-TiO2 nanocomposite was synthesized through polymerization. The thermal and photic stability of this PMMA TiO2 nanocomposites were investigated. The as prepared samples were characterized by scanning electron microscopy (SEM), UV-Vis spectroscopy, differential thermal analysis (DTA) and the photo-induced weight loss, The results show that the photostability of the PMMA-TiO2 nanocomposite is higher than that of the pure PMMA under UV-light irradiation, The weight loss of the pure PMMA reaches 30 % after 300 h UVirradiation, while the composite only 0.3% under the identical experimental condition. The glass transition temperature (TR) of pure PMMA is only 80℃, while the Tg of the composite reaches 258℃. Compared with pure PMMA, the thermal stability of the composite is greatly enhanced. 展开更多
关键词 polymethyl methacrylate pmma )-TiO2 nanoeomposite POLYMERIZATION thermal and photic stability
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含聚醚基团阴离子表面活性剂对PMMA表面润湿性的影响
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作者 赵濉 陈兴锋 +2 位作者 张磊 严峰 张路 《天津工业大学学报》 CAS 北大核心 2024年第3期32-39,49,共9页
为了探索同时具有聚氧异丙烯基团(PO)和聚氧乙烯基团(EO)的延展型表面活性剂分子在聚甲基丙烯酸甲酯(PMMA)表面的润湿性调控机制,对5种具有PO基团和EO基团的阴离子延展型表面活性剂十八烷基-(聚氧异丙烯)_(m)-(聚氧乙烯)_(n)-羧酸钠(C_(... 为了探索同时具有聚氧异丙烯基团(PO)和聚氧乙烯基团(EO)的延展型表面活性剂分子在聚甲基丙烯酸甲酯(PMMA)表面的润湿性调控机制,对5种具有PO基团和EO基团的阴离子延展型表面活性剂十八烷基-(聚氧异丙烯)_(m)-(聚氧乙烯)_(n)-羧酸钠(C_(18)PO_(m)EO_(n)COONa,m=5、10、15和n=5、10、15)溶液在PMMA表面的润湿性进行测试分析,考察了PO基团、EO基团和表面活性剂浓度对表面张力(γ_(LV))和接触角(θ)的影响,并计算黏附张力(γ_(LV)cosθ)、黏附功(W_(A))和固液界面张力(γ_(SL))等吸附参数。结果表明:表面活性剂浓度小于临界胶束浓度(CMC)时,C_(18)PO_(m)EO_(n)COONa分子在溶液-空气界面和PMMA-溶液界面吸附,导致γLV降低,疏水烷基链朝向水相,导致γSL升高,两者共同作用导致θ不发生变化,维持在约75°;浓度大于CMC时,C_(18)PO_(m)EO_(n)COONa分子在溶液-空气和PMMA-溶液界面同时达到饱和吸附,吸附参数趋于稳定;进一步增大浓度,C_(18)PO_(m)EO_(n)COONa分子通过疏水相互作用在PMMA-溶液界面形成聚集体,亲水基团朝向水相,导致γSL迅速减小,θ急剧降低,C_(18)PO_(5)EO_(15)C的θ可降低至约43°。随着PO基团数量的增加,C_(18)PO_(m)EO_(n)COONa在CMC时的γLV和高浓度时的θ逐渐升高;而随着EO基团数量的增加,γLV和θ几乎不发生变化。 展开更多
关键词 延展型表面活性剂 润湿性 聚甲基丙烯酸甲酯(pmma) 聚氧异丙稀基团(PO) 聚氧乙烯基团(EO)
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微波辐射无皂乳液聚合法制备单分散交联PMMA微球及其性能研究
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作者 贾慧灵 郭峰 +2 位作者 吴锦绣 谭心 李森 《塑料工业》 CAS CSCD 北大核心 2024年第6期43-48,共6页
采用无皂乳液聚合法,以二乙烯苯为交联剂,氯化钾为电解质,过硫酸钾为引发剂,在微波辐射条件下制备了聚甲基丙烯酸甲酯(PMMA)微球。研究了过硫酸钾和氯化钾的物质的量浓度对PMMA微球的平均粒径和多分散性指数的影响,分析了微波功率、搅... 采用无皂乳液聚合法,以二乙烯苯为交联剂,氯化钾为电解质,过硫酸钾为引发剂,在微波辐射条件下制备了聚甲基丙烯酸甲酯(PMMA)微球。研究了过硫酸钾和氯化钾的物质的量浓度对PMMA微球的平均粒径和多分散性指数的影响,分析了微波功率、搅拌速度与PMMA微球形貌和粒径的关系。检测了不同pH值时PMMA乳液的电动(Zeta)电位,表明PMMA表面产生负电荷,使PMMA微球呈现稳定的分散状态。制备的PMMA呈现类球形,粒径为100~400 nm,在过硫酸钾物质的量浓度为5.69×10^(-3)mol/L及氯化钾物质的量浓度为1.03×10^(-2)mol/L时,微球的多分散性指数<0.1。原子力显微镜检测了最优工艺条件下,PMMA微球的力—位移曲线并分析了其弹性力学性能。 展开更多
关键词 聚甲基丙烯酸甲酯 微波辐射 无皂乳液聚合 单分散 粒径 多分散性指数
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改性PMMA树脂本体聚合反应及拉挤工艺应用 被引量:1
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作者 曾鑫志 师俊峰 +3 位作者 关静 刘佩佩 杨威 张彦飞 《工程塑料应用》 CAS CSCD 北大核心 2024年第6期142-148,169,共8页
为了实现拉挤工艺成型纤维增强聚甲基丙烯酸甲酯(PMMA)复合材料的生产,采用了不同的助剂来调控PMMA聚合反应过程,改善甲基丙烯酸甲酯(MMA)单体的本体聚合。其中邻苯二甲酸二丁酯(DBP)作为增塑剂,N,N-二甲基苯胺(DMA)和乙酸丁酯(BAC)作... 为了实现拉挤工艺成型纤维增强聚甲基丙烯酸甲酯(PMMA)复合材料的生产,采用了不同的助剂来调控PMMA聚合反应过程,改善甲基丙烯酸甲酯(MMA)单体的本体聚合。其中邻苯二甲酸二丁酯(DBP)作为增塑剂,N,N-二甲基苯胺(DMA)和乙酸丁酯(BAC)作为反应调整助剂,将各种助剂以一定比例混入树脂体系中进行聚合。首先将各树脂体系在60℃进行20 min预聚合得到预聚体,再对不同体系的预聚体进行差示扫描量热(DSC)测试和反应动力学分析。结果表明,在不同升温速率(β)下,加入DMA体系的反应起始温度都有所降低,DMA能够加快聚合初期的反应进程,而加入BAC则使得β为25℃/min时的反应温度区间从36.1℃提高到41.3℃。使用Kissinger法和Ozawa法进行拟合分析,得到各体系反应的平均活化能(Ea),其中加入DMA使得体系Ea降低至40.71 kJ/mol,比未添加反应调整助剂的体系下降了16.9%。最终用各体系树脂进行拉挤实验,发现仅有添加了BAC的体系能够生产质量合格的产品。在拉挤工艺生产纤维增强PMMA复合材料过程中,加入一定量BAC助剂能够减缓树脂聚合集中放热,提高产品质量。 展开更多
关键词 聚甲基丙烯酸甲酯 反应动力学 自由基聚合 本体聚合 拉挤工艺
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Injectable bioactive polymethyl methacrylate-hydrogel hybrid bone cement loaded with BMP-2 to improve osteogenesis for percutaneous vertebroplasty and kyphoplasty 被引量:4
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作者 Xin Sun Xin Zhang +8 位作者 Xin Jiao Jie Ma Xingzhen Liu Han Yang Kangping Shen Yaokai Gan Jinwu Wang Haiyan Li Wenjie Jin 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2022年第2期318-332,共15页
Poly methyl methacrylate(PMMA)bone cement is used in augmenting and stabilizing fractured vertebral bodies through percutaneous vertebroplasty(PVP)and percutaneous kyphoplasty(PKP).However,applications of PMMA bone ce... Poly methyl methacrylate(PMMA)bone cement is used in augmenting and stabilizing fractured vertebral bodies through percutaneous vertebroplasty(PVP)and percutaneous kyphoplasty(PKP).However,applications of PMMA bone cement are limited by the high elasticity modulus of PMMA,its low biodegradability,and its limited ability to regenerate bone.To improve PMMA bio activity and biodegradability and to modify its elasticity modulus,we mixed PMMA bone cement with oxidized hyaluronic acid and carboxymethyl chitosan in situ cross-linking hydrogel loaded with bone morphogenetic protein-2(BMP-2)to achieve novel hybrid cement.These fabric ated PMMA-hydrogel hybrid cements exhibited lower setting temperatures,a lower elasticity modulus,and better biodegradability and biocompatibility than that of pure PMMA cement,while retaining acceptable setting times,mechanical strength,and inj ectability.In addition,we detected release of BMP-2 from the PMMA-hydrogel hybrid cements,significantly enhancing in vitro osteogenesis of bone marrow mesenchymal stem cells by up-regulating the gene expression of Runx2,Coll,and OPN.Use of PMMA-hydrogel hybrid cements loaded with BMP-2 on rabbit femoral condyle bone-defect models revealed their biodegradability and enhanced bone formation.Our study demonstrated the favorable mechanical properties,biocompatibility,and biodegradability of fabricated PMMA-hydrogel hybrid cements loaded with BMP-2,as well as their ability to improve osteogenesis,making them a promising material for use in PKP and PVP. 展开更多
关键词 polymethyl methacrylate bone cement HYDROGEL Bone morphogenetic protein-2 OSTEOGENESIS Percutaneous vertebroplasty
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Epiphyseal distraction and hybrid reconstruction using polymethyl methacrylate construct combined with free non-vascularized fibular graft in pediatric patients with osteosarcoma around knee: A case report 被引量:1
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作者 Yin-Hua Liang Hong-Bo He +2 位作者 Can Zhang Yu-Peng Liu Jun Wan 《World Journal of Clinical Cases》 SCIE 2019年第21期3632-3638,共7页
BACKGROUND In children with osteosarcoma around the knee joint without epiphysis involvement,joint-sparing surgery seems to be an ideal way to retain knee joint function.However,there are two points of debate with reg... BACKGROUND In children with osteosarcoma around the knee joint without epiphysis involvement,joint-sparing surgery seems to be an ideal way to retain knee joint function.However,there are two points of debate with regard to the technique:How to accurately achieve a safe surgical margin,and how to achieve intercalary reconstruction of the massive bone defect following resection of the tumor.CASE SUMMARY We present the case of an 8-year-old girl with osteosarcoma of the distal femur without involvement of the epiphysis.Epiphyseal distraction was applied to separate the epiphysis and metaphysis,and this provided a safe surgical margin.The massive bone defect was reconstructed with a custom-made antibioticloaded polymethyl methacrylate(PMMA)construct combined with a free nonvascularized fibular graft.Six months after surgery,bone union between the autograft and host bone was confirmed in both the proximal and distal femur by computer tomography(CT)examination.Moreover,considerable callus formation was found around the PMMA construct.After 28 mo of follow-up,there was no sign of recurrence or metastasis.The patient could walk without any aid and carry out her daily life activities satisfactorily.CONCLUSION In cases of osteosarcoma without epiphysis involvement,epiphyseal distraction can be easily applied to obtain a safe margin.Hybrid reconstruction with an antibiotic-loaded PMMA construct combined with a free non-vascularized fibular graft has the advantages of being easy to manufacture,less time-consuming to place,and less likely to get infected,while also ensuring bone union.Our case provides an alternative technique for biological reconstruction after joint-sparing surgery in patients with osteosarcoma around the knee without epiphyseal involvement. 展开更多
关键词 Epiphyseal DISTRACTION Custom-made polymethyl methacrylate construct NON-VASCULARIZED FIBULAR GRAFT OSTEOSARCOMA Case report
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Biodegradation behavior of polymethyl methacrylate−bioactive glass 45S5 composite coated magnesium in simulated body fluid 被引量:1
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作者 Zanko ROUEIN Hassan JAFARI +2 位作者 Fatemehsadat PISHBIN Rahim MOHAMMADI Abdolreza SIMCHI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第7期2216-2228,共13页
The biodegradation behavior of Mg,coated by polymethyl methacrylate as well as polymethyl methacrylate(PMMA)−bioactive glass(BG)composite was investigated.Electrophoretic deposition and dip coating techniques were ado... The biodegradation behavior of Mg,coated by polymethyl methacrylate as well as polymethyl methacrylate(PMMA)−bioactive glass(BG)composite was investigated.Electrophoretic deposition and dip coating techniques were adopted to prepare composite coating using a suspension of different percentages of the above two chemical materials.The deposited coatings were characterized using SEM,EDS,FTIR,and water contact angle measurements.Biodegradation behavior study of the coated Mg was performed using linear polarization,impedance spectroscopy,and immersion tests in simulated body fluid.The compact and homogeneous composite coating was developed as evidenced by electron microscopy results.The water contact angle measurement showed a 44°increase in the contact angle of the composite coated Mg compared to the uncoated one.The composite coating was covered by a bone-like hydroxyapatite layer after 336 h,indicating that the coating has an excellent in vitro bioactivity.The electrochemical testing results confirmed a significant reduction,96.9%,in the biodegradation rate of Mg coated with the composite prepared from 45 g/L PMMA+3.5 g/L 45S5 GB suspension compared to that of the uncoated one.Therefore,the composite coated Mg can be proposed as a promising material for biodegradable implant application. 展开更多
关键词 magnesium alloy polymethyl methacrylate bioactive glass composite coating electrophoretic deposition BIODEGRADATION
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EVA/PMMA杂化改性降凝剂对长庆含蜡原油流变性的影响机理
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作者 刘峻峰 石磊 +3 位作者 杨飞 闫锋 李其抚 聂超飞 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2024年第6期1720-1725,共6页
基于聚甲基丙烯酸甲酯(PMMA)微球良好的有机相容性,通过熔融共混法将PMMA微球与乙烯-醋酸乙烯酯共聚物(EVA28)降凝剂复合制备了EVA/PMMA杂化改性降凝剂;以长庆含蜡原油为研究对象,通过流变实验评价了EVA/PMMA杂化改性降凝剂对原油流变... 基于聚甲基丙烯酸甲酯(PMMA)微球良好的有机相容性,通过熔融共混法将PMMA微球与乙烯-醋酸乙烯酯共聚物(EVA28)降凝剂复合制备了EVA/PMMA杂化改性降凝剂;以长庆含蜡原油为研究对象,通过流变实验评价了EVA/PMMA杂化改性降凝剂对原油流变性的改善效果,利用差示扫描量热法和偏光显微镜法考察了添加降凝剂前后原油的结晶特性和蜡晶形貌变化。结果表明:与纯EVA28降凝剂相比,加入质量分数20 mg/kg EVA/PMMA杂化改性降凝剂使长庆含蜡原油的凝点从8℃降低到5℃,5℃时的黏度从40.96 mPa·s减小到35.56 mPa·s,屈服值从0.527 Pa减小到0.224 Pa。EVA/PMMA杂化改性降凝剂可以进一步降低长庆含蜡原油的析蜡点,增溶石蜡的正向作用更加显著,利于改善原油的流变性。 展开更多
关键词 含蜡原油 降凝剂 聚甲基丙烯酸甲酯 乙烯-醋酸乙烯酯共聚物 流变性 黏度 蜡晶
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Effect of Methyl Methacrylate– Acrylonitrile -Butadiene–Styrene (MABS) on the Mechanical and Thermal Properties of Poly (Methyl Methacrylate) (PMMA)-Fly Ash Cenospheres (FAC) Filled Composites 被引量:1
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作者 M. B. Kulkarni P. A. Mahanwar 《Journal of Minerals and Materials Characterization and Engineering》 2012年第4期365-383,共19页
With the advent of plastics and the wide range of fillers that are available have made modifications as precise as the tailored resins themselves. To modify the properties of polymer either by using fillers or by prep... With the advent of plastics and the wide range of fillers that are available have made modifications as precise as the tailored resins themselves. To modify the properties of polymer either by using fillers or by preparation of polymer blends gives rise to new materials with tailored properties. More complex, three-component systems, obtained by the addition of polymeric modifier to polymer filled composites may be of interest. Use of Fly ash cenospheres is very attractive because it is inexpensive and its use can reduce the environmental pollution to a significant extent. In the present study, Poly (Methyl Methacrylate) (PMMA)-Fly ash cenospheres composites were prepared using extrusion followed by Injection molding. The effect of matrix modification with Methyl methacrylate– acrylonitrile -butadiene–styrene (MABS) on the performance of PMMA- Fly ash cenospheres compositions was also, studied. It was found that with the addition of Fly ash cenospheres particulate as filler in PMMA showed marginal reduction in Tensile Strength, % Elongation and Impact strength and improvement in Flexural Strength, Heat Deflection Temperature and Vicat Softening Point. Compared with PMMA-cenospheres composites, the notched Impact Strength of the PMMA/MABS/cenospheres composites showed marginal enhancement in values at higher loading of cenospheres. The optimum performances in mechanical and thermal properties were obtained when the ratio of MABS to cenospheres was 1:2. 展开更多
关键词 Poly (Methyl methacrylate) (pmma) Fly ash cenospheres (FAC) Methyl methacrylate ACRYLONITRILE -butadiene–styrene (MABS) Mechanical and Thermal Properties.
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Measurement of Secondary Electron Energy Spectra of Polymethyl Methacrylate 被引量:1
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作者 Ming Weng Wan Liu +2 位作者 Ming Yin Fang Wang Meng Cao 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第4期108-112,共5页
We report on a novel and convenient method of measuring secondary electron spectra for insulators in a secondary electron yield measurement system with a planar grid analyzer configuration and a metal mesh probe. In t... We report on a novel and convenient method of measuring secondary electron spectra for insulators in a secondary electron yield measurement system with a planar grid analyzer configuration and a metal mesh probe. In this measurement, the planar grid is negatively biased to force some emitted secondary electrons to return to the sample surface and to neutralize charges accumulated on the sample during the previous beam irradiation. The surface potential of the sample is then measured by use of a metal mesh probe. The grid bias for neutralization corresponding to the zero surface potential is determined based on the linear relationship between the surface potential and the grid bias. Once the surface potential equals zero, the secondary electron spectra of polymethyl methacrylate(PMMA) are studied experimentally by measuring the -curve and then fitting it to Everhart's formula. The measurement results show that the peak energy and the full width at half maximum of the spectra are 4.26 eV and 14.06 eV, respectively. 展开更多
关键词 SE In Measurement of Secondary Electron Energy Spectra of polymethyl methacrylate
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A Novel Method for Preparing Approximately Micron-sized Polymethyl Methacrylate Microspheres with Clear Surface
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作者 DiQiangWANG BaiLingLIU +2 位作者 JieHU XiaoQinLIN MinZHANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第3期371-374,共4页
Polymethyl methacrylate (PMMA) microspheres with clear surface and diameter close to 1 祄 were synthesized by newly soap-free emulsion polymerization. The results showed that the presence of ethanol and NaCl made the... Polymethyl methacrylate (PMMA) microspheres with clear surface and diameter close to 1 祄 were synthesized by newly soap-free emulsion polymerization. The results showed that the presence of ethanol and NaCl made the increase of diameter and distribution, while the presence of toluene could avoid the problem of the increase of distribution, resulting a harvest of PMMA microspheres with a diameter close to 1 祄. 展开更多
关键词 Soap-free emulsion polymerization polymethyl methacrylate microspheres competi- tion solvent COSOLVENT ELECTROLYTE diameter and distribution.
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Preparation and Fluorescence Properties of Polymethyl Methacrylate Resin Incorporated with Sodium Tris (Pyridine Dicarboxylato) Europate
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作者 罗一帆 安保礼 +3 位作者 叶剑清 龚孟濂 石建新 麦堪成 《Journal of Rare Earths》 SCIE EI CAS CSCD 2002年第4期318-321,共4页
Based on the strong fluorescence and the highly thermal stability of sodium tris (pyridine dicarboxylato) europate (Na 3Eu(DPA) 3), polymethyl methacrylate (PMMA) composite material incorporated with the complex, P... Based on the strong fluorescence and the highly thermal stability of sodium tris (pyridine dicarboxylato) europate (Na 3Eu(DPA) 3), polymethyl methacrylate (PMMA) composite material incorporated with the complex, PMMA: Na 3Eu(DPA) 3, was prepared at 250 ℃. The fluorescence behavior of PMMA: Na 3Eu(DPA) 3 material was examined. The results show that the composite material keeps the luminescent characteristics of the Eu 3+ chelate after PMMA is incorporated with Na 3Eu(DPA) 3, and strong orange-red emission of the composite was observed. The fluorescence intensity of the composite material increases with the increase of the weight ratio of Na 3Eu(DPA) 3 to PMMA, but the relationship is not linear. 展开更多
关键词 rare earths rare earth organic complex Na 3Eu(DPA) 3 polymethyl methacrylate resin composite material FLUORESCENCE
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本体聚合PMMA基复合介质膜的储能特性研究
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作者 蔡博 赵月涛 +5 位作者 孟祥硕 周榆久 王礼坤 叶虎 潘齐凤 徐建华 《绝缘材料》 CAS 北大核心 2024年第4期22-27,共6页
目前有机薄膜电容器中的介质材料多为线性电介质,这类聚合物的介电常数通常较低,造成电容器储能密度普遍偏低,而新型高储能聚合物介质材料一般又存在介质损耗高的问题。聚甲基丙烯酸甲酯(PMMA)与高储能含氟聚合物的相容性较好,常被用来... 目前有机薄膜电容器中的介质材料多为线性电介质,这类聚合物的介电常数通常较低,造成电容器储能密度普遍偏低,而新型高储能聚合物介质材料一般又存在介质损耗高的问题。聚甲基丙烯酸甲酯(PMMA)与高储能含氟聚合物的相容性较好,常被用来改善后者的力学和击穿性能,但市售的PMMA存在本征介质损耗过高的问题。为了降低PMMA的介质损耗,本文用甲基丙烯酸甲酯(MMA)与苯乙烯(St)合成MMA-St共聚物(MS),将不同比例的MS掺入本体聚合的PMMA中形成复合体系,并研究复合体系的介电特性、储能特性及绝缘特性。结果表明:该复合体系可以显著降低PMMA的介质损耗,相较于PMMA更适合作为高储能聚合物的改性材料。其中复合10%MS的介质膜在5 500 kV/cm电场下获得了5 J/cm^(3)的放电能量密度,充放电效率达到83%。 展开更多
关键词 聚甲基丙烯酸甲酯 介质损耗 储能 全有机复合介质膜
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SMA含量对PMMA/ASA/SMA三元合金材料性能的影响
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作者 林明华 郑斌 +1 位作者 郭建兵 王华 《工程塑料应用》 CAS CSCD 北大核心 2024年第9期149-153,共5页
为了提升聚甲基丙烯酸甲酯(PMMA)的综合性能并拓宽其在抗冲击和高温环境下的应用范围,采用苯乙烯-马来酸酐共聚物(SMA)和丙烯腈-苯乙烯-丙烯酸酯三元共聚物(ASA)作为改性剂,通过熔融共混技术,制备了PMMA/ASA/SMA三元合金材料。在SMA和AS... 为了提升聚甲基丙烯酸甲酯(PMMA)的综合性能并拓宽其在抗冲击和高温环境下的应用范围,采用苯乙烯-马来酸酐共聚物(SMA)和丙烯腈-苯乙烯-丙烯酸酯三元共聚物(ASA)作为改性剂,通过熔融共混技术,制备了PMMA/ASA/SMA三元合金材料。在SMA和ASA总质量分数固定为30%的情况下,研究了SMA含量变化对合金材料力学性能、耐热性能以及组分相容性的影响。结果表明,添加SMA和ASA可显著提升PMMA的断裂伸长率和缺口冲击强度,随着SMA含量的增加,合金材料的拉伸强度和弯曲强度逐渐提升,断裂伸长率先升高后降低,当SMA质量分数为5%时达到最高,较未添加SMA的材料提高32.1%,缺口冲击强度下降,但仍远高于纯PMMA。此外,合金材料的热变形温度与SMA含量成正相关关系,每增加质量分数1%的SMA,热变形温度约提高0.36℃,在SMA质量分数为20%时,热变形温度可提升至103.9℃。SMA的加入有效提高了合金材料的玻璃化转变温度(Tg),与未添加SMA的材料相比,添加质量分数20%SMA的合金材料的Tg从122.50℃提升至133.01℃,增幅达10.51℃。此外,合金材料的损耗因子呈现出单一峰值,表明PMMA/ASA/SMA体系具有良好的相容性。 展开更多
关键词 苯乙烯-马来酸酐共聚物 聚甲基丙烯酸甲酯 丙烯腈-苯乙烯-丙烯酸酯三元共聚物 合金材料 耐热性能 力学性能
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PMMA对聚碳酸酯建筑装饰材料耐刮擦性能的影响
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作者 李鹏飞 沈寒峰 《山西化工》 CAS 2024年第7期37-38,52,共3页
为了提高建筑装饰用聚碳酸酯(PC)的耐刮擦性能,通过在聚碳酸酯(PC)中添加聚甲基丙烯酸甲酯(PMMA)的方法来提高材料性能,通过实验测试的手段研究PMMA对聚碳酸酯材料耐刮擦性能和光泽度的影响。研究结果表明:当PMMA加入量上升后,材料硬度... 为了提高建筑装饰用聚碳酸酯(PC)的耐刮擦性能,通过在聚碳酸酯(PC)中添加聚甲基丙烯酸甲酯(PMMA)的方法来提高材料性能,通过实验测试的手段研究PMMA对聚碳酸酯材料耐刮擦性能和光泽度的影响。研究结果表明:当PMMA加入量上升后,材料硬度随之提高,通过十字刮擦方法得到的色差值变化发生了先升高后降低的情况,材料色牢度降低。当摩擦次数上升后,所有材料的光泽度先迅速下降之后到达一个稳定的状态。PC/PMMA高分子材料的耐刮擦性能得到了改善。该研究有助于提高建筑装饰材料的高分子特性,为后续的化工精炼奠定一定的理论基础。 展开更多
关键词 聚甲基丙烯酸甲酯 聚碳酸酯 耐刮擦性能 建筑装饰材料
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Effect of local massage on prevention and treatment of intra-arterial polymethyl methacrylate embolism complications:An experimental animal study
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作者 Fangfei Nie Hongbin Xie 《Chinese Journal of Plastic and Reconstructive Surgery》 2022年第1期6-12,共7页
Background:Massage is generally believed to be a simple and effective method for preventing necrosis when intravascular injection emboli are suspected.Due to its good dispersive properties,polymethyl methacrylate(PMMA... Background:Massage is generally believed to be a simple and effective method for preventing necrosis when intravascular injection emboli are suspected.Due to its good dispersive properties,polymethyl methacrylate(PMMA)was used as the test filler.The main purpose of this study was to observe whether local massage as a simple remedial measure can promote the diffusion of filler and reduce the necrosis rate for intra-arterial embolism.Methods:Rabbit ears with the central ear artery(CEA)main trunk totally or segmentally obstructed 5 min after PMMA injection were studied.In order to simulate the massage effect of the fingers,the massage group was treated with a small beauty massage bar with a fixed vibration frequency along the direction of the blood flow.CEA blood flow and skin lesions were also analyzed.Results:The baseline data were similar between the control and massage groups.Compared to the control group,the recanalization rate of the CEA trunk in the treatment group increased significantly after massage.However,there was no significant difference in the visible rate of transparent embolus on the 1st day after treatment,nor in the necrosis degree or area of soft tissue damage on the 7th day after treatment.Further analysis showed that massage tended to have a positive effect on segmentally obstructed cases at 5 min after injection but a negative effect on totally obstructed ears at 5 min.Conclusion:Local massage cannot reduce the complications of tissue necrosis after intra-arterial PMMA injection.Prevention is key to reducing complications. 展开更多
关键词 Cosmetic filler polymethyl methacrylate Local massage Intra-arterial injection EMBOLISM NECROSIS
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GTO/PMMA复合材料的制备及其透明隔热性能的研究
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作者 王勇 赵娣芳 +2 位作者 吴少杰 郝思宇 张义宇 《巢湖学院学报》 2023年第6期86-92,共7页
为了减少太阳热辐射对人体的损害已经消耗了地球的大量资源,目前研究更加新型的环保热屏蔽材料势在必行。采用正交试验法研究了溶剂载体种类、分散剂类型、改性时间及球磨时间对铯钨青铜(GTO)在甲基丙烯酸甲酯(MMA)中分散稳定性的影响... 为了减少太阳热辐射对人体的损害已经消耗了地球的大量资源,目前研究更加新型的环保热屏蔽材料势在必行。采用正交试验法研究了溶剂载体种类、分散剂类型、改性时间及球磨时间对铯钨青铜(GTO)在甲基丙烯酸甲酯(MMA)中分散稳定性的影响。进一步研究了不同比例GTO/PMMA复合材料对隔热效果的影响并分析了其隔热机理。采用扫描电镜(SEM)、紫外-可见-近红外分光光度计对样品的微观形貌及近红外吸收性能进行了表征,通过自制隔热装置对其隔热性能进行了评价。实验结果表明:溶剂载体选用对苯二甲酸二辛酯(DOTP)为最优,在分散剂KENT-1103作用下,球磨时间24 h、振荡分散时间为24 h的稳定性最好;结合SEM和透射光谱分析,PMMA-GTO复合材料的相容性好,PMMA-0.4 wt%GTO的样品可见光透过率为39.96%,近红外光阻隔率96.91%,雾度为8.92%,隔热温度10.1℃,综合性能最好。 展开更多
关键词 聚甲基丙烯酸甲酯复合材料 分散稳定性 近红外吸收性能 隔热性能
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AN EPOXY/(METHYL METHACRYLATE)INTERPENETRATING POLYMER NETWORK FOR NONLINEAR OPTICS
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作者 张灵志 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1999年第5期435-440,共6页
An interpenetrating polymer networks (IPN) consisting of an epoxy-based polymer network and a polymethyl methacrylate network were synthesized and characterized. The IPN showed only one T-g, and hence a homogeneous-ph... An interpenetrating polymer networks (IPN) consisting of an epoxy-based polymer network and a polymethyl methacrylate network were synthesized and characterized. The IPN showed only one T-g, and hence a homogeneous-phase morphology was suggested. The second-order nonlinear optical coefficient (d(33)) of the IPN was measured to be 1.72 X 10(-7) esu. The study of NLO temporal stability at room temperature and elevated temperature (100 degrees C) indicated that the IPN exhibits a high stability in the dipole orientation due to the permanent entanglements of two component networks in the IPN system. Long-term stability of second harmonic coefficients was observed at room temperature for more than 1000 h. 展开更多
关键词 interpenetrating polymer networks second-order optical nonlinearity epoxy-based polymer polymethyl methacrylate
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PC/PMMA/GE复合材料的结构与性能
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作者 彭世贵 陈蔚洁 +2 位作者 杨照 薛斌 徐国敏 《现代塑料加工应用》 CAS 2023年第2期9-11,19,共4页
以石墨烯(GE)、聚碳酸酯(PC)及聚甲基丙烯酸甲酯(PMMA)为原料,制备了一系列PC/PMMA,PC/PMMA/GE复合材料。研究了PC,PMMA,GE不同配料比以及GE对PC/PMMA复合材料相结构、流变性能、力学性能的影响。结果表明:当PMMA质量分数达到40.00%时,P... 以石墨烯(GE)、聚碳酸酯(PC)及聚甲基丙烯酸甲酯(PMMA)为原料,制备了一系列PC/PMMA,PC/PMMA/GE复合材料。研究了PC,PMMA,GE不同配料比以及GE对PC/PMMA复合材料相结构、流变性能、力学性能的影响。结果表明:当PMMA质量分数达到40.00%时,PC/PMMA复合材料相结构从海岛型转变为共连续型。加入GE有利于细化PC/PMMA复合材料分散相粒径。增加PMMA含量和加入GE均能降低复合材料复数黏度。另外,GE在明显提高PC/PMMA复合材料断裂伸长率的同时,保证其拉伸强度基本不降低,这为高性能复合材料的设计与制备提供了一种思路。 展开更多
关键词 石墨烯 聚碳酸酯 聚甲基丙烯酸甲酯 相结构 断裂伸长率
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