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聚丙烯酸酯/ TiO2-SiO2纳米杂化材料的制备与性能研究 总被引:4,自引:0,他引:4
用原位复合、溶胶-凝胶法成功制得热固性聚丙烯酸酯基纳米SiO2包覆TiO2的有机-无机纳米杂化材料,通过红外光谱(FT-IR)、透射电镜(TEM)、扫描电镜(SEM)、紫外-可见光谱(UV-Vis)及热失重和差示扫描量热法(TG-DSC)等对材料的结构和性能进行了表征.实验证明了聚丙烯酸酯/TiO2-SiO2纳米杂化材料对紫外线有很好的屏蔽效果及更好的热稳定性. 相似文献
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将纳米Al2O3-SiO2、Si3N4分别均匀分散于聚酰亚胺(PI)前驱体聚酰胺酸中,经过热亚胺化制备了PI/纳米Al2O3-SiO2和PI/纳米鼠N4杂化材料。通过傅里叶变换红外光谱仪、X射线衍射仪、高温微量热天平、静态热机械分析仪和差示热分析仪对杂化材料的微观结构及热性能进行了研究,结果表明,杂化材料中聚酰亚胺和无机纳米粒子之间存在相互作用,形成了复合相态结构;加入纳米Al2O3,SiO2、Si3N4后杂化材料的热稳定性均高于纯聚酰亚胺,但并不完全随无机纳米粒子含量的增加而提高;与纯PI相比,在90~130℃的温度范围内PI-8%Al2O3-SiO2、PI-8%鼠Si3N4热膨胀系数分别降低了约11%和47%,加入8%纳米Al2O3-SiO2、Si3N4后杂化材料的热导率分别提高了约8%和13%。PI/纳米Al2O3-SiO2、Si3N4杂化材料不仅保留了PI原有的优异性能,而且充分发挥了纳米无机粒子对PI的特殊改性性能。 相似文献
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PU/SiO2杂化材料的制备与表征 总被引:1,自引:0,他引:1
用溶胶-凝胶法制备了一系列聚氨酯(PU)/SiO2杂化材料,通过扫描电子显微镜和傅里叶变换红外光谱考察了杂化材料的相容性、微观相互作用以及介电性能。实验发现.水和催化剂的用量控制得当可得到分散均匀的杂化材料;在10μm厚的聚对苯二甲酸乙二酯(PET)薄膜上涂有2μm厚的PU/SiO2杂化材料,体系的介电常数较纯PET薄膜提高1倍多。 相似文献
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通过溶胶-凝胶法制备了TiO2溶胶,与聚甲基丙烯酸甲酯(PMMA)进行杂化处理制得了TiO2/PMMA纳米复合材料.并将不同量的溶胶与几种不同摩尔质量的PMMA进行复合,得到多种样品.通过透射电镜(TEM)、红外光谱(FTIR)、紫外-可见光谱(UV-Vis)、热失重(TGA)分析研究了TiO2/PMMA纳米复合材料的结构和性能,从而由溶胶含量、PMMA摩尔质量等不同因素对复合材料性质产生的影响作出了解释.结果表明当溶胶含量为1%、PMMA的摩尔质量较低(37.3万g/mol)时,TiO2微粒在聚合物中的分散性较好,粒径较均一,TiO2的加入使得材料的抗紫外线性和热稳定性都有所提高. 相似文献
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溶胶-凝胶法制备环氧树脂/SiO2杂化材料的研究 总被引:4,自引:0,他引:4
以环氧树脂、正硅酸乙酯(TEOS)、У-氨丙基三乙氧基硅烷(KH-550)为原料,采用溶胶-凝胶(Sol-Gel)法制备了环氧树脂/SiO2杂化材料。研究了TEOS用量、KH-550用量、温度对环氧树脂/SiO2杂化材料性能的影响。利用透射电镜(TEM)研究了SiO2在杂化材料中的分散状态,利用扫描电镜(SEM)对杂化材料的拉伸断口的微观形貌进行了研究,并用差示扫描量热(DSC)法研究了杂化材料的耐热性能。结果表明,TEOS含量在3%,KH-550含量在2%、反应温度在60℃时,杂化材料的拉伸强度、断裂伸长率、冲击强度和弯曲强度分别提高了30.1%、53.9%、34.4%、12.5%;生成的SiO2颗粒的平均尺寸为20nm左右;杂化材料玻璃化温度比纯环氧树脂提高20℃以上。 相似文献
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王国祥 《化学工业与工程技术》2008,29(6):7-10
以丙烯酰胺为有机相,通过钛酸正丁酯的水解引入二氧化钛无机相,采用溶胶-凝胶法制备了聚丙烯酰胺(PAM)/二氧化钛(TiO2)水溶性高聚物杂化材料。讨论了二氧化钛溶胶质量分数、单体质量分数对聚合反应转化率的影响;对合成的杂化材料进行了红外、热性能表征。实验结果表明,二氧化钛包裹在聚丙烯酰胺内部,同时,合成的杂化材料耐热性能有所提高。 相似文献
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《Ceramics International》2021,47(23):32963-32968
Effects of carbon source in single-source ZrC-based liquid precursors on the properties of the precursors and precursor-derived nano ZrC powders were investigated. The liquid precursors were prepared by directly blending and heating zirconium n-butoxide with either 2,4-pentanedione, benzoyl acetone or 1,3-diphenyl-1,3-propanedione additives which have the same chemical composition and structure except for the number of benzene rings (0, 1 and 2, respectively) in order to control the carbon content in the precursors. The ceramic yield of the precursor decreased as the number of benzene rings in the precursors increased. The stability of the precursors in air and the carbon content of the ceramic powder increased when using 1,3-diphenyl-1,3-propanedione additive. X-ray pure nano zirconium carbide powders with ultra-fine size (30 nm), isotropic shape and homogeneous particle size distribution were synthesized from the liquid precursors containing two benzene rings in the structure. Compared with ZrC powders derived from the precursors containing zero or one benzene ring, the powder from the precursor containing two benzene rings was finer and more homogeneous in size distribution. 相似文献
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Peng Yu Gang Liu Kaican Li An Huang Binyi Chen Haoyang Mi Shuidong Zhang Xiangfang Peng 《Polymer Composites》2016,37(6):1864-1873
The article surveyed the fabrication of polystyrene (PS)/nano‐CaCO3 foams with unimodal or bimodal cellular morphology from extrusion foaming using supercritical carbon dioxide (sc‐CO2). In order to discover the factors influenced the cell structure of PS/nano‐CaCO3 foams, the effects of die temperature, die pressure, and nano‐CaCO3 content on cell size, density, and morphology were investigated detailed. The results showed that the nano‐CaCO3 content affected the cell size and morphology of PS/nano‐CaCO3 foams significantly. When the die temperature and pressure was 150°C and 18 MPa, respectively, the foams with 5 wt% nano‐CaCO3 exhibited the unimodal cellular morphology. As the nano‐CaCO3 content increased to 20 wt%, a bimodal cell structure of the foams could be obtained. Moreover, it was found that the bimodal structure correlated more strongly with the pressure drop than the foaming temperature. The article revealed that unimodal or bimodal cellular morphology of PS/nano‐CaCO3 foams could be achieved by changing the extrusion foaming parameters and nano‐CaCO3 content. POLYM. COMPOS., 37:1864–1873, 2016. © 2015 Society of Plastics Engineers 相似文献
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借助Materials Studio软件建立了0.902nm、1.997nm、3.000nm、4.000nm孔径的活性炭狭缝孔模型,采用巨正则蒙特卡洛模拟(Grand Canonical Monte Carlo)的模拟方法计算了其对挥发性有机物(VOCs,如异己烷、苯、甲苯、丙酮和甲醇)的吸附数据,考察了活性炭孔径的变化对VOCs吸附性能的影响,并对实际应用进行指导。模拟结果显示:活性炭对VOCs的吸附受孔径和吸附能的共同影响,在293.15K、各物质饱和蒸气压p0下,随着孔径的增大,吸附质吸附剂之间的亲和力呈下降趋势。活性炭孔径由0.902nm增加到4.000nm对异己烷、苯、甲苯的饱和吸附量逐渐增大,而4.000nm孔径活性炭对丙酮饱和吸附量小于3.000nm孔径活性炭,3.000nm、4.000nm孔径活性炭对甲醇饱和吸附量小于1.997nm孔径活性炭。在工业废气VOCs吸附回收中选择0.902~1.997nm孔径活性炭能够达到最佳效果。 相似文献
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Melany Omer-Mizrahi 《Polymer》2010,51(6):1222-1230
Polystyrene template microspheres of narrow size distribution were prepared by dispersion polymerization of styrene in 2-methoxyethanol. Uniform polystyrene/poly(divinyl benzene) composite microspheres were formed by a single-step swelling process of the polystyrene template microspheres with dibutyl phthalate droplets containing divinyl benzene and benzoyl peroxide, followed by polymerization at 73 °C. Uniform poly(divinyl benzene) microspheres of higher surface area were produced by dissolution of the template polystyrene part of the former composite microspheres with methylene chloride. Hydroperoxide conjugated polystyrene and poly(divinyl benzene) microspheres were produced by controlled ozonolysis of these microspheres. Polyepoxide conjugated microspheres were then formed by redox graft polymerization of glycidyl methacylate on the hydroperoxide-conjugated microspheres. Microspheres with different properties, e.g., size, size distribution, shape, surface morphology, surface area, etc., have been prepared by changing various parameters belonging to the ozonolysis and the grafting polymerization processes, e.g., ozonolysis conditions and monomer volume. Trypsin was then covalently bound to the polyepoxide conjugated microspheres by interacting the epoxide groups of the particles with primary amino groups of the enzyme. A comparison between the enzymatic activity of the conjugated and the free trypsin was also established. 相似文献
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采用自由基原位悬浮聚合方法,由苯乙烯/纳米无机粒子(NIP)聚合制备聚苯乙烯纳米复合材料(PSNC),再以戊烷为发泡剂制备了可发性聚苯乙烯纳米复合材料(EPSNC),筛选了NIP改性剂的种类。利用凝胶渗透色谱仪和热重分析仪对EPSNC进行表征,研究了EPSNC的分子结构和热性能,采用扫描电子显微镜对EPSNC泡体内部微观形貌进行表征,研究NIP含量对其泡体微观形貌的影响规律。结果表明,以钛酸酯偶联剂改性NIP (M NIP)聚合产率最高;M NIP用量在一定范围内对EPSNC的相对分子质量影响不大,但相对分子质量分布变窄;含有M NIP的EPSNC的热稳定性明显提高;EPSNC发泡时NIP起成核作用,M NIP能够均匀地分散在EPSNC中,其泡孔堆积有序,细密一致,且多为闭孔结构。 相似文献
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Air‐stable Fe magnetic nanoparticles entrapped within carbon and porous crosslinked polystyrene microspheres of narrow size distribution were prepared by the following sequential steps: (1) Polystyrene/poly(divinyl benzene) and polystyrene/poly(styrene‐divinyl benzene) uniform micrometer‐sized composite particles were prepared by a single‐step swelling of uniform polystyrene template microspheres dispersed in an aqueous continuous phase with emulsion droplets of dibutyl phthalate containing the monomers divinyl benzene and styrene and the initiator benzoyl peroxide. The monomers within the swollen polystyrene template microspheres were then polymerized by raising the temperature to 73°C; (2) Porous poly (divinyl benzene) and poly(styrene‐divinyl benzene) uniform crosslinked microspheres were prepared by dissolution of the polystyrene template part of the former composite particles; (3) Uniform magnetic poly(divinyl benzene)/Fe and poly(styrene‐divinyl benzene)/Fe composite microspheres were prepared by entrapping Fe(CO)5 within the porous crosslinked microspheres, by suction of the Fe complex into the dried porous particles, followed by decomposition of the encapsulated Fe(CO)5 at 200°C in Ar atmosphere; (4) Uniform magnetic air‐stable C/Fe composite microspheres were prepared similarly, apart from changing the decomposition temperature from 200 to 600°C. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
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选用Pb(Ac)_2为铅源,分别以Na_2S_2O_3和硫代乙酰胺为硫源,分别以PVA、十二烷基苯磺酸钠、乙二胺为表面活性剂,在一定剂量电子束辐射下,元素Pb和S发生反应,合成均匀分散的PbS纳米晶体颗粒。用X射线粉末衍射,原子力显微镜,紫外光谱和荧光光谱对产物的组成、大小、形貌以及发光效应进行表征。结果表明,产物纳米PbS为立方晶系结构,平均粒径为30nm. 相似文献
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Results are reported on incompatibility measurements of a high molecular weight polystyrene of poly-α-methylstyrene in the isorefractive polymer solvent mixtures polybutadiene/benzene and polyisoprene/benzene respectively by means of the light scattering method. It turns out that polystyrene in cis-1,4-polybutadiene/benzene mixtures is more incompatible as in configurationally non-uniform polybutadiene/benzene mixtures. Furthermore the measurements showed that the incompatibility of polystyrene with cis-1,4-polybutadiene and with cis-1,4-polyisoprene is practically identical. Whereas the degree of incompatibility of polystyrene and poly-α-methylstyrene with polybutadienes in benzene is also nearly the same the incompatibility of polystyrene with cis-1,4-polyisoprene/benzene however is much greater than with poly-α-methylstyrene. An empirical interpretation of these and of former results on other polymer system is discussed. 相似文献
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微乳液法制备纳米TiO2/活性炭复合体的研究 总被引:1,自引:0,他引:1
纳米TiO2是一种高效的光催化剂,而光催化剂的制备和固化是光催化技术应用的关键。采用油酸/正丁醇/NaOH溶液制备了纳米TiO2/活性炭复合材料。用微乳体系制备出纳米二氧化钛前驱体,然后由表面活性剂稳定和保护的纳米粒子在氢键吸附等作用力下包覆于活性炭载体的表面。用热重-差热分析、扫描电镜、红外光谱法对其结构进行分析。结果表明:所制得TiO2粒径为20 nm左右,呈球形分布于活性炭表面。用分光光度法测得TiO2的包覆率为28.2%。 相似文献