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为使纳米白炭黑具有强疏水性,在传统硅烷偶联剂改性工艺基础上,引入了硬脂酸进行复合改性,制备出了具有高疏水性能的纳米白炭黑。采用红外光谱(FTIR)、X射线光电子能谱(XPS)、接触角测试和沉降实验等研究了改性后试样的结构和性能,并讨论分析了复合改性的机理。结果表明:通过硅烷偶联剂改性,白炭黑表面接枝了氨基(—NH2)基团;硬脂酸改性后,—NH2基团与硬脂酸的羧基基团(—COOH)形成酰胺键(—CONH—),白炭黑最终表面形成了疏水性能优异的—(CH2)3COHN—(CH2)16CH3基团。复合改性后的纳米白炭黑表面通过化学键接枝了硬脂酸分子,与水的接触角达到了140°,具有优异的疏水性能。 相似文献
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白炭黑(SiO_2·n H_2O)作为橡胶补强剂广泛应用于汽车轮胎工业。以硅烷偶联剂A171为改性剂对白炭黑进行表面改性,考察了改性温度、时间、pH和改性剂质量分数对白炭黑性能的影响,采用X射线衍射(XRD)、热重(TG)、红外光谱(FTIR)、透射电镜(TEM)等对白炭黑进行表征。适宜的改性条件为:改性温度为90℃,改性时间为120 min,pH为2.5,A171质量为白炭黑湿凝胶质量的3.0%时,改性后白炭黑的活化度达100%,表面硅羟基下降,提高了传统白炭黑的疏水性。将白炭黑应用于丁苯橡胶时,300%、500%定伸应力较未改性提高了88.5%、86.3%,拉伸强度提高16.2%,体积磨耗下降12.6%,提高了硫化胶的力学性能和补强性能。 相似文献
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以正辛基三乙氧基硅烷(LM-N308)为有机表面改性剂,用相转移法对金红石相纳米TiO2进行有机表面改性。采用了傅里叶变换红外光谱(FTIR)、热分析(TG-DTA)、X 射线光电子能谱(XPS)、高分辨透射电镜(HRTEM)、亲油化度实验等对所得的纳米TiO2进行了表征。红外光谱和X射线光电子能谱表明LM-N308以化学键合的方式结合在纳米TiO2表面。HRTEM结果显示,在纳米TiO2的表面存在厚度均匀约2 nm的有机包覆层。TG和亲油化度实验数据表明,纳米TiO2表面化学吸附的LM-N308的饱和质量分数为7.0%~9.7%。分散性实验表明,经LM-N308表面改性的纳米TiO2由亲水性变成了疏水性。 相似文献
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硅烷偶联剂对纳米氧化锌的表面改性研究 总被引:3,自引:0,他引:3
采用硅烷偶联剂KH-570对纳米ZnO进行表面改性,研究了硅烷偶联剂用量、pH值、时间及反应温度等因素对纳米ZnO表面改性的影响,利用亲油化度实验、红外光谱(IR)、热重(TG)、透射电镜(TEM)等手段表征了纳米ZnO的改性效果和结构。红外光谱和热重研究表明,KH-570以化学键合的方式结合在纳米ZnO的表面,并形成了有机包覆层。经测量,纳米ZnO表面的KH-570的质量分数为4.6%;讨论了产生KH-570理论包覆量与实际包覆量差异的原因。TEM图表明经KH-570改性过的纳米ZnO的分散性大大提高;亲油化度实验表明,当硅烷偶联剂用量为6%,pH值为6.5,反应温度为85℃,反应2 h时,纳米ZnO改性效果最好。 相似文献
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以煤矸石为原料,气相-液相法直接制成纳米白炭黑(SiO2·xH2O)。通过控制氟化氢通入速度和四氟化硅水解速度,并加入乙醇为分散剂,利用X射线粉末衍射(XRD)、红外光谱分析(IR)和透射电镜(TEM)等方法对制成的白炭黑粉体样品进行表征。结果表明,制备的纳米白炭黑粉体呈球形、粒径分布范围为15~20nm,纯度99.95%。并对制作白炭黑过程产生的废滤液可以综合利用,在滤液中加入一定量的碱化剂后,调节pH至3.0左右,使AlC13和FeCl3发生聚合反应,制备出聚合氯化铝铁,试验表明,其絮凝效果良好。 相似文献
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采用自制的大分子表面改性剂对纳米TiN进行表面改性,对改性前后的纳米TiN进行红外光谱分析(FTIR)、热重分析(TGA)、粒径分析、接触角等表征。结果表明,大分子改性剂和纳米TiN的表面发生化学键合,有效地阻止了纳米TIN的团聚,使得纳米T.N疏水性提高。用改性后的纳米TiN填充丙烯酸酯橡胶(ACM),制备纳米TiN/ACM复合材料,透射电镜(TEM)观察到纳米TiN颗粒在ACM基体中分散良好;复合材料性能检测结果显示:材料的常规力学性能、耐油、耐热空气老化和耐磨性能均有明显提高。 相似文献
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为使纳米氢氧化镁的表面性质由亲水性变为亲油性,以使其在高聚材料中能够更好地分散填充并减少团聚,采用新型纳米聚丙烯酸酯乳液作为改性剂,对纳米氢氧化镁进行了表面改性研究。采用活化指数测试、接触角测试、红外光谱分析及热重分析等手段研究了改性纳米氢氧化镁的结构和性能。结果表明,在改性剂添加量(改性剂与纳米氢氧化镁的质量比)为0.6时,纳米氢氧化镁的表面性质由亲水疏油转变为亲油疏水,新型纳米聚丙烯酸酯乳液与纳米氢氧化镁粒子表面发生了化学反应,并包覆在其表面,达到了较好的改性效果。对比了其他传统型硅烷偶联剂对纳米氢氧化镁的改性效果,结果表明新型聚丙烯酸酯微乳液改性的纳米氢氧化镁的分散性和疏水亲油性都要优于传统型硅烷偶联剂的改性效果。 相似文献
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研究了纳米Fe2O3,有机表面改性的影响因素,确定了最优改性剂和改性条件。采用红外光谱(FT-IR)、热分析(TG)、透射电镜(TEM)和分散性实验对表面改性前后的纳米Fe2O3,进行了表征。实验结果表明,以硬脂酸为改性剂、用量为15%、pH值为8、改性时间为2h时,改性后的纳米Fe2O3的亲油化度达到89.47%。红外光谱和热分析显示,硬脂酸以化学键合的方式结合在纳米Fe2O3的表面,其质量分数约为11%。透射电镜(TEM)和分散性实验表明,经硬脂酸有机表面改性的纳米Fe2O3,具有亲油疏水性能,能较好地分散于有机溶剂二甲苯中。 相似文献
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Xiaoying Zhang Wenya Wen Hanqiang Yu Fengxian Qiu Qian Chen Dongya Yang 《Journal of Polymer Research》2016,23(4):75
A series of fluoroacrylate (FPA) and nano-silica/fluoroacrylate were prepared. The properties including physical properties, mechanical behavior and contact angle of FPA were investigated. According to the results, the optimal fluoride content can be screened. The nano-silica/fluoroacrylate (SiO2/FPA) materials were characterized by fourier transform infrared (FT-IR), thermogravimetric analysis (TGA) and transmission electron microscope (TEM). The surface morphology and mineralogical analysis of the stone samples were characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD), respectively. The prepared coating was selected to protect on the stone surface. Aimed at evaluating the coating performance, the protective performances were also evaluated by artificial aging test. The results indicated that when the content of hexafluoro-butyl methacrylate (HFMA) was 8.0 wt% and the content of SiO2 was 4.0 wt%, the prepared material has good compatibility and appearance with stone relics. The protective coating material for protection of chosen Jiaoshan Steles Grove (China) is noticeable and it can be widely applied to the protection of stone relics. 相似文献
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A quaternized ammonium photoinitiator was synthesized via Michael-addition reaction and quaternization reaction, then ion-exchanged
with montmorillonite (MMT). An ordered swollen structure of the intercalated montmorillonite was confirmed by X-ray powder
diffraction (XRD) and thermogravimetric analysis (TGA). UV–vis absorption spectroscopy was employed to investigate the maximal
absorption of photoinitiator and the intercalated montmorillonite. The modified montmorillonite was then mixed with urethane
acylate oligomer (CN964) and tripropylene glycol diacrylate (TPGDA) to form Polyurethane/montmorillonite nanocomposites by
photopolymerization. The photopolymerization kinetics was monitored by real time infrared spectroscopy (RTIR). The X-ray diffraction
and transmission electron microscopy (TEM) results revealed that the modified montmorillonite was exfoliated and dispersed
in parallel alignments as multilayers in the organic matrix. 相似文献
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为实现煤灰渣资源化高效利用,本文以煤灰酸浸提铝后的高硅残渣经焙烧制得的Na2SiO3溶液为原料,采用碳分法制取高附加值的纳米白炭黑。通过单因素法,采用比表面积测试法(BET)、邻苯二甲酸二丁酯(DBP)吸油值测定、透射电镜(TEM)、红外光谱分析(FTIR)、X衍射分析(XRD)等分析表征手段,研究不同的实验条件对制得的纳米白炭黑性能的影响,得到碳分法制取纳米白炭黑的最佳实验工况。实验表明,当硅酸钠溶液中SiO2质量分数为2%、CO2通气速率为0.5/min、溶液反应温度为65~75℃、反应终点pH为8时,通过陈化、过滤、洗涤、共沸蒸馏、烘干后,可得到粒径为20~40nm、DBP吸油值为3.10mL/g、比表面积为250m2/g、质量分数91.88%的性能最优纳米白炭黑。 相似文献
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采用烷基季铵盐类有机插层剂十六烷基三甲基溴化铵(CTAB)对蒙脱土(MMT)进行了改性处理,制备了有机化蒙脱土(OMMT),并对聚丁烯-1热塑性弹性体(PB-TPE)进行了马来酸酐接枝改性(PB-TPE-g-MAH)。以PB-TPE-g-MAH为相容剂,通过熔融插层法制备了PB-TPE-g-MAH/OM-MT纳米复合材料。采用傅立叶变换红外光谱(FTIR)、X-衍射(XRD)、透射电镜(TEM)等手段分析了材料结构。结果表明:OMMT在PB-TPE-g-MAH体系中得到了插层和部分剥离,使有机蒙脱土片层间距由原来的1.96 nm增加到3.81 nm。与不含蒙脱土的PB-TPE相比,PB-TPE-g-MAH/OMMT纳米复合材料的拉伸性能得到明显提高。 相似文献
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Some novel nanocompoites were fabricated via zinc oxide (ZnO) nanoparticles which was modified by 3-aminopropyltriethoxylsilane (KH550) as a coupling agent. Poly(benzimidazole-amide) (PBIA) was synthesized via polymerization reaction of 1,3-bis(5-amino-1H-benzimidazol-2-yl)benzene (3a) with isophthaloyl chloride (4b) and used as a polymer matrix. PBIA/ZnO nanocompoites were characterized by Fourier transform infrared spectra (FT-IR), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and transmission electron microscopy (TEM). FE-SEM and TEM analysis showed that the modified ZnO nanoparticles were homogeneously dispersed in polymer matrix. In addition, thermogravimetric analysis (TGA) data indicated an enhancement of thermal stability of nanocomposite compared with the pure polymer. 相似文献
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H. Iván Meléndez-Ortiz Bertha Puente-Urbina Griselda Castruita-de Leon Carlos Gallardo-Vega Esmeralda Saucedo-Salazar 《Journal of Porous Materials》2017,24(6):1527-1533
MCM-41 mesoporous silicas were covalently modified with polyacrylamide (PAAm) by a novel grafting strategy. The effect of various parameters such as monomer concentration, reaction time, and temperature on the content of PAAm onto MCM-41 silicas were studied. Modified silicas were characterized by X-ray diffraction (XRD), infrared spectroscopy, FT-IR, thermogravimetric analysis, nitrogen adsorption–desorption analyses, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy which confirmed the grafting process. According to XRD, SEM and TEM results, PAAm-modified MCM-41 silica did not show changes in its morphology and mesostructure by comparing with pristine MCM-41. Nitrogen adsorption–desorption studies showed that the attaching of PAAm onto MCM-41 silica decreased the values of pore size, pore volume and surface area. 相似文献
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《Inorganic chemistry communications》1999,2(10):447-449
Nanocrystalline PbSe was synthesized via a sonochemical reaction of Pb(NO3)2 with elemental Se in ethylenediamine under ambient conditions. The sample was characterized by X-ray powder diffraction (XRD), transmission electron microscope (TEM) and elemental analysis. XRD patterns showed that phase-pure PbSe was produced. The PbSe particles were spherical and about 30 nm in size as indicated by TEM observations. The influence of ultrasound and solvent was also discussed. 相似文献
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通过纳米二氧化硅(SiO2)对甲基丙烯酸甲酯-甲基丙烯酸共聚物〔P(MMA-co-MAA) 〕乳液进行了复配改性。采用红外光谱(FTIR)、热重(TG)、X射线衍射仪(XRD)¬、扫描电镜(SEM)对复合乳液的结构和性能进行了测定。结果表明,加入纳米SiO2后使得P(MMA-co-MAA)的聚集态结构发生了改变,造成乳液自脆化形貌发生变化。主要表现为,随着纳米二氧化硅含量的增加,脆片有变大的趋势,同时,收缩卷曲更加明显,提高了P(MMA-co-MAA)的自脆裂剥离性能。这种性能在去除设备表面的放射性污染的废物机械回收中更具备优势 相似文献