二氧化钛包覆空心玻璃微珠隔热涂料

以Ti(SO4):溶液为前驱体,NH3·H2O为沉淀剂,在20～100℃、pH值为3～9的条件下,采用非均相沉淀法对空心玻璃微珠进行包覆.用XRD测试粉体的物相组成,用SEM分析晶体形貌.以这种包覆材料作为填料制备隔热涂料,并对其隔热效果、基本性能进行了研究.结果表明:pH值7、反应温度为55℃条件下,空心玻璃微珠表面均匀包覆一层锐钛型TiO2,以其作填料所制备的涂料具有良好的隔热效果和施工、使用性能,应用前景十分广阔.     

空心微珠表面包覆TiO2的研究

在采用加碱法空心微珠表面包覆TiO2,适宜的工艺条件是反应温度70～80℃,体系pH值2.0～2.5,加料时间控制在4～5 h,搅拌速度400r/min,得到的样品经过950℃,2 h煅烧处理.指出提高空心微珠包覆率和保证包覆尽量均匀是影响涂层降温效果的关键.     

包覆空心玻璃微珠复合型隔热外墙涂料的研制

以BS43N乳液及有机硅氧烷改性丙烯酸酯共聚物乳液为基料,以钛白粉为颜料,以红外粉、包覆空心玻璃微珠等为填料,在助剂的配合下,制备了隔热外墙涂料。对空心玻璃微珠包覆前后外貌进行了电镜分析,并对乳液配方进行优化试验,确定了最佳配方。结果表明:选取m(BS43N)∶m(有机硅氧烷改性丙烯酸酯共聚物乳液)=(4∶6)～(5∶5)的比例制备的涂料效果较好,涂料耐沾污性、透气性、隔热性都有明显提高。     

新型橡胶填料--空心玻璃微珠

空心玻璃微珠对我国橡胶工业而言，还是一种新填料。研究空心玻璃微珠的表面特性和表面处理效果，探讨了空心微珠在炭黑增强橡胶中的应用。结果表明：空心玻璃微珠表面的羟基含量很低，含水量很小，不利于进行改性程度高的表面处理。空心玻璃微珠的粒径有一定的分布。使用硅烷偶联剂进行表面处理后，能够使微珠的表面由亲水变为亲油，并在一定程度上提高其补强性能。空心微珠可以在完全不改变原有配方的基础上，进行较大量填充。单独使用不如与炭黑、白炭黑并用，复合材料的主要优势在于：成本较大幅度地下降，各项力学性能保持较好，随微珠用量的增加，加工性能和产品的外观进一步改善。     

空心玻璃微珠的应用研究现状

文章综述了近年来空心玻璃微珠的应用研究进展,包括在复合材料、石油化工、航天航空、涂料、医药等领域的应用情况。改性后的空心玻璃微珠可应用电磁屏蔽和吸波材料的制备,拓宽了其应用范围,并分析了其应用前景。     

空心玻璃微珠填充尼龙6的研究

研究了微珠对尼龙6的力学性能和流变等性能的影响,结果表明:填加适量的未经活化处理和活化处理的空心微珠,尼龙6的拉伸强度、冲击强度均随着空心微珠含量的提高而上升;填加少量未活化处理或活化处理空心微珠的尼龙6复合材料熔体粘度随着微珠的加入而下降。扫描电镜结果表明,空心微珠硅氧键上的氧原子与尼龙6氨基上的氢原子间可能存在氢键作用。     

空心玻璃微珠偶联化学镀银的研究

使用氨丙基三乙氧基硅烷偶联剂改性空心玻璃微珠表面,然后直接实施化学镀银,借助红外光谱、扫描电镜和X-射线衍射测试手段对偶联改性效果、镀层表面形貌和结构进行了表征.测试结果表明,与胶体钯活化法和硝酸银活化法化学镀银相比,空心玻璃微珠偶联表面改性直接化学镀银的镀层更为致密、均匀,银利用率高,导电性好,结合力强.     

空心玻璃微珠增韧高密度聚乙烯

采用悬臂梁缺口冲击、DSC、SEM 等方法研究了空心玻璃微珠(HGB)用量、粒径大小、偶联剂处理和基体韧性等因素对高密度聚乙烯(PE-HD)/HGB 复合材料冲击强度和热性能的影响。结果表明:复合材料的冲击强度首先随 HGB 含量的增加而增大,当 HGB 用量超过一定值后,冲击强度又随 HGB 含量的增加而减小。HGB 的粒径越小,增韧效果越好,当粒径较大时,增韧作用不明显。偶联剂可以明显改善 HGB 在基体中的分散,进而达到较好的增韧效果。对于 PE-HD/HGB 复合材料,要求基体的最低冲击强度为5.2 kJ/m~2。     

空心玻璃微珠增强聚丙烯材料的性能研究

研究了空心玻璃微珠填充改性聚丙烯的力学性能和热性能.结果表明,空心玻璃微珠的加入,可使聚丙烯的密度、拉伸强度、冲击强度等力学性能下降,弯曲强度、维卡软化温度呈上升趋势.     

Preparation and thermal reflectivity of nickel antimony titanium yellow rutile coated hollow glass microspheres composite pigment

In order to reduce the urban heat island effect, nonwhite lightweight pigments with high near infrared reflectance were studied. Nickel Antimony Titanium Yellow Rutile pigments (TiNiY) coated hollow glass microspheres (HGM@TiNiY) with core-shell structure were prepared by a novel mixing slurry-sintering method. The Reflective property of HGM@TiNiY/SR composite coating prepared by mixing HGM@TiNiY with silicone resin (SR) was investigated by an UV–Vis–NIR spectrum analyzer. The results showed that the size distribution of TiNiY particles was from 150 to 450?nm with an average size of 230?nm, and the binding mode of TiNiY particles with HGM and the formation mechanism of TiNiY Shell were discussed. The UV–Vis–NIR reflectance of HGM@TiNiY/SR coating was not only better than that of others filled with HGM powders or TiNiY powders alone but also higher than that of the coating filled with the mixture of HGM and TiNiY powders at the same volume ratio. A possible mechanism of HGM@TiNiY/SR coating on thermal reflection was discussed. This clearly indicates that the pigment of HGM@TiNiY with core-shell structure could be applied as a good colour cool pigment.     

Poly(methyl methacrylate) hybrid syntactic foams with hollow glass microspheres and polyhedral oligomeric silsesquioxanes

The study aims to produce poly(methyl methacrylate) (PMMA)-based lower density syntactic foams with hollow glass microspheres (HGMs) and to improve their mechanical properties by the addition of polyhedral oligomeric silsesquioxanes (POSSs) while maintaining the thermal properties of the neat polymer. First to understand the effect of POSS addition, PMMA–POSS composites with octaisobutyl and octaphenyl POSS were produced through extrusion. Higher relative flexural and impact strengths were obtained with POSS addition to PMMA. Obtaining more enhanced properties with octaphenyl POSS, PMMA-HGM-POSS hybrid syntactic foams were prepared with this additive. In general, the specific flexural strength and modulus of the PMMA syntactic foams were improved with the POSS loading, while the lower density and thermal properties of the PMMA syntactic foams were maintained. PMMA hybrid syntactic foams with 15 wt % HGMs and 0.25 wt % POSS exhibited 37.6% improvement in the specific flexural modulus with respect to the neat PMMA. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48368.     

改性空心玻璃微珠/环氧树脂复合材料力学性能研究

采用偶联剂对玻璃微珠表面进行改性处理,借助超声波振动,使改性空心玻璃微珠在环氧树脂中均匀、稳定分散,增强了玻璃微珠与环氧树脂之间的相容并探讨了改性空心玻璃微珠对环氧树脂力学性能的影响。结果表明,复合材料中改性空心玻璃微珠添加质量分数为3%时,其拉伸强度达到最大值68.54 MPa,与空白样相比提高了20.3%;冲击强度达到最大值24.42 kJ/m2,比纯环氧树脂提高了166%;KIC(断裂韧性)达到最大值2.338 MPa/m2,是空白试样的2.27倍,增韧效果较为明显。     

空心玻璃微球高压贮氢技术

利用炉内成球技术制备的亚毫米量级空心玻璃微球进行实验,系统研究了玻璃微球高压贮氢技术.玻璃微球直径150～250 μm,壁厚0.9～4.0 μm.采用气体渗透法充氢,在高温时,气体扩散进入微球内,温度降低后气体不容易扩散出来,即可实现贮氢.通过控制外界温度和气氛可实现氢气的贮存和释放.对于直径200 μm,壁厚1 μm的空心玻璃微球,在350℃充气的平衡时间约6～10 h,充气平衡后,微球内外压基本相等.在室温条件下,微球的保气半寿命约40～50 d.对于直径200 μm,壁厚2 μm的空心玻璃微球,球内氢气最高压力可达20～25 MPa,单位质量贮氢效率为13%～16％.     

深还原钛渣硫酸法制取钛白实验研究

以含钛铁精矿直接还原冶炼的含钛物料（深还原钛渣）为原料,对硫酸法制取颜料级钛白粉的工艺进行了研究。实验结果表明,深还原钛渣具有良好的酸解性能,酸解率可达97%;酸解后得到的钛液过滤性能好;但酸解钛液中氧化镁和氧化铝浓度过高,所以直接以该钛液为原料制得的钛白颜料性能差。采用深还原钛渣和钛精矿按一定比例混合酸解,可以避免钛液杂质含量过高对最终钛白产品质量造成的影响。深还原钛渣较佳用量为不高于钛原料总质量的20%。     

Electrochemical immunoassay for human chorionic gonadotrophin based on Pt hollow nanospheres and silver/titanium dioxide nanocomposite matrix

BACKGROUND: A new electrochemical immunosensor for human chorionic gonadotropin (HCG) assay was developed based on Pt hollow nanospheres and silver/titanium dioxide nanocomposites. Silver nanoparticles were initially doped into TiO₂ and chitosan (Cs) colloids to form silver/titanium dioxide nanocomposites (Ag? TiO₂? Cs), which had good redox electrochemical activity and excellent film‐forming ability. Then, the free amino groups of chitosan were used to attach Pt hollow nanospheres for immobilization of human chorionic gonadotropin antibody (anti‐HCG) to construct an immunosensor. RESULTS: Cyclic voltammetry and electrochemical impedance spectroscopy (EIS) confirmed consecutive growth of the multilayer films, and transmission electron microscopy (TEM) was used to describe the microstructure of nanoparticles. Optimal response of the immunosensor was obtained at pH 6.5 and 25 °C with an incubation time of 40 min. The immunosensor exhibited a linear range from 0.5 to 250 mIU mL^?1 HCG with a detection limit of 0.26 mIU mL^?1 at three times background noise. The selectivity, stability and repeatability of the immunosensor were satisfactory. CONCLUSION: The strategy showed low‐cost, high sensitivity, broad linear range and fast analytical time. It is expected that the immobilized technique and the detection methodology could be further developed for other proteins. Copyright © 2010 Society of Chemical Industry     

钛液水解工艺对金红石二氧化钛消色力的影响

以工业钛液为原料,采用外加晶种常压水解工艺制备了金红石型二氧化钛,研究了水解钛液的组成和操作参数对二氧化钛消色力的影响。实验结果表明：二氧化钛消色力（Tcs）和蓝相光谱值（Scx）随晶种添加量的增加先增大后减小,随判灰延时时间的增加先增大后减小,随钛液F值的增加先稍有增加后明显降低,随钛液二氧化钛质量浓度的增大而增加。在钛液F值（游离硫酸加上与钛结合的硫酸之和与二氧化钛质量浓度的比值）为1.90左右、铁钛比（铁元素与二氧化钛质量浓度的比值）＜0.5、二氧化钛质量浓度为190~200 g/L、晶种添加量（晶种中二氧化钛质量与对应批次水解浓钛液中二氧化钛质量的比值）为2.0%~2.2%、灰点为“基点+20 min”、熟化时间为0~30 min、稀释水在二沸后100 min加入的条件下进行水解,经过一次洗涤—漂白—二次洗涤—盐处理—煅烧,所得金红石型二氧化钛的消色力更好。     

铁掺杂二氧化钛负载空微球光催化剂制备及应用

采用溶胶凝胶法将TiO_2用Fe(Ⅲ)改性并负载玻璃微珠制得复合光催化剂,探讨煅烧时间、Fe-Ti原子比、煅烧温度等因素对催化性能的影响,确定最佳制备条件,并对其进行表征。结果表明,最佳制备条件:V钛酸丁酯∶V乙醇∶V硝酸∶V去离子水=5∶20∶0.4∶1,Fe-Ti原子比为4%,煅烧温度500℃,煅烧时间2 h。在自然光条件下反应0.5 d,TOC降解率复合催化剂比P25高8.61%。     

表面活性剂对二氧化硅空心微球结构的影响

分别在阳离子和阴离子两种不同类型表面活性剂的存在下,用正硅酸乙酯(TEOS)为硅源包覆纳米尺度的碳酸钙颗粒,去除表面活性剂和碳酸钙,得到了二氧化硅空心微球。用TEM、XRD及低温氮吸附等测试手段对这类材料进行了表征,研究了表面活性剂对样品结构的影响。结果表明,在合成中加入表面活性剂,使二氧化硅空心微球的球壳上出现了介孔相,改善了样品的孔结构。空心微球的BET比表面积为399～898m2/g,明显高于未加表面活性剂的样品。     

Surface energy measurements of coated titanium dioxide pigment

In this study surface energy measurements have been carried out on titanium dioxide pigments coated with different types of organic compounds. The organic coatings investigated were polymethylsiloxane and octyl triethoxy-silane. The level of coating applied was increased from 0.2 up to 1.5 wt%. Contact angles were measured using an advancing sessile drop method. To allow for the fact that measurements were made on pressed discs of particles rather than on a perfectly flat surface, a correction was applied to convert each measured contact angle to the true Young's contact angle. Surface energies were calculated from the corrected contact angles using the Owens and Wendt equation. From the values of surface energy it was possible to determine at what coating level the surface characteristics changed from hydrophilic to hydrophobic and hence when complete coverage had taken place. For both the siloxane and the silane coatings it was found that complete coating coverage occurred at an addition level of around 0.8 wt%. The surface energies of all the coated pigments were found to correlate well with their dispersion behaviour in liquid paraffin.