聚硅氧烷与纳米SiO_2复合改性光固化水性聚氨酯的制备与性能

以聚碳酸酯二元醇(PCD)和羟基封端的聚二甲基硅氧烷(PDMS)为软段、异佛尔酮二异氰酸酯(IPDI)为硬段,在乳化过程中引入纳米SiO_2,制得光固化水性聚氨酯纳米复合乳液。采用纳米粒度仪、SEM、光学接触角测量仪、电子拉力机等对复合乳液和复合膜的结构与性能进行了表征。研究结果表明:纳米SiO_2相互接触,形成了连续的纳米SiO_2网状结构贯穿于整个聚合物基体中;PDMS与纳米SiO_2的复合引入使复合膜杨氏模量、拉伸强度、断裂伸长率、表面疏水性及耐水性均得到显著提高。     

乙二醇表面改性纳米二氧化钛的制备及其对水性聚氨酯的改性

以乙二醇(EG)和钛酸四丁酯(TBOT)为原料,采用原位表面修饰方法成功制备了乙二醇表面改性纳米TiO2(EG-TiO2);利用傅立叶红外光谱仪、X射线衍射仪、透射电子显微镜表征了其结构,采用热重分析仪测定了其热稳定性.结果表明,经表面修饰的纳米二氧化钛在水性聚氨酯皮革涂饰剂(WPU)基体中分散良好;将EG-TiO2添加到WPU中能显著提高其抗紫外线性能、热稳定性及耐磨性能.     

聚丙烯酸酯改性水性聚氨酯的制备

在回顾聚丙烯酸酯改性水性聚氨酯的研究历史基础上，系统地介绍了聚丙烯酸酯改性水性聚氨酯乳液（PUA）的制备方法，其中包括聚氨酯（PU）和聚丙烯酯（PA）的直接掺混法、PU和PA的乳液共聚法，接枝法，互穿网络法，核壳聚合法，对这些方法做了简单的评述，对其应用范围及前景进行了初步探讨。     

硅氧烷改性水性聚氨酯的制备及性能

A series of novel aqueous emulsion of siloxane modified polyurethane (PU(PE-PSI)) were synthesized based on poly(propylene glycol) (PPG), polyether-grafted polysiloxane (PE PSI), 2,4-tolylene diisocyanate (TDI), dimethylol propionic acid (DMPA) and 1,4 butanediol (BDO) through a direct water emulsification of triethylamine (TEA). The aqueous emulsion was transparent and had a good stability. Fourier transform infrared spectroscopy (FTIR) was used to identify the structure of PU (PE PSI), indicating that the polysiloxane segment had been incorporated with polyurethane chain. Investigation of Electron Spectroscopy for Chemical Analysis (ESCA) and the water contact angle demonstrated that the siloxane migrated to the surface of film. The results also showed that PU(PE-PSI) was still a very good elastomer. With increasing the content of PE PSI, the resistance to water improved and tensile strength increased, while the ultimate elongation decreased slightly for the PU(PE-PSI) film.     

丙烯酸酯改性水性聚氨酯乳液的制备及性能研究

采用共聚的方法制备出丙烯酸酯改性的水性聚氨酯共聚乳液(PUA乳液),并对PUA乳液的制备方法和工艺、耐溶剂性、机械稳定性进行了初步的研究。结果表明,具有IPN结构的PUA乳液耐溶剂性、机械稳定性比水性PU有明显的提高。     

柔性透明自支撑氧化锡锑电纺纳米纤维膜的制备与表征

以四氯化锡和三氯化锑为前驱体,通过静电纺丝技术制备了柔性透明的自支撑氧化锡锑(ATO)纳米纤维膜.研究结果表明,该柔性ATO纤维膜具有四方相金红石晶体结构,且呈无规的纤维网状分布.当前驱体煅烧温度分别为520℃和700℃时,纤维的平均直径为200和150 nm;组成纤维的颗粒的平均粒径为10和19 nm;可见光透过率为72%和80%;电阻率为5.23和2.20Ω·cm.该自支撑ATO纳米纤维膜还显示出优异的柔韧性,在弯曲500次后其电阻率基本不变.     

水性聚氨酯涂料改性研究进展

随着环保理念的日益增长,水性涂料将逐步取代溶剂型涂料.水性聚氨酯涂料由于其综合性能优越,是水性涂料中发展最快的品种之一,得到了广泛研究.为了进一步提高水性聚氨酯涂料的性能,通常要对聚氨酯树脂进行改性.对近些年常用的改性技术,如有机树脂改性、无机纳米材料改性和植物油改性的原理与方法进行了综述.这些改性技术可以提高水性聚氨酯的耐热性、耐水性、光泽度、物理机械性能、固含量等综合性能.     

水性聚氨酯阻燃纳米复合材料的Click反应制备及性能

以4,4'-二羟甲基-1,4-庚二炔功能单体作为扩链剂制备了端炔基功能化聚氨酯, 与叠氮基改性纳米蒙脱土(MMT-N₃)、 纳米氢氧化铝(ATH-N₃)和纳米氢氧化镁(MH-N₃)通过Click反应制备了水性聚氨酯(WPU)阻燃纳米复合材料. 采用红外光谱(FTIR)、 核磁氢谱(¹H NMR)和扫描电子显微镜(SEM)对WPU阻燃纳米复合材料的结构进行了表征, 对比研究了纳米阻燃剂配比和制备方法对WPU阻燃纳米复合材料的氧指数、 动态燃烧行为和热稳定性的影响. 阻燃性能研究结果表明, 当MMT-N₃, MH-N₃和ATH-N₃的质量分数分别为7%, 2%和1%时, 采用Click反应制备的复合材料的氧指数比纯WPU高7%, 点燃时间从10 s延长到29 s, 峰值热释放速率和烟释放速率分别降低了41%和42%. 热失重分析结果表明, 当MMT-N₃质量分数为10%时, 与WPU相比, 采用Click反应制备的MMT/WPU复合材料在热失重50%时的温度提高了21 ℃. 复合材料断面和燃烧后残渣的SEM分析证明在聚合物基体中Click反应是分散纳米材料的一种有效方法.     

纳米TiO_2微球对聚氨酯的改性

采用十六胺作为表面修饰剂,通过一种简单易行的方法成功制备了纳米TiO_2微球.分别利用傅立叶红外光谱仪(FTIR)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)等表征手段对纳米TiO_2微球进行了结构和形貌表征.将制备的纳米TiO_2微球添加到水性聚氨酯基体(WPU)中,测试了其性能.结果表明,纳米TiO_2微球的添加显著提高了WPU的抗紫外线性能、耐水性和热稳定性等.     

水性聚氨酯的制备及其性能的研究

本文以琥珀酸酐与三羟甲基丙烷反应,制得了含有羟基和羧基的酯类亲水性单体,并以此单体与ＴＤＩ和ＰＰＧ－１０００反应,制得了含有羧基的聚氨酯预聚体,在三乙醇胺水溶液中分散得到了水性聚氨酯（简称ＷＰＵ）。本文对预聚体的溶剂种类和用量,对乳胶粒的大小及形状的影响进行了研究,确认溶剂的用量越大,乳胶的粒径就越小;以丙酮作溶剂,乳胶粒为棒状或橄榄球状,而以丁酮为溶剂,得到的乳胶粒为圆球状。通过改变亲水单体的用     

Preparation and Characterization of Water-borne Polyurethane Based on Benzotriazole as Pendant Group with Different N-Alkylated Chain Extenders and Its Application in Anticorrosion

A series of novel anti-corrosive coatings were synthesized successfully. Water-borne polyurethane (WPU) was synthesized using polyethylene glycol and modified by grafting benzotriazole (BTA) as a pendant group (WPU-g-BTA) and N-alkylated amines (ethylene diamine (A), diethylene triamine (B), triethylene tetramine (C)) as side-chain extenders. Fourier-transform infrared spectroscopy, thermogravimetry, and dynamic mechanical analyses were used to characterize the structural and thermomechanical properties of the samples. A gas permeability analyzer (GPA) was used to evaluate molecular barrier properties. The corrosion inhibition performance of WPU-g-BTA-A, WPU-g-BTA-B, and WPU-g-BTA-C coatings in 3.5 wt% NaCl solution was determined by electrochemical measurements. WPU-g-BTA-C coating synthesized with a high cross-linking density showed superior anticorrosive performance. The as-prepared coatings exhibited a very low icorr value of 0.02 µA.cm⁻², a high Ecorr value of −0.02 V, as well as excellent inhibition efficiency (99.972%) and impedance (6.33 Ω) after 30 min of exposure.     

放电等离子烧结制备锑掺杂氧化锡陶瓷研究

<正>透明导电氧化物材料(Transparent Conductive Oxides,TCOs)由于具有高达105S·cm-1的电导率,可见光区域具有80%以上的透过率而在光电子、显示器件、太阳能电池、智能窗领域具有广泛的应用。如向In2O3中添加Sn元素(IndiumTinOxide,ITO),     

Preparation of Tin Oxide-Based Metal Oxide Particles

Tin oxide-doped hybrid particles were prepared by a wet chemical process with organic-inorganic (phenyl/silica) hybrid particles in an alcoholic solution. The phenyl/silica hybrid particles, with a diameter of ca. 790 nm were used as a new support material for tin oxide (SnO₂) particles from tin(IV) chloride. The surface of the particles was modified via nitration of aromatic groups in the particles, to promote formation of the tin oxide coating on the particles. The thickness and surface morphology of the tin oxide layer coated on the nitrated-phenyl/silica hybrid particles could be controlled by varying the tin(IV) chloride concentration and reaction time. The size and morphology of the resultant particles were investigated with field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The particles obtained were also characterised by infrared (FTIR) and solid-state ¹³C magic angle spinning nuclear magnetic resonance (¹³C-CP/MAS NMR) spectroscopy. The effect of processing parameters on the crystallinity and structure of the doped hybrids were confirmed by X-ray diffraction (XRD) patterns.     

锑掺杂二氧化锡实心球和空心球的碳还原制备及其生长机理研究

通过在水平管式炉中用石墨还原锑掺杂二氧化锡(ATO)纳米颗粒的方法制备了ATO的实心球和空心球, 并用EDX和XRD等技术分析了产物的物相和元素组成; 用FE-SEM和TEM观察了其形貌; 用HRTEM分析了其晶格结构. 结果表明, 产物为直径0.2~5 μm的ATO实心球和直径为2~20 μm的ATO空心球. 通过控制Ar流速和沉积位置控制了ATO实心球的尺寸和产量, 用Ostwald Ripening分析了ATO实心球的生长过程. ATO空心球的制备在具有较高氧浓度、长度稍长于刚玉管的陶瓷管中进行, 对其生长机理进行了讨论, 分析了相同条件下使用不同材质的管子生成不同形貌产物的原因.     

Preparation and Characterization of Optically Active Polyurethane from Rotatory Binaphthol Monomer and Polyurethane Prepolymer

Optically active polymers are promising multifunctional materials with great application potentials. Herein, environmentally friendly optically active polyurethanes (OPUs) were obtained by introducing rotatory binaphthol monomer to polyurethane. The influence of binaphthol monomer content on the structure, mechanical properties, infrared emissivity, and thermal insulation of OPUs was studied intensively. Structure characterization indicated that the optically active polyurethanes have been successfully synthesized. The OPU synthesized with BIMOL and BDO at the mole ratio of 1:1 presented better thermal resistance. In addition, OPUs showed enhanced tensile strength and stretchability with the increase of BINOL content to a certain extent due to its rigid structural features and high molecular weight. The optically active polyurethanes showed lower infrared emissivity values (8–14 μm) than waterborne polyurethane (WPU), and the infrared emissivity decreased from 0.850 to 0.572 as the content of the BINOL monomer increased. Moreover, OPU4 exhibited the best heat insulation and cooling ability with about a 7 °C temperature difference. The thus-synthesized optically active polyurethanes provide an effective solution for developing highly effective thermal insulation materials.     

有机硅改性磺酸型聚氨酯/丙烯酸酯复合乳液的制备

将磺酸型聚酯多元醇、异佛尔酮二异氰酸酯（IPDI)和三羟甲基丙烷(TMP)在无有机溶剂参与的情况下进行预缩聚,以硅烷偶联剂γ-氨丙基三乙氧基硅烷（KH550）作为改性剂,加入双官能团单体甲基丙烯酸-β-羟乙酯(HEMA),得到含乙烯基和有机硅封端的聚氨酯作为种子乳液,然后与甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)混合单体共聚,合成了有机硅改性磺酸型聚氨酯/丙烯酸酯复合乳液。 红外光谱的表征确定了有机硅改性磺酸型聚氨酯/丙烯酸酯复合乳液的化学结构;透射电子显微镜观察证实了此复合乳液具有明显的核壳结构;热重分析表明,经有机硅和丙烯酸酯改性后,胶膜的最大热失重温度提高了20 ℃,X射线衍射分析表明胶膜的结晶度降低,有利于提高膜的韧性。 力学性能测试及吸水率测试结果表明,当有机硅含量为1.9%时,胶膜的拉伸强度最高达到25.03 MPa,断裂伸长率为328%,此时膜的吸水率最低。     

聚氨酯改性氟代聚丙烯酸酯的合成、表征与膜形态

在二月桂酸二丁基锡(T-12)作用下,将1,6-已二异氰酸酯(HDI)与聚乙二醇(PEG-200)在70℃反应合成—NCO封端的聚氨酯预聚体(PU),然后滴加甲基丙烯酸十二氟庚酯(RfAA)、丙烯酸羟丙酯(HPAA)和偶氮二异丁腈(AIBN)在甲基异丁基甲酮(MIBK)溶液中聚合反应4～6 h,再经丁酮肟(EtAO)封端,制得了一种新型聚氨酯改性氟代聚丙烯酸酯易去污整理剂(FPUA)。用红外光谱(IR)、核磁共振氢谱(1H-NMR)、核磁共振碳谱(13C-NMR)、原子力显微镜(AFM)和扫描电镜(SEM)等对FPUA的结构、成膜形态及应用性能进行了研究。结果表明:FPUA在亲水性纤维织物和单晶硅表面均能形成非单一结构的疏水膜。该膜附着在纤维表面,能使处理后织物表面水的静态接触角达到146.5°,色拉油的接触角达到132°,且易去污效果良好。