纤维素硝酸酯接枝物的FTIR光谱

作者对纤维素硝酸酯与聚甲基丙烯酸甲酯接枝共聚物的FTIR光谱进行了比较全面的定性与定量分析,并探索其在接枝共聚研究中的某些应用。     

Accessibility and size of <Emphasis Type="Italic">Valonia</Emphasis> cellulose microfibril studied by combined deuteration/rehydrogenation and FTIR technique

We report an FTIR method to measure the accessibility and the size of cellulose microfibrils from the cell wall of Valonia ventricosa. This method is similar to the conventional deuteration technique for measuring the accessibility of cellulosic materials; however, the difference in our method is that the hydroxyl groups O2H, O3H, and O6H in the crystalline region were initially completely deuterated. The sample was then rehydrogenated by soaking in water at 25 °C, so that the OD groups on the surface were rehydrogenated. The ratio of OH to OD absorbance was used to calculate the number of surface vs. core cellulose chains in a microfibril. The obtained experimental ratio of 0.934 was consistent with the value calculated for a previously published 33 × 38 chain Valonia model (Sugiyama et al. 1984). The rehydrogenation process was further investigated by immersing the sample in water at elevated temperatures. At temperatures above 120 °C, rehydrogenation was more efficient, and the efficiency plots vs. rehydrogenation temperature showed two inflection. These points may correspond to the temperature where the cleavage of inter-chain hydrogen bonds and/or crystalline-phase transition would have been occurred.     

红外光谱法研究LB膜中的分子取向

The structure information of orientation and packing of molecular chains can be obtained from infrared transmission and reflection-absorbance (RA) spectra. In the present paper, on the basis of Umemura et al., their FORTRAN program of minicomputer was developed and can be run on 486 personal computer. By comparison of infrared transmission and RA intensities, surface enhancement factors and molecular orientation angle were calculated using the above program, and the influence of complex refractive index, angle of incidence, and thickness of LB film were discussed. These results are consistent with that of Umemura et al.     

Elaboration of ZnO Thin Films with Preferential Orientation by a Soft Chemistry Route

Microcrystalline ZnO films presenting well-defined and tunable orientation were obtained by spin coating of alcoholic sols by two different approaches, based on controlled hydrolysis-condensation of Zn-ethanolamine complexes. As-deposited films are formed by amorphous zinc oxide-acetate submicronic particles, which are transformed into oriented ZnO after thermal treatment. The orientation of ZnO depends on the synthesis method, and the solvent. While in ethanol and [Zn] = 0.05 mol·L^–1, films consist of rectangular platelets oriented with the (100) planes parallel to the substrate (a//n), the orientation of the particles changes to (c//n) for systems in 2-methoxyethanol (2-ME) and [Zn] = 0.75 mol·L^–1. A study of chemical factors that influence the orientation (precursor, solvent, MEA/Zn ratio, concentration, coating parameters, heat treatment) is presented.     

人参种类鉴别的傅里叶变换红外光谱法

用傅里叶变换红外光谱法对白参、高丽参、西洋参、红参、野山参等不同种类的人参进行了鉴别；结果表明，不同种类的人参都具有类同的人参皂苷吸收峰，根据红外指数I值、特定位置的吸收峰峰形以及峰位偏移情况可以很好地鉴别人参的种类；该法简便、实用、可靠。     

红外光谱法研究苯胺和环氧丙烷的共聚机理及共聚物的表征

采用原位红外光谱技术对苯胺和环氧丙烷的电化学共聚机理进行了研究, 研究结果表明, 环氧丙烷能在苯胺及其低聚物阳离子自由基的催化作用下发生α位开环, 与苯胺发生电化学共聚, 生成了含有芳香-脂肪醚结构的共聚物. 采用显微红外成像技术研究苯胺和环氧丙烷共聚物在电极表面的生长特点发现, 该共聚物能在电极表面从中间向两侧有规律地生长.     

Characterization of the molecular deformation behavior of glassy epoxy resins by rheo-optical FTIR spectroscopy

Rheo-optical FTIR spectroscopy was used for the first time to monitor molecular orientation phenomena in highly crosslinked epoxies. After studying the orientation behavior of epoxy/amine networks during uniaxial deformation above their glass transition temperature in a preceding article, this article deals with the rheo-optical characterization of the deformation process of those epoxy systems below T_g. The orientation behavior is influenced by the different molecular structure of the constituents and the free volume entrapped in the resins. Yield strain and tensile modulus are correlated with the slope of the orientation function. The orientation function was found to show an abrupt change of its slope in the yield point region. This phenomenon is discussed with respect to the mechanism of plastic deformation. © 1996 John Wiley & Sons, Inc.     

Molecular deformation mechanisms of isotactic polypropylene in α‐ and β‐crystal forms by FTIR spectroscopy

The orientation behavior of isotactic polypropylene (iPP) in α‐ and β‐crystal form was investigated by rheo‐optical Fourier transformed infrared (FTIR) spectroscopy. This method enabled quantification of the degree of orientation as a feature of structural changes during uniaxial elongation in not only the crystalline phase but also the amorphous one. Molecular orientation mechanisms can be successfully derived from experimental results. Generally, three mechanisms were detected for iPP: (1) interlamellar separation in the amorphous phase, (2) interlamellar slip and lamellar twisting at small elongations, and (3) intralamellar slip at high elongations. The third mechanism was favored by α‐PP, whereas β‐PP favored the second mechanism, which, in fact, was responsible for the different mechanical properties of both materials at the macroscopic level. On the other hand, crystallization conditions may have significantly affected the amorphous orientation. Nevertheless, for both iPP types the chains in the amorphous phase always oriented less than did those in the crystalline phase. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 4478–4488, 2004     

T-Jump/FTIR技术研究3,4-二硝基呋咱基氧化呋咱快速热裂解

采用温度快速跃迁原位池与快速扫描傅里叶变换红外联用(T-Jump/FTIR)技术在0.1-0.4MPa压强范围内研究了3,4-二硝基呋咱基氧化呋咱(DNTF)的快速热裂解.试验是以1000℃·s-1的升温速率在800和1000℃的温度下进行,用快速扫描傅里叶变换红外光谱实时跟踪分析DNTF裂解的气相产物.结果表明,DNTF快速热裂解的主要产物CO、CO2、NO和NO2的相对摩尔浓度c*与温度和压强有关,通过分析相对摩尔浓度比(c*NO/c*NO2)随温度和压强的变化,揭示了DNTF中碳硝基C—NO2存在均裂生成NO2和异构化生成NO两条竞争分解的可能途径,同时压强可能抑制呋咱环和氧化呋咱环生成NO的可能性.压强升高使c*CO和c*CO2升高,而使c*CO/c*CO2下降,证明DNTF的分解中存在非均相的气相/凝聚相反应和均相的气相产物间反应的二次或三次过程.     

几种天然黑色素分子结构的红外光谱表征研究

本文对黑头发、香蕉皮、葵花籽皮、乌贼墨及黑芝麻黑色素进行红外光谱表征研究，考察它们的官能团类型，初步判定黑芝麻黑色素是吲哚 型和邻苯二酚型的混合型黑色素。     

脲醛树脂合成反应过程的FTIR研究

利用傅里叶变换红外(FTIR)光谱研究了脲醛树脂合成中不同结构形成和变化情况. 对FTIR谱图解析和分析的结果表明, 在脲醛树脂预聚物合成过程中, 随着甲醛与尿素反应的进行, 红外谱图特征峰发生有规律的变化, 酰胺II带特征峰波数逐渐低移, 有更多羟甲基、醚键和—NHCH2—结构基元形成, 固化反应使上述结构基元相应减少. 着重分析了不同甲醛与尿素摩尔比(nF/nU)下尿素与甲醛反应产物结构的变化, 随nF/nU的增加, 酰胺II带特征峰波数逐渐低移, 碱性条件下醚键和—NHCH2—结构基元明显增加, 在较强酸性条件下Uron环、亚甲基桥和羟甲基显著增加, 而—NHCH2—结构基元含量下降.     

红外光谱法研究重氮树脂自组装膜的光化学反应

将具有导电功能的聚(4-羧酸钠苯基)乙炔阴离子(PCPA)与具有生物活性的DNA聚阴离子交替与重氮树脂聚阳离子(DR)进行自组装,可以得到层重复单元为DR／DNA／DR／PCPA的三夹层聚电解质自组装膜。重氮树脂聚阳离子在紫外光照射下可与聚阴离子发生光化学反应,使层与层之间的离子键连接转化为共价键连接,从而制备稳定的纳米级超薄膜。本文用红外光谱法对此类聚电解质自组装膜的光化学反应过程进行了研究。     

用醇还原VOPO4·2H2O制备的VOHPO4·0.5H2O的择优取向性能

 研究了用醇还原VOPO4·2H2O制备的VOHPO4·0．5H2O的晶面择优\r\n取向现象及其在正丁烷和空气混合气体中活化后,产物（VO）2P2O7的\r\n晶面择优暴露对正丁烷氧化制顺酐性能的影响．以伯醇还原VOPO4·2H\r\n2O制备的VOHPO4·0．5H2O晶体,晶面择优取向于（220）面,晶型为玫\r\n瑰状或扭曲的片状聚集体;活化后的产物仅含（VO）2P2O7相,其（02\r\n0）晶面择优暴露．以仲醇还原VOPO4·2H2O制备的VOHPO4·0．5H2O晶\r\n体,晶面择优取向于（001）面,晶型为平板片状体;活化后的产物由\r\n（VO）2P2O7,VOPO4和无定形相组成,其中（VO）2P2O7相含量低,其\r\n（020）晶面暴露少．由苄醇、环己醇和3－甲基－3庚醇还原VOPO4·2\r\nH2O制备的VOHPO4·0．5H2O的XRD谱与用仲醇制备的相似．用一般方法\r\n（V2O5／异丁醇／H3PO4）制备的VOHPO4·0．5H2O晶体不具有晶面择优\r\n取向性质,活化后得到的（VO）2P2O7的结晶度较低．由正辛醇还原VO\r\nPO4·2H2O制备的VOHPO4·0．5H2O经活化后,对正丁烷氧化制顺酐的催\r\n化性能优于用仲辛醇和一般方法制备的VOHPO4·0．5H2O．     

Orientation of uniaxially stretched poly(ethylene naphthalene 2,6‐dicarboxylate) films by polarized infrared spectroscopy

Poly(ethylene naphthalene‐2,6‐dicarboxylate) has been uniaxially stretched at different draw ratios and at two different temperatures below and above its glass transition (T_g ～ 120 °C) respectively, at 100 and 160 °C. Crystallinity has been evaluated from calorimetric analyses and compared to the values deduced by FTIR spectroscopic data. As expected, the obtained results are quite similar and show that films stretched at lower temperature (100 °C) are more crystalline than those stretched at 160 °C. Optical anisotropy associated with orientation has been evaluated by birefringence and show that films stretched at 100 °C are more birefringent than those stretched at 160 °C as a result of a higher chain relaxation above T_g. Polarized FTIR was also performed to evaluate the individual orientation of amorphous and crystalline phases by calculating dichroic ratios R and orientation functions 〈P₂(cos θ)〉 and also show that amorphous and crystalline phases are more oriented in the case of films stretched below T_g. Nevertheless, the orientation of the amorphous phase is always weaker than that of the crystalline phase. Films stretched at 100 °C show a rapid increase in orientation (and crystallinity) with draw ratio and 〈P₂(cos θ)〉 reaches a limit value when draw ratio becomes higher than 3.5. Films drawn at 160 °C are less oriented and their orientation is increasing progressively with draw ratio without showing a plateau. A careful measurement of the IR absorbance was necessary to evaluate the structural angles of the transition moments to the molecular chain axis. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1950–1958, 2007     

Quantitative analysis of near surfaces three‐dimensional orientation of polymer chains in PET and PEN films using polarized ATR FTIR spectroscopy

Polarized attenuated total reflection (ATR) Fourier transform infrared (FTIR) spectroscopy was utilized to characterize the three‐dimensional orientation of polymer chains near highly anisotropic surfaces generated by uniaxial drawing. A versatile method was proposed to analyze the molecular orientation of the polymers by combining the experimental refractive indices and optimized contact pressure by an anvil for solving the optical contact problem. This method is effective even when changes in the molecular orientation along the thickness direction caused by drawing are remarkable. In addition, this method enables quantitative comparison of the molecular orientation among different polymers in the same coordinate system. From the molecular orientation analysis of poly (ethylene terephthalate) (PET) and poly (ethylene naphthalate) (PEN), it was revealed that this method has a broader range of applications with high accuracy in estimating the molecular orientation of polymers compared with the conventional methods. The significant changes in the molecular orientation caused by uniaxial and biaxial drawing of PET and PEN films were quantitatively analyzed, and the reasons for the significant in‐plane orientation of PEN chains on the film plane are discussed. In addition, the difference in the molecular orientation between both sides of the films was also demonstrated. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 870–879, 2010     

大黄的傅里叶变换红外光谱法快速鉴别

利用傅里叶变换红外(FTIR)光谱法对不同的大黄药材进行了分析?结果表明：大黄样品在4000～1800cm^-1区域有相似的红外光谱特征,而在1800～400cm^-1区域不同组系、不同品种的样品又存在很大差异。因此红外光谱法可以快速、简便、直观地对中药材进行质量鉴别。     

氨基聚酯树脂固化过程的FTIR跟踪

用FTIR内标法跟踪氨基聚酯树脂的固化过程,选取815cm~(-1)的三嗪环面外振动峰作内标峰,913cm~(-1)处的甲氧基变形振动峰和3500cm~(-1)左右的羟基伸缩振动峰为特征吸收峰。结果表明,随着固化的进行,涂膜的羟基、甲氧基和羧基递减,醚键和羰基递增,说明固化过程是以交联反应为主,伴有自缩合反应和酯化反应的复杂过程。     

The FTIR study of uranium oxides by the method of light pipe reflection spectroscopy

Light pipe infrared reflection spectra of UO₂, UO₃, U₃O₈ have been studied by using an FTIR spectrometer. The uranium oxide powders were ground to ensure fine particle size and distributed on the inner surface of a straight glass pipe with gold coating. The infrared beam from the interferometer was focused into one end of the pipe at 45° incidence and then the transmitted beam was refocused by a pair of Cassegrainian type mirrors. The resultant spectra show the infrared characteristics of the -U-O-U-O-, uranyl ion UO ₂ ²⁺ bond vibration and the active lattice vibrations predicted by group theory calculations. In comparison to the transmission spectra measured by authors or reported in literature, this 45° incident light pipe method as well as the previous light pipe method offer advantages of sensitivity, ease of acquisition and interpretation, and require a very small sample. It confirms the power of the light pipe method for studying powders and its special utility for the infrared studies of hazardous materials.Visiting from the Physics Department, Peking University, Beijing, People's Republic of China     

电化学现场时间分辩FTIR反射光谱和程序电位阶跃暂态响应信号同步检测系统

应用弛豫（或暂态）方法研究电极过程动力学始于五十年代。由于通过对暂态实验数据的解析能够获得反应速度常数、扩散系数、传递系数、交换电流密度等参数,从而唯象地描述电化学反应动力学,这一研究领域至今仍然十分活跃。从八十年代发展起来的电化学现场红外光谱为研究电化学反应机理提供了分子水平上的数据,从而深化了对速度控制步骤等细节的认识。近几年来我们通过发展时间分辨电化学现场ＰＴＩＲ光谱和程序电位阶跃技术成功地在分子水平上研究不可逆电化学反应的动力学,获得中间体或产物的生成速率。显然,结合时间分辨红外光谱的信息和程序电位阶跃获得的数据将对电化学反应的机理和动力学有更深刻的认识．迄今为止,这两类研究都是分别进行的．时间分辨红外光谱必须使用“薄层电解地”,而暂态方法则应用常规的电解池,这导致了实验条件的不一致,从而对实验数据解析产生分歧．理想的解决办法是两种研究方法都使用同一红外“薄层电解池”,并且同步检测电化学反应体系的电响应（电压、电流）和光响应（红外光谱）信号．本文报道了我们建立的同步检测系统,并通过研究甲酸在Ｐｔ电极上的氧化过程对该系统进行检验,实验结果同时显示了红外“薄层电解池”的快速响应特性．     

用原位红外光谱研究低硅铝比ZSM－5沸石中的新型B酸

在反应条件下付里叶变换红外光谱技术的研究，揭示了高晶格铝含量（每结构单元含７．６８个铝）的沸石ＺＳＭ－５有新类型的Ｂ酸．基于甲醇和甲醇脱水物二甲基醚与Ｂ酸的相互作用，在红外差谱中，原来表征Ｂ酸在ＯＨ伸缩频率区的特征吸收谱带３６１０ｃｍ－１不再出现，代之以两个负吸收谱带，分别为３６１５与３５８５ｃｍ－１，这是以往的研究中未报导过的红外吸收谱带．这个实验事实支持了Ｈａｗ根据１ＨＭＡＳＮＭＲ结果提出的有第二种Ｂ酸存在的可能性