An effective reinforcement for carbon fiber composites was revealed via the propagation of PAMAM dendrimers on the carbon fiber surface by in situ polymerization. The hierarchical reinforcement significantly improved the mechanical properties of the resulting composites. Functional groups and morphology of the resulting materials were examined by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and atomic force microscope (AFM). Experimental results indicated that dendritic polymer was successfully grown on the fiber surface through the chemical reaction, and this significantly enhanced the interfacial adhesion of resulting composites with supplying sufficient chemical bonding and strong mechanical interlocking. In addition, results of the mechanical property tests showed that interfacial shear strength (IFSS) increased by 90.97%.

The formation process and composition of the acrylonitrile/urea inclusion compounds (AN/UIC) with different aging times and AN/urea molar feed ratios are studied by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). It is suggested that DSC could be one of the helpful methods to determine the guest/host ratio and the heat of decomposition. Meanwhile, the guest/host ratio and heat of deformation are obtained, which are 1.17 and 5361.53 J/mol, respectively. It is suggested AN molecules included in urea canal lattice may be packed flat against each other. It is found that the formation of AN/UIC depends on the aging time. XRD results reveal that once AN molecules enter urea lattice, AN/UIC are formed, which possess the final structure. When AN molecules are sufficient, the length of AN molecular arrays in urea canals increases as aging time prolonging until urea tunnels are saturated by AN.

This chapter contains sections titled: Introduction Mechanism and Equipment of Rheo-optics Rheo-optical Applications for Biopolymers Conclusions References

Completely isotactic polyacrylonitrile (meso/meso triad >99%) has been synthesized successfully by radiation-induced inclusion polymerization of acrylonitrile in urea canals. The long-lived nature of the growing radical species and the linear dependence of molecular weight on conversion were observed. The molecular weight distribution of product polymers was relatively narrow (<1.5). The results indicate that the dual control of the molecular weight and the tacticity for inclusion polymerization of acrylonitrile in urea canals is achieved. In addition, the effect of experimental factors of inclusion polymerization on the isotacticity of product polymers was investigated. It is found that to ensure completely isotactic polyacrylonitrile, the following conditions should be met simultaneously: (1) acrylonitrile monomers are included in urea canals totally before gamma-ray irradiation, (2) the temperature at the chain propagation step is lower than -90 degrees C, and (3) the heat of polymerization is removed effectively.

Completely isotactic polyacrylonitrile (i-PAN) has been synthesized successfully by an improved urea inclusion polymerization. The tacticity of prepared samples were confirmed by 13C nuclear magnetic resonance (NMR), Fourier transform infrared (FT-IR) and X-ray diffraction (XRD).

High-resolution 13C NMR spectra of atactic polyacrylonitrile(PAN) and isotactic-rich PAN were obtained under optimized solution concentration and experimental temperature.Assignments of nitrile carbon atoms with heptads were obtained and shown to be different from previously reported.The methenyl carbon atoms with pentads and heptads were assigned,respectively.It was shown that the atactic PAN obeys Bernoullian statistics.First-order and second-order Markov statistics were applied to calculate the content of the n-ads in isotactic-rich PAN.The number-average lengths of the isotactic and syndiotactic sequences calculated by "block" statistics confirmed the assignments of the heptads by 13C NMR spectroscopy.

Submicrometer zinc oxide (ZnO) with different morphologies including spindle-like, pencil-like, branch rod-like and frizzy flower-like shapes, have been hydrothermally synthesized in mixed solvents of ethanol and water at 140 °C. It was found that the volumes of added ammonia, surfactant (cetyltrimethylammonium bromide, CTAB), and mixed solvent play crucial roles in morphological control of ZnO nanostructures. Increasing the volume of ammonia added to the reaction system, the shape of ZnO evolves from spindle into branch rod-like. Synergetic influence between CTAB and ammonia can only be observed at high concentration of ammonia.

Oriented crystallization of CuSO4·5H2O on a Langmuir–Blodgett (LB) film of stearic acid has been studied in the temperature ranges of 73–68°C and 53–20°C, respectively. This is the first time that the LB film at temperature above its melting point has been served as a template to induce nucleation and growth of crystals. The experimental results demonstrated that the LB film in the liquid state has the ability of directing the nucleation and growth of crystals. Moreover, X-ray diffraction patterns of the as-prepared crystals revealed that the orientation of the attached crystals on the LB film is affected by temperature greatly. The (1¯22) peak is very strong in crystals grown at higher temperature but absent at lower temperature. These results implied that structural changes in the LB film tuned by temperature determine the orientation of the attached crystals. The morphologies of the crystals showed that the orientation changes of the attached crystals influence the shapes and colors of CuSO4·5H2O crystals strongly.

Langmuir–Blodgett (LB) film of stearic acid was used as template to induce the nucleation and growth of KCl crystals when the KCl solution was cooled from 50 to 25°C. When the LB film template was vertically dipped into the solution, only induced crystals with (110) orientation were formed. However, if the template was horizontally placed into solutions, both the induced nuclei at the solution/film interface and spontaneous nuclei formed in solution were simultaneously absorbed onto the LB film, and then grew further to form crystals. X-ray diffraction (XRD) patterns and optical microscopy images showed that the orientation and morphology of the crystals were controlled properly by changing the orientation and position of the LB films in the solutions.

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Mixed LB films of the CT complex of TMB * TCNQ and stearic acid (SA) were prepared. The structures, molecular orientation and morphology of the mixed LB films were characterized by IR, UV-Vis-NIR, XRD and AFM. Our results show that TMB * TCNQ could be deposited on solid substrates by mixing with SA. The complex is mixed-stack, and the degree of charge transfer is 0.35. The chromophore planes of both TCNQ and TMB are perpendicular to the substrate surface and the hydrocarbon chain of SA is inclined at an angle with respect to the substrate surface. There are two kinds of diffraction bands in the XRD spectra, and they probably arise from SA and TMB * TCNQ, respectively. The morphology of mono- and multilayer mixed LB films with molar ratio 1 : 1 consists of many nanorods and particles, and the amount of nanorods and particles increase with increasing the number of monolayers.

Herein we report a new method to collect a qualified infrared spectrum of a solute in solution by two solvent cells with different thickness during background single-beam spectrum scanning. By collecting the background spectrum with two cells (two stages), we successfully achieved accurate solvent compensation between a sample and a reference, namely, the solvent amounts in the sample and background measurements could become congruent. Therefore, the solvent bands were thoroughly suppressed in the infrared spectrum and a qualified spectrum of the solute was obtained.

The dimethylketals of poly(vinyl alcohol), termed polyvinylacetone (PVKA), of moderate ketalization degree in the range from 0.28 to 0.6 exhibited temperature-induced phase transition in aqueous solution, as revealed by cloud point measurements and electron micrographs, which was then further investigated on molecular level using solution-state 1H NMR measurements. The present phase transition is caused by the amphiphilic characteristics in the polymer chain. Moreover, this finding could be further applied as a novel strategy in the syntheses of thermosensitive polymer by the hydrophobic functionalities of linear polyol.

Novel dendritic nanostructures, which are actually self-assemblies of nanoparticles of poly(vinyl alcohol) (PVA) coated Ag and/or Cu2O, were controllably synthesized in an aqueous solution of amphiphilic polyvinylacetone (PVKA) (DH = 0.549), via a one-step in situ reduction of Ag+ and Cu2+ under γ-ray irradiation, using the low hydrolysis rate of the PVKA in the dilute acidic solution. Subsequently, the hydrolysis of PVKA yields PVA chains.

Near infrared (NIR) spectra of 50 powder samples containing acetaminophen and ethenzamide were measured with spectral resolution 1, 4 and 8 cm(-1) respectively, and the calibrations were made from these NIR spectra for the properties of acetaminophen and ethenzamide. The best calibration for acetaminophen, which provides a SEE ( the standard deviation from the property residuum) about 0.20 both for calibration set and validation set spectra, was built with 4 cm(-1) spectral resolutions. Both higher resolution (1 cm(-1)) and lower resolution (8 cm(-1)) spectra provide a little worse calibration results. The above calibration results demonstrate that the spectral resolution has an important effect on the calibration results and the successful application of NIR is highly dependent on the proper selection of spectral resolution.

A monolayer of the charge transfer(CT)complex of TMB and TCNQ has been prepared by the layer-by-layer self-assembled method.Structure and morphology of the complex of the films have been investigated by FT-infrared(IR),ultraviolet-visible-near-infrared(UV-VIS-NIR) spectroscopies and AFM.In the UV-VIS-NIR absorption spectrum,the appearance of a very broad absorption band centered at about 2030 nm in the near-infrared region shows that the mixed-stack CT complex of TMB·TCNQ is formed.In the transmission FT-IR spectrum,the C≡N stretching band in the CT films is observed at 2205 cm~(-1).By the frequency shift of C≡N stretching band,we can estimate that the degree of charge transfer is to be 0.42.The AFM picture of the complex film of TMB and TCNQ shows that its morphology consists of many particles pied up on the plate surface and the sizes of these particles is about 80nm.

Langmuir-Blodgett(LB) films of the mixed-stack charge-transfer(CT) complex of 2-octadecyl-7, 7 8 8-tetracyanoquinodimethane(C(13)TCNQ) and 3,3',5,5'-tetramethylbenzidine(TMB) were prepared. The structures, molecular orientation and morphology of TMB . C(18)TNQ in LB films were characterized by infrared (IR), ultraviolet-visihic-near infrared (UV-Vis-NIR) spectroscopies and atomic force microscopy (AFM). From the UY-Vis-NIR and IR spectra, it could be concluded that the TMB . C(18)TCNQ complex is in a mixed-stacked arrangement style, and the chromophore planes of both C,TCNQ and TMB are nearly perpendicular to the substrate surface. AFM image shows,that the morphology of five-layer LB film of the complex consists of many two-dimensional hexagonal flake microcrystals. The width of these flake microcrystals is about 180 nm.

Water-soluble multiwalled carbon nanotubes (MWNTs) with temperature-responsive shells were successfully prepared by grafting poly (N-isopropylacrylamide) (PNIPAM) from the sidewalls of MWNTs, via surface reversible addition-fragmentation chain transfer (RAFT) polymerization using RAFT agent functionalized MWNTs as the chain transfer agent. Thermogravimetric analysis (TGA) measurements showed that the weight composition of the as-grown PNIPAM polymers on the MWNTs can be well controlled by the feed ratio ( in weight) of NIPAM to RAFT agent functionalized MWNTs (MWNT-SC(S)Ph). The MWNT-g-PNIPAM has good solubility in water, chloroform, and tetrahydrofuran (THF). Transmission electron microscope (TEM) and scanning electron microscope (SEM) images also showed that the MWNT-g-PNIPAM was dispersed individually and eventually bonded with the polymer layer by surface RAFT polymerization. The PNIPAM shell is very sensitive to a change of temperature. This method could find potential applications by grafting other functional polymer chains onto MWNTs.