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Polysaccharide from traditional Chinese herb, Saposhnikovia divaricata (Turcz.) Schischk. (SD) was extracted, fractionated and characterized in this work. Four fractions were prepared. Their molecular weight, monosaccharide compositions, linkage modes and structural properties were characterized with SEC-MALS-RI, HPAEC-PAD, GC-MS and NMR. SDP1 was assigned as a 1, 4-α-glucan with small amount of O-6 linked branches. SDP2 contained a big amount of the 1, 4-α-glucan and a small amount of arabinogalactan, while SDP3 possessed relatively lower amount of the 1, 4-α-glucan and a big amount of the arabinogalactan. SDP4 was defined as a pectic arabinogalactan. Four fractions showed antioxidant activities in both molecular and cellular levels and their activity was ranked as SDP4 ≈ SDP3>SDP2>SDP1. The 1, 4-α-glucan in SDP1 had the weakest, while SDP3 and SDP4 showed similar and the highest antioxidant activity. The arabinogalactan was the major component of both SDP3 and SDP4, which significantly contributed to the antioxidant activity of SDP.

A series of wear and flame resistant polyamide 6 (PA6) composites were prepared using glass fiber (GF) and talc (T) as reinforcer, polytetrafluoroethylene (PTFE) and graphite (Gr) as solid lubricants, red phosphorus (RP) and zinc borate (ZB) as flame retardant. The tribological property, mechanical property, flame retardant property and the flame retardant mechanism were investigated. The tests show that the formula of the wear resistant PA6 composite (WRPA 6) is PA6/GF/T/PTFE/Gr in the ratio of 100/15/5/10/5 by mass. Because this composite exhibits the lowest friction coefficient (0.1429) and no wear mass loss, the introduction of RP and ZB can increase the flame resistance of WRPA6, and the synergistic effect of RP and ZB is obtained. Detailedly, the composite with 4 parts of ZB and 12 parts of RP shows the best flame retardant property, achieving the highest limiting oxygen index (LOI) (30.2 vol%) and a UL94 V-0 rating, and the flame retardant mechanisms may be gas phase along with condense phase mechanism.

The reaction injection moulding process was employed to prepare montmorillonite (O-MMT)/polyamide 6 (PA6) nanocomposites. O-MMT was functionalised by aminosilane in order to improve the compatibility and decrease the viscosity of caprolactam melts, which swell O-MMT. Small angle X-ray diffraction and transmission electron microscopy results demonstrated that PA6 was sufficiently polymerised via in situ anionic ring opening route at the interlayer of the premodified O-MMT that yields a disordered exfoliated structure. Wide angle X-ray diffraction, polarising optical microscopy and differential scanning calorimetry analysis indicated that the crystallinity of nanocomposites decreased as the loading of O-MMT increased. O-MMT can induce γ-phase crystals and eliminate perfect α-phase crystals into smaller imperfect crystals. The O-MMT primarily disperses in the amorphous phase of RIM PA6 matrix that improves the mechanical properties and heat distortion temperature (HDT) of nanocomposites. For the nanocomposit...

The tribological properties of nano titanium dioxide filled polyamide 6(TiO 2 /PA 6 nanocomposite, 5/95 by weight) and its composites filled with single and combined solid lubricants were systematically investigated. It was found that all the solid lubricants except molybdenum disulfide (MoS 2 ) could significantly enhance the tribological performance of TiO 2 /PA 6 nanocomposite; and the nanocomposite filled with polytetrafluroethylene (PTFE) exhibited lower friction coefficient and wear rate than that filled with ultra-high molecular weight polyethylene (UHMWPE); but it was interesting that the nanocomposite filled with MoS 2 combined with UHMWPE had better tribological performance than that filled with MoS 2 combined with PTFE, and the nanocomposite filled with MoS 2 together with both UHMWPE and PTFE performed the best among the combination solid lubricants. XPS and SEM results showed that the synergism of fillers in helping the formation of thin, uniform and continuous transfer film was responsible for the enhancement in tribological properties.

Self-supporting pH-responsive micro porous membranes from Copolymer PVA-co-PDEAEMA were prepared via curtain coating process. The morphologies of the micro porous membranes were investigated by polarized optical microscopy. The above polymers were shown to form self-supporting membrane systems that were able to react on pH stimuli in terms of water flux.

The biodegradable microcapsules based ethyl cellulose (EC) for a controlled delivery of Argy Wormwood solution (AWS) were prepared by emulsionsolvent evaporation method using ethyl acetate as solvent. This study examined the effect of the ratios of core to shell on the size of microcapsules. SEM images of microcapsules showed uniform spherical structures with smooth surfaces with a particle size distribution of 100nm2μm. Core-shell, hetero-structures were confirmed using optical micrograph. The chemical structure of the microcapsules was determined by FTIR.

The key parts of multi-function and all-electric rheometer (MAR) designed by the authors were introduced. The data processing method based on frequency-domain analysis were established. Intrinsic vibration displacement is defined to eliminate the effect of steady velocity displacement and extract the useful information of vibration displacement. The actual frequency, amplitude and phase of the superimposed vibration displacement and the entrance pressure were obtained by the frequency-domain analysis of the intrinsic vibration displacement and the entrance pressure. The control precision of the superimposed vibration displacement frequency and amplitude of MAR proved to be high. The direct current component of entrance pressure can be seen as the mean entrance pressure which stands for the flow resistance. The study of mean entrance pressure is useful in discovering the energy consumption mechanism of the polymer processing introduced vibration energy. Loss angle can be calculate according to the phase of entrance pressure and superimposed vibration displacement. The higher order harmonic of the entrance pressure can be used to characterize the nonlinear viscoelasticity of polymer melts. The factors which depend on the shear rate and influence the viscoelasitic properties can be studied by test the loss angle based on MAR.

A new hyperdispersant agent with maleic anhydride monoester as anchoring group, butylmethacrylate as solventable chain, and styrene (St) as functional group was synthesized, and named SMB. Also, the effects of nanometer-TiO2 (nano-TiO2) modification and concentration on the mechanical properties of polypropylene/polyamide/maleic anhydride-grafted polypropylene (70/30/5 by weight) composites were investigated. The experimental results indicated that the mechanical properties of polypropylene/polyamide 6/M blend reduced with the addition of p-TiO2 (unmodified nano-TiO2) due to the aggregation of nanoparticles, but improved by the addition of t-TiO2 (modified by titanate coupling agent TDI) or SMB-TiO2 (modified by hyperdispersant agent SMB), and SMB-TiO2 seemed to be more effective. The optimum content of SMB-TiO2 was found to be 3 wt%. In order to understand the reinforcing mechanisms of nanoparticles, SEM and TEM pictures were carried out, which revealed that SMB-TiO2 mainly distributed at the interface of polypropylene and polyamide 6 in nanoscale as compatibilizer. It could be due to the surface of nano-TiO2 coated with SMB, and the carboxy group of SMB could react with the functional group of PA6; meanwhile, the solventable chain had good compatibility with PP, and so the interaction between PP and PA6 increased in the presence of SMB-TiO2. Consequently, PP/PA6/M blend could be simultaneously strengthened and toughened by SMB-TiO2.

A simple, cheap and environmental double thin super-hydrophobic composite film was prepared on the surface of tinplate by a simple casting method. The contact angle and sliding angle were measured by an optical contact angle meter. And the major factors that influenced the super-hydrophobic effect of the composite film were studied in our work. The results showed that when the melting temperature was 120°C, the weight radio of PP and PP-g-MAH was 1:4, the drying time was 24h, the dosage of ethanol was 0.4ml, the composite film showed a satisfactory super-hydrophobicity and its water contact angles reached a maximum value of 156.6° while the sliding angle reached a minimum value of 2°. Because of anti-oxidation, moisture-proof and anticorrosion performance of super-hydrophobic tinplate, it has potential practical applications in packaging material engineering.

Polyamide 6-polyurethane (PA6-PU) block copolymers filled with graphite particles were prepared by anionic polymerization process. The friction and wear experiments were conducted using a UMT-3 machine with the chromium steel ball sliding on surface of the composites at high sliding speeds of 500rpm, 1000rpm and 1500rpm and loads of 78.5N and 157N. With adding of graphite, coefficient of friction and wear rate values of the composites decreased firstly, and then increased. And the influence of the applied load and sliding speed on tribological properties of the composites was explored in this study. The results showed coefficient of friction and wear rate values increased with the increasing of load. Coefficient of friction decreased and wear rate values increased with increasing of sliding speed. Microstructure of wear surface of the tested composites was inspected by scanning electronic microscope(SEM) and wear mechanism of the composites was studied.

Polyamide 6/polyurethane/graphite composites have been prepared by anionic polymerization process. The effect of graphite concentration on mechanical properties of the composites was investigated. The test results show that with increment of graphite content, tensile strength of the composites increases firstly, and then decreases, while notch impact strength decreases. The change of mechanical properties of the composites is attributed to the dispersion of graphite, the interfacial properties between the matrix and graphite and the nucleation effect of graphite. In addition, the relationships between loss factor(Tan δ), storage module(E’) and temperature were investigated using Dynamic Mechanical Analysis(DMTA), and the morphological characteristic of the composites were studied using Scanning Electronic Microscope (SEM).

A computer simulation model was established to analyze the curing and cooling of reaction injection molding process of nylon 6 based on theory of balance equation of energy, reaction kinetics and crystallization kinetics. The reasonable assumptions and simplifications were introduced in the model, and an explicit finite difference method with MATLAB software was applied to calculate and predict the conversion and temperature distribution within a plate type mold. The results show that the center position reaches the peak temperature about 45s. The effects of the feed temperature, wall temperature, and reaction rate constant on the temperature and conversion were discussed for searching the optimum processing conditions. The results suggests that the effect of reactive rate on crystallization, molecular weight and phase structure is decided by the value of reaction constant; the influence of the mold wall temperature on reactive rate and temperature near the boundary was great; and the control of feed temperature is important in condition of low mold temperature.

A novel carbazole-based compound 5 , 3,6-bis[( N -ethylcarbazole-3-yl)-propene-1-keto]- N -ethylcarbazole has been designed, synthesized and characterized. The absorption and fluorescence spectra in solvents of different polarities prove that the compound has a distinct intramolecular charge transfer character. Compound 5 can be used as a new class of fluorescent probe or biosensor due to its sensitivity to the local microenvironment such as solvent polarity.

New layered perovskite compounds, Ag(subscript x)Na(subscript 2-x)La2Ti3O10 (x=0.2, 0.3 and 0.5) were synthesized by an ion-exchange reaction of Na2La2Ti3O10 with AgNO3 solution and characterized by energy dispersive X-ray analysis(EDX), X-ray diffractometry(XRD), scanning electron microscopy(SEM) and X-ray photoelectron spectroscopy(XPS). The ion-exchange processes were optimized, and the antibacterial activity, light permanency and water-resistance were evaluated. Surprisedly, no significant changes in crystal structure of Na2La2Ti3O10 are found by the exchange of silver ions. The Ag0.3Na1.7La2Ti3O10 particles conglomerate obviously with irregular shape and size. Ag0.3Na1.7La2Ti3O10 possessing the minimum inhibitory concentrations(MICs) against Escherichia coil (E. coli), Staphylococcus aureus (S. aureus) of 180mg/L and 240mg/L, has high antibacterial activity, good light permanency and water-resistance. The ionic state silver in Ag(subscript x)Na(subscript 2-x)La2Ti3O10 is the antibacterial active component.

In the present work, N2, N2 + H2, Ar and Ar + H2, were used as the sintering atmosphere of Metal Injection Molded 316L stainless steel respectively. The influences of the sintering atmospheres on C, O, N contents of the sintered specimens, sintered density, grain morphology and mechanical properties were investigated. The results show that C, O, N contents of the sintered specimens can be controlled in permitted low values. The ultimate tensile strength and elongation of the specimen sintered in N2 + H2 atmosphere are 765 MPa and 32% respectively. Using Ar and Ar + H2 as the sintering atmosphere, the density of the sintered specimens is 98% of the theoretical density; the pores are uniformly distributed as small spherical shape and the grain size is about 50 µm. The mechanical properties of the specimen, i. e. ultimate tensile strength 630 MPa, yield strength 280 MPa, elongation 52%, HRB 71, are much better than those of the American Metal Powder Industries Federation (MPIF) 35 Standard after being sintered in Ar + H2.

Large-area self-assembly of rubrene has been fabricated on Au(111) surface and studied by scanning tunnelling microscopy. The rubrene monolayer on Au(111) surface is characterized by well-ordered row-like structures similar to the a – b plane of rubrene single crystal. However, the directions of the neighboured molecular rows are opposite to each other. In a two-layer film of rubrene on Au(111) surface, the arrangements of the top molecular rows are determined by the underneath rows, suggesting an orthorhombic crystal structure with a = 1.26 nm, b = 4.36 nm, c = 0.17nm for multilayer of rubrene on Au(111).