Zhi Xiong Huang

Synthesis and Characterization of Soybean Oil Based Unsaturated Polyester Resin

A novel soybean oil monoglyceride based unsaturated polyester resin (SOMGUPR) was prepared using two step polymerization with soybean oil,glycerol,1.2-propanediol,maleric anhydride and phthalic anhydride. FT-IR spectroscopy ,Gel Permeation Chromatography (GPC) and 1H-NMR spectroscopy were employed to study the chemical structure and molecular weight of this unsaturated polyester resin. The results show that 190°C is the optimal temperature to controll the extent of estification reaction.The number-average molecular weight(Mn) decrease with the increasing value of nglycerol:nsoybean oil in SMOGUPR.Also,the side reaction between SOMG and maleric anhydride has not occured as evidenced by 1H-NMR spectroscopy.

Effect of Film Thickness on Structure and Property of Pb(Zr0.53Ti0.47)O3 Thin Film

Pb(Zr0.53Ti0.47)O3 thin films with thickness of 120nm, 190nm, 310nm, 440nm and 630nm were deposited on Pt/Ti/SiO2/Si substrates by sol-gel process through repeating spining process 2 times, 4 times, 6 times, 8 times and 10 times respectively. The structures of PZT films were investigated by SEM and XRD analysis. The ferroelectric hysteresis loops were recorded by Radiant Precision Workstation and dielectric properties were measured using an Agilent HP4294A impedance analyzer. X-ray diffraction indicated that with the film thickness increasing, the diffraction intensity increased. The thickness of PZT film had great effect on ferroelectric and dielectric properties. Conclusively when the film thickness was about 310nm, the PZT thin films possessed better ferroelectric and dielectric properties.

Study on the Synthesis and Properties of EP/PU Composite

Isocyanate-terminated polyurethane was synthesized from polyethylene glycol and toluene disocyantes, which was used to modify the epoxy resin. D-230 was chosen as hardener to produce the PU/EP composite. The structure of composite was characterized by FTIR spectrum. Mechanical properties of the epoxy resin with different PU content were studied. Additionally, damping properties of the PU/EP composite were investigated using DMA, and the results showed that the damping properties of EP evidently improved by blending with PU and with the testing frequency increased, the spectra of tanδ-T shifted to higher temperature.

Experimental Investigation on the Electrical and Dynamic Mechanical Properties of PMN/Electrically Conductive Carbon Black/Butyl Composites

In this paper, a three-phase composite with electrically conductive carbon black (ECCB) and piezoelectric ceramic particles, PMN, embedded into butyl (PMN/ECCB/IIR) was prepared by simple blend and mold-press process. Dynamic mechanical properties with various ECCB loading were tested by dynamic mechanical analysis (DMA). DMA shows that the ECCB loading has remarkable effect on the dynamic mechanical properties of the three-phase composite. The temperature range of loss factor (tanδ) above 0.3 the composite was broadened by almost 100°C and the maximum of loss factor shifts to higher temperature in the testing temperature range respectively with increasing the ECCB loading. The piezoelectric damping theory was used to explain the experimental results. The three-phase composites with proper composition can be used as high damping polymer materials.

Effect of Glass Microballoons Size on Compressive Strength of Syntactic Foams

In this work, syntactic foams made of microballoons having same wall thickness ratio but with different particle size was prepared. Microballoons of three size distribution ranges were selected .The property of the syntactic foams were studied by quasi-static compression test. The experimental results show the microballoons size doesn’t influent the mechanical properties of the syntactic foam significantly. The failure mode of the syntactic foams was also studied in this work.

Preparation and Characterization of Novel Functional Gradient Syntactic Foam

Low density syntactic foam monolayer slices, which were made of epoxy resin matrix and plastic microballoons (MB), were fabricated by rolling process with thickness controlled at 200μm. Density of monolayer slice ranges from 0.500g/cm3 to 0.996g/cm3 and it is designed to fit power law equation. The volume percentage of plastic microballoons in the monolayer pellets varies from 16.61% to 58.06%. The slices were characterized by optical and scanning electron microscopy, and measurement of density and sound wave velocity. The density, glass transition temperature and acoustic impedance were observed to vary with the volume percentage of plastic microballoons in the composite. Graded syntactic foams were fabricated by stacking slices of different density in a sequence of density gradient and the slices were bound together with adhesive made of epoxy resin-hardener under the pressure of 5MPa.

Preparation of Nano Carbon Black/Epoxy Composite by Frontal Polymerization

Frontal polymerization is an fast, energy saving approach to prepare polymers and its composites. nanoCarbon /epoxy composite were prepared by frontal polymerization in this study. The composite was prepared using test-tube, and the reacting front was triggered by hot air gun. It was found that increasing the amount of hardener from 10wt% to 20wt%, the reacting frontal propagating velocity of pure epoxy system increased from 0.11mm/s to 0.34mm/s. With the increasing amount of nanocarbon black, the electrical conductivity of the composite was improved. Along the direction of the frontal polymerization, the conductivity of the composite did not change obviously which indicating the forming of uniform nanocarbon black/epoxy composite by frontal polymerization.

Study on O2 Plasma Surface Modification of Aramid Fiber III

The influence of low temperature plasma treatment on the interfacial performance of aramid fiber was studied. SEM and XPS were used to investigate the surface morphology and the chemical elements of the fiber before and after plasma treatment. The etching degree of the surface of aramid fiber was determined by wettability experiments and tensile/bending measurements before and after low temperature plasma treatment. The result showed that under the condition of 200W/10min/10Pa, the etching effect of the surface of aramid fiber was optimal.The wettability of fiber obviously improved and the bending intensity increased by about 30%.but the tensile performance of aramid fiber did not change much.

Effect of Particle Size on Structure and Dielectric Properties of 0-3 PMN/EP Composite

0-3 PMN/EP composites were prepared with different PMN particle size of powder A(100~154μm), B(74~100μm), C(66~74μm), D(45~66μm) , E(7~35μm) and F(0.15~18μm) by resin casting method. Particle size has great effect on property of PMN/EP composite. SEM analysis indicates that PMN particles with small size dispersed more uniformly in epoxy resin. The dielectric constant and dielectric loss of 0.1PMN/0.9EP and 0.3PMN/0.7EP composites vary a little with the particle size increasing, but dielectric constant and dielectric loss of 0.4PMN/0.6EP increase rapidly. Dielectric frequency characteristics analysis suggest that the variation trend of dielectric constant with different particle size at frequency of 103～106 Hz are almost similar in 0.3 PMN/0.7EP composites, but the dielectric constant of 0.4PMN/0.6EP composite with larger particle size drops remarkably with the frequency increase.

Curing Reaction and Kinetic Parameters of Diallyl Orthophthalate Resin with Initiator Dicumyl Peroxide

The curing reaction of diallyl orthophthalate(DAOP) resin, which was initiated by dicumyl peroxide(DCP), was studied by Fourier transform infrared spectroscopy(FTIR). Differential scanning calorimetry(DSC) was used to determine the curing behavior and kinetic parameters of dicumyl peroxide (DCP) / diallyl orthophthalate (DAOP) system. The results clarified that the curing reaction of DAOP resin could be initiated by DCP at 150-180°C and the reaction heat diffused slowly in curing process. The gel-temperature, curing temperature and thermal treatment temperature of the DCP(3%)/DAOP system were 145.46°C, 166.03°C and 173.83°C. The apparent activation energy, frequency factor and reaction order were 130.200kJ/mol, 5.231×1010 and 0.9455, respectively.