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Five types of amine functional polymer shells were formed on the surface of silica nanoparticles via vapor deposition polymerization and oxidation polymerization. Scanning electron microscopy, transmission electron microscopy, elemental analysis, and Fourier transform infrared spectroscopy have been used to characterize the resulting various types of amine functional polymers coated silica nanoparticles. Electron microscopy studies reveal that the thin polymer shell is successfully formed on the silica surface. The antibacterial performance of the prepared core/shell nanoparticles was investigated against both Gram-positive (Escherichia coli) and Gram-negative (Staphylococcus aureus) bacteria. The various amine functional polymers coated silica nanoparticles presented antibacterial activity against both bacteria. In contrast, silica/PPy core/shell nanoparticles had no bactericidal efficiency, because the amine group of PPy does not provide protonated nitrogen atoms which can kill the bacteria. The obtained results evidence that antimicrobial activity of amine functional polymers is influenced by the state of the amine groups than positively charged amino groups.

Novel PANI nanorods with average diameter of 21–53 nm and length of 0.5–1 μm were synthesized by dispersion polymerization method. The morphology of obtained PANI nanorods was significantly dependent on the type of salt, stirring, and polymerization temperature. Dispersion polymerization with FeCl 3 produced longer nanorods than ammonium persulfate (APS) and magnetic stirring decreased the length of nanorods. While the average diameter of PANI nanorods decreased with increasing reaction temperature, the electrical conductivity dropped considerable at high polymerization temperature due to the increment of insulating emeraldine base. Dynamic differential scanning calorimetry (DSC) study showed that the heat of cure was independent of heating rate. On the contrary, the heat of cure was proportional to the content of PANI nanorods as a role of curing agent. Isothermal DSC study revealed that the cure behavior of LCE/PANI nanorod system was an auto-catalyzed reaction. Thermogravimetric analysis (TGA) indicated that the thermal stability of cured LCE/PANI nanocomposite was significantly dependent on the PANI nanorod composition. In addition, the electrical conductivity of LCE/PANI nanocomposite materials was higher than that of conventional epoxy composites. Therefore, PANI nanorods played a role of curing agent owing to the existent amine group and acted as reinforcing filler for cured LCE nanocomposites.

The biaxially oriented PP/PVA blend film was prepared and had the higher oxygen barrier property by about 130 times than that of a biaxially oriented PP film. When the viscosity ratio (ηd(PVA)/ηm(PP)) decreased, the dispersed PVA phase was developed into platelets during stretching process. Oxygen permeability was dependent on the number and size of PVA platelet. However, the Oxygen permeability was not sensitively changed in above 25 wt% of PVA. To obtain excellent barrier property, the optimum amount of plasticizer and initiator was required. A pasticizer was related to the size and degree of crystallization of PVA platelet. An initiator played the role of a compatibilizer. The oxygen barrier was enhanced with increasing the viscosity of PP and draw ratio. The higher viscosity of PP was advantageous for preventing the delamination of a blend film, and the moisture vapor permeability was not affected with the laminar structure. As a result, the biaxially oriented PP/PVA blend film had the potential of substituting for the PVDC coated BOPP film.

The melting and crystallization behavior of polyvinyl alcohol (PVA) were examined as a function of plasticizer amount. The melting temperature (Tm) of PVA decreased with increasing the amount of glycerin. The effect of a plasticizer rapidly diminished when the phase separation of glycerin in PVA occurred. In addition, the crystallization peak temperature (Tc) of a fully hydrolysed PVA was reduced, and the maximum crystallization rate (Kmax) was retarded, and the crystallite size distribution (ω1/2) was widened. However, the crystallization behavior (Tc, Kmax, ω1/2) of a partially hydrolysed PVA could be disregarded compared with a fully hydrolysed PVA. The thermal history did not affect the crystallization behavior of a fully hydrolysed PVA, but largely affected that of a partially hydrolysed PVA. In a fully hydrolysed PVA / a partially hydrolysed PVA blend system, two Tm peaks appeared, and the concurrent crystallization occurred.

The effects of hyperbranched polymers (HBPs) on the cure behavior of tetrafunctional epoxy resin were investigated using differential scanning calorimetry (DSC) and FT-IR spectroscopy and compared with those of the linear analog. The hydroxyl terminal groups of the HBP initiated the cure reaction through proton donor–acceptor complex. The heat of cure in epoxy/HBP system was higher than that in epoxy/linear polymer system. The activation energy for cure reaction was lower in epoxy/HBP system. When the hydroxyl terminal groups of the HBP were transformed into benzoate groups, the induction time for cure reaction became much longer and the heat of cure was reduced. The isothermal kinetic parameters were obtained from Kamal equation, where the overall reaction order was ca. 1.5. As the cure reaction proceeded, the characteristic peaks of epoxy ring were decreased and H-bonded C O peak was increased. The intensity of the H-bonded C O peak was increased with increasing amount of the HBP.

Polyvinylimidazoles(PVIs) modified with vinyltrimethoxysilane (VTS) in different mole ratios were applied as adhesion promoters for polyimide (PI)/copper interface. The effects of the composition of VTS-modified PVI copolymers on lap shear strengths between PI and copper were investigated at different bonding temperatures. Fourier transform infrared spectroscopy was applied to examine the thermo-oxidative degradation of PI and oxidation of copper. In addition, scanning electron microscope and contact angle measurement analysis were performed to investigate the compatibility of VTS-modified PVIs with PI. An improvement in interfacial adhesion strength was obtained using the adhesion promoters. Especially at higher bonding temperatures, a significant increment in lap shear strength was seen when the mole ratio (VI:VTS) was 3:7, due to the high thermal stability of the silane unit. However, at lower bonding temperatures, lap shear strength does not increase as above, owing to the poor compatibility between the VTS-modified PVI with PI.

The copolymers of vinyl imidazole (VI) and vinyl trimethoxy silane (VTS) were applied as corrosion inhibitors and as adhesion promoters for polyimide/copper system at elevated temperatures. The mole ratios of VI to VTS were 100:0, 70:30, 30:70, and 0:100. Peel test was performed to evaluate the adhesion strength of polyimide/primer/copper system after heat treatment at 400°C in nitrogen atmosphere. The effect of the copolymer composition on corrosion protection and adhesion promotion was investigated by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). The adhesion strength of polyimide/primer/copper system depended on the thermal stability of the primer and the chemical interaction between polyimide and the primer. It showed the highest value when the mole ratio of VI to VTS is 30:70. The primer reduced or suppressed copper oxide formation in the polyimide layer. The degree of corrosion protection by the primer was affected by its thermal stability and its reactivity with copper.

The synthetic process of hyperbranched aliphatic polyesters based on 2,2-bis(hydroxymethyl)propionic acid (AB2-type monomer) and 2ethyl-2-(hydroxymethyl)-1,3-propanediol (B3-type core) was investigated with in situ Fourier transform infrared (FT-IR) spectroscopic analysis. The experimental parameter was the stoichiometric ratio between monomer and core moiety corresponding to theoretical first, second and third generation. In the theoretical first generation, monomers were directly combined with a core molecule. In the theoretical second and third generation, oligomers derived from the reaction between monomers were gradually combined with a core moiety as the reaction time increased. The microstructure of the main product was surmised from the peak integration of in situ FT-IR spectra, the intensity of each repeating unit on 13 C NMR spectra and the number average molecular weight. q 1999 Elsevier Science Ltd. All rights reserved.

The influence of the bridging group between the mesogenic group and the oxirane ring on the curing behavior and the liquid crystalline phase of liquid crystalline epoxy (LCE) resins was investigated. Two LCE resins containing ether and ester bridging groups were synthesized for this purpose. The ether linkage stabilized the liquid crystalline phase of the LCE and the LCE network more than the ester linkage. The retardation effect of curing was observed in LCE with the ester linkage. The LCE with the ether bridge showed higher mechanical and thermal properties than that with the ester bridge. The liquid crystalline phase of the LCE monomer remained after the crosslinking reaction and it was stable up to 300°C.

Two liquid crystalline epoxy (LCE) resins based on biphenol mesogen, BP1 and BP2, were synthesized to produce a highly heat-resistant liquid crystalline network, and the curing behaviour of them was investigated using diaminodiphenylsulfone (DDS) and diaminodipheylester (DDE) as curing agents. The curing rate and heat of curing of LCE resins were measured with dynamic and isothermal DSC. The curing reaction of BP2 based on aromatic ester was faster than that of BP1, and the degree of cure was vice versa. A densely cross-linked BP2 network showed a much higher glass transition temperature (≈280°C) and elastic modulus than other epoxy resins reported up to now. BP2 formed a liquid crystalline network on curing with DDS and DDE, while BP1 showed a liquid crystalline network on curing with DDE. The liquid crystalline phase of the resulting network was maintained up to decomposition temperature (

The copolymer of vinyl imidazole (VI) and vinyl trimethoxy silane (VTS), was synthesized in benzene at 68°C as a novel corrosion inhibitor for copper. The effect of the copolymer composition on copper corrosion protection at elevated temperatures was investigated by Fourier transform infrared reflection, absorption spectroscopy (FTIR-RAS) and scanning electron microscopy (SEM). In addition, an adhesion test was performed to characterize the interface between copper and the polymer film after heat treatment. Corrosion protection capabilities of the copolymer at 360°C in air was improved via increasing the mol ratio of VTS in the feed, due to the improved thermal stability and the reactivity of the copolymer with copper.

Crystallisation behaviours of poly(butylene terephthalate) (PBT) homopolymer and PBT in PBT/polyarylate (PAr) blend have been studied using FT-i.r. spectrometry. In addition, the phase behaviour of the PBT/PAr blend has been investigated using a dynamic mechanical analyser. Several conformational sensitive bands in PBT were investigated using FT-i.r. spectra. The peak of carbonyl stretch mode in PBT shifted to a lower wavenumber and some of the intensities of methylene rocking modes or bending modes increased as crystallisation of PBT proceeded. PAr reduced the crystallisation rate of PBT in PBT/PAr blend. In dynamic mechanical thermal analysis, PBT and PAr were completely miscible in amorphous state, irrespective of the composition of the blend. Crystallisation-induced amorphous phase separation of PBT/PAr blend was detected. Single Tg was observed in all compositions in amorphous state. Different phase separation behaviour was observed in PBT- and PAr-rich blends.

The crystallization behaviour of poly(ethylene terephthalate) in poly(ether imide) (PEI)/poly(ethylene terephthalate) (PET) blends was investigated using Fourier transform infrared spectroscopy. Thin films of PEI/PET blends were prepared by solution blending, and many characteristic bands for the PET crystalline region were observed as a function of the annealing time of PEI/PET blends at 225°C. It was found that the CO stretching band shifted up to 5 cm−1 in PEI/PET blends due to the increase in crystallinity of PET. This CO band shift is in agreement with the increase for the characteristic crystallization band of PET, and the band shift width is proportional to the PET weight fraction in PEI/PET blends. Crystallization of PET occurs immediately by annealing for PEI/PET blends with a high PET weight fraction ( 2 8 and 4 6 PEI/PET blend composition). In the case of PEI/PET blends with a low PET weight fraction ( 6 4 and 8 2 PEI/PET blend composition), crystallization of PET occurs in the PET-rich phase only after the amorphous phase is separated into PET-rich and PEI-rich phases.

Toughened epoxy resins were prepared by dissolving poly(ether imide) (PEI) in the EPON HPT 1071 based resin with EPON HPT 1061M as a curing agent. Open tension tests showed an increase in fracture toughness with PEI content, from 0.61 GPa m 1 2 in the pristine resin to 1.32 GPa m 1 2 at 15 wt% PEI. Similar results were obtained for the flexural properties of the epoxy resin. In order to improve the fracture toughness of epoxy resins, increasing the interfacial adhesion strength between the dispersed PEI phase and tetrafunctional epoxy resin was necessary. Improved interfacial adhesion of the modified epoxy resin was obtained through the hydrolysis of PEI. At a concentration of 5 wt% PEI, hydrolysed PEI/epoxy resin had 40% more fracture toughness than the unhydrolysed PEI/epoxy resin. The effect of PEI hydrolysis on the flexural properties of the cured epoxy resins was also studied. Scanning electron microscopy was used to investigate the relationship between the morphological study of the fractured epoxy resins and mechanical properties of the modified epoxy resins.