The microstructure and chain diffusion behavior at a rubbery/glassy polymer interface (PS/ PPO) were studied using the depth-resolved technique of secondary ion mass spectroscopy (SIMS). Unlike the typical rubbery-rubbery interface, the microstructure of the miscible glassy-rubbery interface demonstrated a very sharp symmetric profile with a thickness around 25 nm before annealing. As chain diffusion took place, the glassy-rubbery interface moved toward the PPO region, the interface broadened asymmetrically, and the chains diffused across the interface showing both the Fickean and the case II characteristics simultaneously. For the purpose of analysis, the interfacial layer can be divided into a rubbery region and a glassy region according to the local T g calculated from the local polymer concentration using the Flory-Fox equation. The case II characteristic dominated on the glassy side of the interface, where chain mass flow required plasticization of the glassy polymers by the neighboring rubbery chains. The Fickean characteristic, on the other hand, prevailed on the rubbery side of the interface, where polymers at both sides of the interface were rubbery chains. The effect of temperature on the interdiffusion was in good agreement with that predicted by the WLF equation. The average velocity of the interface decreased with the PS molecular weight following a negative power law. The power of the dependence, however, was different for the two molecular weight regimes above and below the critical molecular weight of PS (M c ) 38K). The mutual diffusion coefficient and the tracer diffusion coefficients were determined from the SIMS data. The results were in good agreement with the slow theory predictions.

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Polymer substrates are widely used in the flat-panel-display industry because of their flexibility, light weight, and high power efficiency. However, the lower glass-transition temperatures and thermal stability and higher water/oxygen permeation of cycloolefin copolymers (COCs) constrain their applications in display substrates. In this research, COC/tetraethyloxysilane (TEOS) hybrids were synthesized via a sol-gel process. Differential scanning calorimetry indicated that the glasstransition temperature of the hybrids was higher than that of neat COC and rose significantly as the TEOS content was increased from 1 to 15 wt %. According to an analysis of IR spectra, the fraction of hydrogenbonded carbonyl groups in the hybrids increased as the TEOS content increased. This meant that the interfacial interaction contributed by hydrogen bonds for the COC/ TEOS hybrid system increased as the TEOS content increased from 1 to 15 wt %. On the basis of scanning electron microscopy, the number of dispersed droplets of silica increased as the content of TEOS increased. The decomposition temperatures of the hybrids, investigated with thermogravimetric analysis, were not affected significantly by the addition of TEOS.

A series of organic-inorganic hybrid materials consisting of an organic cyclo-olefin copolymer (COC) and inorganic titania (TiO 2 ) were successfully synthesized by a sol-gel process. TiO 2 was obtained through the hydrolysis of titanium n-butoxide (TNBT) with the catalysis of HCl. Differential scanning calorimetry analysis indicated that the glass-transition temperature of the hybrids was higher than that of pure COC, and it rose significantly as the TNBT content was increased from 1 to 15 wt %. Scanning electron microscopy observations showed that the morphology of fractured surfaces of the COC/TiO 2 hybrid with 5 wt % TNBT was a single homogeneous phase, indicating that the miscibility between COC and TiO 2 was good for the hybrids. According to ultraviolet-visible analysis, the transmittance of pure COC at 550 nm was high up to 91.7%. The light transmittance of the COC/TiO 2 hybrids was still higher than 80% with the TNBT content up to 5 wt %. The decomposition temperatures of the hybrids, investigated with thermogravimetric analysis, were not affected significantly by the addition of TNBT. The oxygen barrier property of the hybrid films showed significant improvements in comparison with pure COC.

With the proliferation of online games and ebooks all over the world, understanding users' intention to play online games through e-book learning has become a new issue for academics and practitioners. Prior studies have investigated the factors affecting learning behavioral intention to play online games. However, little research has been conducted to examine what the gender differences in playing and learning English game-based electronic children's books are. Thus, the aim of this study is to investigate gender differences in the relationships between perceived interactivity, prominence, and congruency related to game-based learning through an electronic children's book designed by our research team. Thirty-two 8-year-old (17 boys and 15 girls) Taiwanese children completed the experiments and questionnaires. Surprisingly, gender differences were predominantly not found in the relationship between factors.