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First we survey the scope and level of research activities in nanoparticle technology (NPT) in ASEAN by looking at relevant international journal publications (2006–2012) in terms of absolute numbers (AN), numbers of publications per million population (PMP) and per billion USD GDP (PBG). Obviously, the statistics show that, within ASEAN, the strength of Singapore covers a wide range of nanotechnology fields and applications, including carbon materials, biosensors, bioelectronics, and pharmaceutics. Malaysia places emphasis on alloys & compounds, carbon materials, and separation technology. Thailand’s emphasis is on molecular modeling, carbon materials, and biosensors. When classification is made on the morphology of nanoparticles mentioned in the titles, the topmost are nanotubes (including CNT, SWCNT, MWCNT) at 392 out of 612 (64.1%), followed by generic nanoparticle/nanopowder and nanofiber (including nanowire, nanorods). Next we look closer at 2 nanoparticle R&D organizations in Thailand, namely, CEPT (CU) and NANOTEC together with their alliances. The interest in nanotechnology of SCG (Siam Cement Group), a leading Thai industrial conglomerate, will also be briefly introduced. .

The novel nanocomposites consisting of fluorinated polyimide (PI) films and zinc oxide (ZnO) nanoparticles, from which green light emission was observed, have successfully been prepared. The embedded ZnO nanoparticles in PI films were prepared by adding two separate zinc compounds in poly(amic acid) (PAA) solution followed by thermal curing to convert PAA to PI. The added zinc hexafluoroacetylacetonate dihydrate (Zn(hfac)) and zinc nitrate hexahydrate (Zn(NO3)2), were converted by thermal decomposition to semicrystalline ZnO nanoparticles, which was confirmed by XRD technique. The green light emission of the nanocomposite films irradiated by UV light was caused by the intrinsic defects in ZnO crystallites. The PI films embedded with ZnO from Zn(NO3)2 emitted much higher fluorescent intensity than their counterparts from Zn(hfac). In addition, the Zn(hfac)/PI film was thermally more stable than the Zn(NO3)2/PI one. From TEM images, the size of ZnO nanoparticles in PI films derived from 28 mol% Zn(hfac) was much larger than those from 59 mol% Zn(NO3)2.

Polyimide (PI) films containing dispersed ZnO nanoparticles were prepared from both zinc nitrate hexahydrate (designated as Zn(NO3)2/PI) and ZnO nanopar- ticles, 2-nm average primary size (ZnO/PI). This work shows how the origin of ZnO affects both the photolumines- cence and thermal decomposition of the film. The presence of ZnO derived from Zn(NO3)2� 6H2 Ow as conf irmed by X- ray diffraction technique. The fluorescent intensities from Zn(NO3)2/PI and ZnO/PI were much higher than that from pure PI films. When the ZnO concentration exceeded a cer- tain saturation level, the emission intensity decreased due to the undesirable aggregation of ZnO. At the same concentra- tion, ZnO/PI exhibited higher emission intensity than Zn(NO3)2/PI. All samples prepared under nitrogen emitted higher intensity than their counterparts prepared under ar- gon. The ZnO/PI film was thermally more stable than the Zn(NO3)2/PI one. From TEM images of 117.6 mol% ZnO/PI films, the ZnO aggregates, whose average size was 17- 90 nm, were well distributed throughout the film but poorly dispersed in nanometer range. 2008 Wiley Periodicals, Inc. J Appl Polym Sci 110: 1921-1928, 2008