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Low-Density Polyethylene films of 100 μm thickness doped with Eu (TTA)3phen complex was hot-blown by a lab scale extrusion process. The ratio of the complex was varied from 0%, 0.025%, 0.5%, 0.1%, to 0.2% with respect to the total weight of LDPE. The mechanical properties of the films were measured according to ASTM D882, and ASTM D1938 standards. The optical and chemical properties were characterized by spectrofluorometer and FTIR respectively. FTIR characterization shows that Eu (TTA)3phen in LDPE films does not exhibit spectrum due to the dominant nature of amorphous LDPE. All emission transition lines of Eu3+ion for doped films were observed when excited at 394 nm, and the highest peak was detected at 608 nm. The peak intensity reached a saturation level at 0.1% doping ratio, while mechanical test showed that the tensile strength (TS) and elongation at break (EB) of machine direction (MD) oriented films decreased with increasing ratio of the complex, in which at doping ratio of 0.2%, both values dropped by 17.8% and 11.6% respectively.. These results indicate that different doped ratio of Eu (TTA)3phen affect significantly the film properties which offer possibility for an improved photoselective greenhouse plastic films. Keywords; LDPE, Eu (TTA)3phen, Photoluminescence.

Abstract.Polystyrene (PS) nanospheres were synthesized by emulsion polymerization using 2,2′-Azobis (2-methylpropionitrile) (AIBN) as initiator and Sodium dodecyl sulfate (SDS) act as surfactant. The size and distribution of the PS nanospheres were systematically investigated in terms of surfactant concentration. Effect of the surfactant towards to the particle size is study using SEM, FTIR and XRD. It is found that increase in Sodium dodecyl sulfate (SDS) concentration increase the reaction time thus longer time needed for the formation of the nanosphere. However their properties are comparable to the commercial Polystyrene PS nanosphere.

The development of optical fibre temperature indicator using epoxy glue as a detection membrane is presented. This study, investigates the effects of epoxy glue from the reaction of epoxy resin, bisphenol A (BPA) (80-05-7) and adhesive epichlorohydrine (ECH) (106-89-8) as a temperature indicator membrane. In this work the response of epoxy glue to excitation source 395 nm is tested and analyzed under cryogenic conditions. A fiber optic temperature sensor for detecting ambient temperature ranging from 15 °C to 80 °C has been examined. The epoxy glue fluoresce when excited with UV-blue light source. The intensity of the fluorescence of the material decreases when the epoxy glue is exposed to an environment of higher temperature. These decrease level of fluorescence signal has been used to indicate temperature. In this paper, the basic principle of operation, development process and emission response characteristics of this sensor are discussed.

This study reported thermal stability of hybrid sol-gel encapsulation materials doped with lanthanides complexes for generating white light. Red and green lanthanide phosphor, Eu (tta)3phen and Tb (4DBBA)3TPPO were incorporated into VTES:TEOS hybrid sol-gel and dispensed into 360 nm to 390 nm UV LED packages. Thermal properties of developed encapsulation material were analysed by TGA. A thermal aging test up to 96 hours was done to check the stability of developed encapsulation material towards UV LED junction temperature of 120°C and the luminescence properties changes was observed using photoluminescence measurement. To check the encapsulation material stability on forward voltage, the operation voltage has been increased from 3.0V to 4.0V. The photometric measurement were recorded using integrating sphere for the properties of Colour Rendering Index (CRI), colour temperature and Commission Internationale de L’Eclairge (CIE) colour coordinates. Based on the results, developed encapsulation material produced white colour with CIE colour coordinate of (0.32, 0.35), CRI up to 75 and colour temperature around 6000K.