his research work aimed to study the effects of the addition of sisal fiber and surface treatment by epoxy silane on the physical and thermal properties of polylactic acid (PLA). Specimens of PLA and unidirectional fiber-reinforced composite were processed by a compression molding machine and evaluated the physical and thermal properties by water absorption measurement and differential scanning calorimetry (DSC) analysis respectively. The result showed that water absorption tended to increase by adding sisal fiber whereas surface treatment of sisal fiber by epoxy silane improved water resistance of composites. The water absorption values at immersion time of 5 days were 0.89 1.13 and 1.26 % for PLA PLA/treated sisal fiber composite and PLA/untreated sisal fiber composite respectively. For thermal properties the addition of sisal fiber led to decreases in glass transition temperature and crystallinity. These were because the presence of continuous fiber might interfere with the crystallization of PLA. The surface treatment of continuous fiber with epoxy silane led to difficult crystallization. The good interfacial adhesion interrupted PLA alignment.

Man Lueat (Dioscorea alata) flour is a biopolymer material that can be formed into an edible film. It can be contacted directly with food consumed and naturally biodegraded. The aims of this research were to study the effect of physicochemical mechanical and thermal properties of edible film from Man Lueat flour. The film forming solution was prepared by Man Lueat flour at 4% w/w. The glycerol was used as a plasticizer. It was studied at 3 different levels; 30 40 and 50% w/w of Man Lueat flour. The film forming solutions were formed using the solution casting method and dried at 50 °C for 16 h. Results showed that the glycerol content at different levels of the edible film from Man Lueat flour had no effect on the thickness color transparency and elongation at break. However the moisture content water solubility swelling property and water vapor permeability of the film tended to increase when increasing the glycerol content. In contrast the Young’s modulus and tensile strength of films tended to decrease significantly when the glycerol content increased. Thermal properties were found that decomposition temperature of films occurred 2 stage; the first stage occurs between 50 to 130 ° C and the second stage occurs between 263 to 315 ° C. The analysis of FT-IR showed that the different levels of glycerol affected the structure of the film (3278 cm-1). Therefore the edible film from Man Lueat flour can be applied as a food packaging material to protect the quality of food products.

This research was aimed to study melting behavior of paraffin wax and to evaluate the natural heat convection coefficient of solid cylinder paraffin wax. Two grades of solid paraffin wax; white commercial grade and yellow market grade were studied. Three sizes of flat test tube in diameter 1.5 2.0 and 2.5 centimeters were used. Three different amounts of paraffin indicated from samples’ heights of 5 7 and 10 centimeters were set. The results found the average melting point of both grade paraffin ranged from 44-77 oC. Based on the numerical analysis heat behavior of solid cylinder paraffin at the initial temperature of 50 oC to room temperature of about 30 oC found that natural convection coefficients was ranged from 3 to 9 W/m 2oC. Melting point temperature was found mass independent property while natural convection coefficient declined as the sample’s diameter size inclined

The objective of this research was to study the dominant feature of Khao Wong glutinous rice Kalasin province for geographical indications. The effect of three cultivated areas of glutinous rice variety (RD6) consisting of Khao Wong Huai Mek and Kong Chai districts was investigated along with their physicochemical textural properties and thermal properties. For the effect of different cultivated areas on glutinous rice properties the significant effect of different cultivated areas on chemical compounds viscosity and textural properties was observed (p?0.05). There was no significant effect of cultivated areas on amylose content (p>0.05). The highest protein and ash contents and the lowest setback hardness and chewiness values were found in the sample cultivated in Khao Wong district area. The aroma compounds analysis of rice samples revealed that methanecarboxylic acid was observed in glutinous rice cultivated in all studied areas. Whereas the highest content of 122-Trimethylcyclopropylamine was found in the sample cultivated at Khao Wong and Kong Chai districts. In addition the highest content of 2-cis-9-octadecenyloxyethanol was observed in glutinous rice cultivated at Huai Mek district.