This research presents a study about extrudate swell properties of high density polyethylene melts in annular die extruded in a capillary rheometer through 3 types of annular die: normal annular die convergent annular die and divergent annular die. Each type of die had a die gap of 1mm 1.5 mm and 2 mm respectively. Results of the experiment showed that extrudate swell of high density polyethylene melts occurred in both diameter swell and thickness swell ratio. The swell measured in all 3 types of die tended to be higher with the increase of shear rate and the decrease of 2 mm 1.5 mm to 1 mm die gap by an average of 12%. This occurrence could be explained from measurement of flow properties in all 3 types of die which had increasing shear stress due to the decrease of die gap by an average of 10%. Moreover it was also found that the thickness swell ratio was higher than the diameter swell by an average of 45% in all sizes of die gap. This could be explained from the Stress distribution which was more dense at the mandrels surface when the die gap of annular die decreased.

In this study water quality standard of bottled drinking water distributed in Ang Thong Province was investigated. The results showed that clear plastic bottled drinking water presented completely label information and MFD./EXP. clearly appearance and odourless presented in all samples while Total Dissolved Solid (TDS) of tested clear plastic bottled drinking water samples were in a range of 1±0.00 to 277±0.00 mg/L. Coliform bacteria and fecal coliform bacteria of all tested water samples were less than 2.2 MPN/100 mL and E. coli and total heterotrophic bacteria were not found in all samples. pH values of 18 tested samples were less than 6.5 (60.00%) plastic bottled drinking water samples. Tested opaque plastic bottled drinking water samples showed completely label information and MFD./EXP. clearly appearance and odourless found in all samples while TDS of tested opaque plastic bottled drinking water samples were in a range of 12±0.00 to 13±0.00 mg/L. Coliform bacteria and fecal coliform bacteria of tested water samples were less than 2.2 MPN/100 mL and E. coli and total heterotrophic bacteria were not found in all samples. pH values of 3 tested samples were less than 6.5 (100.00%). Indeed assessment of both types of bottled drinking water samples distributed in Ang Thong Province Thailand based on 6 qualities assessment of standard for drinking water in sealed container set by Ministry of Public Health of Thailand revealed that the tested clear and opaque plastic bottled drinking water samples met the standard for 40.00% and 0% based on pH respectively.