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.

This research aims to study the application of coconut meal corn cob and durian peel as wood-substituted biocomposites in medium density fiberboard. The fiber: urea formaldehyde glue: isocyanate glue with polymeric diphenymethane diisocyanate type (pMDI) ratio is equal to 1: 0.13: 0.003. The fibers are taken from coconut meal corn cob and durian peel that 7 ratios are used to all of fiber mixing. The fiberboard production use 130°C of temperature with 20 – 50 kg/sq.cm of compressive pressure with 8 minutes per piece of rate. Their fiberboards have 603 – 856 kg/m of density that was tested follow the TIS 876-2547 standard. Resulting the MM33 ratio (coconut meal fibers: corn cob fibers: durian peel fibers is equal to 0.33: 0.33: 0.33) and the CC50 ratio (coconut meal fibers: corn cob fibers: durian peel fibers is equal to 0.50: 0.25: 0.25) can pass the standard in physical properties and mechanical properties. Moreover their fiberboards have good thermal insulation.

The purpose of this research is to improve the physical and mechanicalqualities of natural rubber latex tiles. Water: surfactant: surfactant: 1: 2.75: 0.03: 0.30:0.03: 0.04 by weight and added with natural latex. In the ratio of Portland Cement Type 1: Natural Latex is 1: 0 1: 0.025 1: 0.05 1: 0.075 and 1: 0.10. Formed with compression presses at normal temperatures it was found that the optimum amount of natural latex For concrete reinforced concrete tiles the ratio is 1: 0.025. The tests in accordance with Thai Industrial Standard TIS 535-2556 are tested in 4 aspects. Dimensional stress test Water absorption test And waterproofness testing The value has passed the benchmark. And low thermal conductivity. Increasing the insulation of the roof as well. Can be used as a prototype product tile concrete roof natural latex. To produce commercially And there can be many local latex or rubber latex. To be more useful and valuable.

This research aims to test the properties of concrete block mixed with basalt fragment as aggregates in products. The mix ratios of Portland cement type1 : basalt fragment : water are 1 : 10 : 0.7 1 : 10.5 : 0.7 1 : 11 : 0.7 1 : 11.5 : 0.7 and 1 : 12 : 0.7 by weight. The concrete block samples were mixed and casted in 7 x 19 x 39 centimeter by the concrete block molding machine. The concrete block sample testing follows the TIS 58-2533 standard on non-load bearing concrete blocks. From the results the density compressive strength and thermal conductivity of concrete block mixed with basalt fragment are lower than the common concrete block. In addition the water absorption and volumetric change are higher than the common concrete block. The optimal ratio in this work is 1: 11: 0.7