The objective of this research is a study to determine optimum forming condition of semi-finished bulk UHMWPE by using ram extruder that obtain maximum yield strength and minimum wear rate for apply to use in area of medical and mechanical application. Experimental extrusion specified forming condition consists of the temperature of 140 150 and 160 ºC and pressure of 3 5 8 and 10 MPa with the temperature exposure time of 30 minutes. After known optimum forming condition of UHMWPE powder thus forming UHMWPE filled with different kind of filler to study and determine optimum weight fraction of various types of filler that affect onto wear resistance property of UHMWPE composites. Result extruded condition at the temperature of 1 5 0 ºC under pressure of 5 MPa with exposure time of 30 minutes is an optimum extruded condition due to specimen shown a maximum yield strength ultimate tensile strength and elongation of 20.43 ± 1.21 MPa 28.33 ± 1.53 MPa and 285.60 ± 6.41 % respectively and obtain minimum wear rate of 3.02  10-9 ± 5.27  10-10 mm3/Nm. Its mechanical properties and wear resistance property higher than imported bulk UHMWPE by 23.3 % and 4.75 times respectively due to the formation of cross-linking are occurred in polymer chain and also its degree of crystallinity is high equal to 61.52%. For bulk UHMWPE IR-spectrum shown a variation peak of carbonyl group (C=O) are occurred that that it indicated the oxidation reaction at the end of polymer chain and tis degree of crystallinity is equal to 53.31% which result to decrease strength of polymer. In the case of UHMWPE filled with filler optimum weight fractions of various types of filler are as follows. 1. The filling of 0.3 wt. % Al2O3 particle size 0.05 μm shown yield strength ultimate tensile strength and elongation of 23.17 ± 3.35 MPa 34.78 ± 2.80 MPa and 229.00 ± 6.09% respectively that its mechanical properties was increased by 18.55% (increasing of ultimate tensile strength). For the wear rate is equal to 2.09  10-9 ± 3.39  10-10 mm3/Nm or its wear resistance was increased by 1.44 times in compared with initial bulk UHMWPE. 2. The filling of 0.4 wt. % Al2O3 particle size 0.3 μm shown yield strength ultimate tensile strength and elongation of 21.93 ± 0.51 MPa 25.40 ± 0.69 MPa and 267.67 ± 22.03% respectively that its mechanical properties was increased by 11.54% (increasing of ultimate tensile strength). For the wear rate is equal to 2.32  10-9 ± 4.78  10-10 mm3/Nm or its wear resistance was increased by 1.30 times in compared with initial bulk UHMWPE. ฉ 3 . The filling of 0.4 wt. % Al2O3 particle size 1 μm shown yield strength ultimate tensile strength and elongation of 23.93 ± 1.89 MPa 26.77 ± 1.20 MPa and 296.54 ± 7.51% respectively that its mechanical properties was increased by 5.83% (increasing of ultimate tensile strength). For the wear rate is equal to 2.14  10-9 ± 3.16  10-10 mm3/Nm or its wear resistance was increased by 1.41 times in compared with initial bulk UHMWPE 4 . The filling of 4 wt. % Al2O3 particle size 5 μm shown yield strength ultimate tensile strength and elongation of 22.57 ± 2.01 MPa 26.31 ± 3.11 MPa and 136.66 ± 11.67% respectively that its mechanical properties was increased by 7.68% (increasing of ultimate tensile strength). For the wear rate is equal to 2.37  10-9 ± 5.71  10-10 mm3/Nm or its wear resistance was increased by 1.27 times in compared with initial bulk UHMWPE

This research work was to study the improvement of toughness and impact resistance of polylactic acid (PLA) with modified soybean oil (MSBO) and palm fiber (PF). The detail of this work was divided into three parts. The first was to find the suitable condition for modification of soybean oil with ozonolysis. The second and last parts were to study the effects of MSBO and PF contents on the properties of PLA respectively. For oil modification the reaction times were varied from 0 to 3 hours and the chemical changes in molecules of soybean oil were investigated by Nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) spectroscopies. The result suggested that the most suitable condition for ozonolysis reaction was 2 hours considering the decrease in double bond between carbon atoms and the increase in hydroxyl group into molecular structure of MSBO. For the effect of MSBO content on mechanical properties it was evaluated by tensile and impact testing. Differential scanning calorimeter (DSC) and scanning electron microscope (SEM) were used for thermal and morphology analyses. The result showed that elongation at break and impact strength of modified PLA by MSBO increased about 89 and 25 % compared to those of neat PLA respectively. MSBO act as the efficient plasticizer for PLA considering the conversion of fracture behavior from brittle to ductile good dispersions of MSBO droplets in PLA and the decrease of glass transition temperature (Tg) with addition of MSBO. The addition of PF improved the impact strength of modified PLA. Strong interfacial bonding between PLA and PF indicated MSBO being both coupling agent for PLA and natural fiber and plasticizer for PLA. For migration test it was found that contents of released heavy metal and migrated chemical from specimens of PLA and PLA/PF composite were under the criteria according to Notification of the Ministry of Public Health (No. 295) B.E. 2548.

In general the measured resistance with a digital multimeter. Users tend to be measured and then displayed on the screen to the user regardless of the value that is accurate or not. The value displayed on screen digital multimeter may be incorrect. As a result from wires access point measurement and other factor that affect to the value of measurement. Thus the study of factors that affect the measurement to get the accurate and more precise and also can be used in the operations. According to international standard quality system requirements for ISO are clearly on the meter or the measuring device must be calibrated and in the certificate specifies the gain calibration and the uncertainty of measurement. Therefore it is necessary to evaluate the uncertainty of measurement to comply with the standard splash. This thesis presents a study of the effect to the measurement resistance in 0.01 ohm to 100 mega-ohm by direct measurement for 2wire & 4wire Loading effect Using different kinds of conductors Thermal EMF and the stability of the resistor. Include the statistical analysis was used to estimate the uncertainty. From this study can be applied to measure the resistance in a variety of accurately and precisely.

This research aims to study the using cassava pit wastes mixed with cement to particle board walls. The Portland cement type1: fine sand: tap water ratio is equal to 1: 0.5: 0.416 by weight. The ratios of cassava pit wastes to cement are used following: 0.05 0.06 0.07 0.08 0.09 and 0.10 by weight. The cassava pit wastes are crushed by plastic plastics granulators (pass sieve no.4). The casting of particle board walls use the compression machine in room temperature (30 – 35 degree of Celsius) and control 0.75 g/cm3 of density. The TIS 878-2537 standard (cement bonded particle board: high density) is followed to test the properties of particle board wall. Resulting the cassava pit wastes mixed with cement can cast to particle board walls and have good properties especially the thermal insulation property.

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