จำนวน Repository ( 15 )
สมบัติการบวมตัวของพอลิเอทิลีนความหนาแน่นสูงหลอมเหลวในหัวขึ้นรูปแบบวงแหวน
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.
การใช้เศษพลาสติกโพลิเอทธิลีนเทเรฟทาเลตเป็นวัสดุผสมสำหรับผลิตไม้เทียมขยะกล่องนมที่มีความแข็งแรงสูง
The objectives of this research are to study the production to find the proper ratio to test the properties to suggest the implementation and to transfer the technology of high strength milk carton waste artificial wood mixed with poly ethylene terephthalate (PET) plastic waste. The ratios of this artificial wood included milk carton waste: PET plastic waste equal to 80:20 75:25 70:30 65:35 and 60:40 by weight. The milk carton and PET plastic wastes were grinded though sieve no.4. The artificial woods were casted by hot compression with 180 degree of Celsius for 5 minutes. The samples tested follow the TIS.966-2547 standard. From the results the 60:40 of ratio was the proper ratio which can pass the standard. The increasing of PET waste effected to decrease the density moisture and swelling of properties. In case of bending strength elastic modulus and tensile strength perpendicular to surface the increasing of PET effected to decrease their properties. The developed artificial wood mixed with milk cotton waste and PET plastic waste has the possibility to implement in decoration and construction both interior and exterior wall building. These results can register the petty patent and write the research paper which to transfer the technology.
Molecular weight polyethylene composites for high wear resistance under temperature changes and lubricant to apply for use in industrial machinery parts
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
Study the shrinkage percentage of plastic polyethylene terephthalate (PET) used with make blow mold
The shrinkage depended on the product shape and the type of plastic used in blow This research aims to study the shrinkage percentage of plastic polyethylene terephthalate grade : N1 used with the make blow mold in 2 stages. The testing results were as follow. vertical shrinkage percentage ( Z axis ) was 0.787 percentage and horizontal shrinkage Percentage ( XY axis ) was 2.13 percentage
The Effect of chain extender on rheological properties of recycledpoly (ethyleneterephthalate)
The effect of chain extender on the improvement of molecular structure and rheological properties in shear and elongation of recycled poly (ethylene terephthalate) was studied. The results suggested that addition of chain extender increased the molecular weight and broader molecular weight distribution of recycled poly (ethylene terephthalate). A gel fraction of cross-linked material was formed and the amount of gel content was dependent on the amount of chain extender used. Moreover it was found that the addition of chain extender increased the shear and elongational viscosities of recycled poly(ethylene terephthalate). The increases of viscosities were explained that the extension of poly (ethylene terephthalate) chains caused a reduction in chain mobility. As for the tensile properties at the molten and solidified state it was seen that the increase of tensile properties resulting from chain extender rose up to 0.6 wt% before it reduced at the chain extender loading of 0.9 wt%.