94 ENVIROMENTAL PROPERTIES LAB SHEET : WATER ABSORPTION TEST At the end of this task, the student should be able to: Identify the standard and equipment used in plastic material testing. Conduct various types of plastic materials testing independently using Standard Operation Procedure (SOP). Interpret the data and result findings in plastic materials testing. Theory Water absorption is used to determine the amount of water absorbed under specified conditions. Various polymeric materials are susceptible to water absorption during its life exposure. This may cause dimensional instability with property degradation and ultimately lead to failure. This test was designed to evaluate materials by exposing specimens to water for different time & temperature profiles. Testing is conducted on specimens that are submersed in water and a before & after weight change is documented. Depending on the application of the product, certain levels of moisture are accepted. Factors affecting water absorption include: type of plastic, additives used, temperature and length of exposure. The data sheds light on the performance of the materials in water or humid environments. According to ASTM D570 for water absorption test. The percentage of water absorption, (Mt), was calculated according to the following formula: Mt = Wn – Wd / Wd x 100 Where; Wd= Original dry weight Wn= Weight after immersed
95 Apparatus/Equipments Balance – An analytical balance capable reading 0.0001g. Oven, capable maintaining uniform temperatures of 50 oC +/- 3 oC and 105 oC to 110oC. The test specimen thickness are +/-0.18mm for hot molded and +/- 0.30mm for cold molded. Distilled Water and plastics cup. Safety Precautions Always keep the floor clean. Always keep the floor clean. Always use the correct tool for the job. Keep tools in the boxes or racks when not in use. Operate the machine with wearing personal protective equipment such as glove and mask. Never try to bypass the guard safety interlock. Make sure that all safety devices are working properly. Procedure i. Samples of sheet plastics were prepared with approximate dimensions of 25mm x 20mm x 1mm. ii. The samples were dried at 80˚C for 24 hours. iii. Immersed in distilled water at room temperature until a constant weight was reached. iv. The specimens were periodically taken out of the water, wiped with tissue paper to remove surface water and weighed. v. At least three specimens for each sample were used. A Mettler balance type was used, with 0.0001g accuracy. vi. Write results in the table, and collect the data until a month or 31 days.
96 Result/Data Complete this below table: Time(Days) Water Absorption (%) Sample 1 Sample 2 Sample 3 Sample 4 Sample 5 1 2 3 4 5 6 7 9 11 13 15 17 19 21 23 25 27 29 31 Discussions Plot a graph Percent(%) Water Absorption Versus Days. Conclusion and Recommendation Your conclusion should be related to your workshop objective and suggest your recommendation to improve the quality of product. References State your reference either refer to books, articles, or journals.
97 OPTICAL AND ELECTRICAL PROPERTIES LAB SHEET : HAZE GARD PLUS TESTING At the end of this task, the student should be able to: Identify the standard and equipments used in plastic material testing. Conduct various types of plastic materials testing independently using Standard Operation Procedure (SOP). Interpret the data and result findings in plastic materials testing. Theory Haze gard plus is a stationary instruments designed to measure the appearance of glass and of films, packaging and parts made of plastic and other transparent materials. The specimen surface is illuminated perpendicularly and the transmitted light is measured photoelectrically, using an integrating sphere (0% diffuse geometry).The spectral sensitivity conforms to CIE standard spectral value function y, under standard light C resp A. Three parameters: Total transmittance Haze Clarify Haze gard plus conforms to the standards ASTM D-1003 and ASTM D-1044. Apparatus/Equipments BYK Gardner Haze – gard plus Sample plastics
98 Safety Precautions Always keep the floor clean. Always keep the floor clean. Always use the correct tool for the job. Keep tools in the boxes or racks when not in use. Operate the machine with wearing personal protective equipment such as glove and mask. Never try to bypass the guard safety interlock. Make sure that all safety devices are working properly. Procedure i. Switch on the haze gard plus machine. ii. Setting display on ‘statistic mode’. iii. Put the specimen on the specimen holder. iv. Move specimen to ‘haze port’ for experiment 1 & 2 v. For experiment 3 and 4, range positions of materials was variable and size distance from the port CLARIFY was measure.
99 Result/Data Experiment 1 Write the haze value of the different specimens (A, B, C, D, PP) Select at random five (5) different points on each specimen Complete this below table. EXPERIMENT 1 Reading A B C D PP 1 2 3 4 5 Average Experiment 2 Study the effect of thickness on the Transmittance Select at random five (5) different points on each specimen. Variable thickness up to 4 pieces. Complete this below table EXPERIMENT 2 Reading 1 piece 2 pieces 3 pieces 4 pieces 1 2 3 4 5 Average
100 Experiment 3 Obtain the haze and transmittance values for range of specimens with different port. Select five(5) distances value of different specimen. Complete this below table. Reading EXPERIMENT 3 Distance 1 Distance 2 Distance 3 Distance 4 H T H T H T H T 1 2 3 4 5 Average Plot the below diagram thickness distances distances T H T
101 Discussions i. Discuss how material properties affect the haze and transmittance. ii. List the effect of specimen thickness and the distance from the port to the value of transparency iii. What is the importance of statistical quality control? Conclusion and Recommendation Your conclusion should be related to your workshop objective and suggest your recommendation to improve the quality of product. References State your reference either refer to books, articles, or journals.
102 LAB SHEET : TRI GLOSS At the end of this task, the student should be able to: Identify the standard and equipments used in plastic material testing. Conduct various types of plastic materials testing independently using Standard Operation Procedure (SOP). Interpret the data and result findings in plastic materials testing. Theory The light emitted onto the surface of a test at the prescribed angle and turns the light used photoelectrically. Reflectometer measured at certain angle geometry to measure the luminosity to scale the following materials
103 Apparatus/Equipments The Micro Tri Gloss Mobile measurement device suitable for measuring the surface gloss paints, plastics, ceramics and other materials from the same type. Samples are from the same material that has changed the surface. Safety Precautions Always keep the floor clean. Always keep the floor clean. Always use the correct tool for the job. Keep tools in the boxes or racks when not in use. Operate the machine with wearing personal protective equipment such as glove and mask. Never try to bypass the guard safety interlock. Make sure that all safety devices are working properly. Procedure TEST METHOD i. Switch on the tools and make sure it has the calibrate. ii. Select the geometric angle by pressing the mode button until there is change in the display geometry. Select the desired angle and press the operate button. iii. Select the measurement mode by pressing the mode button again. iv. Put the equipment on the surface of the material to be tested. Result/Data Obtain an average value of surface brightness by taking several readings in the following table: SAMPLE % GLOSS 1 2 3 4 5 AVERAGE
104 Discussions Get the following table and discuss the result. SAMPLE % GLOSS 1 2 3 4 5 Conclusion and Recommendation i. What is the value of observations of a sample of different luminosity? ii. For each sample is found to be the same luminosity? Why? References State your reference either refer to books, articles, or journals.
105 REFERENCES i. Vishu Shah (2007) Handbook of Plastics Testing and Failure Analysis. Technology & Engineering. ii. James S. Peraro (2000 ) Limitations of Test Methods for Plastics, Issue 1369, American Society for Testing and Materials - Technology & Engineering. iii. B. Mathur, I. S. Bhardwaj, A. B. Mathur (2003) Testing and Evaluation of Plastics - Plastics – v. Sandra L. Kessler (1987) -Instrumented Impact Testing of Plastics and Composite Materials ..., Issue 936- Technology & Engineering. vi. en.wikipedia.org/wiki/Mechanical_Plastics_Corp vii. www.apmtesting.com/testing-services/materials-tested/plastic-testing.php viii. www.astm.org/Standards/plastics-standards.html ix. https://www.benmeadows.com/store/assets/.../NalgenePlasticwareChart.pd. x. www.jsm.gov.my/standard malaysia
106