Determining the Influence of the Processing Temperature by Injection and of the Subsequent Pressure on the Surface�s Hardness and Indentation Modulus of the Products Made of HDPE, PMMA, PC+ABS through Nanoindentation - G-Series Basic Hardness Modulus at a Depth Method

Abstract

The first part of the paper presents the influence of the processing temperature by injection of HDPE, of PMMA, and PC+ABS blend on the indentation hardness and on the indentation modulus, when other factors that can influence the injection remain unchanged. The second part of the paper presents the influence of subsequent pressure by injection of HDPE, PMMA, and PC+ABS blend on the indentation hardness and on the indentation modulus, when the other factors remain unchanged. The HDPE samples were obtained at the following injection temperatures: 180, 190, 200, 210, and 220�C, and at the following subsequent pressures: 800 bar, 900 bar, 1000 bar, 1100 bar, and 1200 bar. The PMMA samples were obtained at the following injection temperatures: 220, 230, 240, 250, and 260�C, and at the following subsequent pressures: 450, 550, 650 , 750, and 850 bar. The PC+ABS samples were obtained at the following injection temperatures: 230, 240, 250, 260, and 270�C, and at the following subsequent pressures: 500 bar, 600 bar, 700, 800, and 900 bar. The G-Series Basic Hardness Modulus at a Depth method was used to obtain the indentation hardness and the indentation modulus. It was observed that by increasing the processing temperature and subsequent pressure, in the case of HDPE, leads to an increase in indentation hardness and in indentation modulus. It was observed that increasing the processing temperature by injection in the case of PMMA, from 220 to 250�C, leads to a slight increase in indentation hardness and in indentation modulus, whereas increasing the subsequent pressure of PMMA, from 450 bar to 850 bar, leads to a slight decrease in indentation hardness and in the indentation modulus. Increasing the processing temperature by injection in the case of PC+ABS, from 230 to 250�C, leads to a slight increase in indentation hardness and in indentation modulus. By further increasing the processing temperature by injection, from 250 to 270�C, leads to a decrease in indentation hardness and in the indentation modulus. Alternatively, increasing the subsequent pressure from 500 bar to 900 bar leads to not only a decrease in indentation hardness but also to a decrease in the indentation modulus.

Study on the Influence of the Grind Percentage Over the Surface Hardness and Modulus of Elasticity of Parts Made of ABS, P6.6 and POM through Nanoindentation

“…The data were obtained by maintaining constant injection parameters specific to each polymer that could alter the properties determined in the study (temperature of injection, mold temperature, injection pressure, holding pressure injection, speed injection cycle time, cooling time in the mold injection, time holding, and pressure time). The hardness and the elastic modulus of the techno polymers investigated in this study appear to be influenced by the grind content [14,26,27].…”

“…The recovery of waste remains a topical issue in the injection molding of thermoplastic polymers. This type of waste appears in different forms: injection network, incomplete parts, plastic parts with burrs, or parts that have other manufacturing defects [10][11][12][13][14][15]. Their reintroduction in the manufacturing process (in the form of grind material) has been practiced for a very long time and leads to significant financial savings.…”

Analysis of supporting indicators for innovation in Romania compared to neighboring EU countries

“…In conclusion, out of the three groups of indicators analyzed, Romania is best placed in terms of Group 3 -Legislative provisions, averaging 31.26% compared to the first rank, followed by group 1 -human resources with an average of 610.24%, and the worst ranking is Group 2support structure / infrastructure, averaging 1205.63% compared with the first ranked countries. The field of innovation and ethical criteria in research should not be neglected [13][14][15][16][17][18][19][20][21][22][23][24][25].…”

Study on the Stability and Compatibility of the Cosmetic Products with Lavandula angustifolia Oil Kept in PPH Polypropylene Homopolymer Plastic Containers

“…In this study, the stability and compatibility of a new cosmetic product containing lavender essential oil was tested and stored in a 100 mL volume PPH plastic homopolymer (Moplen HP648T) plastic container. PPH is the result of the specific polymerization of propane using a Ziegler-Natta catalyst, by injection [11][12][13]. It appears in granular form, stabilized under normal conditions, having a natural color and very good chemical resistance to various chemical agents, basic or acidic.…”