Thermal Degradation of the Thermoplastic Elastomers during the Injection Moulding Process

2016 ◽  
Vol 862 ◽  
pp. 148-155 ◽  
Author(s):  
Luboš Bĕhálek ◽  
Jiří Habr ◽  
Martin Seidl ◽  
Petr Lenfeld ◽  
Martin Boruvka
Keyword(s):  
Thermal Degradation ◽  
Injection Moulding ◽  
Physical And Mechanical Properties ◽  
Degradation Process ◽  
Thermoplastic Elastomers ◽  
Chemical Compositions ◽  
Oxidation Induction Time ◽  
Melt Temperature ◽  
Moulding Process ◽  
Injection Moulding Process

The thermal degradation of the thermoplastic elastomers (TPEs) during the injection moulding process – depending on the melt temperature and residence time of the processed material within the barrel of the injection unit, was studied on the basis of oxidation induction time evaluation (isothermal OIT) of the moulded parts (according to ISO 11357-6) and their physical and mechanical properties, according to ISO 1183-1, ISO 37 and ISO 7619-1. TPEs with different chemical compositions intended for automotive, industrial and medical applications were analysed during the study of the thermal degradation process.

Investigating the Effects of Injection Moulding Process Parameters on Multiple Tensile Characteristics of Plastic Spur Gear via Experimental Approach

2013 ◽  
Vol 748 ◽  
pp. 544-548 ◽  
Author(s):  
Nik Mizamzul Mehat ◽  
Shahrul Kamaruddin ◽  
Abdul Rahim Othman
Keyword(s):  
Process Parameters ◽  
Injection Moulding ◽  
Experimental Approach ◽  
Low Cost ◽  
Spur Gear ◽  
Melt Temperature ◽  
Moulding Process ◽  
Packing Pressure ◽  
Injection Moulding Process ◽  
State Of Tension

This paper presents the original development of an experimental approach in studying the multiple tensile characterizations as key quality characteristics for several different plastic gear materials related to various parameters in injection moulding process. In this study, emphases are given on a new low-cost mechanism for the testing of the injection moulded plastic spur gear specimens with various teeth module. The testing fixture are developed and validated to provide uniform state of tension with series of plastic gear specimens produced in accordance with the systematically designed of experiment. The effects of changes in the process parameters including melt temperature, packing pressure, packing time and cooling time at three different levels on the elongation at break and ultimate strength of plastic gear is evaluated and studied through the proposed experimental approach.

Warpage Analysis of Different Number Cooling Channels for Dumbbell Plastic Part in Injection Moulding

2015 ◽  
Vol 761 ◽  
pp. 8-11 ◽  
Author(s):  
Mohd Amran ◽  
Siti Salmah ◽  
Raja Izamshah ◽  
Mohd Shahir ◽  
Mohd Amri ◽  
...  
Keyword(s):  
Injection Moulding ◽  
Simulation Analysis ◽  
Cooling System ◽  
Cooling Channel ◽  
Mould Temperature ◽  
Plastic Part ◽  
Melt Temperature ◽  
Moulding Process ◽  
Cooling Channels ◽  
Injection Moulding Process

Warpage deflection is one of the common pitfalls in plastic injection moulding which is always affected the quality and accuracy of the plastic products. It occurs due to the influences of mould temperature during injection moulding process and it is related to the number of cooling system existed in the mould. Therefore, this paper studies the effect of cooling channels on warpage of dumbbell plastic part having different number of cooling channel using Moldflow software. Warpage analysis was run using four and eight cooling channels. Parameters involved in this study are injection time, packing time, melt temperature and mould temperature. The result of warpage from simulation analysis was projected on the graphic having different colour which is presented the actual value of warpage. It is found from warpage simulation result that the maximum warpage for four cooling channels is 1.283mm and the maximum warpage for eight cooling channels is 1.280mm. It shows that the increasing of the number of cooling channel from four to eight channels in the injection mould reduces the warpage deflection about 0.2%. Thus, the result shows that the number of cooling system in the mould plays an important role on the quality of plastic part during injection moulding process.

A Review of the Effect of Process Parameters on the Performance of Plastic Injection Molding Process to Control the Warpage in Plastics

2015 ◽  
Vol 830-831 ◽  
pp. 116-119 ◽  
Author(s):  
Gurjeet Singh ◽  
Mohan Kumar Pradhan ◽  
Ajay Verma
Keyword(s):  
Process Parameters ◽  
Injection Moulding ◽  
Process Parameter ◽  
Coolant Temperature ◽  
Injection Molding Process ◽  
Melt Temperature ◽  
Influence Of Process Parameters ◽  
Moulding Process ◽  
Injection Moulding Process ◽  
Plastic Injection

Quality control is important aspect of manufacturing process. The quality of product in injection moulding is influenced by injection moulding process parameter. A study of the influence of process parameters on the injection moulding process is presented. Statistically based model approach were studied. In this the process parameter that affect the injection moulding process are like injection time, injection pressure, packing pressure, packing time, cooling time, coolant temperature mold temperature, melt temperature are studied and compared. This paper deals with design of experiment approach to fine out optimal parameter setting. The comparison shows effect of parameters on injection moulding process.Key words: Plastic injection moulding, Orthogonal array, Cycle time

scholarly journals Rheological characterization of polystyrene melts dissolved with supercritical nitrogen fluid during microcellular injection moulding

e-Polymers ◽  
2010 ◽  
Vol 10 (1) ◽  
Author(s):  
Shia-Chung Chen ◽  
Ming-Hsiu Chung ◽  
Yu-Wan Lin ◽  
Ping-Shun Hsu ◽  
Shyh- Shin Hwang ◽  
...  
Keyword(s):  
Injection Moulding ◽  
Rheological Behaviour ◽  
Rheological Characterization ◽  
Melt Temperature ◽  
Moulding Process ◽  
Foaming Process ◽  
Lower Viscosity ◽  
Injection Moulding Process ◽  
Mould Cavity ◽  
Moulding Pressure

AbstractThere are several benefits of using the supercritical fluid microcellular injection moulding process. The part weight, melt temperature, viscosity, moulding pressure, shrink/warpage, and cooling/cycle time are all significantly reduced. The purpose of this study is to investigate the rheological behaviour of PS melt dissolved SCF of nitrogen during Microcellular Injection Moulding process applied with Gas Counter Pressure (GCP) technology. The application of gas into the mould cavity prior to the melt filling provides a counter force against the melt front advancement, restricting the foaming process during the melt filling stage. A slit cavity is designed to measure the pressure drop of polystyrene mixed with 0.4wt% supercritical nitrogen fluid under different mould temperatures (185°C, 195°C, and 205°C), injection speeds (5, 10, and 15 mm/s) as well as counter pressures (0, 150, 300 bars). It was found that melt viscosity is reduced by up to 30% when GCP is increased from 50 to 150 bar as compared to conventional injection moulding. The non-nucleation mixture melt obtained by using a GCP of 300 bar has 32~49% lower viscosity. In addition, the glass transition temperature, Tg, was found to be reduced from 96 °C to 50 °C when the applied GCP is 300 bar.

Micro Injection Moulding Process and Product Characterization

2011 ◽  
Author(s):  
Rossella Surace ◽  
Gianluca Trotta ◽  
Alessandro Bongiorno ◽  
Vincenzo Bellantone ◽  
Claudia Pagano ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Injection Moulding ◽  
Process Conditions ◽  
Scale Production ◽  
Mould Temperature ◽  
Melt Temperature ◽  
Injection Speed ◽  
Moulding Process ◽  
Micro Injection Moulding ◽  
Injection Moulding Process

Due to its high efficiency for the large scale production of polymeric parts, micro injection moulding is one of the key technologies of the new millennium. Although a lot of researches have been conducted to identify the most effective processing conditions for micro injection moulding, the comprehension of the influence of all parameters on the quality, the properties and the reliability of the moulded parts is still an issue. In this context, this study aims to evaluate the effects of the micro injection moulding process conditions on the tensile properties of micro parts, investigating the influence of three main process parameters: the injection speed, the mould temperature and the melt temperature. A full factorial plan has been applied to study the contributions of these parameters and a second study has been performed to understand the synergic interaction between the two temperatures on the tensile strength. Due to its high level of potential crystallinity, a typical semi-crystalline thermoplastic resin was used in the experiments. The results of the analysis showed a great influence of the mould temperature (Tmould) on the ultimate tensile strength and of the melt temperature (Tmelt) on the deformation at the point of breaking; whereas the injection speed was significant on the overall mechanical performance. A new studied factor (Tmelt-Tmould) could affect the resulting molecular structure and consequently the mechanical behaviour, but itself is not sufficient to thoroughly explain the observed behaviour. Moreover, the visual inspection of the deformation mechanism at break shows three distinctive trends demonstrating the great variability of the mechanical properties of micro-injected specimens due to process conditions.

Application of RSM to Optimize Moulding Conditions for Minimizing Shrinkage in Thermoplastic Processing

2016 ◽  
Vol 700 ◽  
pp. 12-21 ◽  
Author(s):  
S.M. Nasir ◽  
K.A. Ismail ◽  
Z. Shayfull
Keyword(s):  
Injection Moulding ◽  
Variable Parameter ◽  
Acrylonitrile Butadiene Styrene ◽  
Cooling Time ◽  
Inlet Temperature ◽  
Melt Temperature ◽  
Mould Material ◽  
Moulding Process ◽  
Packing Pressure ◽  
Injection Moulding Process

This study focuses on the analysis of plastic injection moulding process simulation using Autodesk Moldflow Insight (AMI) software in order to minimize shrinkage by optimizing the process parameters. Two types of gates which is single and dual gates have been analysed. Nessei NEX 1000 injection moulding machine and P20 mould material details are incorporated in this study on top of Acrylonitrile Butadiene Styrene (ABS) as a moulded thermoplastic material. Coolant inlet temperature, melt temperature, packing pressure and cooling time are selected as a variable parameter. Design Expert software is obtained as a medium for analysis and optimisation to minimize the shrinkage. The polynomial models are obtained using Design of Experiment (DOE) integrated with RSM Center Composite Design (CCD) method in this study. The results show that packing pressure is a main factor that contributed to shrinkage followed by coolant inlet temperature, while melt temperature and cooling time has less significant for both single and dual gates. Meanwhile, single gate shows a better result of shrinkage compared to the dual gates.

Application of the Taguchi method for consistent polymer melt production in injection moulding

1998 ◽  
Vol 212 (8) ◽  
pp. 611-620 ◽  
Author(s):  
N Khoshooee ◽  
P D Coates
Keyword(s):  
Injection Moulding ◽  
Polymer Melt ◽  
Acrylonitrile Butadiene Styrene ◽  
Melt Temperature ◽  
Factors Affecting ◽  
Moulding Process ◽  
Control Factors ◽  
Injection Moulding Process ◽  
Moulding Machine ◽  
Noise Factors

The consistency of polymer melt production in the injection-moulding process has been studied using a Taguchi design-of-experiment method for acrylonitrile butadiene styrene (ABS) and high-density polyethylene. Systematic experimentation with injection-moulding machine settings helped to establish both qualitative and quantitative process understanding in attempting to control the melt quality, assessed here by the shot weight variability. Optimum machine settings were determined which gave the lowest variations in the shot weight. In the case of ABS, uncontrollable influences (noise factors; here the injection stroke and moisture content) were incorporated in the study in such a way that the optimum levels recommended by the analysis make the process (i.e. shot weight) insensitive to variations caused by the noise factors. The set melt temperature and screw-back pressure were observed to be the most influential control factors affecting the shot weight variability for both polymers.

Warpage Analysis of Single and Dual Gates Designed for Injection Moulding Using Response Surface Methodology

2015 ◽  
Vol 754-755 ◽  
pp. 775-783 ◽  
Author(s):  
S.M. Nasir ◽  
Khairul Azwan Ismail ◽  
Z. Shayfull ◽  
M.A. Fairuz
Keyword(s):  
Injection Moulding ◽  
Variable Parameter ◽  
Acrylonitrile Butadiene Styrene ◽  
Inlet Temperature ◽  
Melt Temperature ◽  
Mould Material ◽  
Moulding Process ◽  
Packing Pressure ◽  
Injection Moulding Process ◽  
Mould Design

This study focuses on the analysis of plastic injection moulding process simulation using Autodesk Moldflow Insight (AMI) software in order to correlate between process parameters as an input and warpage as an output for single and dual gates mould design. Nessei NEX 1000 injection moulding machine and P20 mould material details are incorporated in this study on top of Acrylonitrile Butadiene Styrene (ABS) as a moulded thermoplastic material. Coolant inlet temperature, material melt temperature, packing pressure and packing time are selected as a variable parameter. Design Expert software is obtained as a medium for analysis and optimization of input variables in order to minimize the warpage. RSM method as well as Analysis of Variance (ANOVA) has been applied in this study. The results of ANOVA show that some interactions between factors are significant towards warpage existence, which is coolant inlet temperature, material melt temperature and packing pressure. Furthermore, the model created using RSM can be used for warpage prediction and improvement due to a minimum value of error. From this study, the dual gate is the best solution which able to improve the warpage up to 80% instead of single.

Effect of Injection Moulding Machine Parameters on the Warpage by Applying Taguchi Method

2014 ◽  
Vol 699 ◽  
pp. 20-25 ◽  
Author(s):  
Mohd Amran ◽  
Siti Salmah ◽  
Abdul Faiz ◽  
Raja Izamshah ◽  
Mohd Hadzley ◽  
...  
Keyword(s):  
Taguchi Method ◽  
Injection Moulding ◽  
Injection Time ◽  
Mould Temperature ◽  
Melt Temperature ◽  
Moulding Process ◽  
Optimum Parameters ◽  
Injection Moulding Process ◽  
The Difference ◽  
Packing Time

The application of Taguchi method to reduce warpage in an injection moulding process is studied. The objective of this paper is to analyze the effect of injection moulding parameters, i.e., injection time, packing time, melt temperature and mould temperature, on the warpage defect in dumbbell plastics part. Optical comparator horizontal type was used to measure the difference of warpage value on each part. L9 orthogonal array with 3 replications was done with 27 totals of specimens. The result collected was optimized using Taguchi method and percentage of contribution was calculated using analysis of variance (ANOVA). According to the analysis, it is found that the significant factors affected warpage are injection time (32.01%), packing time (29.73%), mould temperature (24.39%) and melt temperature (13.87%). The optimum parameters for minimizing the warpage were injection time (1s), packing time (5s), melt temperature (270 °C) and the mould temperature (21 °C). By using Taguchi method and ANOVA analysis, optimum parameters and the percentage of contribution of parameters can be obtained. Thus, it shows that design of experiment method is the good quality tools to get the best quality for production.

Optimum Injection Moulding Processing Condition to Reduce Shrinkage and Warpage for Polypropylene-Nanoclay-Bamboo Fibre with Compatibilizer

2017 ◽  
Vol 889 ◽  
pp. 51-55 ◽  
Author(s):  
M.H. Othman ◽  
Sulaiman Hasan ◽  
Mohd Halim Irwan Ibrahim ◽  
Siti Zubaidah Khamis
Keyword(s):  
Injection Moulding ◽  
Processing Condition ◽  
Screw Speed ◽  
Melt Temperature ◽  
Moulding Process ◽  
Bamboo Fibre ◽  
Packing Pressure ◽  
Injection Moulding Process ◽  
Filling Time

The purpose of this research is to optimise the processing condition of injection moulding towards samples made from polypropylene-nanoclay-bamboo fibre with compatibilizer. The defects that have been controlled upon the optimisation were shrinkage and warpage. The selection of injection moulding processing condition was packing pressure, melt temperature, screw speed and filling time. The research started by drying the bamboo fibres at 120°C. Then, the 1 wt. % fibres were mixed with 79 wt. % of polypropylene, 15 wt. % of compatibilizer and 5 wt. % of nanoclay. The mixing process was performed by using Brabender Plastograph machine. After that, pallets were produced by using Plastic Granulator machine for injection moulding process. The optimisation process was accomplished by adopting the Taguchi method. According to the results, the value of warpage defect between compounding for 1 wt. % fibre and without fibre content was not significant. However the optimum setting of 170°C melt temperature, 35% packing pressure, 30% screw speed and 2 seconds filling time can significantly reduce shrinkage. In conclusion, the optimum processing condition of polypropylene-nanoclay, fibre bamboo had been achieved, and the existence of fibre obviously giving a promising manufacturing opportunity to improve the quality of the injected moulding products.

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