scholarly journals Effects of Injection Molding Parameters on Properties of Insert-Injection Molded Polypropylene Single-Polymer Composites

Polymers ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 23
Author(s):  
Jian Wang ◽  
Qianchao Mao ◽  
Nannan Jiang ◽  
Jinnan Chen

The reinforcement and matrix of a polymer material can be composited into a single polymer composite (SPC), which is light weight, high strength, and has easy recyclability. The insert injection molding process can be used to realize the multiple production of SPC products with a short cycle time and wide processing temperature window. However, injection molding is a very complicated process; the influence of several important parameters should be determined to help in the future tailoring of SPCs to specific applications. The effects of varying barrel temperature, injection pressure, injection speed, and holding time on the properties of the insert-injection molded polypropylene (PP) SPC parts were investigated. It was found that the sample weight and tensile properties of the PP SPCs varied in different rules with the variations of these four parameters. The barrel temperature has a significant effect, followed by the holding time and injection pressure. Suitable parameter values should be determined for enhanced mechanical properties. Based on the tensile strength, a barrel temperature of 260 °C, an injection pressure of 127.6 MPa, an injection speed of 0.18 m/s, and a holding time of 60 s were determined as the optimum processing conditions. The best tensile strength and peel strength were up to 120 MPa and 19.44 N/cm, respectively.

2011 ◽  
Vol 189-193 ◽  
pp. 537-540
Author(s):  
Jia Min Zhang ◽  
Ming Yi Zhu ◽  
Zhao Xun Lian ◽  
Rong Zhu

The use of L27 (35) orthogonal to the battery shell injection molding process is optimized. The main factors of technical parameters were determined mould temperature, melt temperature, the speed of injection, injection pressure, cooling time.On the basis of actual production, to determine the factors values of different process parameters.Combination of scrapped products in key (reduction and a high degree of tolerance deflated) tests were selected in the process parameters within the scope of the assessment. Various factors impact on the product of the total height followed by cooling time, mold temperature, melt temperature, injection pressure, injection speed from strong to weak .The best products technological parameters were determined.Good results were obtained for production.


Author(s):  
Moh. Hartono ◽  
Pratikto ◽  
Purnomo B. Santoso ◽  
Sugiono

This study aims to simultaneously forecast and investigate the optimization process characterization of the design of controlled parameters in the injection process of polypropylene molding including injection pressure combination, clamping force, injection temperature, injection speed, and holding time, and their interaction to produce qualified plastic by minimizing defects. The experimental methods used the central composite design of response surface method with five factors and a variety of levels. This method is more effective because it is an improvement on and a development from previous studies—especially those related to the plastic molding process. Additionally, it can simultaneously predict and optimize the obtaining of the highest quality plastic products as well as minimizing defects. The results are in the form of a combination of control level factors and interactions among the factors that generate the robust output of plastic products with minimum defects. Moreover, the optimum settings of the parameters provides a global solution at an injection temperature of 275°C, injection pressure of 75 bar, injection speed of 98%, clamping force of 88 tons, and a holding time of 8 seconds to generate a response to product probability defects by 0.0062. The benefit is that it can reveal the behavior and characteristics of parameter design and their interactions in the plastic injection molding process to produce qualified plastics and minimize product defects.


Polymers ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 1348 ◽  
Author(s):  
Shih-Chih Nian ◽  
Yung-Chih Fang ◽  
Ming-Shyan Huang

Injection molding is a mature technology that has been used for decades; factors including processed raw materials, molds and machines, and the processing parameters can cause significant changes in product quality. Traditionally, researchers have attempted to improve injection molding quality by controlling screw position, injection and packing pressures, and mold and barrel temperatures. However, even when high precision control is applied, the geometry of the molded part tends to vary between different shots. Therefore, further research is needed to properly understand the factors affecting the melt in each cycle so that more effective control strategies can be implemented. In the past, injection molding was a “black box”, so when based on statistical experimental methods, computer-aided simulations or operator experience, the setting of ideal process parameters was often time consuming and limited. Using advanced sensing technology, the understanding of the injection molding process is transformed into a “grey box” that reveals the physical information about the flow behavior of the molten resin in the cavity. Using the process parameter setting data provided by the machine, this study developed a scientific method for optimal parameter adjustment, analyzing and interpreting the injection speed, injection pressure, cavity pressure, and the profile of the injection screw position. In addition, the main parameters for each phase are determined separately, including injection speed/pressure during the mold filling phase, velocity-to-pressure switching point, packing pressure and time. In this study, the IC tray was taken as an example. The experimental results show that the method can effectively reduce the warpage of the IC-tray from 0.67 mm to 0.20 mm. In addition, the parameters profiles obtained by parameter optimization can be applied for continuous mass production and process monitoring.


Materials ◽  
2005 ◽  
Author(s):  
Adam Kramschuster ◽  
Ryan Cavitt ◽  
Don Ermer ◽  
Chris Shen ◽  
Zhongbao Chen ◽  
...  

This research investigated the effects of processing conditions on the shrinkage and warpage (S&W) behavior of a box-shaped, polypropylene part using conventional, microcellular, and microcellular co-injection molding. Three sets of 26-1 fractional factorial design of experiments (DOE) were employed to perform the experiments and proper statistical theory was used to analyze the data. After the injection molding process reached steady state, molded samples were collected and measured using an optical coordinate measurement machine (OCMM), which had been evaluated using a proper repeatability and reproducibility (R&R) measurement study. By analyzing the statistically significant main and two-factor interaction effects, the results show that the supercritical fluid (SCF) content (nitrogen in this case, in terms of SCF dosage time) and the injection speed affect the S&W of microcellular injection and microcellular co-injection molded parts the most, whereas pack/hold pressure and pack/hold time have the most significant effect on the S&W of conventional injection molded parts. Also, this study quantitatively showed that, within the processing range studied, a reduction in the S&W could be achieved with the microcellular injection molding and micro- cellular co-injection molding processes.


Author(s):  
Aditya Chhabra ◽  
Karanbir Singh ◽  
Himalaya Kanwar

In today’s world, Plastic Injection molding process is one of the most widely used processes for producing plastics products. Engineering plastics is the family capable of withstanding high loading for a period of time at elevated temperatures and in adverse environmental conditions. It exhibits a good balance of high tensile strength, shear strength, toughness to use as replacement of metals in many applications. The aim of this paper is to study the effect of various parameters on the plastic part (used in automobiles). A number of experiments has been conducted by changing the main parameters used in injection molding such as Injection pressure, holding pressure, injection speed etc. All these concerned parameters are responsible for giving the required shape to the part with minimum stresses for better life of the product. Based on above parameters, the weight of the part has been varied which will also help in dimensional stability.


2014 ◽  
Vol 926-930 ◽  
pp. 345-348
Author(s):  
Lai Yu Zhu ◽  
Chun Peng Chu ◽  
Bing Yan Jiang

Reducing volumetric warpage during the injection molding process is a challenging problem in the production of microfluidic chips, as the warpage directly affects the bonding quality of the substrate and the cover sheet. In this study, the injection molding of substrate and the cover sheet, composed of PolymethylMethacrylate(PMMA), was simulated. The effect of different process parameters, holding pressure, holding time, mould temperature and injection speed, were investigated via single factor experiments, observing the warpage of the sheet with Three-Coordinate Measuring Machine. The analysis showed that the warpage was affected by non-uniform shrinkage and residual stress of the melt. Holding pressure and holding time had a greater effect on the warpage than the mould temperature and injection speed did. Therefore, reasonable holding pressure and holding time can effectively reduce the warpage of microfluidic chips in the injection molding process.


2016 ◽  
Vol 23 (2) ◽  
pp. 135-144
Author(s):  
Sinan Dönmez ◽  
Aykut Kentli

AbstractElectrical properties of plastic products can be adjusted by adding a certain amount of carbon nanotubes (CNT) in the injection molding process. However, injection molding parameters should be arranged carefully due to their influence on electrical properties of CNT-reinforced plastic composites. In this study, polycarbonate/CNT nanocomposites, having three different CNT concentrations (1, 3 and 5 wt%), were produced and injection molded by using three different injection temperatures and speeds to investigate their influence on electrical resistivity. It was found that the electrical resistivity was influenced greatly by the injection temperature when 1 wt% amount of CNT was used in the nanocomposite. However, the effect of injection speed was negligible.


2011 ◽  
Vol 341-342 ◽  
pp. 395-399 ◽  
Author(s):  
S. Esmail Mirvar ◽  
Ramin Mohamadi Kaleybar ◽  
Ahmad Afsari

Mechanical properties of plastic play an important role in defining the quality of injection molded products. Many studies have shown that mechanical properties of a product are influenced by the process parameters governing the injection-molding processes .This study employs Taguchi design parameters, to systematically investigate the influence of injection molding processing parameters on the tensile strength of Commercial grade Polyamide (PA-6). The result shows that the holding pressure time has main effect on the tensile strength, followed by cooling time, and holding pressure. Finally, a specimen produced according to the general form of the predictive equation of process parameters and verification test is performed on that. Test results show that the experimental value of tensile strength is very close to the estimated value.


2007 ◽  
Vol 4 (2) ◽  
pp. 1
Author(s):  
Muhammad Hussain Ismail ◽  
Norhamidi Muhamad ◽  
Aidah Jumahat ◽  
Istikamah Subuki ◽  
Mohd Afian Omar

Metal Injection Molding (MIM) is a wellestablished technology for manufacturing a variety of complex and small precision parts. In this paper, fundamental rheological characteristics of MIM feedstock using palm stearin are theoretically analyzed and presented. The feedstock consisted of gas atomized 316L stainless steel powder at three different particle size distributions and the binder system of palm stearin (PS) and polyethylene (PE). The powder loading used was 60vol % for all samples (monosize 16 µm, monosize 45 µm, and bimodal 16 µm + 45 µm) and the binder system of 40vol %(PS/PE = 40/60). The viscosity of MIM feedstock at different temperatures and shear rates was measured and evaluated. Results showed that, the feedstock containing palm stearin exhibited suitable rheological properties by increasing the fluidity of feedstock in MIM process. The rheological results also showed a pseudoplastic flow characteristics, which poses higher value of shear sensitivity (n) and lower value of flow activation energy (E), that are both favourable for injection molding process. The green parts were successfully injected and exhibited adequate strength for handling by optimizing the injection pressure and temperature.


2017 ◽  
Vol 728 ◽  
pp. 258-263
Author(s):  
Badin Pinpathomrat ◽  
Suchalinee Mathurosemontri ◽  
Supaphorn Thumsorn ◽  
Hiroyuki Hamada

Aim of this study focused on insert injection molding process, which is molded the melted polymer around an inserted part placed in the molded cavity of injection molding process. The interfacial adhesive strength between the inserted and an injected polymer parts were investigated by Intron universal test machine in order to investigate the effect of material in inserted and injected part. During tensile testing the acoustic emissions (AE) measurement was applied to evaluate the fracture behavior of insert injection molding. It was found that interfacial adhesive strength of insert injection molded of all specimens increased according with increasing the bonding area of adhesive interface. The fracture mode of the insert injection molded specimens was depended on the length of bonding area of the inserted part. The fracture of mode of the insert-injection molded specimens was confirmed by acoustic emission.


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