scholarly journals Isotropy of mechanical properties and environmental stress crack sensitivity in injection‐ and injection‐compression molding of polystyrene with different mold temperature

2021 ◽  
Author(s):  
Benedikt Roth ◽  
Dietmar Drummer
Keyword(s):  
Mechanical Properties ◽  
Environmental Stress ◽  
Mold Temperature ◽  
Compression Molding ◽  
Injection Compression Molding

Study on Optical Properties of Microstructure of Lightguiding Plate for Micro Injection Molding and Micro Injection-Compression Molding

2006 ◽  
Vol 505-507 ◽  
pp. 229-234 ◽  
Author(s):  
Yung Kang Shen ◽  
H.J. Chang ◽  
C.T. Lin
Keyword(s):  
Optical Properties ◽  
Injection Molding ◽  
Digital Camera ◽  
Mold Temperature ◽  
Compression Molding ◽  
Micro Injection Molding ◽  
Melt Temperature ◽  
Packing Pressure ◽  
Injection Compression Molding ◽  
Better Than

The purpose of this paper presents the optical properties of microstructure of lightguiding plate for micro injection molding (MIM) and micro injection-compression molding (MICM). The lightguiding plate is applied on LCD of two inch of digital camera. Its radius of microstructure is from 100μm to 300μm by linearity expansion. The material of lightguiding plate uses the PMMA plastic. This paper uses the luminance distribution to make a comparison between MIM and MICM for the optical properties of lightguiding plate. The important parameters of process for optical properties are the mold temperature, melt temperature and packing pressure in micro injection molding. The important parameters of process for optical properties are the compression distance, mold temperature and compression speed in micro injection-compression molding. The process of micro injection-compression molding is better than micro injection molding for optical properties.

Analysis of the Replication Properties of Lightguiding Plate for Micro Injection Compression Molding

2007 ◽  
Vol 329 ◽  
pp. 643-648 ◽  
Author(s):  
Yung Kang Shen ◽  
H.J. Chang ◽  
L.H. Hung
Keyword(s):  
Process Parameters ◽  
Digital Camera ◽  
Mold Temperature ◽  
Compression Molding ◽  
Single Parameter ◽  
Parameter Method ◽  
Important Process ◽  
Micro Structure ◽  
Melt Temperature ◽  
Injection Compression Molding

This paper presents the application of microstructure replication of lightguiding plate for micro injection compression molding (MICM). The lightguiding plate is applied on LCD of two inch of digital camera. Its radius of micro-structure is from 100μm to 300μm by linearity expansion. The material of lightguiding plate is PMMA. This paper discusses the replication properties for different process parameters by single-parameter method for micro injection compression molding. The important process parameters of replication properties are the mold temperature, compression distance and melt temperature in micro injection compression molding. The mold temperature is the most significant factor of replication properties of microstructure of lightguiding plate for micro injection compression molding.

A Design Methodology to Replicate the Sub-Micron Land-Groove Structure in DVD-RAM Substrates by Injection-Compression Molding

2000 ◽  
Author(s):  
Kibyung Seong ◽  
Su-dong Moon ◽  
Hyun Kim ◽  
Shinill Kang ◽  
Jun-Seok Lee ◽  
...  
Keyword(s):  
Design Methodology ◽  
Mold Temperature ◽  
Compression Molding ◽  
Processing Conditions ◽  
Efficient Design ◽  
Compression Pressure ◽  
Molding Process ◽  
Geometrical Properties ◽  
Groove Structure ◽  
Injection Compression Molding

Abstract Recently, the sub-micron structured substrates of 0.74 μm track pitch and 800 Å groove depth are required for DVD-RAM, and the track pitch is expected to be narrower as the storage density for optical disk is getting higher. For the accurate replication of the land-groove structure in the stamper to the plastic substrates, it is important to control the injection-compression molding process such that the integrity of the replication for the land-groove structure is maximized. However, the determination of the processing conditions has been relied on experience or trial-and-error. In the present study, polycarbonate substrates were fabricated by injection compression molding and the land-groove structure regarded as one of the most important geometrical properties for DVD-RAM substrates was measured. The effects of the mold temperature and the compression pressure on the integrity of the replication were examined experimentally. An efficient design methodology using the response surface method (RSM) and the central composite design (CCD) technique was developed to obtain the optimum processing conditions which maximize the integrity of the replication with a limited number of experiments. The model used in this study was verified using the analysis-of-variance (ANOVA), and it was found to be adequate within the confidence limit.

A Theoretical Analysis on Resin Injection/Compression Molding

2007 ◽  
Vol 334-335 ◽  
pp. 209-212 ◽  
Author(s):  
Akbar Shojaei ◽  
A. Spah
Keyword(s):  
Analytical Solutions ◽  
Mold Filling ◽  
Compression Molding ◽  
Fiber Content ◽  
Flow Front ◽  
Transfer Molding ◽  
Unidirectional Flow ◽  
Resin Injection ◽  
Filling Time ◽  
Injection Compression Molding

In the present investigation, mold filling process of resin injection/compression molding (RI/CM) is compared with resin transfer molding (RTM) for simple mold geometry. To do this, analytical solutions are obtained for RI/CM in unidirectional flow. Based on the analytical solutions, flow front progression and pressure distribution are compared with RTM at different fiber content. The results indicate that the RI/CM reduces the mold filling time significantly, particularly for composite parts with higher fiber content.

scholarly journals Post-Processing Time Dependence of Shrinkage and Mechanical Properties of Injection-Molded Polypropylene

Materials ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 22
Author(s):  
Artur Kościuszko ◽  
Dawid Marciniak ◽  
Dariusz Sykutera
Keyword(s):  
Mechanical Properties ◽  
Impact Strength ◽  
Injection Molding ◽  
Accelerated Aging ◽  
Mold Temperature ◽  
Degree Of Crystallinity ◽  
Injection Mold ◽  
Secondary Crystallization ◽  
Scanning Calorimetry ◽  
Injection Molded

Dimensions of the injection-molded semi-crystalline materials (polymeric products) decrease with the time that elapses from their formation. The post-molding shrinkage is an effect of secondary crystallization; the increase in the degree of polymer crystallinity leads to an increase in stiffness and decrease in impact strength of the polymer material. The aim of this study was to assess the changes in the values of post-molding shrinkage of polypropylene produced by injection molding at two different temperatures of the mold (20 °C and 80 °C), and conditioned for 504 h at 23 °C. Subsequently, the samples were annealed for 24 h at 140 °C in order to conduct their accelerated aging. The results of shrinkage tests were related to the changes of mechanical properties that accompany the secondary crystallization. The degree of crystallinity of the conditioned samples was determined by means of density measurements and differential scanning calorimetry. It was found that the changes in the length of the moldings that took place after removal from the injection mold were accompanied by an increase of 20% in the modulus of elasticity, regardless of the conditions under which the samples were made. The differences in the shrinkage and mechanical properties of the samples resulting from mold temperature, as determined by tensile test, were removed by annealing. However, the samples made at two different injection mold temperature values still significantly differed in impact strength, the values of which were clearly higher for the annealed samples compared to the results determined for the samples immediately after the injection molding.

Effect of Filler Compositions on the Mechanical Properties of Bamboo Filled Polyester Composite

2014 ◽  
Vol 879 ◽  
pp. 90-95 ◽  
Author(s):  
Abdul Rahman Noor Leha ◽  
Nor Amalina Nordin
Keyword(s):  
Mechanical Properties ◽  
Flexural Strength ◽  
Impact Test ◽  
Compression Molding ◽  
Engineering Applications ◽  
Maximum Value ◽  
Polyester Composite ◽  
Bamboo Powder ◽  
Flexural Tests ◽  
The Impact

Biocomposite from bamboo powder was fabricated by compression molding technique. The objective of this study was to investigate the mechanical properties of bamboo compounded with epoxy with different ratio. Tensile and flexural tests were done to characterize its mechanical properties. It was observed that the strength of bamboo-polyester was increased with increasing amount of bamboo powder. The tensile and flexural strength shows the highest value at 25 wt.% bamboo. However, the impact test shows the maximum value at 20 wt.% bamboo powder. These results exhibit the bamboo-polyester can be a good candidate to be used in many engineering applications

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