Studying single-pass degradation of a high-density polyethylene in an injection molding process

Abstract In this work, the effect of the initial and secondary temperature differences on the solidification behaviors of high-density polyethylene (HDPE) during the thin-walled injection molding (TWIM) was intensively investigated. Simulated temperature profiles using the enthalpy transformation methodology were compared with an in situ temperature measurement, and reasonable agreement was achieved between calculations and measurements. Two-dimensional wide-angle X-ray diffraction characterization shows that the formation of oriented crystal structures was considerably affected by the thermal gradient within the injection-molded article. The present study can be practically significant to the optimization of the cooling parameters during the TWIM of crystalline polymers as well as to the further study on the relationship among “processing-structure-property” of polymeric materials.

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Solidification behavior of high-density polyethylene during injection molding process: Enthalpy transformation method

Journal of Applied Polymer Science ◽

10.1002/app.38376 ◽

2012 ◽

pp. n/a-n/a

Author(s):

Bin Yang ◽

Ji-Bin Miao ◽

Kai Min ◽

Ru Xia ◽

Jia-Sheng Qian ◽

...

Keyword(s):

Injection Molding ◽

High Density Polyethylene ◽

Transformation Method ◽

High Density ◽

Injection Molding Process ◽

Solidification Behavior ◽

Molding Process

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Rice Husk/High Density Polyethylene Bio-Composite: Effect of Rice Husk Filler Size and Composition on Injection Molding Processability with Respect to Impact Property

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.83-86.367 ◽

2009 ◽

Vol 83-86 ◽

pp. 367-374 ◽

Cited By ~ 7

Author(s):

Wan Aizan Wan Abd. Rahman ◽

N.M. Isa ◽

A.R. Rahmat ◽

N. Adenan ◽

R.R. Ali

Keyword(s):

Impact Strength ◽

Injection Molding ◽

Rice Husk ◽

High Density Polyethylene ◽

Injection Molding Process ◽

Melt Flow ◽

Molding Process ◽

Melt Flow Rate ◽

Filler Size ◽

The Impact

The compounding of rice husk and high density polyethylene (HDPE) was undertaken on a Sino PSM 30 co-rotating twin screw extruder. Four sizes of rice husk were studied at various compositions. The size ranged from 500 μm and below (coded A, B, C and D) while the content of rice husk in the composite varies from 30, 40 and 50 percent of weight. A fixed amount of Ultra-Plast TP10 as a compatibilizer and Ultra-Plast TP 01 as lubricant, were added into the bio-composite compound. The injection molding process ability of the bio-composite was studied through flow behavior on melt flow indexer and analyzed on JSW N100 B11 Injection Molding. Size A which has the largest particle is the most appropriate size as the bio-composite filler based on thermal stability test. The melt flow rate of rice husk/HDPE (RHPE) decreases with the increased in rice husk compositions and apparent viscosity also increases with composition for all filler size. Melt flow rate above 4g/10 min was found to be the lower limit for injection molding process. The smaller the filler size, the lower is the impact strength and the increased in the filler composition lowers the impact strength. A bio-composite at 30 weight percent rice husk size A (RH30PEA) was found to have optimum rheological properties with respect to impact strength.

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Experimental study of penetration interfaces in the overflow fluid-assisted co-injection molding process

Journal of Polymer Engineering ◽

10.1515/polyeng-2014-0369 ◽

2016 ◽

Vol 36 (2) ◽

pp. 139-148 ◽

Cited By ~ 6

Author(s):

Tangqing Kuang ◽

Chuncong Yu ◽

Baiping Xu ◽

Lih-Sheng Turng

Keyword(s):

Experimental Study ◽

Injection Molding ◽

Cross Section ◽

High Density Polyethylene ◽

Flow Direction ◽

Injection Molding Process ◽

Molding Process ◽

The Difference ◽

The Stability ◽

Plastic Products

Abstract The fluid-assisted co-injection molding (FACIM) process can be used to produce hollow plastic products with outer and inner layers. It can be divided into two categories: water-assisted co-injection molding (WACIM) and gas-assisted co-injection molding (GACIM). An experimental study of penetration interfaces in overflow FACIM was carried out based on a lab-developed FACIM system. High-density polyethylene and polypropylene were used as the outer layer and inner layer plastics, respectively, in the experiments and the injection sequence was reversible. Six cross-section cavities were investigated in the experiments. The penetration behaviors of water and gas in different sequences and cavities were compared and analyzed. The penetration interfaces were characterized by the residual wall thickness (RWT). The experimental results showed that the RWT of the inner layer in WACIM fluctuated along the flow direction, while that in GACIM was more even. The difference of viscosity between the outer and inner layer melts affected the stability of the interface between them. The penetration sections of the inner layer and the gas were closer to the cavity sections in GACIM, while the penetration sections of the inner layer and the water were closer to the circular forms in WACIM.

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High Density Polyethylene (HDPE) composite mixed with Azadirachta excelsa (Sentang) tree waste flour: Mechanical and physical properties

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/951/1/012045 ◽

2022 ◽

Vol 951 (1) ◽

pp. 012045

Author(s):

A M Zakaria ◽

M A Jamaludin ◽

M N Zakaria ◽

R Hassan ◽

S A Bahari

Keyword(s):

Physical Properties ◽

High Density Polyethylene ◽

Flexural Modulus ◽

Filler Loading ◽

High Density ◽

Injection Molding Process ◽

Molding Process ◽

Significant Difference ◽

Mechanical And Physical Properties ◽

Composite Samples

Abstract This article presents the application of plantation waste materials (leaves, branches and trunks) of Azadirachta excelsa (Sentang) tree in order to evaluate and compare their suitability as reinforcement and filler for high density polyethylene (HDPE) thermoplastics. The aim of the study was to investigate the effect of different types of Azadirachta excelsa (Sentang) trunks flour, branches flour and leaves flour fillers on the mechanical and physical properties of HDPE composite. The composite samples were produced using 25%, 35% and 45% by weight of flour filler loading and 2% coupling agent (maleic anhydride) using a twin-screw extruder, followed by injection molding process. The flexural modulus and tensile strength of the composite filled with trunk flour were not significantly different with the composite-filled branch flour. However, there is a significant difference between composite-filled leaf flour when compared to both composite-filled trunk flour and composite-filled branch flours. Overall, composite samples with trunk flour show better mechanical properties, while composite samples with lower filler loadings of 25% exhibit better dimensional stability compared to the other such as 35% and 45% filler loadings. The study also indicated that composite filled with leaf, branch and trunk flours had better mechanical strength than virgin HDPE.

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