Injection-moulding of nitrogen-foamed bio-based microcellular poly(butylene succinate): Processing conditions/foam structure/flexural properties relationship

This paper aims to identify the main processing parameters that optimize as well the microcellular structure (cell size, cell density) of nitrogen (N2) foamed injection-moulded poly(butylene succinate) (PBS) as the resultant flexural properties of the part. The part beam geometry was designed so as to reproduce some geometrical shapes (e.g. thickness change, ribs, bosses or holes) occurring on most of industrial parts. A Taguchi L9 design of experiments (DOE) has been first used to quantify the effects of processing conditions on microcellular structure and mechanical performances. Among the processing parameters, the melt temperature, gas content, injection volumetric flow rate and back pressure were chosen for the DOE due to their level of influence on gas dissolution and nucleation phases. An analysis of variance (ANOVA) showed that the microcellular structure depended mainly on nitrogen content and, to a lesser extent, on back pressure representation of gas pressure saturation in the PBS/N2 system during the feeding stage. The resultant specific flexural properties were controlled by the skin/core ratio as well as the finesse of foam structure (cell sizes, cell density) but a 15% loss in specific performances was noted compared with the unfoamed part. The microcellular structure/mechanical performances could be thus established from the microstructure analysis. In a second step, the foamed microcellular structure has been improved by introduction of micro-talc in the PBS acting as cell nucleating agent (heterogeneous nucleation). A significant increase in cell density and cell reduction (40%) were observed.

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Binary Self-Assembly of Nanocolloidal Arrays using Concurrent and Sequential Spin Coating Techniques

Materials ◽

10.3390/ma14020274 ◽

2021 ◽

Vol 14 (2) ◽

pp. 274

Author(s):

Shih-Jyun Shen ◽

Demei Lee ◽

Yu-Chen Wu ◽

Shih-Jung Liu

Keyword(s):

Silicon Substrate ◽

Self Assembly ◽

Spin Coating ◽

Processing Parameters ◽

The Self ◽

Silicon Substrates ◽

Processing Conditions ◽

Polystyrene Spheres ◽

Optimal Processing ◽

Spin Coater

This paper reports the binary colloid assembly of nanospheres using spin coating techniques. Polystyrene spheres with sizes of 900 and 100 nm were assembled on top of silicon substrates utilizing a spin coater. Two different spin coating processes, namely concurrent and sequential coatings, were employed. For the concurrent spin coating, 900 and 100 nm colloidal nanospheres of latex were first mixed and then simultaneously spin coated onto the silicon substrate. On the other hand, the sequential coating process first created a monolayer of a 900 nm nanosphere array on the silicon substrate, followed by the spin coating of another layer of a 100 nm colloidal array on top of the 900 nm array. The influence of the processing parameters, including the type of surfactant, spin speed, and spin time, on the self-assembly of the binary colloidal array were explored. The empirical outcomes show that by employing the optimal processing conditions, binary colloidal arrays can be achieved by both the concurrent and sequential spin coating processes.

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Effects of Injection Molding Screw Tips on Polymer Mixing

Periodica Polytechnica Mechanical Engineering ◽

10.3311/ppme.12183 ◽

2018 ◽

Vol 62 (3) ◽

pp. 241-246 ◽

Cited By ~ 2

Author(s):

Dániel Török ◽

József Gábor Kovács

Keyword(s):

Injection Molding ◽

Processing Parameters ◽

Raw Material ◽

Molding Machine ◽

Surface Color ◽

Melt Temperature ◽

Injection Molding Machine ◽

Aesthetic Appearance ◽

Molded Parts ◽

Injection Molded

In all fields of industry it is important to produce parts with good quality. Injection molded parts usually have to meet strict requirements technically and aesthetically. The aim of the measurements presented in our paper is to investigate the aesthetic appearance, such as surface color homogeneity, of injection molded parts. It depends on several factors, the raw material, the colorants, the injection molding machine and the processing parameters. In this project we investigated the effects of the injection molding machine on surface color homogeneity. We focused on injection molding screw tips and investigated five screw tips with different geometries. We produced flat specimens colored with a masterbatch and investigated color homogeneity. To evaluate the color homogeneity of the specimens, we used digital image analysis software developed by us. After that we measured the plastication rate and the melt temperature of the polymer melt because mixing depends on these factors. Our results showed that the screw tips (dynamic mixers) can improve surface color homogeneity but they cause an increase in melt temperature and a decrease in the plastication rate.

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Correlation between Process Parameters with Flexural Properties of Hybrid Glass/Jute Fibre Reinforced Epoxy Composite Fabricated via Vacuum Infusion Technique

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.761.531 ◽

2015 ◽

Vol 761 ◽

pp. 531-535

Author(s):

Noraiham Mohamad ◽

Mohd Fadli Hassan ◽

Siang Yee Chang ◽

Qumrul Ahsan ◽

Yuhazri Yaakob ◽

...

Keyword(s):

Epoxy Composite ◽

Processing Parameters ◽

Bending Test ◽

Flexural Properties ◽

Jute Fibre ◽

Soaking Time ◽

Three Point Bending ◽

Vacuum Infusion ◽

Supply Pressure ◽

Infusion Technique

Flexural properties of hybrid glass/jute fibre reinforced epoxy composites were optimised by response surface methodology. The processing parameters of vacuum infusion technique such as supply pressure, soaking time and use of flow media were investigated. The flexural properties of the resulting composites were evaluated using three-point bending test in accordance with the ASTM D790-03 standard. The flexural strength of ~195 MPa and elastic modulus of ~13412 MPa were achieved at optimum parameter of 100 kPa pressure, 120 minutes soaking time with the utilization of flow media during vacuum infusion process.

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Warpage and Shrinkage Analysis and Optimization of Rapid Tooling Molded thin Wall Component Using Modified Particle Swarm Algorithm

Journal of Advanced Manufacturing Systems ◽

10.1142/s0219686719500045 ◽

2019 ◽

Vol 18 (01) ◽

pp. 85-102 ◽

Cited By ~ 2

Author(s):

Sagar Kumar ◽

Amit Kumar Singh

Keyword(s):

Injection Molding ◽

Process Parameters ◽

Simulation Analysis ◽

Statistical Significance ◽

Particle Swarm ◽

Processing Parameters ◽

Particle Swarm Algorithm ◽

Thin Wall ◽

Polybutylene Terephthalate ◽

Melt Temperature

This paper presents a systematic methodology to determine optimal injection molding conditions for minimum warpage and shrinkage in a thin wall relay part using modified particle swarm optimization algorithm (MPSO). Polybutylene terephthalate (PBT) and polyethylene terephthalate (PET) were injected in a thin wall relay component for different processing parameters: melt temperature, packing pressure and packing time. Further, Taguchi’s L9 (3[Formula: see text] orthogonal array is used for conducting simulation analysis to consider the interaction effects of the above parameters. A predictive mathematical model for shrinkage and warpage is developed in terms of the above process parameters using regression analysis. ANOVA analysis is performed to establish statistical significance within the injection molding parameters. The analytical model is further optimized using a newly developed MPSO algorithm and the process parameters values are predicted for minimizing shrinkage and warpage. The predicted values of shrinkage and warpage using MPSO algorithm are improved by approximately 30% as compared to the initial simulation values and comparable to previous literature results.

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The effect of foaming agent on mechanical and physical properties of Polypropylene

Materials Science Advanced Composite Materials ◽

10.18063/msacm.v2i1.693 ◽

2018 ◽

Vol 2 (1) ◽

Cited By ~ 1

Author(s):

SEDEF CAKIR 1 ◽

MUHAMMED AYCICEK 1 ◽

EDIZ ALTUN 2 ◽

Akin Akinci 1

Keyword(s):

Mechanical Properties ◽

Cell Density ◽

Cell Morphology ◽

Injection Pressure ◽

Skin Layer ◽

Polymer Materials ◽

Cell Diameter ◽

Melt Temperature ◽

Foaming Agent ◽

Foaming Agents

In this study, Polypropylene (PP) foam materials were used with injection parameters such as melting, molding and injection temperatures. To produce foam materials, chemical foaming agents were used, and added to polymer materials as 1wt.%, 1.5wt.%, 2wt.%, 2.5wt.%, 3wt.%. The mechanical properties of foam samples were determined based on the parameters. Cell morphology characterization such as cell diameter, cell count, skin layer thickness and cell density, and mechanical properties such as tensile and impact strength of polymer foams were examined.Generally, the closed-cell foam structure was obtained. The most important parameters affecting the cell morphology have been injection pressure, melt temperature and amount of foaming agent. With increasing the amount of foaming agent, cell density increased, foam density and mechanical properties decreased.

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Microscale Thermoplastic Forming of Bulk Metallic Glasses: Numerical Simulations and Experiments

Volume 13: Nano-Manufacturing Technology; and Micro and Nano Systems, Parts A and B ◽

10.1115/imece2008-67340 ◽

2008 ◽

Author(s):

David L. Henann ◽

Lallit Anand

Keyword(s):

Numerical Simulation ◽

Metallic Glasses ◽

Bulk Metallic Glasses ◽

Processing Parameters ◽

Hot Embossing ◽

Simulation Tool ◽

Processing Conditions ◽

Trial And Error ◽

Physical Experiments ◽

Thermoplastic Forming

An extremely promising microscale processing method for bulk metallic glasses called thermoplastic forming has emerged in recent years. However, most of the recent experimental thermoplastic forming studies have been conducted by trial-and-error. In this paper, the large-deformation constitutive theory of Henann and Anand [1] is used as a numerical simulation tool for the design of micro-hot-embossing processes. This numerical simulation capability is used to determine appropriate processing parameters in order to carry out several successful micron-scale hot-embossing operation on the metallic glass Zr41.2Ti13.8Cu12.5Ni10Be22.5 (Vitreloy-1). By carrying out the corresponding physical experiments, it is demonstrated that microscale features in Vitreloy-1 may be accurately replicated under the processing conditions determined by use of the numerical simulation capability.

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Poly(Butylene Succinate) Composites Reinforced with Short Sisal Fibres

Polymers and Polymer Composites ◽

10.1177/096739110100900504 ◽

2001 ◽

Vol 9 (5) ◽

pp. 333-338 ◽

Cited By ~ 3

Author(s):

Mitsuhiro Shibata ◽

Retsu Makino ◽

Ryutoku Yosomiya ◽

Hiroyuku Takeishi

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Fibre Length ◽

Mechanical Analysis ◽

Fibre Content ◽

Flexural Properties ◽

Melt Mixing ◽

Butylene Succinate ◽

Sisal Fibre ◽

The Matrix

Poly(butylene succinate) composites reinforced with short sisal fibre were prepared by melt mixing and subsequent injection moulding. The influence of fibre length, fibre content and the surface treatment of the natural fibres on the mechanical properties of the composites were evaluated. Regarding fibre length, the tensile and flexural properties of the composites had maxima at a fibre length of about 5 mm. The flexural and tensile moduli of the composites increased with increasing fibre content. Although the tensile strength hardly changed, the flexural strength increased up to a fibre content of 10 wt%. The dynamic mechanical analysis of the composites showed that the storage moduli at above ca.-16°C (corresponding to the glass transition temperature of the matrix) increased with increasing fibre content.

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Polylactide (PLA) and Its Blends with Poly(butylene succinate) (PBS): A Brief Review

Polymers ◽

10.3390/polym11071193 ◽

2019 ◽

Vol 11 (7) ◽

pp. 1193 ◽

Cited By ~ 37

Author(s):

Shen Su ◽

Rodion Kopitzky ◽

Sengül Tolga ◽

Stephan Kabasci

Keyword(s):

Material Properties ◽

Chemical Structure ◽

Building Blocks ◽

Processing Parameters ◽

International Standards ◽

Butylene Succinate ◽

Reactive Compatibilization ◽

Application Potential ◽

Specific Material

Polylactide (PLA), poly(butylene succinate) (PBS) and blends thereof have been researched in the last two decades due to their commercial availability and the upcoming requirements for using bio-based chemical building blocks. Blends consisting of PLA and PBS offer specific material properties. However, their thermodynamically favored biphasic composition often restricts their applications. Many approaches have been taken to achieve better compatibility for tailored and improved material properties. This review focuses on the modification of PLA/PBS blends in the timeframe from 2007 to early 2019. Firstly, neat polymers of PLA and PBS are introduced in respect of their origin, their chemical structure, thermal and mechanical properties. Secondly, recent studies for improving blend properties are reviewed mainly under the focus of the toughness modification using methods including simple blending, plasticization, reactive compatibilization, and copolymerization. Thirdly, we follow up by reviewing the effect of PBS addition, stereocomplexation, nucleation, and processing parameters on the crystallization of PLA. Next, the biodegradation and disintegration of PLA/PBS blends are summarized regarding the European and International Standards, influencing factors, and degradation mechanisms. Furthermore, the recycling and application potential of the blends are outlined.

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Effects of Ball Milling Processing Conditions and Alloy Components on the Synthesis of Cu-Nb and Cu-Mo Alloys

Materials ◽

10.3390/ma12081224 ◽

2019 ◽

Vol 12 (8) ◽

pp. 1224 ◽

Cited By ~ 1

Author(s):

Xuekun Shang ◽

Xitao Wang ◽

Silian Chen

Keyword(s):

Size Distribution ◽

Ball Milling ◽

Oxidation Process ◽

Processing Parameters ◽

Processing Conditions ◽

Cold Welding ◽

Immiscible Alloys ◽

Ball Size ◽

Milling Method

The effects of processing parameters in ball milling and the different behaviors of Cu-Nb and Cu-Mo alloys during milling were investigated. High powder yields can be obtained by changing the BPR value and ball size distribution and no clear dependence of BPR value on powder yield can be found from the experiment results. The addition of oxygen can largely reduce the effect of excessive cold welding during ball milling. A “two-step” ball milling method was introduced to evaluate the different evolution processes and morphologies in different alloys. With 8 h pre-milling, this method considerably benefits the oxidation process of Mo and shows its promising potential in the synthesis of immiscible alloys. Based on the experiment results and analysis, we suggest that the different behaviors of Cu-Nb and Cu-Mo alloys are related to the shear modules and different tendencies to be oxidized.

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