Evaluation of Process Wear of Selected Tool Steels for Injection Molds

The aim of this contribution is to test the suitability of selected types of tool steels used for manufacturing of injection molds. Experiments were realized by the simulation of adhesive wear using laboratory equipment Amsler, which allows the testing of grinding pairs. Evaluated grinding pairs consisted of tool steel and two types of roundels. Tested polymeric materials were based on pure PA6 and PBT filled with short glass fibers, prepared by mixing process in twin screw extruder. The wear of five types of tool steels were evaluated by weight decrease before and after the experiment, while changing the friction coefficient of grinding pairs, material of grinding pairs and sensing the roughness of steel before and after wear.

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Behaviour of PLA/POSS nanocomposites: Effects of filler content, functional group and copolymer compatibilization

Polymers and Polymer Composites ◽

10.1177/09673911211008020 ◽

2021 ◽

pp. 096739112110080

Author(s):

Yelda Meyva Zeybek ◽

Cevdet Kaynak

Keyword(s):

Functional Group ◽

Filler Content ◽

Mechanical And Thermal Properties ◽

Screw Extruder ◽

Melt Mixing ◽

Grafted Copolymer ◽

Before And After ◽

Twin Screw ◽

Oligomeric Silsesquioxane ◽

Matrix Nanocomposites

The main purpose of this study was to investigate influences of three parameters on the mechanical and thermal properties of the polylactide (PLA) matrix nanocomposites filled with polyhedral oligomeric silsesquioxane (POSS) particles. For the first parameter of “Filler Content”, nanocomposites with 1, 3, 5, 7 wt% basic POSS structure were compared. For the second parameter of “Functional Group,” basic POSS structure having only nonpolar isobutyl groups were compared with three other functionalized POSS structures; i.e. aminopropylisobutyl-POSS (ap-POSS), propanediolisobutyl-POSS (pd-POSS) and octasilane-POSS (os-POSS). Finally, for the third parameter of “Copolymer Compatibilization,” all specimens were compared before and after their maleic anhydride (MA) grafted copolymer compatibilization. Specimens were produced with twin-screw extruder melt mixing and shaped under compression molding. Various tests and analyses indicated that the optimum filler content for the improved mechanical properties was 1 wt%; while the optimum structure for strength and modulus was pd-POSS structure, in terms of fracture toughness it was basic POSS structure. Additional use of MA compatibilization was especially effective for the basic POSS and os-POSS particles.

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The structure, composition and preparation of injection-molded composite materials based on glass-filled polysulfone

Тонкие химические технологии ◽

10.32362/2410-6593-2019-14-4-39-44 ◽

2019 ◽

Vol 14 (4) ◽

pp. 39-44

Author(s):

A. B. Baranov ◽

T. I. Andreeva ◽

I. D. Simonov-Emelʼyanov ◽

O. E. Peksimov

Keyword(s):

Composite Materials ◽

Glass Fiber ◽

Glass Fibers ◽

Critical Length ◽

Fiber Concentration ◽

Extrusion Head ◽

Short Glass Fiber ◽

Twin Screw ◽

Time Optimal ◽

Short Glass

In the course of this study, compositions and designed structures for the polysulfone (PSF) and short glass fibers systems were calculated. Additionally, disperse-filled polymer composite materials (DFPCM) based on PSF-190 were classified in accordance with their respective structures, and the optimal amount of glass fiber (13.5–18.5 vol %) was determined. This article describes the production of DFPCM using PSF and a short glass fiber with a twin-screw extruder (Labtech Engineering Company LTD, model Scientific FIC 20-40). Furthermore, optimal mixing parameters for the creation of composites wherein the glass fiber length exceeds the critical length (lcr) were established. The critical length was calculated, and the curves for fiber size distribution of polysulfone composites were depicted, and a difference in fiber concentration between the dispenser and the extrusion head (up to ~10–15%) was found when the fiber content was at 18–25 vol %. For the first time, optimal parameters (which pertain to medium-filled dispersions) for the structure of DFPCM based on PSF and short glass fiber are able to be demonstrated.

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Effect of Compatibilizers on Mechanical Thermal and Morphology Properties of HDPE/TiO2 Nanocomposites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.93-94.169 ◽

2010 ◽

Vol 93-94 ◽

pp. 169-172

Author(s):

N. Wiriyanukul ◽

S. Wacharawichanant

Keyword(s):

Tensile Strength ◽

Electron Microscope ◽

High Density Polyethylene ◽

Morphological Properties ◽

Screw Extruder ◽

Melt Mixing ◽

Before And After ◽

Twin Screw ◽

Dispersion Of Nanoparticles ◽

Scanning Electron

This work studies the effect of PE-g-MA compatibilizer on mechanical thermal and morphological properties of high density polyethylene (HDPE)/titanium dioxide (TiO2) nanocomposites. The HDPE/TiO2 nanocomposites with and without PE-g-MA compatibilizer were prepared by melt mixing technique in a twin screw extruder. The results found that Young's Modulus of HDPE/TiO2 nanocomposites increased with increasing TiO2 contents. The addition of PE-g-MA compatibilizer had no significant effect on the tensile strength and stress at break of HDPE/TiO2 nanocomposites. The decomposition temperatures of HDPE/TiO2 nanocomposites before and after adding PE-g-MA compatibilizer increased with increasing TiO2 contents. The dispersion of TiO2 nanoparticles in HDPE matrix was observed by scanning electron microscope (SEM). The dispersion of nanoparticles in HDPE matrix with PE-g-MA compatibilizer was relatively good, only a few aggregates exited.

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Studies on Tensile Properties of Compatibilized and Uncompatibilized Low-Density Polyethylene/Jackfruit Seed Flour (LDPE/JFSF) Blends at Different JFSF Content

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.264.120 ◽

2017 ◽

Vol 264 ◽

pp. 120-123 ◽

Cited By ~ 27

Author(s):

Sung Ting Sam ◽

Omar Sabbar Dahham ◽

Pei Gie Gan ◽

N.Z. Noimam ◽

Jingi Y. Kuan ◽

...

Keyword(s):

Tensile Properties ◽

Adipic Acid ◽

Morphological Properties ◽

Screw Extruder ◽

Direct Introduction ◽

Elongation At Break ◽

Seed Flour ◽

Before And After ◽

Twin Screw ◽

Natural Fillers

Currently, natural fillers seem to be the suitable materials in polymer industry, which have emerged as a viable and abundant replacement for the relatively high-cost and non-renewable conventional fillers. However, the direct introduction of natural fillers into polymer matrix could effect negatively on some properties. Therefore, the aim of this work is to evaluate the influence of jackfruit seed flour (JFSF) (before and after compatibilization) on the tensile properties of (LDPE/JFSF) blends. Different JFSF content (5, 10, 15 and 20 wt.%) with (63-100 𝜇𝑚) particle size were prepared in this work. Twin-screw extruder at 150°C and 50rpm screw speed followed by hot-compress machine at 150°C and 10MPa pressure were used respectively to produce (LDPE/JFSF) blends. Adipic acid (AA) solution was added as a compatibilizer into all blends equally (25wt% AA into 75wt% JFSf). The changes of tensile and morphological properties were investigated. Results shown decreasing on tensile strength and elongation at break of LDPE/JFSF and LDPE/JFSF/AA as JFSF increased. In contrast, Young’s modulus increased up to 10 wt.% of JFSF and then decreased. However, the addition of Adipic acid, particularly for JFSF 5wt.% has improved the tensile properties of LDPE/JFSF blends. The SEM micrographs showed the agglomeration at high JFSF content (20 wt%) which in turn effected negatively on the tensile properties. However, the blends show homogeneous surfaces as AA added.

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Preparation of Biodegradable Materials by Reactive Extrusion

Materials Science Forum ◽

10.4028/www.scientific.net/msf.587-588.520 ◽

2008 ◽

Vol 587-588 ◽

pp. 520-524 ◽

Cited By ~ 6

Author(s):

Isabel Moura ◽

Ana Vera Machado ◽

Fernando M. Duarte ◽

Gabriela Botelho ◽

Regina Nogueira

Keyword(s):

Mechanical Properties ◽

High Density Polyethylene ◽

Young Modulus ◽

Polymeric Materials ◽

Reactive Extrusion ◽

Biodegradable Materials ◽

Screw Extruder ◽

Elongation At Break ◽

Twin Screw ◽

Poly Caprolactone

This work aimed to prepare biodegradable polymeric materials based on blends of a synthetic high density polyethylene (HDPE) and biodegradable polymers such as polylactic acid (PCL) and poly(caprolactone) (PLA), in a co-rotating twin-screw extruder. A polyethylene modified with maleic anhydride was used as compatibiliser. The mechanical results showed that the addition of PLA improves the blends stiffness while the addition of PCL leads to materials with a greater elongation at break and a lower Young modulus. This feature is related with the mechanical properties of each material as well as the adhesion between them. Concerning the biodegradability tests, it was found that HDPE/PCL blend presents the highest degree of biodegradability.

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Determination of the phase structure of polymerblends by electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100109604 ◽

1978 ◽

Vol 36 (1) ◽

pp. 492-493

Author(s):

Dr. G. Kaemof

Keyword(s):

Screw Extruder ◽

Electron Microscopic ◽

Thin Sections ◽

Single Screw Extruder ◽

Transmission Electron ◽

The Matrix ◽

Twin Screw ◽

Special Case ◽

Microscopic Investigations

A mixture of polycarbonate (PC) and styrene-acrylonitrile-copolymer (SAN) represents a very good example for the efficiency of electron microscopic investigations concerning the determination of optimum production procedures for high grade product properties.The following parameters have been varied:components of charge (PC : SAN 50 : 50, 60 : 40, 70 : 30), kind of compounding machine (single screw extruder, twin screw extruder, discontinuous kneader), mass-temperature (lowest and highest possible temperature).The transmission electron microscopic investigations (TEM) were carried out on ultra thin sections, the PC-phase of which was selectively etched by triethylamine.The phase transition (matrix to disperse phase) does not occur - as might be expected - at a PC to SAN ratio of 50 : 50, but at a ratio of 65 : 35. Our results show that the matrix is preferably formed by the components with the lower melting viscosity (in this special case SAN), even at concentrations of less than 50 %.

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