Optical measurement of high-temperature melt flow rate

Abstract Three different types of polyethylene powders were flame sprayed onto pre-heated steel substrate previously coated by electrostatic spray system with a thin epoxy primer layer. Properties of the polyethylene (PE) powders, including powder density, particle size and melt flow rate (MFR) were measured in order to study their influence on the mechanical properties of the coating. The spray experiments started with optimization of spraying parameters. The main variables were pre-heating temperature of the substrate, temperature increase during spraying (influenced by the spraying distance), and thickness of the PE coatings. The laboratory tests performed for the coatings were coating characterization by microscopy and mechanical testing. Porosity and thickness of the coatings were determined by optical and stereo microscopy studies from polished cross-sectional samples. Hardness, impact strength, peel strength, and adhesive strength of the coatings were also investigated. Also some hot water sinking and heat cycling tests were performed. As a result from the present studies it can be concluded that powder properties have great influence on the mechanical properties of the final coating.

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Polyethylene-Matrix Composites with Halloysite Nanotubes with Enhanced Physical/Thermal Properties

Polymers ◽

10.3390/polym11050787 ◽

2019 ◽

Vol 11 (5) ◽

pp. 787 ◽

Cited By ~ 10

Author(s):

Janusz W. Sikora ◽

Ivan Gajdoš ◽

Andrzej Puszka

Keyword(s):

Impact Strength ◽

Flow Rate ◽

Softening Temperature ◽

Halloysite Nanotubes ◽

Low Density Polyethylene ◽

Low Density ◽

Melt Flow ◽

Polyethylene Matrix ◽

Melt Flow Rate ◽

Heat Deflection Temperature

The aim of the present work is to investigate the effect of halloysite nanotubes (HNT) on the mechanical properties of low-density polyethylene composites modified by maleic anhydride-grafted PE (PE-graft-MA). Polyethylene nanocomposites were prepared using an injection molding machine, Arburg Allrounder 320 C 500–170; the HNT content was varied at 0 wt %, 2 wt %, 4 wt % and 6 wt %, and the PE-graft-MA content was varied at 5 wt %. The composites were examined for their ultimate tensile stress, strain at ultimate stress, hardness, impact strength, melt flow rate, heat deflection temperature, Vicat softening temperature, crystallinity degree and phase transition temperature. It was found that the addition of halloysite nanotubes to low-density polyethylene (LDPE) led to an increased heat deflection temperature (HDT, up to 47 °C) and ultimate tensile strength (up to 16.00 MPa) while the Vicat softening temperature, strain at ultimate stress, impact strength and hardness of examined specimens slightly decreased. Processing properties of the materials specified by the melt flow rate (MFR) deteriorated almost twice. The results have demonstrated that the nanoparticles can reinforce enhance LDPE at low filler content without any considerable loss of its ductility, but only when halloysite nanotubes are superbly distributed in the polyethylene matrix.

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Study of Mechanical Properties and Morphology of PA 6/PO Blends Compatibilized by PO Grafted with Itaconic Acid

e-Polymers ◽

10.1515/epoly.2007.7.1.1418 ◽

2007 ◽

Vol 7 (1) ◽

Author(s):

Liu Xijun ◽

Jiang Zhaohua ◽

Zhu Wenming

Keyword(s):

Mechanical Properties ◽

Graft Copolymer ◽

Flow Rate ◽

Itaconic Acid ◽

Polyamide 6 ◽

Glass Temperature ◽

Melt Flow ◽

Melt Flow Rate ◽

Twin Screw ◽

The Impact

AbstractTwo different types of polyolefine (PO) grafted with itaconic acid as a reactive compatibilizer, polypropylene (PP) grafted with itaconic acid (PP-g-ITA) and high density polyethylene (HDPE) grafted with itaconic acid (HDPE-g-ITA), PP and HDPE grafted with copolymer of itaconic acid and styrene (PP-g-(ITA-St) and HDPE-g-(ITA-St)) were prepared by melt graft technique through reactive type twin-screw extruder. FT-IR and thermal analysis were used to characterize the structure of the graft copolymer. The graft ratio (GR) and melt flow rate (MFR) were determined by non-aqueous titration and melt flow rate analyzer. The effect of the concentration of monomer and initiator dosage on GR and MFR of graft copolymer were studied. Then polyamide 6 (PA 6) blends, PA 6/PP (PA 6/HDPE), that compatibilized with PP-g-ITA (HDPE-g-ITA) were prepared. The morphology of the blends was analyzed by SEM, DSC and Molau tests and the mechanical properties of which were characterized by tensile, impact, and bend tests. The results of mechanical property showed that the impact strength of blends was increased by 50% and 70% after PP-g-ITA and HDPE-g-ITA was used as compatibilizer, but the MFR of blends was decreased. The SEM photographs indicated that the accession of compatibilizer obviously improved binding state between two phases in blends, the size of dispersed phase was reduced evidently and the interface became indistinct. DSC results demonstrated that in the case of PP-g-ITA, glass temperature (Tg) of PA 6 matrix in blends was ascended, melt point (Tm) was improved a little, crystallinity (Xc) was decreased, Tm and Xc of PP phase was increased; With the accession of HDPE-g-ITA, Tm of PA 6 matrix and HDPE phase had almost no change, Xc of PA 6 matrix was decreased and Xc of HDPE phase was increased.

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Preparation and Property Study of PMMA/ASA Alloy

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.130-134.2383 ◽

2011 ◽

Vol 130-134 ◽

pp. 2383-2387

Author(s):

Guo Dong Tang ◽

Si Chen ◽

Yan Qin Shi ◽

Xu Wang

Keyword(s):

Flow Rate ◽

Melt Blending ◽

Dsc Analysis ◽

Melt Flow ◽

Scanning Calorimetry ◽

Melt Flow Rate ◽

Interface Phase ◽

Blending Method ◽

Method Effects ◽

The Impact

Polymethyl methacrylate (PMMA)/ acrylonitrile-styrene-acrylate terpolymer (ASA) alloy was prepared via melt blending method. Effects of ASA melt flow rate and PMMA/ASA ratio on mechanical property of the alloy were studied. It showed that when the high melt flow rate ASA was used, alloy’s tensile strength and flexural strength were little different from using low melt flow rate ASA, while the impact strength was significantly higher than the latter. Differential scanning calorimetry (DSC) analysis showed that a glass transition (Tg) platform emerged in low melt flow rate ASA at 48.5°C, which represented the Tg of the interface phase formed between SAN grafted acrylate rubber particles and SAN matrix. Scanning electron microscope (SEM) experiment further showed that when low melt flow rate ASA was used, alloy’s cross section was smooth which showed the characteristics of brittle fracture.

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