Weld Line Morphology in Injection-Molded General Purpose and High Impact Polystyrene

An induction heating and cooling mold that can keep the surface temperature of the entire mold cavity uniform and has a new heating and cooling insert with a gas vent mechanism is designed and produced. The effects of the temperature of the mold cavity surface, of the cavity air during the melt filling process, and of the organic gas generated fromthe melt on the appearance andmechanical properties of an injectionmolded product made of high impact polystyrene are studied. It is found that the heating and coolingmold with a gas vent can suppress molding defects, such as a weld lines and gas burns, and can greatly increase the displacement ratio of molded products obtained in the tensile test. This means that the effects of the gas vent and the surface temperature of the cavity have been quantitatively clarified using this type of mold.

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Measurements of the Stationary Viscoelastic Properties of General Purpose- and High Impact-Polystyrene Melts by Use of a Screwless Extruder

Journal of the Society of Materials Science Japan ◽

10.2472/jsms.22.1104 ◽

1973 ◽

Vol 22 (243) ◽

pp. 1104-1109

Author(s):

Kensei HAYASHIDA ◽

Hiroaki FUKUMOTO ◽

Akira YAMAGUCHI

Keyword(s):

Viscoelastic Properties ◽

General Purpose ◽

High Impact ◽

High Impact Polystyrene

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Analysis of Thermomechanical Properties of Selected Class of Recycled Thermoplastic Materials Based on Their Applications

Recycling ◽

10.3390/recycling4030033 ◽

2019 ◽

Vol 4 (3) ◽

pp. 33 ◽

Cited By ~ 2

Author(s):

Job Momanyi ◽

Michael Herzog ◽

Peter Muchiri

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Young’S Modulus ◽

Young's Modulus ◽

Industrial Applications ◽

General Purpose ◽

High Impact ◽

Scanning Calorimetry ◽

High Impact Polystyrene ◽

Recycled Polypropylene

Polypropylene and polystyrene are petroleum-based thermoplastics which are commonly used and disposed of in the environment after their service life, leading to environmental degradation. There is a need to recycle polypropylene and polystyrene, but the effect of recycling on thermo-mechanical properties is not well understood. This study aims to determine thermo-mechanical properties of the recycled polypropylene and recycled polystyrene and compare them with corresponding virgin polypropylene and newly produced polystyrene (general purpose polystyrene 1540 and high impact polystyrene 7240). The study was carried out by preparing bar-shaped samples of recycled polypropylene, recycled polystyrene, general purpose polystyrene 1540, and high impact polystyrene 7240 by compression molding using a hot press and thermally characterizing them to determine glass transition temperature and melting temperature using differential scanning calorimetry. The changes in Young’s modulus, tensile strength, hardness, and toughness due to recycling activities were determined at room temperature (24 °C), 40 °C, 60 °C, and 80 °C. The thermo-mechanical properties of recycled polystyrene (PS) were found to be comparable to those of high impact polystyrene (HIPS) 7240. The study revealed that the hardness and toughness for the recycled polymers were higher than those of corresponding virgin polymers. On the other hand, tensile strength and Young’s modulus for the recycled polymers were lower than those of the virgin polymers. Understanding the thermo-mechanical properties of the recycled polymers will contribute to more industrial applications hence increase the rate of recycling, resulting in a reduction in environmental pollution.

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Enhanced Wetting and Adhesive Properties by Atmospheric Pressure Plasma Surface Treatment Methods and Investigation Processes on the Influencing Parameters on HIPS Polymer

Polymers ◽

10.3390/polym13060901 ◽

2021 ◽

Vol 13 (6) ◽

pp. 901

Author(s):

Miklós Berczeli ◽

Zoltán Weltsch

Keyword(s):

Surface Treatment ◽

Plasma Treatment ◽

Atmospheric Pressure ◽

High Impact ◽

Plasma Parameters ◽

Plasma Surface ◽

Wetting Properties ◽

High Impact Polystyrene ◽

Process Modification ◽

Plasma Surface Treatment

The development of bonding technology and coating technologies require the use of modern materials and topologies for the demanding effect and modification of their wetting properties. For the industry, a process modification process that can be integrated into a process is the atmospheric pressure of air operation plasma surface treatment. This can be classified and evaluated based on the wettability, which has a significant impact on the adhesive force. The aim is to improve the wetting properties and to find the relationship between plasma treatment parameters, wetting, and adhesion. High Impact PolyStyrene (HIPS) was used as an experimental material, and then the plasma treatment can be treated with various adjustable parameters. The effect of plasma parameters on surface roughness, wetting contact angle, and using Fowkes theory of the surface energy have been investigated. Seven different plasma jet treatment distances were tested, combined with 5 scan speeds. Samples with the best plasma parameters were prepared from 25 mm × 25 mm overlapping adhesive joints using acrylic/cyanoacrylate. The possibility of creating a completely hydrophilic surface was achieved, where the untreated wetting edge angle decreased from 88.2° to 0° for distilled water and from 62.7° to 0° in the case of ethylene glycol. The bonding strength of High Impact PolyStyrene was increased by plasma treatment by 297%.

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Effect of Triaryl Phosphate, Zinc and Zinc Borate on Fire Properties of High Impact Polystyrene and High Impact Polystyrene-Polyphenylene Oxide Blend (Modified-Polyphenylene Oxide

Journal of Fire Sciences ◽

10.1177/073490419401200605 ◽

1994 ◽

Vol 12 (6) ◽

pp. 529-550 ◽

Cited By ~ 5

Author(s):

Ramazan Benrashid ◽

Gordon L. Nelson ◽

Donald J. Ferm

Keyword(s):

Flame Retardancy ◽

High Impact ◽

Zinc Borate ◽

Polyphenylene Oxide ◽

High Impact Polystyrene ◽

Smoke Generation ◽

Flame Retarded ◽

Rate Of Heat Release ◽

Fire Properties ◽

Phase Activity

Samples of m-PPO (virgin and flame retarded) and high impact polystyrene blended with zinc and zinc borate (2ZnO·3B2O3·3.5H 2O), were pre pared. The effect of triaryl phosphate on the flame retardancy of PPO-HIPS in conjunction with zinc and zinc borate was studied. For polystyrene zinc borate shows some reduction in smoke generation. Zinc, however does not show any effect on smoke generation for high impact polystyrene. Triphenyl phosphate shows minimal flame retardancy in HIPS which is not enhanced by zinc. Addition of zinc gives an increase in oxygen index for FR m-PPO, whereas zinc borate decreases the OI values. Zinc borate may sequester triaryl phos phate and thus eliminate its vapor phase activity. Zinc borate shows a signifi cant reduction in smoke generation and rate of heat release for m-PPO.

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