• Elastomers and Composites
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• v.45 no.3
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• pp.152-155
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• 2010

Olefinic thermoplastic elastomer and styrenic thermoplastic elastomer have broad hardness range, high flexibility, low density, and excellent recyclability. But, they are limited in applications due to their low elasticity and low operating temperature. To overcome these problems, olefin/styrene or olefin/$\alpha$-olefin copolymers have been developed. In this review, we described some examples of olefin/styrene or olefin/$\alpha$-olefin copolymer and introduced their properties. Although olefin/styrene or olefin/$\alpha$-olefin copolymer have various weaknesses, they have a great potential in the future.

• Journal of the Korean Society for Precision Engineering
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• v.24 no.2 s.191
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• pp.41-46
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• 2007

Recently, the study for filling imbalance in thermoplastic polymer has gradually been increased. However, it is hard to find the researches for filling imbalance of thermoplastic elastomer(TPE). The experiment of filling imbalance was conducted for the three kinds of thermoplastic vulcanizes(TPVs) in the mold with geometrically balanced runner system. In this experiment, the effects of the melt temperature and injection speed on the filling imbalance were investigated. To solve the filling imbalance, Runner Core pin(RC pin) in the experimental mold was adopted and it's effects was tested. In this paper, we present that the insert length of RC pin is dependent to each polymers for optimal filling balance.

• Journal of Adhesion and Interface
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• v.16 no.2
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• pp.63-68
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• 2015

We synthesized thermoplastic polyurethane elastomer containing carboxylic acid group and TPV (thermoplastic vulcanizate). We measured the mechanical, grip, debris, contact angle and adhesion properties according to introducing acid group in elastomer structure. Mechanical and wet slip properties were improved because of the hydrogen bonding by introduction of acid group. Also adhesion strength was increased as increasing of surface polarity by carboxylic acid group. The debris property of TPV made from TPU containing carboxylic acid group was improved.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.5 no.1
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• pp.27-32
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• 2006

Thermoplastic elastomer(TPE) has many advantages such as high flexibility, high elasticity and high elongation, etc. TPE is easily molded as plastic materials, therefore, many TPE parts are applied as home appliances and mechanical parts. However, its mechanical properties would be changed by injection molding conditions such as melt temperature, mold temperature, injection pressure and holding pressure, etc. In this study, the influences of the injection molding condition on the mechanical properties as tensile strength, hardness of thermoplastic vulcanizates(TPVs), which is one of the TPE, were investigated. By the injection molding experiment, the molding's tensile strength and hardness was influenced on the melt temperature and composition ratio of PP and EPDM. The morphology of moldings were shown by the scanning electron microscope.

• Transactions of Materials Processing
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• v.16 no.1 s.91
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• pp.36-41
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• 2007

Thermoplastic elastomer(TPE) can be recycled and molded such as commercial thermoplastic. Therefore TPE has being widely applied on automobile, household and etc. in these days. This study shows the variation of mechanical properties and shrinkage on TPE moldings for variation of injection molding conditions such as injection pressure, holding pressure, melt temperature, mold temperature and etc. Mechanical properties in relation to tensile strength, hardness and shrinkage in connection with precision dimension of part are investigated. The tensile strength and shrinkage of the experimental TPEs are mainly influenced by injection pressure and melt temperature. All injection molding conditions scarcely affect on hardness. To verify the variation of tensile strength and shrinkage, morphology of TPE molding was scanned by the SEM. The morphology showed that as the melt temperature increased, the rubber particles on the TPE became smaller and widely were dispersed. This behavior of rubber particles influenced on the increase of tensile strength.

• Journal of the Korean Society of Clothing and Textiles
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• v.46 no.6
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• pp.1074-1087
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• 2022

This study reports an optimization of a 3D printed wrist brace (WB) for various tilting angles (0°, 45°, 90°) of the re-entrant (RE) pattern and thickness (2 mm, 4 mm) using thermoplastic polyurethane (TPU) filaments and thermoplastic elastomer (TPE) filaments. The actual printing time, weight, Poisson's ratio, and tensile property of the manufactured samples were analyzed. The results confirmed that the actual printing time and weight increased with increasing thickness, regardless of the filament type. All tilting angles of the WB showed a negative Poisson's ratio (NPR), the largest of which appeared at 90°. The results of the tensile property analysis showed that a 90° tilting angle also had the largest value of elongation and stress. From these results, we conclude that the most suitable wrist brace is one in which the actual printing time is low, the weight is minimized to a thickness of 2 mm, and the tilting angle of the RE pattern is 90° for good shock absorption. The choice of filaments may be decided upon according to the user's preference, since the TPU is stiff and the TPE is elastic.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.9
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• pp.77-83
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• 2018

Thermoplastic elastomers are being used increasingly throughout industry owing to their superior properties, such as superior elasticity, formability, and recoverability. Currently, research related to thermoplastic elastomers is focused on the development of composite elastomers by combining with various materials and the development of equipment. On the other hand, in the field of small and medium sized companies, it is necessary to study not only the application of these new materials, but also the process conditions that enable the extrusion of thermoplastic elastomers in inexpensive uniaxial screwing equipment. If extrusion is performed in a single screw extruder, it is important to maintain a uniform thickness through process control of the extruder. This study examined the effects of the processing temperature, which is an extrusion process variable, on the formability of a tube in the thermoplastic elastomer TPE-800L uniaxial extrusion process. The nozzle zone temperature is the most important factor in the extrusion of thermoplastic elastomer TPE-800L; the most excellent moldability was confirmed at $165-170^{\circ}C$.

• Macromolecular Research
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• v.13 no.5
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• pp.441-445
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• 2005

Thermoplastic polyurethane elastomer (TPUe) fiber mats were successfully fabricated by electrospinning method. The TPUe fiber mats were subjected to a series of cycling tensile tests to determine the mechanical behavior. The electrospun TPUe fiber mats showed non-linear elastic and inelastic characteristics which may be due to slippage of crossed fiber (non-bonded or physical bonded structure) and breakage of the electro spun fibers at junctions (point-bonded or chemical bonding structure). The scanning electron microscopy (SEM) images demonstrated that the point-bonded structures of fiber mats played an important role in the load-bearing component as determined in loading-unloading component tests, which can be considered to have a force of restitution.

• Korean Chemical Engineering Research
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• v.46 no.1
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• pp.15-22
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• 2008

Polyolefin block copolymer has been taking a great deal of attention due to their great potential in polymer industry since a new metallocene catalytic method for producing polyolefin block copolymer was developed by Dow Chemicals. However, so far, there was no systematic study of olefin block copolymer. In this review, Linear polyolefin block copolymers, containing semicrystalline poly (ethylene) (E) blocks and a rubbery block as a thermoplastic elastomer, were investigated in the viewpoint of microphase separation mode, microstructure, deformation behavior, and molecular architecture.

• Journal of the Korea Institute of Military Science and Technology
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• v.12 no.5
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• pp.660-666
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• 2009

Thermoplastic polyurethane elastomer(PU-TPE) and energetic thermoplastic polyurethane Elastomer(E-PU-TPE) were prepared from Hexamethylene diisocyanate(HDI), 1,4-BD/AA ester polyol and glycidyl azide polymer(GAP-2400) as an energetic material by the addition polymerization. The PU-TPE and E-PU-TPE were characterized by FT-IR and GPC. Viscometer, DSC and UTM were used to investigate the viscose behavior with a various solvent, thermal properties and mechanical properties of PU-TPE and E-PU-TPE, which are of potential interest for the development of high performance binder of energetic solid propellants. It was found that $M_w$ of PU-TPE and E-PU-TPEs are over 100,000 and decreased with increase of GAP-2400 contents. $T_m$ and ${\Delta}H$ as thermal properties decreased and also tensile strength and elongation at break as mechanical properties decreased with increase of GAP-2400 contents.