• Composites Research
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• v.36 no.2
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• pp.86-91
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• 2023

Thermoplastic polyurethane (TPU) is a material whose mechanical properties change according to the phase separation of its unique internal microstructure and is therefore used in various industries. Use of TPU as composites helps in improving the desirable characteristics and properties in accordance with usage. Eco-friendly fillers one of the fillers are on the rise and those are mostly used for reinforcing role. Suberin, which can be extracted from cork, is the main component of cork. It is known to serve high damping property of elastomer composite. The original chemical structure of Suberin is an aliphatic polyester aggregate. In this research, Suberin is obtained after depolymerization into an oligomer having 2 or 3 ester bonds through alkaline hydrolysis. The extracted suberin was added to the matrix which is thermoplastic polyurethane as an eco-friendly filler for improving vibration damping property. As a result, when 10 wt% of suberin was added into thermoplastic polyurethane the existing trade-off relationship was overcome. And it is attained the elastic modulus and damping factor at room temperature improving 92 and 59%, respectively, compared to the original matrix. Those results are from the interaction between the microstructure of TPU and suberin.

• Proceedings of the Korean Fiber Society Conference
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• 1997.10a
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• pp.126-130
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• 1997

A series of Thermoplastic polyurethane elastomers was prepared via a two-step polymerization process. The NCO/OH feed ratio of polyurethane synthesized in this study was varied from 1 to 1.3. Studies have been made on the effects of chemical and physical cross-linkina, and the properties of thermoplastic polyurethane elastomers based on isophorone diisocyanate (IPDI)/1,4-butanediol (BD)/poly(propylene glycol) (PPG, MW:2000), isophorone diisocyanate (IPDI)/BD /poly(oxytetramethylene) glycol (PTMG, MW:2000) was compared. These materials were characterized using FTIR spectrometer, dynamic mechanical thermal analyzer, and tensile retraction tester. PTMG based polyurethane elastomers showed higher elasomeric behavior than PPG based polyurethane elastomers at the same NCO/OH ratio. This feature has been connected with the specific nature of the polyols. The permanent set(%) was decreased with increasing maximum elongation from 50% to 300%.

• 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 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.

• The korean journal of orthodontics
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• v.45 no.5
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• pp.268-272
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• 2015

Clear thermoplastic retainers have been widely used in daily orthodontics; however, they have inherent limitations associated with thermoplastic polymer materials such as dimensional instability, low strength, and poor wear resistance. To solve these problems, we developed a new type of clear orthodontic retainer that incorporates multi-layer hybrid materials. It consists of three layers; an outer polyethylenterephthalate glycol modified (PETG) hard-type polymer, a middle thermoplastic polyurethane (TPU) soft-type polymer, and an inner reinforced resin core. The resin core improves wear resistance and mechanical strength, which prevent unwanted distortion of the bucco-palatal wall of the retainer. The TPU layer absorbs impact and the PETG layer has good formability, optical qualities, fatigue resistance, and dimensional stability, which contributes to increased support from the mandibular dentition, and helps maintain the archform. This new type of vacuum-formed retainer showed improved mechanical strength and rate of water absorption.

• 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.

• Journal of Conservation Science
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• v.37 no.1
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• pp.55-62
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• 2021

This study investigated mechanical property changes by measuring compression factors, resilience, and compressive strength according to packaging pattern and filling rate to identify the applicability of cultural heritage packaging using thermoplastic polyurethane elastomers (TPU). Research results indicate that the cross-shaped 3D pattern showed the best resilience when the internal filling rate was 20%, while the octet pattern was the best when the filling rate was either 40 and 60%. The octet pattern had the best mechanical properties and stability with resistance capacities of 20.79 kgf/cm², 40.40 kgf/cm², and 82.23 kgf/cm² at 38%, 39%, and 40% recovery speeds, respectively, depending on the internal filling rate (20, 40, 60%). Based on these results, basic data on the applicability, stability, and reliability of 3D cultural heritage packaging materials using TPU materials were obtained.

• Journal of Adhesion and Interface
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• v.12 no.1
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• pp.11-15
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• 2011

In this study we synthesized low VOC-solvent soluble thermo plastic polyurethane, The effect of chain extender and NCO/OH ratio for properties of thermoplastic polyurethane was investigated. Also, we prepared low VOC-type primer by TPU and acrylic modified tackifier resin. When NCO/OH ratio was 2 or more, TPU was insoluble in low VOC solvent. And peel strength was higher value using polar type tackifier than non-ploar type tackifier.

• Proceedings of the Korean Fiber Society Conference
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• 1996.10a
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• pp.465-467
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• 1996

A series of thermoplastic polyurethane copolymers were prepared from polypropyleneglycol(PPG, MW 3000), 1,4-butanediol, Isophorone diisocyanate(IPDI) and dibutyltin dilaurate(BBT) as catalyst. Studies have been made on the effects of molar ratio of isocyanate /polyol/chain extender on the properties such as tensile and thermal properties. By varying the ration of hard to soft segments, TPU ranging from soft elastomeric polymer to relatively hard elastoplastics and be obtained. The storage modulus and glass transition temperature of TPU increased with increasing the hard segment content.

• Elastomers and Composites
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• v.35 no.3
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• pp.227-235
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• 2000

This study focused on the recycling technology and application of waste polyurethane scrap($5{\sim}7mm$) and waste urethane form from the footware scrap. Firstly we suggest the waste polyurethane can be used as a component of medium for hydroponic rose culture. Secondly, recycled thermoplastic polyurethane(RTPU) was produced and blended it with high impact polystyrene(HIPS). And also, in order to extend application of recycling field, the former was produced with adding the amine foaming agent to RTPU/HIPS alloy. The main purpose of this study is to diverse of the recycling of the waste polyurethane.