• The Korean Journal of Rheology
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• v.10 no.2
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• pp.57-64
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• 1998

A pultrusion resin impregnation (PRI) die, which has been developed recently in our laboratory, was used to pre-pare various composite system. The continuous fiber reinforced composites of glass fiber/polypropylene(GFPP) and glass fiber/polyamide 6 (GFPA) were first manufactured by means of the PRI die and then cut into chopped pellets of predet-ermined length. These pellets and either virgin or modified thermoplastic resin were melt-mixed by a twin screw extruder to prepare GF/PA/PP and GF/PA/PPMA system. The mechanical properties of these blends were investigated and discussed in terms of their morphological observations. These preliminary results revealed that this new impregnation die could be suc-cessfully applied to produce prepregs suitavle for the final shaping process.

• Carbon letters
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• v.19
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• pp.47-56
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• 2016

In this study, the fracture behavior of a thermoplastic-modified epoxy resin reinforced with continuous carbon fibers for two levels of fiber-matrix adhesion was performed. A carbon fiber with commercial sizing was used and also treated with a known silane, (3-glycidoxy propyl trimethoxysilane) coupling agent. Toughness was determined using the double cantilever test, together with surface analysis after failure using scanning electron microscope. The presence of polysulfone particles improved the fracture behavior of the composite, but fiber-matrix adhesion seemed to play a very important role in the performance of the composite material. There appeared to be a synergy between the matrix modifier and the fiber-matrix adhesion coupling agent.

• Carbon letters
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• v.14 no.2
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• pp.76-88
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• 2013

Carbon fibers (CFs) have high service temperature, strength, and stiffness, and low weight. They are widely used as reinforcing materials in advanced polymer composites. The role of the polymer matrix in the composites is to provide bulk to the composite laminate and transfer load between the fibers. The interface between the CF and the resin matrix plays a critical role in controlling the overall properties of the composites. This paper aims to review the synthesis, properties, and applications of polymer matrices, such as thermosetting and thermoplastic resins.

• Proceedings of the KWS Conference
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• 2002.10a
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• pp.688-693
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• 2002

Adhesive bonding is becoming one of the popular joining techniques in metal industries, since it has some advantages over other techniques such as welding and diffusion bonding, e.g., any dissimilar metals are easily adhesive-bonded together. In this study, the experiments were carried out in order to provide the statistical data with strength evaluation methods: tension, shear and four-point bending tests for thermoplastic epoxy resin based adhesive-bonded metal joints. We should certificate on the probability of the adhesive strength that has the tendency of brittle fracture, the adhesive bonding strength between metals with thermoplastic adhesive has the best probability at four-point bending test. The strength testing method that has higher probability is four-point bending test, shear test and tensile test in order.

• Journal of Welding and Joining
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• v.16 no.2
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• pp.48-56
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• 1998

This study was performed to find the best bonding conditions by comparing mechanical properties in thermoplastic resin of polyethylene (PE) and polyamide (PA) adhesion. Following results were obtained from the tests with varying welding time and welding pressure. Satisfactory adhesion was executed in ultrasonic welding for the same materials of PE and PA. The best welding conditions were found to be welding time of 1 second, welding pressure of 250kPa for PE-PE weding, 2 second and 350kPa for PA-PA welding. Welding time and welding pressure end to increase with the increase of materials strength. Dissimilar materials were adhered when adhesion and ultrasonc welding were performed simultaneously. The observation of the structure of ultrasonic welding area with microscope showed differenticated structures between well adhered region and badly adhered region.

• Journal of Technologic Dentistry
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• v.46 no.1
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• pp.15-19
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• 2024

An ideal post material should have physical properties similar to those of dentin. Post materials with high elastic moduli may cause root fractures. This clinical report describes the treatment of a severely damaged tooth using a recently introduced material. Polyetherketoneketone (PEKK) is a semicrystalline high-performance thermoplastic polymer. PEKK is a promising material for custom post-and-core fabrication because of its elasticity close to that of dentin, good shock absorbance, machinability, and low cost. A laboratory scanner was used to digitize the conventional impression of a severely damaged maxillary right first molar. A custom PEKK post-and-core was designed and milled using computer-aided design and computer-aided manufacturing technology. Using the proposed technique, a custom PEKK post-and-core was fabricated accurately and human error was reduced. Restoration was luted with resin cement. Custom PEKK post-and-core restorations are a viable alternative for treating severely damaged teeth.

• Journal of Korean Society of Forest Science
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• v.60 no.1
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• pp.37-44
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• 1983

Thermoplastic aceton-formaldehyde resin adhesive was added as a modifier for urea-formaldehyde resin adhesive and its effects on plywood smear strength and wood failure were investigated. The results are summarized as follows: 1) The plywood shear strength and wood failure showed the highest values at $120^{\circ}C$ of hot plate temperature, but the values decreased according to the rise of addition ratio of aceton resin. 2) The variation of molar ratio of aceton resin had no effect on plywood shear strength and wood failure. 3) The plywood bonded by the addition of aceton resin showed lower values than those of urea resin bonding plywoods in shear strength and wood failure. Therefore, aceton resin was inadequate as a modifier of urea resin adhesive.

• Composites Research
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• v.37 no.3
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• pp.186-189
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• 2024

This study compared and evaluated the mechanical properties of carbon fiber reinforced thermoplastic polymer (CFRTP) mixed with nanofillers. After mixing various nanofillers such as Multi-wall carbon nanotube (MWCNT), Silicon oxide, Core shell rubber, and Aramid nanofiber with Polyamide 6 (PA6) resin, this is used as a matrix to create a carbon fiber reinforced composite material (CFRP) was manufactured and its physical properties were measured. Depending on the type and mixing ratio of nanofiller, tensile strength, inter-laminar shear strength (ILSS), and Izod impact strength were measured. In terms of tensile strength and impact strength, the highest values were obtained when mixing core shell rubber, however the ILSS was optimal when mixing less than 1 wt.% of silicon oxide.

• Applied Chemistry for Engineering
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• v.1 no.2
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• pp.124-132
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• 1990

In order to improve the mechanical properties and fracture toughness of HPT 1071/DDS system, poly(aryl etherimide) (PEI) was incorporated in the resin system. In HPT 1071/DDS system, mechanical properties of cured epoxy resins were not strongly dependent on the concentration of DDS curing agent strongly. In the case of HPT 1071/DDS/PEI system, the fracture toughness and flexural properties of epoxy resins increased with increasing the concentration of PEI. SEM micrographs of cured epoxy resin indicated that the phase separation occured at the low concentration of PEI in this system. In addition, investigation of the relationship between mechanical properties and the morphology of modified epoxy resin was undertaken in HPT 1071/DDS/PEI system.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2005.05a
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• pp.96-100
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• 2005

본 연구는 차세대 반도체 칩 패키징 재료로 검토되고 있는 열가소성 수지(Thermoplastic resin)의 사출 성형에 있어서의 불량과 그에 따른 해결책을 Visual Basic을 이용하여 전산 정보화함으로써 성형 불량 대책을 제공, Gate와 Runner를 최적화하는 지적 결정 시스템을 개발하였다. 체계적인 기술이 정립되어 있지 않는 플라스틱 성형의 문제점을 최소화하고 재료비 절감, 설계 납기일 단축, 제품 품질 향상을 그 목적으로 하고 있다.