• Title, Summary, Keyword: Unsaturated Polyester

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An Experimental Study on Toughening of Unsaturated Polyester Mortar Using Polyuretane Liquid Rubber (폴리우레탄 액상고무를 이용한 불포화 폴리에스테르 모르터의 인성개선에 관한 실험 연구)

  • 박준철;배근철;박준호;최영준;김화중
    • Proceedings of the Korea Concrete Institute Conference
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    • pp.371-376
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    • 2001
  • The purpose of this study is to investigate toughening of unsaturated polyester resin by addition of polyuretane liquid rubber. In general, unsaturated polyester resin has strong brittleness in spite of its high strength Therefore; it is difficult to use unsaturated polyester mortar for the place where impact resistance is demanded. In this study, it was evaluated strength and Gf by using to polyurethane liquid rubber. As a result, the toughness of unsaturated polyester mortar was increased by polyuretane liquid rubber.

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Properties of Unsaturated Polyester Mortar Using Shale as Fine Aggregates (혈암을 잔골재로 사용한 불포화 폴리에스터 모르터의 특성)

  • 박준철;배근철;최영준;서인식;김화중;김영수
    • Proceedings of the Korea Concrete Institute Conference
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    • pp.129-134
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    • 2001
  • The purpose of this study is to investigate properties of unsaturated polyester mortar using the shale as find aggregates. To evaluate properties of unsaturated polyester mortar using crushed sand from Black shale, Red shale, Gray shale, we peformed the experiment according the F/B ratio of 25, 30, 35% and the volume of fine aggregate of 50, 53, 56%. The Result of this study is as follows. the strength of unsaturated polyester mortar is higher than those of river sand. The F/B ratio is higher and the volume of find aggregate is lower, the strength of unsaturated polyester mortar is higher

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Strength Properties of MMA-Modified Unsaturated Polyester Mortar (MMA 개질 불포화 폴리에스터 모르타르의 강도 특성)

  • Yeon, Kyu-Seok;Jo, Kyu-Woo;Choi, Jong-Yun;Jeong, Jung-Ho
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • pp.379-382
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    • 2003
  • In this study, methyl methacrylate (MMA)- modified unsaturated polyester mortar, in which the MMA was added to the unsaturated polyester resin, was developed for improving the early-age strength and the workability of the conventional polymer concrete, binder of which was the unsaturated polyester resin. Then the strength properties of the MMA-modified unsaturated polyester mortar were surveyed. The experimental results showed that early-age strength was greater when the MMA contents were increased in the range of $20{\sim}40%$, but the strength rather showed a tendency of decrease when the MMA contents was 50%.

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Preparation and Curing Properties of Unsaturated Polyester Resins Based on Depolymerized Poly(ethylene terephthalate) (해중합 PET를 이용한 불포화 폴리에스테르 수지의 제조 및 경화 특성)

  • 김준호;박찬준
    • Textile Science and Engineering
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    • v.35 no.2
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    • pp.85-91
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    • 1998
  • We investigated the possibility of using PET oligomers, which are made from PET waste by glycolysis, as the raw material for the synthesis of unsaturated polyester resin. The unsaturated and saturated polyester resins were synthesized from PET oligomer, propylene glycol, maleic anhydride and phthalic anhydride. The basic properties of these resins were analyzed and the curing characteristics were evaluated by DSC method. The reactivity of maleic anhydride to the glycols containing PET oligomer was higher than that of phthalic anhydride. Isothermal DSC method was properly applied to measure the curing reactivities of polyester resins, and the curing time of resin was decreased with increasing temperature. With the smaller ratio of glycol component to acid component in the reactants, we could prepare the unsaturated polyester resins of the higher molecular weight and the better curability.

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Effect of Radiation Intensity on Mechanical Properties of UV-cured Vinylester/Unsaturated Polyester Blend System (UV 경화가 비닐에스터와 불포화폴리에스터 블랜드 시스템의 물성 특성에 미치는 영향)

  • Lee, Jae-Rock;Kim, Young-Mi;Park, Soo-Jin
    • Proceedings of the Korean Society For Composite Materials Conference
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    • pp.269-272
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    • 2002
  • UV curing technology becomes important in various sectors of applications due to the high efficiency, environmental protection, and saving of energy. The effect of different proportion of vinylester (VE) and unsaturated polyester (UP) for VE/UP blend system was investigated in context of mechanical properties. The compositions of VE/UP blend were varied within 0:100, 20:80, 40:60, 60:40, 80:20, and 100:0 by weight percent. 1 wt% 1-hydroxy-cyclohexyl-phenyl-ketone was used as photoinitiator. The used intensity of UV light was in the range of $40~70 mW/\textrm{cm}^2$. The flexural strength of vinylester was not sensitive to the intensity of UV light. But the unsaturated polyester was very sensitive to the intensity of UV light. The flexural strength of vinylester was always superior to that of unsaturated polyester. The addition of the vinylester increased the flexural strength of blend system.

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Moisture Absorption Behavior of CNT Reinforced Unsaturated Polyester Composites (CNT 강화 불포화 폴리에스터 복합재료의 수분흡수 거동에 관한 연구)

  • Park, Ji-Hye;Yoon, Sung-Ho
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • pp.536-538
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    • 2011
  • In this study, the moisture absorption behaviors of the CNT reinforced unsaturated polyester composites were investigated along with exposure temperature and time. The tensile properties of the specimens were evaluated to identify the effect of absorbed moisture on the mechanical properties. The exposure temperatures of $25^{\circ}C$ and $75^{\circ}C$ were considered and the exposure time up to 600 hours was applied. According to the results, moisture absorption rate was increased as CNT content and exposure temperature were increased. The rate of decrease in tensile strength of the CNT reinforced unsaturated polyester composites was reduced due to the reinforcing effect of CNT compared to the unsaturated polyester resin.

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Fabrication and Electrical, Thermal and Morphological Properties of Novel Carbon Nanofiber Web/Unsaturated Polyester Composites

  • Kim, Seong-Hwan;Kwon, Oh-Hyeong;Cho, Dong-Hwan
    • Carbon letters
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    • v.11 no.4
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    • pp.285-292
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    • 2010
  • Novel unsaturated polyester composites with PAN-based nanofiber, stabilized PAN nanofiber, and carbonized nanofiber webs have been fabricated, respectively, and the effects of the nanofiber web content on their electrical resistivity, the thermal stability, dynamic storage modulus, and fracture surfaces were studied. The result demonstrated that the introduction of just one single layer (which is corresponding to 2 wt.%) of the carbonized nanofiber web to unsaturated polyester resin (UPE) could contribute to reducing markedly the electrical resistivity of the resin reflecting the percolation threshold, to improving the storage modulus, and to increasing the thermal stability above $350^{\circ}C$. The effect on decreasing the resistivity and increasing the modulus was the greatest at the carbonized PAN nanofiber web content of 8 wt.%, particularly showing that the storage modulus was increased about 257~283% in the measuring temperature range of $-25^{\circ}C$ to $50^{\circ}C$. The result also exhibited that the carbonized PAN nanofibers were distributed uniformly and compactly in the unsaturated polyester, connecting the matrix three-dimensionally through the thickness direction of each specimen. It seemed that such the fiber distribution played a role in reducing the electrical resistivity as well as in improving the dynamic storage modulus.

Preparation of Unsaturated Polyester-based Hybrid Gel-Coats Containing Urethane Acrylate and Their Coating Performance

  • Kim, Ji-Hee;Baek, Seung-Suk;Kim, Oh Young;Park, Dong Hyup;Hwang, Seok-Ho
    • Elastomers and Composites
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    • v.54 no.3
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    • pp.247-251
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    • 2019
  • Two different urethane acrylates (mono-acrylate and di-acrylate) were used to prepare unsaturated polyester-based hybrid gel-coats. The physical properties and surface characteristics of these gel-coats were investigated on the basis of the content and type of urethane acrylate. The set-to-touch time increased and the physical properties (surface hardness and tensile strength) decreased with an increase in the urethane acrylate content. However, the type of urethane acrylate did not affect these parameters. It was found that the optimal urethane acrylate content for the application of unsaturated polyester-based hybrid gel-coats is ~10 wt%.

The Properties of Fluidity and Compressive Strength of Unsaturated Polyester Polymer Concrete According to Replacement Ratio of Rapidly-Chilled Steel Slag Fine aggregate (급냉 제강 슬래그 잔골재 대체율에 따른 불포화 폴리에스테르 폴리머 콘크리트의 유동성 및 압축강도 특성)

  • Kim, Jae-Won;Seo, Jung-Pil;Sun, Joung-Soo;Chi, Duck-Jin;Hwang, Eui-Hwan;Kim, Jin-Man
    • Proceedings of the Korean Institute of Building Construction Conference
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    • pp.43-46
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    • 2007
  • This study dealt with the influence of the replacement ratio of rapidly-chilled steel slag on fluidity and compressive strength of unsaturated polyester polymer concretes. The rapidly-chilled steel slag used in this study, a by-product which is produced by refining pig iron during the manufacture of steel, was controled by a air-jet method which rapidly cools substance melted at a high temperature. Experimental results show that fluidity and compressive strength of unsaturated polyester polymer concretes increase with increasing replacement ratio of rapidly-chilled steel slag. Use of rapidly-chilled steel slag was found to be effective for improving fluidity and compressive strength of rapidly-chilled steel slag.

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Prediction of Compressive Strength of Unsaturated Polyester Resin Based Polymer Concrete Using Maturity Method (성숙도 방법을 이용한 불포화 폴리에스터 수지 폴리머 콘크리트의 압축강도 예측)

  • Choi, Ki-Bong;Jin, Nan Ji;Lee, Youn-Su;Yeon, Kyu-Seok
    • Journal of The Korean Society of Agricultural Engineers
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    • v.59 no.6
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    • pp.19-27
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    • 2017
  • This study investigated to predict the compressive strength of unsaturated polyester resin based polymer concrete using the maturity method. The test results show that the development of the compressive strength increased exponentially until an age of 24 hours. After 24 hours, the development of the compressive strength just increased gradually. This test result shows that the strength of unsaturated polyester resin based polymer concrete was developed mainly at the early age. Estimated datum temperature of unsaturated polyester resin based polymer concrete was $-20.67^{\circ}C$ which was much lower than of datum temperature ($-10^{\circ}C$) of Portland cement concrete. Also, this study result shows that the existing maturity index associated with Portland cement concrete was not applicable for polymer concrete because curing time of Portland cement concrete is different clearly with curing time of polymer concrete. The cause of different curing time was that there were different curing mechanisms between Portland cement concrete and polymer concrete. In order to best apply the experimental data to a model, CurveExpert Professional, the commercial software, was used to determine the predictive model regarding the compressive strength of unsaturated polyester resin based polymer concrete. As a result, Gompertz Relation or Weibull Model was an appropriate model as a predictive model. The proposed model can be used to predict the compressive strength, especially, it is more useful when the maturity is in the range between $40^{\circ}C{\cdot}h^{0.4}$ and $900^{\circ}C{\cdot}h^{0.4}$.