• Title/Summary/Keyword: 에틸렌초산비닐

Search Result 8, Processing Time 0.025 seconds

Influence of Chemical composition of Ethylene-Vinyl Acetate Copolymers on Impact Noise Damping of Composites (에틸렌-초산비닐 공중합체의 공중합 조성이 복합체의 충격음 흡수성능에 미치는 영향)

  • 이현종
    • Journal of Korea Foresty Energy
    • /
    • v.18 no.2
    • /
    • pp.55-61
    • /
    • 1999
  • This study was carried out to investigate the influence of viscoelastic properties(or chemical composition) of a series of ethylen-viny1 acetate copolymers on impact noise and vibration damping of wood/polymer/wood sandwich composites. The impact noise and vibration damping of composites were very sensitive to the state of molecular motion of polymer. The noise and vibration damping of composites were maximum when the polymer was under the glass transition(vinylacetate 55~75%) at the test-temperature, and minimum rubbery state(vinyl-acetate 47~20%) or glassy state(vinylacetate 100~87%). The polymer under glass transition reduced the impact noise by 6~12 dB.

  • PDF

Airtightness performance evaluation of ultra-high performance concrete using polymer coating materials (그래핀을 활용한 폴리머 도막재료의 물리적 특성 평가)

  • Lee, Hyun Seung;Kim, Kang Min;Yoon, Seob;Seo, Tae Suk
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2023.11a
    • /
    • pp.257-258
    • /
    • 2023
  • In this study, it was conducted to improve the physical properties of VAE polymer matrix used as a coating material. A nanocomposite was manufactured using graphene as a reinforcing agent based on a VAE matrix. As a result, improvements in tensile strength, adhesion strength, and porosity were confirmed.

  • PDF

Preparation of a Novel PU-LMO Adsorbent by Immobilization of LMO on Polyurethane Foam for Recovery of Lithium Ions (폴리우레탄 폼에 LMO를 고정화하여 리튬이온 회수를 위한 새로운 PU-LMO 흡착제의 제조)

  • You, Hae-Na;Lee, Min-Gyu
    • Clean Technology
    • /
    • v.20 no.3
    • /
    • pp.277-282
    • /
    • 2014
  • In this study, PU-LMO was made by immobilization of LMO on urethane foam (PU) with using an EVA as a binder. PU-LMO was characterized by using X-Ray Diffractometer (XRD) and Scanning Electron Microscopy (SEM). The optimal ratio of EVA/LMO for preparation of PU-LMO was 0.26 gEVA/gLMO. The adsorption of lithium ions by PU-LMO was found to follow the pseudo-second-order kinetic model. The equilibrium data fitted well with Langmuir isotherm model and the maximum removal capacity of lithium ions was 17.09 mg/g. The PU-LMO was found to have a remarkably high selectivity of lithium ions and high adsorption capacity because the distribution coefficient ($K_d$) of lithium ion was higher than those of other metal ions.

Release of 5-Fluorouracil from Ethylene-Vinyl Acetate Matrices Containing Hydrophilic Additives (수용성 첨가제를 함유하는 에틸렌초산비닐 매트릭스로부터 5-플루오로우라실의 방출)

  • Oh, Seaung-Youl;Yoo, Young-Mee;Kim, Sung-Soo;Shin, Byung-Chul;Yuk, Soon-Hong;Lee, Hai-Bang
    • Journal of Pharmaceutical Investigation
    • /
    • v.26 no.4
    • /
    • pp.281-289
    • /
    • 1996
  • In our previous work, we have studied the effect of lactose and sodium alginate (SA) on the rate of release of 5-fluorouracil (5-FU) from ethylene-vinyl acetate (EVA) matrix. These hydrophilic additives promoted the rate of 5-FU release and the increase in rate was larger when SA was used. Both additives showed better ability to increase the rate than 5-FU itself. In this paper, we extended our study to another hydrophilic additive, Carbopol 940 (CP). Compared to SA or lactose, CP increased the rate of 5-FU release markedly. Release rate increased as the loading amount and the pH of the release medium increased. After release experiment, matrix volume increased up to 15 times of that before release experiment, depending on the amount of CP dispersed in the matrix and the pH of the release medium. On the other hand, the volume of the matrix containing lactose or SA decreased. The weight changes of the dry matrix before and after release experiment imply that CP is not released out of the matrix, to the contrary of lactose and SA. Scanning electron microscope study clearly showed that large cavities and pores are generated on the surface and the inside of the matrix. These results indicate that the mechanism by which CP increases the release rate is quite different from that of monomeric additives such as lactose or SA.

  • PDF

Durability of Ultrarapid-Hardening Polymer-Modified Mortar Using Redispersible Polymer Powder (재유화형 분말수지 혼입 초속경 폴리머 시멘트 모르타르의 내구성)

  • 이윤수;주명기;연규석;정인수
    • Journal of the Korea Concrete Institute
    • /
    • v.14 no.5
    • /
    • pp.660-667
    • /
    • 2002
  • The effects of polymer-cement ratio and antifoamer content on the durability of ultrarapid-hardening polymer-modified mortars using redispersible polymer powder are examined. As a result, regardless of the antifoamer content, the setting time of the ultrarapid-hardening polymer-modified mortars using redispersible polymer powder tend to delay with increasing polymer-cement ratio. The water absorption and chloride ion penetration depth of the ultrarapid-hardening polymer-modified mortars using redispersible polymer powder decrease with increasing polymer-cement ratio and antifoamer content. The resistance of freezing and thawing and chemicals improvement is attributed to the improved bond between cement hydrates and aggregates because of the incorporation of redispersible polymer powder

Durability of High-fluidity Polymer-Modified Mortar Using Redispersible Polymer Powder (재유화형 분말수지 혼입 고유동 폴리머 시멘트 모르타르의 내구성)

  • Joo Myung-Ki;Lee Youn-Su;Youn Do-Yong;Jung In-Su
    • Journal of the Korea Concrete Institute
    • /
    • v.17 no.5 s.89
    • /
    • pp.703-708
    • /
    • 2005
  • The effects of polymer-cement ratio and antifoamer content on the setting time and durability of high-fluidity polymer-modified mortars using redispersible polymer powder are examined. As the result, the setting time of the polymer-modified mortars using redispersible polymer powder tends to be delayed with increasing polymer-cement ratio, regardless of the antifoamer content. The water absorption, chloride ion penetration depth and carbonation depth of the high-fluidity polymer-modified mortars using redispersible polymer powder decrease with increasing polymer-cement ratio and antifoamer content. The resistance of freezing and thawing and chemicals improvement is attributed to the improved bond between cement hydrates and aggregates because of the incorporation of redispersible polymer powder

Physicochemical Characteristics and Efficacy of Controlled-release Insecticide Formulation (방출조절형(放出調節型) 살충성(殺蟲性) 농약제제(農藥製劑)의 특성(特性)과 약효(藥效)에 관한 연구(硏究))

  • Kim, Jin-Hwa;Oh, Byung-Youl;Oh, Kyeong-Seok;Kim, Sung-Kee;Kim, Mee-Hea;Kim, Young-Koo
    • Korean Journal of Environmental Agriculture
    • /
    • v.14 no.3
    • /
    • pp.289-295
    • /
    • 1995
  • This study was carried out to develop a controlled-release insecticide formulation for the control of rose aphid (Macrosiphum ibarae) in rose and cotton aphid (Myzus persicae) in chrysanthemum (Dendranthema grandiflorum var. Meibung) in greenhouse. Imidacloprid[1-(6-chloro-3-pyridylmethyl)-N-nitroimidazolidin-2-ylideneamine] was chosen as a toxicant. Two synthetic polymers, low density polyethylene(LDPE) and ethylene vinyl acetate(EVA), were used as polymer matrices. The tested plastic sheet formulations were prepared by heat-aided extrusion procedures after mixing imidacloprid technical and the polymers of three different combinations, and physicochemical properties as well as efficacy of the formulations were investigated. The amounts of imidacloprid recovered and incorporated in the formulations were recorded over 90% and 80%, respectively. Release of the active ingredient from the formulations was remarkably affected by mixing rates of polymers. The active ingredient in the formulations was chemically unstable with over 10% degradation rates after 90 day storage at $50{\pm}2^{\circ}C$. The residual amounts of imidacloprid in the soil treated with the formulations were paralleled with the release pattern of the formulations. Efficacy of the formulations on rose and cotton aphid was maintained over 90% even 120days after treatment under greenhouse.

  • PDF

Studies on the Substance of Migration for Retort Pouch Packaging Materials for Various Condition (레토르트 파우치 포장재의 사용조건에 따른 이행물질의 조사)

  • Lee, Man-Sul;Song, Beum-Ho;Park, Sun-O;Lee, Bu-Young;Lee, Young-Za;Youn, Hey-Kyung;Eum, Mi-Ok;Seung, Ju-Heung;Jeun, Dae-Hoon
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
    • /
    • v.13 no.3_4
    • /
    • pp.107-112
    • /
    • 2007
  • The effect of microwave heat to retort pouches and microwavable packages was examined. 186 products were collected, but packages were consisted of five package materials such as PET, Aluminum foil, Nylon, EVOH, and polypropylene. The results showed that all packages did not exceed the limits of current packaging regulation on consumption weight of $KMnO_4$, TDI(Toluene diisocyanate), and Caprolactam. Safety control on heat resistant packages considered satisfactory, but investigation on new substances should be continued for preventing any possible migration problems of packaged foods.

  • PDF