• Title, Summary, Keyword: Adhesion Properties

Search Result 1,532, Processing Time 0.053 seconds

Properties of Blood Compatible Crosslinked Blends of $Pellethene^{(R)}$/Multiblock Polyurethanes Containing Phospholipid Moiety/C-18 Alkyl Chain

  • Yoo, Hye-Jin;Kim, Han-Do
    • Macromolecular Research
    • /
    • v.16 no.7
    • /
    • pp.596-603
    • /
    • 2008
  • To improve the mechanical properties, dimensional stability and blood compatibility, the biomedical material $Pellethene^{(R)}$ was blended with multiblock polyurethane (MPU) containing phospopholipid/long alkyl chain (C-18) at the various MPU contents and crosslinked using dicumyl peroxide as a crosslinking agent. The maximum MPU content for stable $Pellethene^{(R)}$/MPU blended films was approximately 30 wt%. The optimum crosslinking agent content and crosslinking time with respect to the mechanical properties were 4 wt% and 3 h, respectively. The mechanical properties (tensile strength and elongation at break) and water absorption of the crosslinked blend film increased with increasing MPU content. The test of platelet adhesion on the surfaces of the crosslinked blend film showed a decrease in the level of platelet adhesion from 70% to 6% with increasing MPU content from 0 to 30 wt%. These results suggest that the crosslinked $Pellethene^{(R)}$/MPU-30 (MPU content: 30 wt%) sample has strong potential as a novel material for blood compatible material applications.

The PSA Properties of n-Butyl Acrylate/Acrylic Acid Copolymer and Tackifier Resins with Influence of Miscibility (n-Butyl Acrylate/Acrylic Acid 공중합체와 점착부여제간의 상용성과 점착물성)

  • 민경은;김호겸;최관영;곽기호
    • Polymer(Korea)
    • /
    • v.24 no.4
    • /
    • pp.469-476
    • /
    • 2000
  • The miscibility between acrylic copolymers and tackifier resins influenced on adhesion properties of PSA. PSA with high molecular weight and narrow molecular weight distribution of acrylic copolymers showed systemical modification of adhesion properties of PSA by tackifier resins only in case of miscible system. It is concluded that the investigation of the miscibility between two Components is very important to adhesion properties of PSA.

  • PDF

Functional hyaluronic acid conjugates based on natural polyphenols exhibit antioxidant, adhesive, gelation, and self-healing properties

  • Halake, Kantappa;Lee, Jonghwi
    • Journal of Industrial and Engineering Chemistry
    • /
    • v.54
    • /
    • pp.44-51
    • /
    • 2017
  • Polyphenols are naturally occurring compounds found in fruits and vegetables. They are bulky molecules comprising of hydroxyl groups in the forms of catechol and other phenolic groups. The catechol functionality is believed to be responsible for the adhesive and cross-linking characteristics. Natural polyphenols were grafted onto hyaluronic acid (HA) using epichlorohydrin chemistry, and the successful preparation of novel HA conjugates were confirmed. The reduction potential of polyphenols was inversely related to the DPPH radical scavenging activity of the conjugates, which in turn was linearly related to the adhesion strength of the conjugates. Although polypropylene had no site for hydrogen bonding, the adhesion strength of the conjugates onto polypropylene reflected the numbers of hydroxyl and catechol groups in general. The adhesive strength of the conjugates increased by 20-fold compared to that of the native HA. Although, hesperidin has no catechol groups, it still improved the adhesion strength. Reversible coordination with metal ions facilitated ionic gelation and self-healing properties. Adhesive, antioxidant, gelation, and self-healing properties were successfully achieved simultaneously. These functional properties could make the natural conjugates promising candidates for biomedical applications and environmentally safe materials.

UV-curing Behaviors and Mechanical Properties of UV-cured Polylactic Acid (PLA)

  • Lee, Seung-Woo;Park, Ji-Won;Park, Cho-Hee;Kim, Hyun-Joong;Eom, Young-Geun
    • Journal of the Korean Wood Science and Technology
    • /
    • v.41 no.2
    • /
    • pp.134-140
    • /
    • 2013
  • UV curing was introduced via a chemical treatment by adding small amounts of a hexafunctional acrylic monomer and a photoinitiator to improve the mechanical properties of PLA. This study also employed a semi-interpenetrated structured polymer network through the process of UV-curing. The UV curing behaviors were investigated using FTIR-ATR spectroscopy and gel fraction determination. Also, the tensile strength was investigated with different hexafunctional acrylic monomer contents and UV doses. The results showed that the crosslinking of UV-induced chemically treated PLA started at a low content of hexafunctional acrylic monomer, resulting in a significant improvement of the mechanical properties compared to those of neat PLA due to crosslinking.

Micro/Nano Adhesion and Friction Properties of SAMs with Different Head and Functional Group according to the Coating Methods (코팅 방법에 따른 이종 SAMs의 관능기별 마이크로/나노 응착 및 마찰 특성)

  • Yoon Eui-Sung;Oh Hyun-Jin;Han Hung-Gu;Kong Hosung
    • Tribology and Lubricants
    • /
    • v.21 no.3
    • /
    • pp.107-113
    • /
    • 2005
  • Micro/nano adhesion and friction properties of self-assembled monolayers (SAMs) with different head- and end-group were experimentally studied according to the coating methods. Various kinds of SAM having different spacer chains (C10 and C18), head-group and end-group were deposited onto Si-wafer by dipping and chemical vapour deposition (CVD) methods under atmospheric pressure, where the deposited SAM resulted in the hydrophobic nature. The adhesion and friction properties between tip and SAM surfaces under nano scale applied load were measured using an atomic force microscope (AFM) and also those under micro scale applied load were measured using a ball-on-flat type micro-tribotester. Surface roughness and water contact angles were measured with SPM (scanning probe microscope) and contact anglemeter respectively. Results showed that water contact angles of SAMs with the end-group of fluorine show higher relatively than those of hydrogen. SAMs with the end-group of fluorine show lower nano-adhesion but higher micro/nanofriction than those with hydrogen. Water contact angles of SAMs coated by CVD method show high values compared to those by dipping method. SAMs coated by CVD method show the increase of nano-adhesion but the decrease of nano-friction. Nano-adhesion and friction mechanism of SAMs with different end-group was proposed in a view of size of fluorocarbon molecule.

Comparative Analysis of Substrate Wet Surface Adhesion and Substrate Movement Response Performance Testing Methods for Injection Type Repair Materials Used in Leakage Cracks of Concrete Structure in Underground Environment (지하 습윤 환경에서 콘크리트 구조물 균열 누수에 사용되는 주입형 보수재료의 부착 성능과 거동 대응 성능 평가의 상관성 분석 연구)

  • Kim, Soo-Yeon;Oh, Kyu Hwan;Oh, Snag-Keun
    • Journal of the Architectural Institute of Korea Structure & Construction
    • /
    • v.34 no.9
    • /
    • pp.19-26
    • /
    • 2018
  • The focus of this study was centered around 15 common injection type water leakage repair materials (3 different types for each; synthetic polymer, cementitious, acrylic, epoxy, urethane) used in concrete structures of Korea and analyzing their wet surface adhesion performance in accordance to the ISO TS 16774 Test Method for Repair Materials for Water-leakage Cracks in Underground Concrete Structures, Part 4: Test Method for Adhesion on Wet Concrete Surface, and the results of this study was taken to be place under a comparative analysis with the results of the preceeding study on response to substrate movement performance study. The results of this comparative study showed that other than 1 specimen of 1 type of the acrylic and 3 specimens of 1 type of the synthetic polymer type materials, all of the 93% of the specimens used in this study showed stable adhesion on wet substrate surface, and we were able to determine that materials that have proper response properties against substrate movement are highly flexible and have high adhesion properties, but their adhesion properties on wet substrate would change based on their viscosity.

Studies on Adhesion Properties between Zinc-Coated Steel Cord and Adhesion Promoter-Containing Rubber Compound (아연 코팅된 스틸코드와 접착증진제가 적용된 고무 Compound와의 접착특성 연구)

  • Ko, Sang Min;Choi, Hee Seok;Son, Woo Jung;Kang, Sin Jung
    • Journal of Adhesion and Interface
    • /
    • v.15 no.2
    • /
    • pp.49-56
    • /
    • 2014
  • In this study, properties of adhesion between adhesion promoter-containing rubber compound and zinc coated steel cord was investigated. Cobalt salt, resorcinol formaldehyde resin (RF resin) and hexamethoxymethylmelamine (HMMM) were used to adhesion promoter. Since cobalt salts accelerate sulphidation rate of zinc at zinc coated steel cord surface, pullout force of rubber compound applying cobalt salts was increased compared to that of rubber compound without applying cobalt salts. Pullout force and rubber coverage of rubber compounds applying all adhesion promoters were superior because strong interlocking between rubber matrix increased modulus due to applying RF resin and HMMM and grown zinc sulfides at zinc coated steel cord surface.

Effect of Silane Coupling Agent on Thermal Stability and Adhesion Properties of DGEBF Epoxy Resin (실란 커플링제에 따른 DGEBF 계열 에폭시의 열안정성 및 접착특성 평가)

  • Lee, Dong Su;Lee, Seul-Yi;Min, Byung-Gak;Seo, Young Soo;Lee, Bong Han;Park, Soo-Jin
    • Polymer(Korea)
    • /
    • v.38 no.6
    • /
    • pp.787-790
    • /
    • 2014
  • In this work, the epoxy specimens were prepared from diglycidyl ether of bisphenol F (DGEBF) with silane coupling agents (3-glycidoxypropyl trimethoxysilane (GPTMS)) in different ratios. Thermal stability was studied in terms of polymer decomposition temperature (PDT), temperature of maximum rate of weight loss ($T_{max}$), integral procedural decomposition temperature (IPDT), and decomposition activation energy ($E_a$) using TGA analysis. Adhesion properties of epoxy composite specimens were measured by UTM (universal testing machine) at atmosphere temperature. In this result, the adhesion properties of DGEBF were improved by addition of silane coupling agents compared to non-treated epoxy resin. However, when the content of GPTMS agent is more than 10 phr, adhesion properties decreased with increasing GPTMS agent.

Properties of Inkjet and Screen Printed Circuits with Substrate Treatments

  • Lee, Min-Su;Kim, Yong-Uk;Kim, Yeong-Hun;Yu, Ui-Deok
    • Proceedings of the Materials Research Society of Korea Conference
    • /
    • /
    • pp.4.1-4.1
    • /
    • 2011
  • Recently, circuit printing technology has been considered as a promising alternative to conventional PCB fabrication, for it can greatly reduce the manufacturing costs. Even though printed circuit has many advantages over typical subtractive technology such as fewer processes, it has some disadvantages. The major problems are low adhesion and poor resolution. Efforts to overcome these problems have been mainly focused on ink developments with a limited success. And surface treatments showed some improvements. Therefore, various plasma treatments and primer coatings on plastic substrates have been tested. Plasma treatments using hydrocarbon gases including methane and propane improved the pattern quality of the inkjet printed circuit, which are further improved upon heating of substrate. On the other hand, there is little effect on the adhesion, which is improved only by a special primer coating. The adhesion of inkjet printed circuit has been increased more than 10 times upon treatment. As for the screen printed circuits, the overall effects are less significant since there is some organic binder in the ink. Nonetheless, the treatment has strong positive effects on pattern quality and adhesion. The adhesion of 1 kgf/cm2, which is comparable with those of the conventional PCB circuits, is possible through primer coating for both screen and inkjet printed circuits. The resulting circuit also showed good thermal, mechanical and electrical properties.

  • PDF