• Title/Summary/Keyword: Sodium tetraborate decahydrate

Search Result 3, Processing Time 0.017 seconds

Catechol-Chitosan Hydrogel: Scale-up Synthesis and Self-Healing Properties (카테콜-키토산 하이드로겔의 대용량 합성과 자가 치유 특성 분석)

  • Choi, Hoe Young;Ko, Haye Min
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2022.11a
    • /
    • pp.251-252
    • /
    • 2022
  • Chemical crosslinking is the most widely used method for hydrogel preparations. We prepared a hydrogel using chitosan catechol/polyvinyl alcohol and sodium tetraborate decahydrate (Na2B4O7·10H2O). The formation of hydrogels often presents inconsistent results and issues according to the reaction scale. Therefore, we measured and analyzed the self-healing property and viscoelasticity of hydrogels attributed to scale-up synthesis using a rheometer.

  • PDF

Rheological Characteristics of Chitosan-Catechol Hydrogel attributed Catechol Content (키토산-카테콜 하이드로겔의 카테콜 함유량에 따른 유변학적 특성 분석)

  • Bang, Eun Ji;Ko, Haye Min
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2022.11a
    • /
    • pp.249-250
    • /
    • 2022
  • In this study, two types of chitosan-catechol polymers (a-CP and b-CP) were synthesized and mixed with polyvinyl alcohol (PVA) and sodium tetraborate decahydrate (Na2B4O7·10H2O) to form hydrogels. The characteristics of these polymers were tuned by varying the pH during their syntheses, and their structures were characterized using nuclear magnetic resonance spectroscopy and ultraviolet-visible spectroscopy. Rheological and self-healing properties of hydrogels were evaluated. As a result, the viscoelastic modulus was improved due to the increased functional group content, and the self-healing property was excellent regardless of the functional group content.

  • PDF

Preparation and Surface-Active Properties of Vinyl Acetate Cotelomers (I) (비닐아세테이트 코텔로머의 제조 및 계면활성(I))

  • Lee, Eon-Pil;Kang, Se-Mi;Hwang, Dae-Youn;Jung, Young-Jin;Choi, Hae-Wook;Choi, Young-Ho;Lee, Jae-Ho
    • Fashion & Textile Research Journal
    • /
    • v.14 no.4
    • /
    • pp.677-683
    • /
    • 2012
  • 1-octanethiol and vinyl acetate telomers ($R_8S$-nVAc) were synthesized and hydrolyzed with sodium hydroxide subsequently, 1.2-epoxyhexane was then introduced to the telomers. In addition, we prepared cotelomers of multi-alkylated nonionic surfactants with a molecular structure of xRnMA-yVA (x; hydrophobic group, y; hydrophilic group, MA; methacrylic ester, VA; vinyl alcohol, R; and alkyl group) and cross-linked with sodium tetraborate decahydrate. Their active surface properties were investigated by several techniques such as surface tension, foaming property, and emulsification power measurements. The surface tension of $R_8S$-8.8VA decreased without the introduction of 1.2-Epoxy hexane, and the degree of emulsification and foaming abilities of $R_8S$-8.8VA increased without the introduction of 1.2-Epoxy hexane. However, the differences were insignificant. The epoxy groups were attached to a $R_8S$-8.8VA cotelomer with a limited variation of the active surface properties. The surface tension of $1.1R_6MA$-8.8VA decreased after cross-linking subsequently, the degree of emulsification and foaming abilities of $1.1R_6MA$-8.8VA increased after cross-linking. However, there was no clear difference between them. The B-O bonds were attached to a $1.1R_6MA$-8.8VA cotelomer with a limited variation of the active surface properties.