環氧值
外觀
環氧值源於環氧當量重量(Epoxy equivalent weight,EEW)或每環氧化物重量(Weight Per Epoxide,WPE),是環氧樹脂、環氧活性稀釋劑或縮水甘油醚中環氧含量的量度,是一個重要參數,通過它可以確定環氧體系與固化劑的正確混合比例。[1][2]通常首先通過滴定法測量環氧當量重量。標準測試方法是ASTM D1652,但美國某些州對該方法進行了修改。[3]EEW的定義是:產生1摩爾環氧基團所需的環氧樹脂克數。[4]環氧值定義為每100克樹脂中環氧基團的摩爾數。[5]
計算示例
[編輯]聚氧丙烯二縮水甘油醚是一種活性稀釋劑,商品名為Diluent F,其平均分子量為1000,官能度為 2,因此環氧值為1000/2 = 500。環氧值的定義是每100克樹脂中環氧基的摩爾數。因此,以摩爾質量為382、每摩爾樹脂含有2摩爾環氧基團的環氧樹脂為例,EEW = 382/2 = 191,環氧值的計算公式如下:100/191= 0.53(即樹脂的環氧值為 0.53)。[6]
測試技術
[編輯]有一些方法使用不使用傳統滴定技術的儀器來確定環氧化物當量重量。[7]
相關測試方法
[編輯]參考
[編輯]- ^ Howarth, G.A. 5. Karsa, D.R; Davies, W.D (編). Waterborne Maintenance Systems for Concrete and Metal Structures 165. Cambridge, U.K: The Royal Society of Chemistry. 1995. ISBN 0-85404-740-9.
- ^ How do you know how much hardener to mix with how much resin?:Ask the Doctor. www.mereco.com. [2021-08-01]. (原始內容存檔於2022-09-13).
- ^ Determining Epoxide Equivalent and Amine Value of Resins (PDF). Texas.gov. [2024-05-19]. (原始內容存檔 (PDF)於2024-05-19).
- ^ Spyrou, Emmanouil. Powder coatings chemistry and technology. Hanover. 2012: 129. ISBN 978-3-86630-884-8. OCLC 828194496.
- ^ Howarth, GA. Master of Science thesis "The synthesis of a legislation compliant corrosion protection paint system, based on waterborne epoxy, urethane and oxazolidine technology". April 1997 Imperial College London Chapter 2.1.1 page 32
- ^ Müller, Bodo. Coatings formulation : an international textbook. Urlich Poth. Hannover: Vincentz. 2006: 111. ISBN 3-87870-177-2. OCLC 76886114.
- ^ MONIZ, W. B.; PORANSKI, C. F., Epoxide Equivalent Weight Determination by Carbon-13 Nuclear Magnetic Resonance, Epoxy Resin Chemistry, ACS Symposium Series 114 (AMERICAN CHEMICAL SOCIETY), 1979-12-03, 114: 83–90 [2022-03-23], ISBN 978-0-8412-0525-3, doi:10.1021/bk-1979-0114.ch007
相關
[編輯]- Amines | Introduction to Chemistry. courses.lumenlearning.com. [2021-07-22]. (原始內容存檔於2022-03-25).
- Epoxy resin technology.. Paul F. Bruins, Polytechnic Institute of Brooklyn. New York: Interscience Publishers. 1968. ISBN 0-470-11390-1. OCLC 182890.
- Flick, Ernest W. Epoxy resins, curing agents, compounds, and modifiers : an industrial guide. Park Ridge, NJ. 1993. ISBN 978-0-8155-1708-5. OCLC 915134542.
- Lee, Henry. Handbook of epoxy resins. Kris Neville [2nd, expanded work]. New York: McGraw-Hill. 1967. ISBN 0-07-036997-6. OCLC 311631322.