3,4-环氧环己基甲基-3,4-环氧环己基甲酸酯
| 3,4-环氧环己基甲基-3,4-环氧环己基甲酸酯 | |
|---|---|
| |
| 识别 | |
| 缩写 | ECC |
| CAS号 | 2386-87-0 
|
| PubChem | 16949 |
| ChemSpider | 16058 |
| SMILES |
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| 性质 | |
| 化学式 | C14H20O4 |
| 摩尔质量 | 252.31 g·mol−1 |
| 外观 | 无色液体[1] |
| 密度 | 1.17 g·cm−3[1] |
| 熔点 | −37 °C（−35 °F；236 K）[1] |
| 溶解性（水） | 13.85 g·l−1（20 °C）[1] |
| 若非注明，所有数据均出自标准状态（25 ℃，100 kPa）下。 | |
3,4-环氧环己基甲基-3,4-环氧环己基甲酸酯（3,4-Epoxycyclohexylmethyl-3',4'-epoxycyclohexane carboxylate，ECC）是一种环脂族环氧树脂，可用于多种工业用途。它通过阳离子聚合反应，使用热致光引发剂形成交联的不溶性热固性聚合物。众所周知，基于环脂族环氧树脂（如 ECC）的配方可通过固化形成具有高耐热性、耐化学性和良好粘合性的热固性塑料。[2]
历史
[编辑]ECC 的均聚是以辐射固化为基础，通过光化学作用形成超强酸，然后进行阳离子聚合，于20世纪70年代首次实现的。[3]
制造
[编辑]ECC 可通过四氢苯甲醛的季先科反应以及随后与过酸的环氧化反应制备。[4]
特性
[编辑]反应性
[编辑]在ECC的均聚过程中，需要添加1.5~3 wt%的引发剂。3 wt%以上的引发剂不会进一步加速反应，但引发剂比例的增加会增加所形成的热固性塑料的脆性。在光聚合之后，通常还需要进行热后固化，才能完全反应。[5]
这种单体的反应活性低于其可能达到的水平，因为所含的酯基会与活性聚合链端发生反应并稳定。因此，它的反应速度明显慢于其他不含酯基的分子。[2][6]ECC的聚合速度也比自由基单体慢得多。因此，研究的目标是找到聚合速度更快但性能相同的阳离子可聚合单体。[2]
交联
[编辑]阳离子交联ECC具有低粘度、优异的电气性能和高可靠性等特点，可用作绝缘体、镀膜、粘合剂或印刷油墨，广泛应用于各种工业领域。[7]然而，均聚ECC极易变脆，要解决这个问题，可以在环氧树脂基体中加入橡胶或硅树脂等弹性体颗粒、加入无机填料[8]，或在聚酯多元醇[9]的作用下通过聚合作用进行塑化。聚酯多元醇通过单体活化机制与聚合物网络共价结合。[10]
参考
[编辑]- ^ 1.0 1.1 1.2 1.3 Record of 3,4-Epoxycyclohexylmethyl-3',4'-epoxycyclohexancarboxylat in the GESTIS Substance Database from the IFA, accessed on 1 January 2015
- ^ 2.0 2.1 2.2 2.3 Sasaki, Hiroshi. Curing properties of cycloaliphatic epoxy derivatives. Progress in Organic Coatings. February 2007, 58 (2–3): 227–230. doi:10.1016/j.porgcoat.2006.09.030.
- ^ Crivello, J. V.; Lam, J. H. W. Dye-sensitized photoinitiated cationic polymerization. Journal of Polymer Science: Polymer Chemistry Edition. October 1978, 16 (10): 2441–2451. Bibcode:1978JPoSA..16.2441C. doi:10.1002/pol.1978.170161004.
- ^ Dillman, Brian; Jessop, Julie L. P. Chain transfer agents in cationic photopolymerization of a bis-cycloaliphatic epoxide monomer: Kinetic and physical property effects. Journal of Polymer Science Part A: Polymer Chemistry. 2013-05-01, 51 (9): 2058–2067. Bibcode:2013JPoSA..51.2058D. doi:10.1002/pola.26595.
- ^ Atsushi Udagawa; Yasuhiko Yamamoto; Yoshio Inoue; Riichirô Chûjô. Dynamic mechanical properties of cycloaliphatic epoxy resins cured by ultra-violet- and heat-initiated cationic polymerizations. Polymer. January 1991, 32 (15): 2779–2784. doi:10.1016/0032-3861(91)90108-U.
- ^ Crivello, James V.; Varlemann, Ulrike. Mechanistic study of the reactivity of 3,4-epoxycyclohexylmethyl 3′,4′-epoxycyclohexancarboxylate in photoinitiated cationic polymerizations. Journal of Polymer Science Part A: Polymer Chemistry. October 1995, 33 (14): 2473–2486. doi:10.1002/pola.1995.080331421.
- ^ Cristina Mas; Ana Mantecón; Angels Serra; Xavier Ramis & Josep Maria Salla. Improved thermosets obtained from cycloaliphatic epoxy resins and γ-butyrolactone with lanthanide triflates as initiators. I. Study of curing by differential scanning calorimetry and Fourier transform infrared. Journal of Polymer Science Part A: Polymer Chemistry. 2005-06-01, 43 (11): 2337–2347. Bibcode:2005JPoSA..43.2337M. doi:10.1002/pola.20711.
- ^ Lützen, Hendrik; Bitomsky, Peter; Rezwan, Kurosch; Hartwig, Andreas. Partially crystalline polyols lead to morphology changes and improved mechanical properties of cationically polymerized epoxy resins. European Polymer Journal. January 2013, 49 (1): 167–176. doi:10.1016/j.eurpolymj.2012.10.015.
- ^ Spyrou, Emmanouil. Radiation initiated cationic polymerization with tailor-made polyesters. Progress in Organic Coatings. November 2001, 43 (1–3): 25–31. doi:10.1016/S0300-9440(01)00240-5.
- ^ Yagci, Yusuf; Schnabel, Wolfram. On the mechanism of photoinitiated cationic polymerization in the presence of polyols. Die Angewandte Makromolekulare Chemie. 1999-09-01, 270 (1): 38–41. doi:10.1002/(SICI)1522-9505(19990901)270:1<38::AID-APMC38>3.0.CO;2-S.
相关
[编辑]- Ellis (编). Polymers : a property database 2nd. Boca Raton, Fla.: CRC. 2007: 150. ISBN 978-0-8493-3940-0.