Study on preparation and properties of degradable epoxy composites containing borate ester bond

doi:10.19936/j.cnki.2096-8000.20220128.014

Abstract

Abstract: The three-dimensional network structure of traditional epoxy resin not only endows it with good properties, but also brings challenges to its reprocessing and recycling. In recent years, the introduction of dynamic covalent bond into thermosetting resin to achieve degradation has been emerging, but it is still an urgent requirement to achieve degradation in a mild and green method. In this paper, phenylboronic acid (PBA) was used to cure bisphenol-A epoxy resin (DGEBA, E44) to form dynamic borate ester bond. The superior heat resistance of cured resin (PBAE) was investigated by Differential Scanning Calorimetry (DSC) and Thermogravimetric analysis (TGA). Glass transition temperature (T_g) and 5% weight loss temperature (T_d5) were 147 ℃ and 267 ℃ respectively, while the mass retention rate at 800 ℃ is higher than 25%. Based on this matrix, recyclable glass fiber-reinforced PBAE composite was prepared, which could achieve green and mild degradation in ethanol aqueous solution (volume ratio=2∶1) at room temperature. PBAE composite exhibited comparable mechanical properties, with bending strength of 499 MPa and interlaminar shear strength of 70 MPa. In addition, PBAE composites could facilely achieve self-healing under heating and pressure conditions.

Key words: phenylboronic acid, epoxy resin, recyclable, green degradation, heat resistance, composites

CLC Number:

TB332

ZHANG Wen-hua, FANG Chao-yu, LI Xin, YOU Li-wen, QI Yi-qing, ZHOU Quan. Study on preparation and properties of degradable epoxy composites containing borate ester bond[J]. COMPOSITES SCIENCE AND ENGINEERING, 2022, 0(1): 91-97.

References

[1] LI Q T, JIANG M J, WU G, et al. Photothermal conversion triggered precisely targeted healing of epoxy resin based on thermoreversible diels-alder network and amino-functionalized carbon nanotubes[J]. ACS Applied Materials &Interfaces, 2017, 9(24): 20797-20807.
[2] MEMON H, WEI Y. Welding and reprocessing of disulfide-containing thermoset epoxy resin exhibiting behavior reminiscent of a thermoplastic[J]. Journal of Applied Polymer Science, 2020, 137(47): 49541.
[3] KLOXIN C J, SCOTT T F, ADZIMA B J, et al. Covalent adaptable networks (CANs): A unique paradigm in crosslinked polymers[J]. Macromolecules, 2010, 43(6): 2643-2653.
[4] LIU H C, ZHANG H, WANG H, et al. Weldable, malleable and programmable epoxy vitrimers with high mechanical properties and water insensitivity[J]. Chemical Engineering Journal, 2019, 368: 61-70.
[5] AAONTARNAL D, CAPELOT M, TOURNILHAC F, et al. Silica-like malleable materials from permanent organic networks[J]. Science, 2011, 334(6058): 965-968.
[6] LIU M, ZHONG J, LI Z, et al. A high stiffness and self-healable polyurethane based on disulfide bonds and hydrogen bonding[J]. European Polymer Journal, 2020, 124: 109475.
[7] AZCUNE I, ODRIOZOLA I. Aromatic disulfide crosslinks in polymer systems: Self-healing, reprocessability, recyclability and more[J]. European Polymer Journal, 2016, 84: 147-160.
[8] LI H, BAI J, SHI Z X, et al. Environmental friendly polymers based on schiff-base reaction with self-healing, remolding and degradable ability[J]. Polymer, 2016, 85: 106-113.
[9] HASHIMOTO T, MEIJI H, URUSHISAKI M, et al. Degradable and chemically recyclable epoxy resins containing acetal linkages: Synthesis, properties, and application for carbon fiber-reinforced plastics[J]. Journal of Polymer Science Part A: Polymer Chemistry, 2012, 50(17): 3674-3681.
[10] YAMAGUCHI A, HASHIMOTO T, KAKICHI Y, et al. Recyclable carbon fiber-reinforced plastics (CFRP) containing degradable acetal linkages: Synthesis, properties, and chemical recycling[J]. Journal of Polymer Science Part A: Polymer Chemistry, 2015, 53(8): 1052-1059.
[11] YANG X, GUO Y, LUO X, et al. Self-healing, recoverable epoxy elastomers and their composites with desirable thermal conductivitiesby incorporating BN fillers via in-situ polymerization[J]. Composites Science and Technology, 2018, 164: 59-64.
[12] ZHANG D D, RUAN Y B, ZHANG B Q, et al. A self-healing PDMS elastomer based on acylhydrazone groups and the role of hydrogen bonds[J]. Polymer, 2017, 120: 189-196.
[13] ZECHEL S, GEITNER R, ABEND M, et al. Intrinsic self-healing polymers with a high E-modulus based on dynamic reversible urea bonds[J]. NPG Asia Materials, 2017, 9(8): 420.
[14] SI H W, ZHOU L, WU Y P, et al. Rapidly reprocessable, degradable epoxy vitrimer and recyclable carbon fiber reinforced thermoset composites relied on high contents of exchangeable aromatic disulfide crosslinks[J]. Composites Part B: Engineering, 2020, 199: 108278.
[15] SHI Q, YU K, DUNN M L, et al. Solvent assisted pressure-free surface welding and reprocessing of malleable epoxy polymers[J]. Macromolecules, 2016, 49(15): 5527-5537.
[16] IVANOV A E, LARSSON H, GALAEV I Y, et al. Synthesis of boronate-containing copolymers of N, N-dimethylacrylamide, their interaction with poly(vinyl alcohol) and rheological behaviour of the gels[J]. Polymer, 2004, 45(8): 2495-2505.
[17] CASH J J, KUBO T, BAPAT A P, et al. Room-temperature self-healing polymers based on dynamic-covalent boronic esters[J]. Macromolecules, 2015, 48(7): 2098-2106.
[18] CHEN Y, TANG Z H, ZHANG X H, et al. Covalently cross-linked elastomers with self-healing and malleable abilities enabled by boronic ester bonds[J]. ACS Applied Materials & Interfaces, 2018, 10(28): 24224-24231.
[19] HEMI N N. Cure and thermal properties of brominated epoxy systems[J]. Journal of Applied Polymer Science, 2010, 33(4): 1173-1185.
[20] 谭怀山, 欧雄燕, 代堂军, 等. 新型含联苯结构环氧树脂的合成与性能[J]. 化工新型材料, 2008, 11: 49-50, 61.
[21] 杨小军, 刘文凤. 玻璃纤维增强复合材料用环氧树脂基体性能研究[J]. 热固性树脂, 2021, 36(1): 27-30.
[22] 孙丽莉, 贾玉玺, 孙胜, 等. 界面强度对纤维复合材料破坏及力学性能的影响[J]. 山东大学学报, 2009, 39(2): 101-103.
[23] 王丽雪, 尹志娟, 刘海鸥. 玻璃纤维增强环氧树脂单向复合材料力学性能分析[J]. 黑龙江工程学院学报, 2009, 23(3): 73-74.
[24] 冯媛媛. 等离子体改性玻璃纤维增强的环氧树脂电气性能研究[D]. 西安: 西安理工大学, 2017.
[25] 郭志昂, 贺辛亥, 张婷, 等. RTM制备玻璃纤维增强环氧树脂复合材料的力学性能分析[J]. 合成纤维, 2020, 49(1): 52-56.