Phase Structure of Hyperbranched Epoxy Resin / Bisphenol A Epoxy Resin Curing System with Different Epoxy Equivalents
-
摘要: 采用光学显微镜研究了不同环氧当量的端羟基超支化环氧树脂(EHBP-n, n=3, 6, 9, 12)/双酚A型环氧树脂(EHBP-n/DGEBA)固化体系的相结构,探讨了EHBP-n/DGEBA固化产物的微观形貌和力学性能的关系。结果表明:随着端羟基超支化环氧树脂质量分数的增加和环氧当量的减小,固化产物的相容性提高。固化微观结构中粒子的尺寸越大,力学性能越好。原位在线观察了9%EHBP-12/DGEBA(EHBP-12的质量分数:9%)的固化过程,提出了均相结构形成的机理。用差示扫描量热法研究了EHBP-12/DGEBA的固化动力学,用扫描电镜背散射电子成像对固化产物的元素分布进行分析,进一步说明EHBP-n与DGEBA具有良好的相容性。Abstract: The phase structures of hyperbranched epoxy resin / bisphenol A epoxy resin (EHBP-n /DGEBA) curing systems were studied by optical microscope. The relationship between the morphologies and mechanical properties of EHBP-n/DGEBA cured products was discussed. The results showed that the compatibility of the cured products was improved with the increase of EHBP-n mass fraction and the decrease of epoxy equivalent. The larger the particle size in the microstructure of the cured products was, the better the mechanical properties were. The curing process of 9%EHBP-12/DGEBA (the mass fraction of EHBP-12: 9%) was observed and the formation mechanism of homogeneous structure was proposed. The in-situ strengthening and toughening mechanism of hyperbranched polymer was confirmed. The curing kinetics of EHBP-n/DGEBA was studied by Differential Scanning Calorimetry (DSC), and the element distribution of the cured product was analyzed by Mapping. It further shows that EHBP-n has good compatibility with DGEBA, and it is a non-phase separation system after curing.
-
Key words:
- hyperbranched epoxy resin /
- epoxy equivalent /
- curing /
- phase structure
-
图 5 9%EHBP-12/DGEBA固化过程的光学显微镜照片: (a) 50 °C,0 min; (b) 50 °C,30 min, (c) 50 °C,60 min;(d) 60 °C,30 min;(e) 70 °C,30 min;(f)80 °C,30 min
Figure 5. Potical microscope images of 9%EHBP-12/DGEBA curing process: (a) 50 °C, 0 min; (b) 50 °C, 30 min; (c) 50 °C, 60 min; (d) 60 °C, 30 min; (e) 70 °C, 30 min; (f)80 °C, 30 min
表 1 不同EHBP-12质量分数的EHBP-12/DGEBA固化物的粒径及分布
Table 1. Particle size and distribution of EHBP-12/DGEBA cured products with different mass fractions of EHBP -12
Sample Particle size/µm Standard deviation PDI DEGBA 35.0 7.10 0.034 3%EHBP-12/DEGBA 38.3 19.99 0.327 6%EHBP-12/DEGBA 24.0 19.21 0.641 9%EHBP-12/DEGBA 42.1 18.99 0.204 12%EHBP-12/DEGBA 37.0 18.04 0.238 15%EHBP-12/DEGBA 22.7 9.81 0.187 表 2 9%EHBP-n/DGEBA固化物的粒径及分布
Table 2. Particle size and distribution of 9%EHBP-n/DGEBA cured products
Sample Particle size/µm Standard deviation PDI 9%EHBP-3/DGEBA 45.0 18.47 0.169 9%EHBP-6/DGEBA 53.1 29.74 0.314 9%EHBP-9/DGEBA 37.5 19.55 0.272 9%EHBP-12/DGEBA 37.0 18.04 0.238 -
[1] 王世崇, 朱雨薇, 吴瑶, 向洪平, 刘晓暄, 彭忠泉, 容敏智, 章明秋. 光固化3 D打印技术及光敏树脂的开发与应用 [J]. 功能高分子学报,2022,35(1):1-17.WANG S C,ZHU Y W, WU Y, XIANG H P, LIU X X, PENG Z Q, RONG M Z, ZHANG M Q. Development and applications of UV-curing 3 D printing and photosensitive resin [J]. Journal of Functional Polymers,2022,35(1):1-17. [2] 杨广杰, 潘李李, 李晓娟, 邓文秀, 刘习奎. 基于可逆动态共价化学的新型可修复、可回收、可加工环氧树脂 [J]. 功能高分子学报,2017,30(2):215-220.YANG G J, PAN L L, LI X J, DEN W X, LIU X K. Recyclable and malleable epoxy resin based on dynamic imine bonding [J]. Journal of Functional Polymers,2017,30(2):215-220. [3] JANUSZEWSKI R, DUTKEWICZ M, NOWICKI M, MARIUSZ S, IRENEUSZ K. Synthesis and properties of epoxy resin modified with novel reactive liquid rubber-based systems [J]. Industrial & Engineering Chemistry Research,2021,60(5):2178-2186. [4] KISHI H, KAZUYOSHI Y, JIN K. Control of nanostructures and fracture toughness of epoxy/acrylic block copolymer blends using in situ manipulation of the epoxy matrix reaction type [J]. Polymer,2019,176(2):89-100. [5] 吴唯, 王佳玮, 张雪薇, 王懿. 二氧化钛纳米管对环氧树脂膨胀阻燃体系的协效阻燃作用 [J]. 功能高分子学报,2018,31(1):88-94.WU W, WANG J W, ZHANG X W, WANG Y. Synergistic effects of titanate nanotubes on intumescent flame retardant epoxy composites [J]. Journal of Functional Polymers,2018,31(1):88-94. [6] ZENG C, LU S, XIAO X, GAO J, PAN L L, HE Z H, YU J H. Enhanced thermal and mechanical properties of epoxy composites by mixing noncovalently functionalized graphene sheets [J]. Polymer Bulletin,2015,72(3):453-472. doi: 10.1007/s00289-014-1280-5 [7] CHEN S, XU Z, ZHANG D. Synthesis and application of epoxy-ended hyperbranched polymers [J]. Chemical Engineering Journal,2018,343(6):283-302. [8] JIANG W, ZHOU Y, YAN D. Hyperbranched polymer vesicles: from self-assembly, characterization, mechanisms, and properties to applications [J]. Chemical Society Reviews,2015,44(12):3874-3889. doi: 10.1039/C4CS00274A [9] 刘兴亮, 罗静, 李小杰, 刘晓亚. 新型双功能性超支化聚合物的制备及表征 [J]. 功能高分子学报,2018,31(2):147-152.LIU X L, LUO J, LI X J, LIU X Y. Preparation and characterization of novel bifunctional hyperbranched polymers [J]. Journal of Functional Polymers,2018,31(2):147-152. [10] 黄鑫, 刘汉超, 樊正, 王豪, 黄光速, 吴锦荣. 超支化聚合物增韧增强的自修复环氧Vitrimer [J]. 高分子学报,2019,50(5):535-542. doi: 10.11777/j.issn1000-3304.2019.19027HUANG X, LIU H C, FAN Z, WANG H, HUANG G S, WU J R. Hyperbranched Polymer Toughened and Reinforced Self-healing Epoxy Vitrimer [J]. Acta Polymerica Sinica,2019,50(5):535-542. doi: 10.11777/j.issn1000-3304.2019.19027 [11] 陈珂龙, 张桐, 崔溢, 王智勇. 超支化聚合物(HBPs)改性环氧树脂的研究进展 [J]. 材料工程,2019,47(7):11-18. doi: 10.11868/j.issn.1001-4381.2018.000395CHEN K L, ZHANG T, CUI Y, WU Z Y. Progress of hyperbranched polymers (HBPs) as modifiers in epoxy resins [J]. Journal of Materials Engineering,2019,47(7):11-18. doi: 10.11868/j.issn.1001-4381.2018.000395 [12] LI J, XIANG Y, ZHENG S. Hyperbranched block copolymer from AB(2) macromonomer: Synthesis and its reaction-induced microphase separation in epoxy thermosets [J]. Journal of Polymer Science Part A: Polymer Chemistry, 2016, 54(3): 368-380. [13] 董慧慧, 朱新远. 两种不同化学组成的超支化聚氨酯改性环氧树脂 [J]. 高分子学报,2017(2):342-350.DONG H H, ZHU X Y. Epoxy resins modified by hyperbranched polyurethanes with different composition [J]. Acta Polymerica Sinica,2017(2):342-350. [14] WANG Y, CHEN S, CHEN X, LU Y F, MIAO M H, ZHANG D H. Controllability of epoxy equivalent weight and performance of hyperbranched epoxy resins [J]. Composites Part B:Engineering,2019,160(1):615-625. [15] CAI W, YUAN Z, WANG Z, GUO Z, ZHANG LI, WANG JUN, LIU W, TANG T. Enhancing the toughness of epoxy resin by using a novel hyperbranched benzoxazine [J]. Reactive and Functional Polymers,2021,164:104920. doi: 10.1016/j.reactfunctpolym.2021.104920 [16] BOOGH L, PETTERSSON B, MANSON J. Dendritic hyperbranched polymers as tougheners for epoxy resins [J]. Polymer,1999,40(9):2249-2261. doi: 10.1016/S0032-3861(98)00464-9 [17] WANG Y, CHEN S, GUO W, MIAO M, ZHANG D. The precise effect of degree of branching of epoxy-ended hyperbranched polymers on intrinsic property and performance [J]. Progress in Organic Coatings,2019,127(2):157-167. [18] ZHANG D, CHEN Y, JIA D. Toughness and reinforcement of diglycidyl ether of bisphenol-A by hyperbranched poly(trimellitic anhydride-butanediol glycol) ester epoxy resin [J]. Polymer Composite,2009,30(7):918-925. doi: 10.1002/pc.20633 -