硅氧烷改性环氧树脂基复合材料层间力学性能与耐热性

曹东风; 陈新昌; 冀运东; 胡海晓; 刘江波; 李书欣

硅氧烷改性环氧树脂基复合材料层间力学性能与耐热性

曹东风^{1, 4, 5},
陈新昌²,
冀运东^{1, 2, ,},
胡海晓^{3, 4, 5},
刘江波²,
李书欣^{1, 3, 4, 5}

1.
武汉理工大学材料复合新技术国家重点实验室, 武汉 430070
2.
武汉理工大学材料科学与工程学院, 武汉 430070
3.
武汉理工大学新材料力学理论与应用湖北省重点实验室, 武汉 430070
4.
先进能源科学与技术广东省实验室佛山分中心(佛山仙湖实验室)
5.
武汉理工大学先进材料制作装备与技术研究院, 武汉 430070

基金项目: 国家自然科学基金(No.52273080)；先进能源科学与技术广东省实验室佛山分中心(佛山仙湖实验室)开放基金 (XHT2020-002)；中央高校基本科研业务费专项资金(2020Ⅲ028GX，2021III015JC，WUT2021IVA068)

详细信息

通讯作者:
冀运东，博士，副教授，硕士生导师，研究方向为复合材料阻燃与残余强度　E-mail:jiyundong@whut.edu.cn

中图分类号: TB332
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- 被引次数: 0
出版历程
- 收稿日期: 2022-11-14
- 修回日期: 2022-12-23
- 录用日期: 2022-12-25
- 网络出版日期: 2023-01-14

Interlaminar mechanical properties and heat resistance of silicone modified epoxy resin composites

Dongfeng CAO^{1, 4, 5},
Xinchang CHEN²,
Yundong JI^{1, 2
, ,},
Haixiao HU^{3, 4, 5},
Jiangbo LIU²,
Shuxin LI^{1, 3, 4, 5}

1.
State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China
2.
School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China
3.
Hubei Key Laboratory of Theory and Application of Advanced Materials Mechanics, Wuhan University of Technology, Wuhan 430070, China
4.
Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory, Foshan 528000, China
5.
Institute of Advanced Materials and Manufacturing Technology, Wuhan University of Technology, Wuhan 430070, China

Funds: National Natural Science Foundation of China(No.52273080)；Open Fund for Advanced Energy Science and Technology Guangdong Provincial Laboratory Foshan Branch (Foshan Xianhu Laboratory) (XHT2020-002)；Special funds for basic scientific research business expenses of central universities(2020Ⅲ028GX,2021III015JC,WUT2021IVA068)

摘要

摘要: 纤维增强环氧树脂基复合材料在航空、航天、船舶以及电子封装等领域扮演着重要的角色，人们希望纤维增强环氧树脂基复合材料在具有更好的力学性能的同时也兼具更佳的环境适用能力(比如耐热和阻燃性能)。聚硅氧烷具有优良的柔韧性和热稳定性、高介电强度、低表面能等特点，在环氧树脂结构中引入具有柔韧性的Si—O键后，可降低固化物内应力从而提高韧性，同时还可以提升体系的热稳定性，聚硅氧烷对环氧树脂的增韧耐热改性成为相关领域的研究热点。本文通过端羟基聚二甲基硅氧烷与环氧树脂(EP)的缩合反应对纤维增强树脂基复合材料的基体进行改性，采用双悬臂梁和短梁剪切等实验对复合材料的层间力学性能进行测量，通过热失重和动态机械热测试对复合材料的耐热性能进行评价。实验结果表明：硅氧烷改性后复合材料的I型临界应变能释放率(断裂韧性)提升了98.1%，层间剪切强度提升13.3%，层间力学性能的强化归因于Si—O键柔性链段、“韧性点”发挥“钉锚”作用以及纤维/基体界面强化的综合作用，其层间破坏模式由纤维基体脱粘转变为基体内聚破坏。硅氧烷改性后复合材料耐热性能也得到了明显提升，最大热失重速率降低了33.1%，800℃最终残余增加了13.5倍。在T_g之前ES-GF的储能模量比EP-GF提高1.3 GPa，在T_g之后ES-GF的储能模量比EP-GF提高近10.8%，硅氧烷增韧改性并未降低环氧树脂的玻璃化转变温度，甚至略有提高。1复合材料层间破坏模型、浇铸体及复合材料的储能模量图Interlaminar failure model of composite, storage modulus of resin and their composites
- 端羟基聚二甲基硅氧烷(HTPDMS) /
- 改性 /
- 环氧树脂基复合材料 /
- 层间性能 /
- 耐热性能
Abstract: The research on improving the interlayer mechanical properties and heat resistance of epoxy resin matrix composites through toughening modification of epoxy resin matrix has important engineering application value. Modified resin (ES) was prepared by condensation reaction of hydroxyl terminated polydimethylsiloxane and epoxy resin, and glass fiber reinforced epoxy resin matrix composite (ES-GF) was prepared by vacuum introduction method. The interlaminar mechanical properties of the composite were measured by double cantilever beam and short beam shear tests. The thermal resistance of the composite was evaluated by thermogravimetry and dynamic mechanical thermal testing. The interlaminar mechanical properties and thermal resistance of the corresponding glass fiber reinforced unmodified epoxy matrix composites (EP-GF) were also tested for comparative analysis. In order to analyze the physical mechanism of strengthening the interlaminar mechanical properties and improving the heat resistance of the composite, the tensile strength, tensile modulus, flexural strength, flexural modulus, tensile elongation at break, pendulum impact strength and microstructure characteristics of the epoxy resin before and after modification were also measured and characterized. The experimental results show that, compared with EP-GF, the release rate of type I critical strain energy (fracture toughness) of ES-GF is increased by 98.1%, and the interlaminar shear strength is increased by 13.3%. The strengthening of interlaminar mechanical properties is attributed to the comprehensive effect of Si—O bond flexible chain segment, "ductile points" playing a "nail anchor" role and improvement of fiber/matrix wettability. The maximum thermal weight loss rate of ES decreased by 33.1%, and the final residue at 800 ℃ increased by 13.5 times. Before T_g, the storage modulus of ES GF is 1.3 GPa higher than that of EP GF, and after T_g, the storage modulus of ES GF is nearly 1.3 GPa higher than that of EP GF, and the glass transition temperature of siloxane modified epoxy resin is slightly increased.
- hydroxyl terminated polydimethylsiloxane (HTPDMS) /
- modification /
- epoxy resin matrix composite /
- interlayer performance /
- heat resistance

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图 1 端羟基聚二甲基硅氧烷改性环氧树脂反应机制

Figure 1. Reaction mechanism of epoxy resin modified by hydroxyl terminated polydimethylsiloxane

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图 2 DCB实验测试图

Figure 2. DCB experimental test diagram

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图 3 EP与ES树脂的断裂延伸率和冲击强度

Figure 3. The tensile strength and elongation at break of EP and ES

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图 4 EP与ES树脂浇铸体的拉伸强度和模量(a)以及弯曲强度和模量(b)

Figure 4. Tensile strength and modulus (a) Flexural strength and modulus (b) of EP and ES resin

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图 5 EP和ES浇铸体拉伸试样断面扫描电镜图

Figure 5. The SEM images of EP (a) and ES (b)

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图 6 EP-GF和ES-GF层间剪切强度

Figure 6. Interlaminar shear strength of EP-GF and ES-GF

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图 7 复合材料短梁剪切测试载荷位移曲线

Figure 7. Load displacement curve of composite short beam shear test

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图 8 EP-GF(a)与ES-GF(b)短梁剪切截面形貌

Figure 8. Cross-sectional morphology of EP-GF(a) and ES-GF composite short beam shear

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图 9 EP-GF和ES-GF的DCB测试的R曲线

Figure 9. R-curves of EP-GF and ES-GF for DCB test

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图 10 EP与玻璃板的润湿角(a)，ES与玻璃板的润湿角(b)

Figure 10. Wetting angle between EP and glass plate (a), and between ES and glass plate (b)

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图 11 EP-GF(a)(b)和ES-GF(c)(d)的断裂面SEM图像

Figure 11. SEM images of fracture surface EP-GF (a)(c) and ES-GF (b)(d) after DCB test

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图 12 ES-GF纤维与树脂间的裂纹扩展示意图

Figure 12. Schematic diagram of crack propagation between fiber and resin of ES-GF

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图 13 EP和ES的TG(a)和DTG(b)曲线

Figure 13. TG (a) and DTG (b) curves of EP and ES

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图 14 EP和ES的DSC曲线

Figure 14. DSC curves of EP and ES resin

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图 15 树脂浇铸体及其复合材料的储能模量(a)、损耗模量(b)和损耗因子tanδ

Figure 15. Storage modulus (a), loss modulus (b) and loss factor of resin casting and its composites tanδ

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表 1 环氧树脂(EP)与端羟基聚二甲基硅氧烷改性环氧树脂(ES)固化配比表(质量比)

Table 1. Epoxy resin (EP) and silicone modified epoxy resin (ES) curing ratio table(Mass ratio)

Name	E51/%	HTPDMS/%	MeHHPA/%	DMP-30/%
EP	100	0	85.68	0.5
ES	80	20	68.54	0.5

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表 2 EP和ES在空气气氛下的热失重数据

Table 2. Thermogravimetric data of EP and ES in air

Atmosphere	Sample	T_−5%/℃	T_−10%/℃	T_max1/℃	T_max2/℃	Char residue in 800℃/wt%
Air	EP	323.0	337.0	369.9	517.3	0.37
Air	ES	299.9	317.9	351.0	507.4	5.38
Notes: T_−5% is onset degradation temperature (temperature at 5.0 wt.% mass loss), T_−10% is the temperature at 10 wt.% mass loss, T_max1 and T_max2 are the maximum decomposition temperature in the first and second stage.

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