有机-无机复合气凝胶的制备及其阻燃性能研究进展

罗伟; 王林生; 陈裕欣; 杨宏宇

doi:10.13801/j.cnki.fhclxb.20210324.002

有机-无机复合气凝胶的制备及其阻燃性能研究进展

doi: 10.13801/j.cnki.fhclxb.20210324.002

重庆大学　材料科学与工程学院，重庆，400045

基金项目: 中央高校基本科研业务费基础与前沿交叉项目(2020CDJQY-A006)；重庆市大学生创新训练项目(S201910611306)

详细信息

通讯作者:
杨宏宇，博士，副教授，博士生导师，研究方向为高分子阻燃材料　E-mail：yhongyu@cqu.edu.cn

中图分类号: TB332
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出版历程
- 收稿日期: 2021-01-21
- 录用日期: 2021-03-18
- 网络出版日期: 2021-03-26
- 刊出日期: 2021-07-15

Research progress on preparation and flame retardant properties of organic-inorganic composite aerogel

College of Materials Science and Engineering, Chongqing University, Chongqing 400045, China

摘要

摘要: 以有机高分子材料为基体，复合无机填料制备的气凝胶复合材料具有超轻、绝热、阻燃等优异特性，可广泛应用在建筑节能保温、电子工业、航空航天等领域。本文报道了有机-无机气凝胶复合材料的制备工艺过程和方法，对比了现有气凝胶材料制备方法的优缺点，并综述了当前研究热点的几种常见气凝胶复合材料：聚乙烯醇类、纤维素类、海藻酸盐类、果胶类有机相复合无机组份气凝胶材料的研究进展。总结了气凝胶复合材料的未来发展方向：亟需在气凝胶材料的机械性能优化方面做出改进，还需提高气凝胶复合材料耐水性能，研究无机填料对不同基体气凝胶阻燃等性能的影响规律，拓展生物质可降解高分子基气凝胶复合材料的种类，实现气凝胶材料的工业化应用。
- 气凝胶复合材料 /
- 有机凝胶 /
- 无机填料 /
- 制备方法 /
- 阻燃性能
Abstract: Aerogel composites made from organic polymer materials and inorganic fillers have excellent properties such as ultralight, heat insulation and flame retardant, which can be widely used in building energy saving and heat preservation, electronics industry, aerospace and other fields. This paper reported the preparation of organic-inorganic aerogel composite materials processes and methods, compared the advantages and disadvantages of the existing aerogel materials preparation methods, and summarizes the current research hot spots of several common aerogel composite materials, including: poly (vinyl alcohol), cellulose, alginate and pectin as organic phase, inorganic components as filler. The future development of aerogel composites is summarized: the mechanical properties and water resistance of aerogel composites need to be improved, the influence of inorganic fillers on the properties of aerogels with different matrixes should be studied, the variety of biomass degradable aerogel composites should be expanded, and the industrial application of aerogel materials needs to be realized.
- aerogel composite material /
- organic gel /
- inorganic filler /
- preparation method /
- flame retardant performance

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图 1 一种聚乙烯醇-纳米粘土气凝胶的制备过程^[27]

Figure 1. Preparation process of a PVA-nanoclay aerogel^[27]

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图 2 不同干燥方法对凝胶形貌的影响^[22]

Figure 2. Effect of different drying methods on gel morphology^[22]

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图 3 哌嗪改性聚磷酸铵对聚乙烯醇/蒙脱土气凝胶总释放热(a)、比模量(d)及微观形貌((b)~(c))的影响^[27]

Figure 3. Effect of PA-APP on THR (a), specific modulus (d) and morphology ((b)-(c)) of PVA/MMT aerogels^[27]

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图 4 新型熔融交联法制备气凝胶^[29]

Figure 4. Aerogels prepared by a new melting crosslinking method

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图 5 机械强度高、阻燃性能好的双交联气凝胶^[30]

Figure 5. Double-cross-link aerogels with high mechanical strength and good flame-retardant properties

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图 6 碳酸氢钠有效地提高了CNF气凝胶的阻燃性能^[39]

Figure 6. SBC greatly improved the flame-retardant property of CNF aerogel^[39]

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图 7 AlOOH颗粒粘附或包裹在有机网络骨架中^[40]

Figure 7. AlOOH particles were adhered or wrapped in the organic network^[40]

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图 8 AlOOH颗粒提高了气凝胶的阻燃性能^[40]

Figure 8. AlOOH particles increased the flame-retardant property of aerogels^[40]

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图 9 纯CNF气凝胶 (a) 和CNF/BTCA/MDPA气凝胶 (b) 垂直燃烧实验前后对比和各气凝胶试样的极限氧指数(LOI) (c) 和热释放速率(HRR) (d)^[43]

Figure 9. Snapshots of the neat CNF aerogel (a) and CNF/BTCA/MDPA aerogel (b) before and after combustion test, limit oxygen index (LOI) values (c) and heat release rate (HRR) curves (d) of aerogel samples^[43]

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图 10 海藻酸钠的分子结构^[46]

Figure 10. Molecular structure of sodium alginate^[46]

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图 11 使用GDL-碳酸钙二元交联剂、采用间接交联法对海藻酸钠进行交联

Figure 11. Alginate was indirectly crosslinked by GDL-SBC agent

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图 12 后交联法制备气凝胶的流程^[54]

Figure 12. Process of preparing aerogel by post-cross-linking method^[54]

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图 13 使用Al(OH)₃、蒙脱土对海藻酸盐气凝胶进行改性^[54]

Figure 13. Alginate aerogel modified by Al(OH)₃ and montmorillonite^[54]

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表 1 不同干燥方法的对比

Table 1. Comparation of different drying methods

Drying methods	Supercritical drying	Freeze-drying	Atmospheric drying
Advantage	Good structure integrity, high porosity	Easy to operate, high safety	Low energy consumption, short production cycle
Shortage	Complex preparation, high risk	Expensive equipment, damaged pore	Poor structure integrity, large pore size

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表 2 不同有机-无机复合气凝胶的关键指标

Table 2. The important parameters of different organic-inorganic aerogels

Sample	Density/ (g·cm⁻³)	Modulus MPa	LOI/%	PHRR/ (kW·m⁻²)	THR/ (MJ·m⁻²)	TTI/s	Residue/ %	λ/ (W·(m·K)⁻¹)	FIGRA/ (W·s⁻¹)
P5C5^[15]	0.086 ± 0.004	11.43 ± 0.13	−	137.1	16.3	5	76.4	−	6.9
P1C9	0.083 ± 0.001	4.92 ± 3.01	−	10.7	0.26	No flame	94.1	−	0.7
HNPA5^[24]	0.081	0.34	−	−	−	−	−	0.044 ± 0.001	−
SNPA5	0.090	1.02	−	−	−	−	−	0.050 ± 0.002	−
5P5C^[26]	0.105	2.3 ± 0.5	−	182	9.0	−	61.9	−	2.0
5P5C2APP	0.115	0.8 ± 0.2	−	115	12.3	−	57.4	−	0.4
P/M/APP^[27]	0.101 ± 0.001	0.91 ± 0.04	24.5	209.6	20.0	3	46.2	−	14.0***
P/M/PA-APP8	0.096 ± 0.002	1.78 ± 0.14	34.0	94.2	11.5	6	51.3	−	4.7***
P5^[29]	0.075 ± 0.001	2.9 ± 0.4	19.5	366.6	22.2	3	1.5	−	18.3
P5 M3	0.076 ± 0.001	8.1 ± 1.1	22.5	227.3	15.2	1	39.6	−	15.1
P5 M3B	0.079 ± 0.001	30.7 ± 2.5	27.6	146.5	11.3	1	42.2	−	9.7
P5 M5^[30]	0.078	13.9 ± 0.5	22.5	190.3	8.7	4	47.3	−	19.0***
P5PA1.5 M5	0.092	41.9 ± 1.8	38.3	83.8	4.9	6	56.0	0.073	0.7***
PVA-HAP-1^[31]	0.112 ± 0.002	3.3 ± 0.5	21.0 ± 0.5	371	14.54	8	−	0.038 ± 0.002	19.1***
PVA-HAP-3	0.109 ± 0.001	6.4 ± 0.7	22.0 ± 0.5	129	3.51	5	−	0.034 ± 0.002	10.8***
P2L2^[32]	0.040 ± 0.001	2.44 ± 0.12	24.5 ± 0.5	130.90	5.27	1	52.7	0.041	8.73***
P2L2F7	0.116 ± 0.002	11.56 ± 0.23	>60.0	57.64	2.94	3	78.3	0.049	3.84***
C0^[42]	0.180 ± 0.005	−	−	280*	13.2**	17	8.9	−	−
C4	0.450 ± 0.005	−	−	22*	1.6**	26	63.4	−	−
A5^[53]	0.047 ± 0.001	0.99 ± 0.06	−	64	13.2	96	3.3	−	2.6
A5C5	0.085 ± 0.001	5.8 ± 0.7	−	32	12.0	No flame	53.3	−	0.7
A5 MH5^[54]	0.069 ± 0.001	4.92 ± 0.75	>60	24.63	1.79	No flame	66	−	−
A5 MH5Ca	0.110 ± 0.001	7.07 ± 1.12	>60	−	−	−	−	0.039	−
A5C5-6^[57]	0.096 ± 0.002	17 ± 3	−	19.3	3.7	192	66.3	−	−
A5C5-8	0.090 ± 0.003	6.0 ± 0.4	−	20.0	4.6	153	58.6	−	−
P5^[60]	0.06 ± <0.01	0.07 ± 0.01	−	−	−	−	−	−	−
P5C5	0.10 ± <0.01	1.4 ± 0.3	−	−	−	−	−	−	−
PE5^[61]	0.050	1.4 ± 0.2	20.3	370.5	7.7	1	2.2	0.034	37.1
PE5PA2	0.068	3.6 ± 0.1	41.5	69.6	1.8	1	34.6	0.038	4.6
PA0.5PC4^[62]	−	4.7	−	35 ± 3	14.8 ± 1	41 ± 2	−	0.035	0.22 ± 0.01
PA2PC4	−	9.2	−	38 ± 3	3.1 ± 0.3	186 ± 5	−	0.038	0.18 ± 0.01
Notes: λ stands for the thermal conductivity. Because of different experimental equipment and methods, the units of some parameters differ. : the PHRR in W/g; : the THR in kJ/g; **: the FIGRA in kW·(m⁻²·s).

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