Preparation of chitosan/ZIF⁃67 hybrid and its effect on flame retardancy and smoke suppression of epoxy resins

doi:10.19491/j.issn.1001-9278.2022.12.005

Abstract

Abstract:

To improve the flame retardancy and smoke suppression performance of epoxy resins （EP）， ZIF⁃67 was loaded on the surface of chitosan （CS） using a co⁃precipitation method. The structure and morphology of the resultant hybrid were analyzed by Fourier⁃transform infrared spectroscopy， X⁃ray diffraction， and scanning electron microscopy. The results indicated that the CS/ZIF⁃67 hybrid was successfully prepared. The effect of different proportions of CS/ZIF⁃67 hybrid on the flame retardant and smoke suppression properties of EP was studied. The results indicated that the addition of CS/ZIF⁃67 hybrid improved the UL 94 grade and LOI value of EP composites and reduced the heat release rate and smoke release rate of EP⁃based composites， The addition of CS/ZIF⁃67 hybrid effectively improved the flame retardant and smoke suppression performance of EP. The SEM and Raman spectroscopy analysis for the residual char after the combustion of EP⁃based composites indicated that the addition of CS/ZIF⁃67 hybrid improved the graphitization degree of the residual char， and a denser carbon layer was formed during the combustion of EP， thus generating flame retardant and smoke suppression effects.

Key words: epoxy resin, chitosan, ZIF?67, flame retardant, smoke suppression

CLC Number:

TQ 323.5

DING Ding, XU Wenzong, YAN Hongyi. Preparation of chitosan/ZIF⁃67 hybrid and its effect on flame retardancy and smoke suppression of epoxy resins[J]. China Plastics, 2022, 36(12): 31-37.

Figures/Tables 11

样品编号	EP/%	DDM/%	CS/%	ZIF⁃67/%	CS⁃ZIF⁃67/%
EP0	78.0	22.0	0	0	0
EP1	75.7	21.3	3	0	0
EP2	77.2	21.8	0	0	1
EP3	75.7	21.3	0	0	3
EP4	74.2	20.8	0	0	5
EP5	75.7	21.3	2.4	0.6	0

Tab.1. Formula of EP and EP composites

Fig.1. FTIR of CS， ZIF⁃67 and CS⁃ZIF⁃67

Fig.2. XRD of CS， ZIF⁃67 and CS⁃ZIF⁃67

Fig.3. SEM of （a） and （b） CS，（c）ZIF⁃67 and （d） CS⁃ZIF⁃67

Fig.4. TGA curves of CS， ZIF⁃67 and CS⁃ZIF⁃67

样品	LOI/%	ΔLOI/%	UL 94	熔滴
EP0	21.3±0.2	-	NR	否
EP1	24.5±0.3	3.2	NR	否
EP2	24.3±0.3	3.0	V⁃2	否
EP3	26.5±0.2	5.2	V⁃1	否
EP4	27.6±0.2	6.3	V⁃1	否
EP5	25.4±0.3	4.1	V⁃2	否

Tab.2. LOI and UL 94 values of EP and EP composites

样品

pHRR/

kW·m^-2

THR/

MJ·m^-2

CY₃₅₀/

pSPR/

m²·s^-1

TSP/

m²

pCOP/

10⁴g·s^-1

Tab.3. Data from combustion tests of EP and EP composites

Fig.5. HRR （a）， THR （b） and char yield （c） curves of EP and EP composites

Fig.6. SPR （a）， TSP （b） and COP （c） curves of EP and EP composites

Fig.7. Digital photos and SEM of char residue of EP0， EP1 and EP4

Fig.8. Laman spectra of residual char of EP0 and EP4

References 14

1	Wang X， Hu Y， Song L， et al. Flame retardancy and thermal degradation mechanism of epoxy resin composites based on a DOPO substituted organophosphorus oligomer［J］. Polymer， 2010， 51（11）： 2 435⁃2 445.
2	Kong Q H， Wu T， Zhang J H， et al. Simultaneously improving flame retardancy and dynamic mechanical properties of epoxy resin nanocomposites through layered copper phenylphosphate［J］. Composites Science and Technology， 2018， 154： 136⁃144.
3	He X D， Zhang W C， Yang R J. The characterization of DOPO/MMT nanocompound and its effect on flame retardancy of epoxy resin［J］. Composites Part A： Applied Science and Manufacturing， 2017， 98： 124⁃135.
4	徐伟华，郑宇，沈向阳，等.不同POSS对磷⁃硅协同阻燃环氧树脂性能的影响［J］.中国塑料，2022，36（04）：115⁃120.
	XU W H， ZHENG Y， SHENG X Y， et al. Effects of different POSS on properties of phosphorus silicon synergistic flame retardant epoxy resin［J］.China Plastics，2022，36（04）：115⁃120.
5	杨柳涛，刘莹，伍玉娇，等. 三聚氰胺基阻燃剂在环氧树脂中的应用进展［J］. 中国塑料，2016，30（3）：10⁃15.
	YANG L T， LIU Y， WU Y J， et al. Research progress of melamine based flame retardants in epoxy resin［J］.China Plastics，2016，30（3）：10⁃15.
6	Luo X L， Shen J Y， Ma Y N， et al. Robust， sustainable cellulose composite aerogels with outstanding flame retardancy and thermal insulation［J］. Carbohydrate Polymers， 2020， 230： 115623.
7	Baishya P， Maji T K. Studies on the physicochemical properties of modified starch⁃based wood nanocomposites［J］. Starch⁃Strke， 2016， 68： 249⁃257.
8	Luda M P， Zanetti M. Cyclodextrins and cyclodextrin derivatives as green char promoters in flame retardants formulations for polymeric materials. a review［J］. Polymers， 2019， 11（4）： 1⁃29.
9	Liu X D， Gu X Y， Sun J， et al. Preparation and characterization of chitosan derivatives and their application as flame retardants in thermoplastic polyurethane［J］. Carbohydrate Polymers， 2017， 167： 356⁃363.
10	Chen R， Luo Z J， Yu X J， et al. Synthesis of chitosan⁃based flame retardant and its fire resistance in epoxy resin［J］. Carbohydrate Polymers， 2020， 245： 116530.
11	Antonio N D， Rocha J V， Ting V P， et al. Flexible ZIFs： probing guest⁃induced flexibility with CO₂， N₂ and Ar adsorption［J］. Journal of Chemical Technology& Biotechnology， 2019， 94： 3 787⁃3 792.
12	Wang B， Zhou K Q， Jiang S， et al. The application of transition metal molybdates （AMoO₄， A=Co， Ni， Cu） as additives in acrylonitrile⁃butadiene⁃styrene with improved flame retardant and smoke suppression properties［J］. Polymers for Advanced Technologies， 2015， 25（12）： 1 419⁃1 425.
13	Ma S C， Hou Y B， Xiao Y L， et al. Metal⁃organic framework@polyaniline nanoarchitecture for improved fire safety and mechanical performance of epoxy resin［J］. Materials Chemistry and Physics， 2020， 247： 122875.
14	Xu W Z， Yan H Y， Wang G S， et al. A silica⁃coated metal⁃organic framework/graphite⁃carbon nitride hybrid for improved fire safety of epoxy resins［J］. Materials Chemistry and Physics， 2021， 258： 123810.

[1]	CHEN Shuhua, REN Zimeng, SUN Tingting. Preparation and properties of chitosan/chitosan⁃grafted⁃graphene oxide composite aerogels [J]. China Plastics, 2022, 36(9): 32-37.
[2]	YANG Jin, CHEN Pengran, GAO Peixin. Preparation and flame-retardant mechanism of epoxy foams synergistically modified with DIDOPO and POSS/EG [J]. China Plastics, 2022, 36(9): 38-45.
[3]	SONG Dejian, YU Peng, PENG Jinsong, XU Miaojun. Preparation of flame retardant EVA hot melt adhesive and its application in repairing cables [J]. China Plastics, 2022, 36(9): 53-56.
[4]	MENG Xin, WANG Xiaolong, GONG Weiguang, JIN Yi. Preparation of three⁃sources⁃in⁃one shell⁃core structural flame retardants and its application in poly（lactic acid） [J]. China Plastics, 2022, 36(9): 96-104.
[5]	LI Yafei, SUN Xiaojie, REN Yueqing, ZHANG Yinling. Preparation and properties of flame⁃retarded anti⁃static polyolefin plates [J]. China Plastics, 2022, 36(8): 23-27.
[6]	CHEN Baiquan, ZHENG Youming, TIAN Jibo, XHANG Lei, WANG Jinsong, LIN Xiajie, DUAN Yapeng. Preparation and properties of polyamide flame⁃retardant composite reinforced with high content of glass fiber [J]. China Plastics, 2022, 36(8): 42-48.
[7]	WU Wei, HU Huanbo, SHEN Hui, ZHAO Tianyu. Dual⁃synergistic effect of 4A zeolite and Ca⁃Mg⁃Al hydrotalcite on intumescent flame retardant PP and its mechanism [J]. China Plastics, 2022, 36(7): 1-7.
[8]	WEI Simiao, SHAO Lushan, XU Zhun, LIU Yanting, ZHAO Siheng, XU Bo. Flame⁃retardant performance of PA6 modified with hypophosphite/siloxane bi⁃functional compound and diethyl aluminum hypophosphite compound [J]. China Plastics, 2022, 36(7): 129-135.
[9]	TAN Liqin, LIU Weiqu, LIANG Liyan, WANG Shuo, FENG Zhiqiang, LIN Jiaming. Preparation and performance of epoxy resin modified with mercaptan polysiloxane [J]. China Plastics, 2022, 36(7): 21-29.
[10]	XU Jie, ZHONG Jinfu, TONG Xiaoqian, LI Guangfu, FU Dongliang, LI Chengcheng. Preparation and performance of carboxyl⁃terminated tannic acid/gallic acid⁃based epoxy composite [J]. China Plastics, 2022, 36(7): 44-50.
[11]	YANG Xiaochun, YU Jing, ZHANG Qing. Effects of chitosan on thermal stability of PVC [J]. China Plastics, 2022, 36(7): 68-73.
[12]	ZHOU Shuyi, ZHU Min, LIU Yiying, CAO Shuhui, CAI Qixuan, NIE Hui, ZHANG Yuxia, ZHOU Hongfu. Research progress in polymer⁃based hemostatic materials [J]. China Plastics, 2022, 36(7): 74-84.
[13]	CHEN Ke, LIU Mingfei, ZHAO Biao, PAN Kai. Research progress in flame retardancy and ablation resistance of silicone⁃modified polymeric materials [J]. China Plastics, 2022, 36(6): 149-154.
[14]	YI Huijun, TANG Ming, ZHANG Qingyi, BAI Yinna. Study on properties of light⁃cured resin products for 3D printing [J]. China Plastics, 2022, 36(5): 43-46.
[15]	LI Fujie, QI Bin, XU Huating, WANG Limei. Preparation and properties of chitosan/polyvinyl alcohol/snail mucus composite films [J]. China Plastics, 2022, 36(5): 53-61.