PEPA阻燃环氧树脂的性能研究

将反应型含磷阻燃剂1-氧代-4-羟甲基-2,6,7-三氧杂-1-磷杂双环[2.2.2]辛烷(PEPA)与环氧树脂(EP)反应制得含磷EP,经固化剂间苯二胺固化后得到阻燃EP.表征了阻燃EP的热稳定性、成炭性和阻燃性能等.结果显示,PEPA的羟基与EP的环氧基团发生反应,使EP环氧当量提高.随着PEPA含量增加,阻燃EP的氧指数逐渐增大,起始分解温度降低,最终质量保持率增大.PEPA的加入对阻燃EP的玻璃化转变温度影响不大.燃烧后形成的炭层表面结构致密,内部多孔.     

DOPO改性氧化石墨烯阻燃环氧树脂研究

采用9,10-二氢-9-氧杂-10-磷杂菲-10氧化合物(DOPO)对氧化石墨烯(GO)进行表面修饰,并制备阻燃环氧树脂(EP)复合材料。通过傅里叶红外光谱(FT-IR)、X射线衍射(XRD)及热失重分析(TGA)对改性氧化石墨烯(DOPO-GO)进行表征,采用锥形量热仪、扫描电子显微镜(SEM)等对EP复合材料的阻燃性能、残炭微观结构等进行研究。结果表明:DOPO成功对GO进行表面修饰,当DOPO-GO添加量为3%时,EP复合材料的残炭率比纯EP提高了1.8%,从而达到一定的阻燃效果。锥形量热仪测试及残炭微观结构观察得出,EP复合材料热释放速率峰值随着DOPO-GO添加量的增加而降低,接枝后的DOPO-GO会生成PO·,可以捕获聚合物燃烧后释放出的活性自由基H·和OH·,达到中断链式反应的效果。同时,加入DOPO-GO后,复合材料燃烧后的炭层致密,起到延缓环氧基体燃烧的作用。     

两种环氧树脂用磷氮阻燃剂的合成与应用研究

将4,4'-二氨基二苯甲烷(DDM)分别与苯甲醛和水杨醛进行缩合反应,所得两种缩合产物分别再与9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)进行加成反应,得到两种新型磷氮阻燃剂A和B,并通过红外吸收光谱(FTIR)、核磁共振(NMR)和质谱(MS)方法证实了产物的结构。结果表明:所得阻燃剂分子可以和DDM一起充当环氧树脂(EP)的固化剂。将阻燃剂A、B分别同DDM加入到EP中,固化后形成的环氧固化物的Tg值和热稳定性有小幅下降,而阻燃性能大幅提高:当环氧固化体系的含磷量为1.0%时,所有环氧固化物垂直燃烧等级均达到UL94 V-0级;当磷含量达到1.5%时,B的环氧固化物的极限氧指数(LOI)达到41.2%。     

含磷阻燃水性聚氨酯乳液的制备及其性能研究

以9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物（DOPO)和顺丁烯二酸酐(MAH)为原料合成含磷单体DOPOMA,将其与二元酸,二元醇进行缩聚反应,得到侧链含磷的端羟基饱和聚酯二元醇,再将其与TDI反应、二羟甲基丁酸和一缩二乙二醇扩链、三乙胺中和得到含磷阻燃水性聚氨酯。采用红外光谱分析、热重分析、极限氧指数（LOI）、扫描电子显微镜（SEM）等测试手段对含磷高聚物的结构、热稳定性、成炭能力等进行了分析。结果表明：随着P含量的增加,LOI和残炭率逐渐增大。     

环氧树脂/含磷有机硅杂化物固化体系的耐热性与阻燃性研究

利用γ(2,3-环氧丙氧基)丙基三甲氧基硅烷与磷酸反应制备了一种含磷有机硅杂化物,并利用红外光谱对这种含磷有机硅杂化物进行了结构表征。将这种含磷有机硅杂化物加入到双酚A环氧树脂/4,4'-二氨基二苯基甲烷体系制备了环氧树脂/含磷有机硅杂化物固化体系,对这种固化物进行了热失重分析,并测试了其玻璃化转变温度(Tg)和极限氧指数。结果表明,该固化物的Tg比纯环氧树脂固化物有所提高,初始分解温度比纯环氧树脂低,而高温残炭率有大幅提高;当含磷有机硅杂化物含量为30份时,固化物的Tg提高9 ℃,极限氧指数到达27.3 %,700 ℃残炭率达到34.1 %,比纯环氧树脂分别提高28 %和77.8 %。     

新型磷-硅改性环氧树脂的制备及阻燃性能研究

采用3-氨丙基三乙氧基硅烷、磷酸三乙酯和双酚A型环氧树脂为原料,两步法合成了一种新型超支化磷-硅改性环氧树脂(P-Si-EP),通过红外分析确认了其结构并对其进行了氧指数测试,结果显示改性后的环氧树脂固化物氧指数显著提高。红外分析和SEM分析表明P-Si-EP燃烧后形成了含磷-硅的炭层并且外部炭层光滑、完整,内部炭层致密、多孔。     

DOPO型无卤阻燃环氧树脂体系的性能研究

采用9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)和DOPO型含磷环氧树脂(DOPO–EP)对双酚A型EP进行阻燃改性,研究了不同磷含量下两种阻燃剂对EP的改性效果。结果表明,随磷含量增加,EP/DOPO与EP/DOPO–EP体系的玻璃化转变温度均降低,但EP/DOPO–EP体系的降幅较小;DOPO与DOPO–EP均能有效地提高EP的阻燃性能,但DOPO–EP的阻燃效果更佳;EP/DOPO–EP体系的综合力学性能高于EP/DOPO体系。当磷质量分数分别为2.5%和1.5%时,EP/DOPO与EP/DOPO–EP体系的垂直燃烧等级均达到UL 94 V–0级,极限氧指数分别为32%和33%。EP/DOPO体系在磷质量分数为2.5%时的残炭率(700℃)为12.27%,较纯EP提高了17.3%,但其拉伸性能、冲击性能和弯曲强度均大幅下降。而EP/DOPO–EP体系在磷质量分数为1.5%时的残炭率(700℃)为20.07%,较纯EP提高了91.9%,其断裂伸长率和弯曲强度分别为2.32%和92.69 MPa,较纯EP分别提高了13.73%和24.27%,拉伸强度和缺口冲击强度分别为35.34 MPa和1.85 kJ/m2,较纯EP仅下降了1.56%和1.07%,综合性能最佳。     

硅磷杂化物/环氧树脂固化物的性能研究

以γ-环氧丙氧基三甲氧基硅烷(KH-560)与磷酸反应合成了一种含磷硅烷偶联剂,将这种含磷硅烷偶联剂与硅溶胶按一定配比进行水解缩聚反应,得到一种硅磷杂化物,将该硅磷杂化物引入到双酚A环氧树脂(E-51),以4,4′-二氨基二苯基甲烷为固化剂,制备了硅磷杂化物/环氧树脂固化物。对该固化物的玻璃化转变温度、热失重、拉伸强度、极限氧指数(LOI)进行了测试。结果表明,该固化物玻璃化转变温度,700℃残炭量以及LOI均比纯环氧树脂固化物高,拉伸强度却下降较少。当硅磷杂化物的添加量占环氧树脂质量的50%时,该固化物的玻璃化转变温度可以达到178℃,极限氧指数可以达到28.2,与纯环氧树脂固化物相比,分别提高了18℃和25%。与纯环氧树脂固化物相比,该硅磷杂化物/环氧树脂固化物具有较好的阻燃性及热稳定性。     

含DOPO-Si环氧树脂的阻燃和力学性能影响机制研究

为抑制环氧树脂燃烧，文章将硅烷偶联剂与9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物（DOPO）进行反应，合成一种含硅、磷的新型阻燃剂（DOPO-Si），将阻燃剂通过共混或者接枝两种方式加入环氧树脂中，以提高环氧树脂的阻燃性。结果表明：以共混方式引入DOPO-Si，当添加5%的DOPO-Si时，复合材料可通过UL-94垂直燃烧的V-0级，极限氧指数（LOI）达到34.8%，拉伸强度可达70.5 MPa，比纯环氧树脂提高了22.6%。以接枝方式引入DOPO-Si，接枝率为5%时，环氧树脂固化物也可达到UL-94垂直燃烧的V-0级，LOI高达35.1%，但力学性能提升幅度不大。共混和接枝改性方式下，新型阻燃剂DOPO-Si均可提升环氧树脂阻燃性能，同时力学性能也有不同程度提升；但是与纯环氧树脂相比玻璃化转变温度均下降，其中共混方式下降的幅度要大于接枝方式，因此在实际应用中可依据实际需求灵活选取。     

含磷杂菲侧基双酚A酚醛树脂的合成与应用

基于酚醛树脂反应,以二磷杂菲丙基双酚A(DDBA)和甲醛为原料,合成了一种含磷杂菲侧基的二磷杂菲丙基双酚A甲醛树脂(PDBA).通过傅里叶变换红外光谱仪、核磁共振氢谱仪和凝胶渗透色谱仪等证明了产物PDBA的结构.将PDBA和DDBA作为反应型阻燃剂用于环氧树脂(EP)阻燃改性,通过极限氧指数仪、垂直燃烧试验箱、锥形量热...     

聚甲基亚膦酸双酚A酯阻燃剂的合成及其应用

以甲基二氯膦和双酚A为单体,通过熔融缩聚合成了聚甲基亚膦酸双酚A酯(PMPBE)。通过傅里叶变换红外光谱(FTIR)、核磁共振谱仪、热失重分析仪(TGA)、差示扫描量热仪(DSC)、垂直燃烧仪、极限氧指数仪及微型量热仪表征了PMPBE及环氧树脂(EP)/PMPBE共混物的结构和性能。结果表明,随着PMPBE添加量的增加,复合材料的极限氧指数逐渐提高,最大放热速率和放热量逐渐降低,EP在700 ℃的残炭率明显提高。当添加20份PMPBE时,EP的极限氧指数从19.0 %提高到27.6 %,达到V-0级,最大放热速率与放热量均下降了27 %;说明该阻燃剂是良好的本征型阻燃剂。     

磷酸三聚氰胺聚丙烯酸盐膨胀型阻燃剂的制备及性能研究

采用三聚氰胺(MEL)、磷酸(PA)等原料,合成了磷酸三聚氰胺(MP),并将其与聚丙烯酸(PAA)反应,制备了磷酸三聚氰胺聚丙烯酸盐(MPPAA)膨胀型阻燃剂(IFR)。通过红外光谱分析(FTIR)、元素分析(SEM-EDAX)等方法对阻燃剂的结构和元素组成进行了表征,并采用氧指数法、垂直燃烧法、拉力试验等手段检测了环氧树脂(EP)/MPPAA复合材料的阻燃、力学性能。结果表明:当原料中—COOH和—NH2的摩尔比为2:1时,MPPAA收率可达到77.7%,其N元素含量约为39.37%;EP/20%MPPAA阻燃复合材料的氧指数为30%,阻燃等级可达到UL94V-0级;另外,由于形成了互穿聚合物网络(IPN),EP/MPPAA复合材料还具有较高的拉伸性能和韧性。     

A multi-element flame retardant for rail transit to improve the flame retardant performance of epoxy resin while reducing smoke density

A P/N/Si structure flame retardant DTBD was successfully synthesized by 3,5-diaminobenzoic acid, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), triphenylsilanol, and benzaldehyde. The chemical structure of DTBD was analyzed by Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectra, which showed that DTBD was successfully synthesized. By analyzing the curing behavior, the addition of DTBD promoted the curing of epoxy resin (EP). According to the limited oxygen index (LOI) and UL-94 vertical combustion tests, it can be shown that the introduction of DTBD makes the epoxy resin have good self-extinguishing properties. Py-GC/MS analysis showed that the phosphorus free radicals and ammonia generated in the gas phase of DTBD could quench and dilute by capturing reactive free radicals and refractory gases. DTBD could improve the tensile and flexural properties of epoxy resin. According to the European flame retardant standard EN45545-2, the Ds of EP-15 and EP-20 obtained HL1 grade. With the increase in DTBD content, the VOF₄ of modified EP also gradually decreased, and both EP-15 and EP-20 obtained HL2 grade.     

DOPO型环氧树脂用阻燃剂的合成与应用研究

以对苯二胺、4-氟苯甲醛、4-硝基苯甲醛、4-甲氧基苯甲醛、9,10-二氢-9-氧-10-磷杂菲-10-氧化物(DOPO)为原料,经两步反应,合成了3种含磷、氮的DOPO型环氧树脂用阻燃剂,通过1HNMR、FTIR对中间体及目标产物结构进行了表征。将合成的阻燃剂按0.00%、5.00%、10.00%、15.00%、20.00%(按环氧树脂质量计算)加入到环氧树脂(EP)中,加入4,4'-二氨基二苯基甲烷(DDM)固化后得到透明的复合材料,并对复合材料的热稳定性和阻燃性能进行了初步评价。结果表明,添加阻燃剂后的固化物初始失重温度高于300℃,可满足高分子材料加工时对热稳定性的要求;随着固化物中磷含量的增加,固化物的阻燃性增大;当固化物中磷质量分数达到1.00%时,所有固化物都可以达到UL94 V-0级,测得其中N,N'-双[1-(4-硝基苯基)-1-(9-氢-9-氧杂-10-磷杂菲-10-氧化物)-甲基]-1,4-苯二胺(BNP-DOPO/DDM/EP)固化物的极限氧指数(LOI)值为37.0,是三组固化物中最高者。     

Synthesis,thermal and mechanical behavior of a silicon/phosphorus containing epoxy resin

A liquid silicon/phosphorus containing flame retardant (DOPO–TVS) was synthesized with 9,10‐dihydro‐9‐oxa‐10‐phosphapheanthrene‐10‐oxid (DOPO) and triethoxyvinylsilane (TVS). Meanwhile, a modified epoxy resin (IPTS–EP) was prepared by grafting isocyanate propyl triethoxysilane (IPTS) to the side chain of bisphenol A epoxy resin (EP) through radical polymerization. Finally, the flame retardant (DOPO–TVS) was incorporated into the modified epoxy resin (IPTS–EP) through sol–gel reaction between the ethyoxyl of the two intermediates to obtain the silicon/phosphorus containing epoxy resin. The molecular structures of DOPO–TVS, IPTS–EP and the final modified epoxy resin were confirmed by FTIR spectra and ¹H‐NMR, ³¹P‐NMR. Thermogravimetric analysis (TGA), differential scanning calorimetry, and limiting oxygen index were conducted to explore the thermal properties and flame retardancy of the synthesized epoxy resin. The thermal behavior and flame retardancy were improved. After heating to 600°C in a tube furnace, the char residue of the modified resin containing 10 wt % DOPO–TVS displayed more stable feature compared to that of pure EP, which was observed both by visual inspection and scanning electron microscope (SEM). Moreover, the mechanical performance testing results exhibited the modified epoxy resins possessed elevated tensile properties and fracture toughness which is supported by SEM observation of the tensile fracture section. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42788.     

Synthesis of a novel cross‐linked organophosphorus‐nitrogen containing polymer and its application in flame retardant epoxy resins

A novel cross‐linked organophosphorus–nitrogen polymetric flame retardant additive poly(urea tetramethylene phosphonium sulfate) defined as PUTMPS was synthesized by the condensation polymerization between urea and tetrahydroxymethyl phosphonium sulfate. Its chemical structure was well characterized by Fourier transform infrared (FTIR) spectroscopy, ¹³C and ³¹P solid‐state nuclear magnetic resonance. The synthesized PUTMPS and curing agent m‐phenylenediamine were blended into epoxy resins to prepare flame retardant epoxy resin thermosets. The effects of PUTMPS on fire retardancy and thermal degradation behavior of EP/PUTMPS thermosets were investigated by limiting oxygen index (LOI), vertical burning test (UL‐94), cone calorimeter measurement, and thermalgravimetric analysis (TGA) tests. The surface morphologies and chemical compositions of char residues for cured epoxy resins were investigated by scanning electron microscopy and X‐ray photoelectron spectroscopy (XPS), respectively. Water resistant properties of epoxy resin thermosets were evaluated by putting the samples into distilled water at 70°C for 168 h. The results demonstrated that the EP/12 wt% PUTMPS thermosets successfully passed UL‐94 V‐0 flammability rating and the LOI value reached 31.3%. The TGA results indicated that the incorporation of PUTMPS promoted epoxy resin matrix decomposed and char forming ahead of time, which led to a higher char yield and thermal stability for epoxy resin thermosets at high temperature. The morphological structures and analysis of XPS for the char residues of the epoxy resin thermosets shown that PUTMPS benefited to the formation of a sufficient, more compact, and homogeneous char layer with rich flame retardant elements on the materials surface during burning, which prevented the heat transmission and diffusion, limited the production of combustible gases, inhibited the emission of smoke, and then led to the reduction of the heat release rate and smoke produce rate. After water resistance tests, EP/12 wt% PUTMPS thermosets still remained excellent flame retardancy. Copyright © 2015 John Wiley & Sons, Ltd.     

Performance comparison of epoxy resins modified with diphenylphosphine oxide and DOPO

By curing the reaction mixture of diphenylphosphine oxide (DPO) and diglycidyl ether of bisphenol A with 4,4′‐diaminodiphenylsulfone, flame‐retardant epoxy resins (EP/DPO) were prepared. Flame‐retardant epoxy resins modified with 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO) were similarly prepared (denoted as EP/DOPO). The limiting oxygen index value of pure epoxy resin, EP/DPO–P‐0.9 (with a phosphorus content of 0.9 wt%), and EP/DOPO–P‐0.9 are 23.0, 30.5, and 29.4%, respectively. EP/DPO–P‐0.9 reached a UL‐94 vertical burning test V‐0 rating, while EP/DOPO–P‐0.9 failed. The results of the cone calorimetry test, thermo‐oxidative degradation behavior study, and pyrolysis‐gas chromatography/mass spectrometry analysis indicated that both flame retardants mainly act through the gas‐phase activity mechanism. Together, the results of this study suggest that EP/DPO are high performance resins with good thermal stability, high glass transition temperature, and low water absorptivity for practical applications.     

Effect of 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide on liquid oxygen compatibility of bisphenol a epoxy resin

In this study, bisphenol A epoxy resin (DGEBA) was chemically modified by 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO), and the molecular structure of the modified epoxy resin was characterized by Fourier transform infrared spectra. The effects of DOPO on liquid oxygen compatibility of DGEBA were calculated using mechanical impact method. The results indicated that epoxy resin (EP‐P1)/4,4‐diaminobisphenol sulfone (DDS) was compatible with liquid oxygen. When compared with EP/DDS, differential scanning calorimetry and thermogravimetry analyses showed that EP‐P1/DDS and EP‐P2/DDS had much higher glass transition temperatures and char yield. X‐ray photoelectron spectroscopic analysis suggested that phosphorus atoms on the surface of EP‐P1/DDS and EP‐P2/DDS could act in the solid phase to restrain the incompatible reaction, which was in accordance with the flame‐retardant mechanism of phosphorus‐containing compounds. The compatibility mechanism of EP‐P1/DDS was further proposed. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40848.     

高耐热透明阻燃环氧树脂固化体系研究

在以双酚A/四溴双酚A混合环氧树脂(EP)与甲基六氢邻苯二甲酸酐(MeHHPA)构成的胶料基础上,通过加入氯桥酸酐,制备出了具有良好耐热性和阻燃性的透明EP固化物。结果表明:与未加入氯桥酸酐体系相比,当w(氯桥酸酐)=20%(相对于固化剂质量而言)时,EP固化物的总燃烧时间由21 s降至2 s,而氧指数由31%增至37%,玻璃化转变温度(Tg)从123℃提高到148℃,负荷热变形温度(HDT)从108℃增加到129℃。