膨胀型无卤阻燃环氧树脂的制备及性能

采用新型磷系阻燃剂(FR)与聚磷酸铵组成的膨胀型阻燃剂(IFR)制备了膨胀型无卤阻燃环氧树脂(EP)材料.通过氧指数、热失重和扫描电镜等研究IFR对环氧树脂的阻燃性能、热降解行为及微观结构的影响.结果表明:加入IFR使材料的阻燃性能明显提高,IFR/EP的氧指数达到37.6%.600℃时IFR/EP的残炭量较纯EP从21.24%增至43.08%.扫描电镜观察发现.经IFR阻燃的EP在燃烧时形成了由封闭孔洞构成的均匀闭孔结构炭层,表明IFR对EP材料具有良好的膨胀阻燃效果.     

含硫磷三分子缩合物阻燃聚乙烯复合材料的热降解动力学研究

采用不同升温速率研究含硫磷三分子缩合物无卤阻燃剂(S-TRIMER)阻燃LLDPE体系在氮气氛围中的热降解动力学.并采用两种不同的动力学分析方法(即Kissinger方法和Flynn-Wall-Ozawa方法)对阻燃LLDPE体系的热降解动力学进行了理论分析.其中,Kissinger方法计算出的活化能顺序为LLDPE＜LLDPE/S-TRIMER＜LLDPE/IFR,而Flynn-Wall-Ozawa方法计算出的活化能在热降解的初始阶段阻燃LLDPE的活化能小于LLDPE,但是当转化率α≥0.3时阻燃LLDPE的活化能大于LLDPE,这说明对于该体系第一热解阶段(即0.05≤α≤0.2)主要是阻燃剂发生分解,分解的阻燃剂抑制了基体LLDPE的进一步降解,使体系的活化能提高.上述两种方法计算的结果接近,阻燃聚乙烯的活化能比未阻燃聚乙烯的高,说明了阻燃聚乙烯有着更好的热稳定性,即阻燃剂S-TRIMER能提高LLDPE基体的热降解性能.     

有机硅阻燃环氧树脂体系的热降解动力学分析

为获得有机硅阻燃环氧树脂体系在热降解过程中的动力学数据,并阐明有机硅阻燃剂的作用机理,使用Change法对该体系的热降解动力学进行分析,结果发现该体系的热降解过程为一级反应。相比于空白体系,阻燃体系的平均热降解活化能更高,成炭性能更好,这表明有机硅阻燃剂在材料热降解过程中起到了较好的稳定作用,最终达到了提高阻燃体系成炭率和阻燃性的目的。     

型阻燃环氧树脂复合材料的阻燃及燃烧特性

合成新型树状单分子磷-溴阻燃剂1,3,5-三(5,5-二溴甲基-1,3-二氧杂已内磷酰氧基)苯(FR),制备阻燃环氧树脂(EP)复合材料,利用极限氧指数(LOI)、垂直燃烧(UL-94)、锥形量热(CONE)等方法研究FR对环氧树脂的阻燃性能及燃烧特性的影响.结果表明:当FR添加量为30%时,阻燃EP的LOI达到29.4%,垂直燃烧通过V-O级,其av-HRR,av-EHC,av-SEA及av-MLR较未阻燃EP分别降低87.5%、92.8%、90.8%和58.5%,呈现出良好地阻燃效果和抑烟性能;扫描电子显微镜(SEM)观测发现:阻燃EP燃烧后形成了均匀闭孔炭层.     

耐水阻燃透明型环氧树脂的制备及其应用研究

以二苯基次磷酰氯和哌嗪为原料,成功合成了疏水性阻燃剂哌嗪-1,4-二烷基双(二苯基氧化膦)(PPDO),并将其添加到环氧树脂(EP)中,制备了阻燃EP复合材料.通过垂直燃烧、氧指数、热失重分析、锥形量热分析和力学性能测试对EP复合材料的阻燃性能、热分解行为、燃烧行为和力学性能进行了详细研究.结果表明,阻燃剂含量为17％...     

二茂铁对DOPO/环氧树脂体系燃烧性能及固化反应动力学的影响

为研究二茂铁对磷杂菲(DOPO)/环氧树脂(EP)体系燃烧性能及固化反应动力学的影响,将不同比例的二茂铁与DOPO/EP体系复配制备了阻燃EP复合材料,通过氧指数(LOI)测试、UL94垂直燃烧测试、烟密度测试和热重分析研究了阻燃EP复合材料的燃烧性能和热氧稳定性,并通过非等温DSC法研究了二茂铁对DOPO/EP体系固化反应动力学的影响。结果表明,二茂铁和DOPO在阻燃EP复合材料中表现出明显的阻燃协效作用,添加了二茂铁的阻燃EP复合材料的LOI最高可达34.8%,烟密度等级(SDR)最低降至71.43。热重分析表明,二茂铁会降低阻燃EP复合材料的热氧稳定性,但是可以显著增加热解残炭量。固化反应动力学研究结果表明,二茂铁的添加使阻燃EP体系固化反应的活化能E_a和指前因子A均减小。研究工作可以为高性能阻燃EP复合材料的开发提供参考。     

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.     

无卤阻燃PF/EP/GF布复合材料的固化性能和阻燃性能

采用环氧树脂(EP)作固化剂,2,4,6-三(二甲胺基甲基)-苯酚(DMP30)作固化促进剂改善酚醛树脂(PF)的固化性能,以氢氧化铝和有机磷阻燃剂协同改性其阻燃性能,将其涂覆于玻璃纤维(GF)布上,压制成无卤阻燃PF/EP/GF布复合材料.用傅立叶变换红外光谱(FTIR)仪和差示扫描量热(DSC)仪对无卤阻燃PF/EP/GF布复合材料的固化反应机理、固化反应动力学进行了分析研究,并测试了该复合材料的阻燃性能.结果表明,无卤阻燃PF/EP/GF布复合材料的固化反应表观活化能Ea=75.7 kJ/mol、反应级数n=0.91,起始固化温度、固化峰顶温度、固化终止温度分别为108.6、133.2、152.9℃;当氢氧化铝质量分数为14%、DMP30质量分数为1%、有机磷阻燃剂质量分数为4.8%时,无卤阻燃PF/EP/GF布复合材料的固化性能、阻燃性能均达到较佳状态.     

不变动力学参数法研究热固性阻燃聚乳酸的热降解动力学

以9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)为阻燃剂,制备了热固性阻燃聚乳酸材料,利用热重分析仪(TGA)获得了不同升温速率下热固性阻燃聚乳酸材料热降解过程的热重曲线,并应用不变动力学参数法建立其热降解动力学模型,评估了18个动力学函数对材料热降解过程的贡献率。研究发现:随着热降解转化率(α)的增加,材料的热降解活化能呈缓慢上升趋势;阻燃剂DOPO的加入提高了热固性聚乳酸材料的热稳定性,并改变了各个动力学函数对热降解的贡献率,但没有改变聚乳酸热降解的核心机制。     

聚磷酸铵膨胀型阻燃剂在聚合物中应用的研究进展

综述了聚磷酸铵膨胀型阻燃剂的阻燃机理,介绍了该阻燃剂对聚丙烯(PP)、聚乙烯(PE)、ABS树脂、环氧树脂(EP)、尼龙(PA)、聚甲醛(POM)等材料燃烧性能的影响,并对该阻燃剂在阻燃方面的发展趋势、应用前景作了展望.     

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.     

聚苯基甲氧基硅氧烷改性环氧树脂的阻燃性能研究

采用氧指数(LOI),UL-94,热失重(TGA)等手段考察了聚苯基甲氧基硅氧烷(PPMS)改性对环氧树脂(E-20)固化体系阻燃性能的影响.相比未改性环氧体系,当m(E-20)∶m(PPMS)=73∶时,改性环氧体系的LOI由纯E-20环氧树脂的17.5%上升到21.5%;水平火蔓延速率由36.23 mm/min降低到26.60 mm/min;质量损失为5%时的热分解温度由134.7℃上升到163.0℃,750℃时残炭量由0.21%增加到25.79%.此外,还通过红外光谱对燃烧后的残炭结构进行了分析,探讨了相关阻燃机理.     

木质素与含磷阻燃剂对环氧树脂固化物阻燃性能的影响

利用不同质量比的木质素、苯酐（PA）、环氧树脂（EP）、2-（二苯基磷酰基）琥珀酸（DPPOSA）共固化制备出一系列环氧树脂固化物,采用极限氧指数测试、UL-94垂直燃烧评级测试、锥形量热仪热释放速率和总热释放量测试、空气条件下的热重分析测试和扫描电镜对环氧固化物进行测试和分析。当EP为90.0%、PA为6.5%、DPPOSA为2.0%、木质素为1.5%时制备的环氧固化物（P-12）的热稳定性能和阻燃性能得到了明显的改善。阻燃性能测试表明：其极限氧指数（LOI）达到34.6%,垂直燃烧测试通过UL-94的V-0级,热释放速率和热释放总量也有效降低;热降解测试结果表明：DPPOSA和木质素的加入可以使材料的降解时间提前,成炭能力增强;扫描电镜结果显示：添加DPPOSA和木质素的环氧固化物燃烧后形成连续、均一、紧密的炭层,进一步证明DPPOSA和木质素的加入使环氧固化物的成炭能力得到增强。     

Simultaneously Improving the Thermal,Flame‐Retardant and Mechanical Properties of Epoxy Resins Modified by a Novel Multi‐Element Synergistic Flame Retardant

To obtain epoxy resins with satisfactory thermal, flame retardant, and mechanical properties, a novel multi‐element synergistic flame retardant (PPVSZ) is synthesized through the reaction between P? H of 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO) and C?C of polysilazane (PVSZ) and utilized as a multi‐element synergistic flame retardant for epoxy resins. The flame retardant mechanism is explored by XPS and SEM, confirming that the excellent flame‐retardance efficiency owes itself to an optimal flame retardant way which jointly exerts the flame‐retardant effects in the gaseous and condensed phase. The thermal properties deduced from DSC, TGA, and DMA, indicate the glass transition temperature, maximum weight loss rate, and char yields at 700 °C for EP‐2 increase by about 5.0 °C, 8.4 °C and 8.8%, respectively. Furthermore, mechanical properties such as impact strength, tensile strength, and flexural strength are also increased by 45.38%, 14.16%, and 17.43%, respectively, which show that the incorporation of PPVSZ does not deteriorate the mechanical properties of modified resin. All the results demonstrate that epoxy resins modified by PPVSZ not only have good effect on the flame retardance, but also have good improvement on thermal and mechanical properties, indicating the potential for applications in many fields requiring fire safety.     

Reactive organophosphorus flame retardant for transparency,low-flammability,and mechanical reinforcement epoxy resin

To maintain transparency and improve flame retardancy and mechanical properties of epoxy resin, a reactive organophosphorus flame retardant (DPDDM) was designed and synthesized, which was derived from 3,4-dihydroxybenzaldehyde, 4, 4′- diamino diphenylmethane and 9,10-dihydro-9-oxa –10- phosphaphenanthrene-10-oxidein two steps. Compared with neat epoxy resin (EP), the tensile strength and flexural strength of the EP with 5% DPDDM increased by 28.6% and 42.8%, respectively, indicating that DPDDM can significantly improve the mechanical properties of EP materials. Meanwhile, the DPDDM modified EP materials have good transparency and the EP with 5% DPDDM passed the V-0 rating and had the limiting oxygen index as high as 34%. Cone calorimeter test results showed that the heat release and smoke generation of the modified materials were significantly lower than the unmodified materials, which were reduced by 32.6% and 64.6%, respectively, indicating that the modified materials can greatly improve the safety of fire prevention. This work provides a new approach to prepare transparent epoxy resin with good mechanical properties and excellent flame retardancy.     

包覆态和共混态磷酸酯/无机体系阻燃性能研究

研究了氢氧化镁、氢氧化铝或二氧化硅包覆笼状磷酸酯微胶囊以及上述3种无机阻燃剂和笼状磷酸酯复配共混用于阻燃环氧树脂的性能。采用极限氧指数,垂直燃烧（UL94）以及热分析（TG/DTG）对比了各阻燃体系的阻燃协效性能和热行为。结果表明,3种无机物在复配共混体系中都和笼状磷酸酯有较好的协同阻燃作用,而在包覆体系中阻燃性能都较差。添加量都为20 %（17 %笼状磷酸酯和3 %无机阻燃剂）,复配共混体系阻燃环氧树脂的极限氧指数可达32 %,且都可以达到UL94 V0级;而相应包覆微胶囊体系阻燃环氧树脂的极限氧指数约为24 %,阻燃级别仅达UL94 V2级。     

用于环氧树脂磷-氮阻燃固化剂的合成及应用

以1,2-环己二胺(DACH)和苯基膦酰二氯(PPDC)为原料合成了一种新型环氧树脂(EP)阻燃固化剂苯基膦酰-1,2-环己二胺(PPDAC),并用傅里叶变换红外光谱(FTIR)、氢核磁共振(~1HNMR)和热重分析仪(TGA)对其进行了表征,制备了系列PPDAC/EP,采用TGA、极限氧指数(LOI)、垂直燃烧试验和扫描电镜(SEM)研究了其热稳定性、阻燃性和炭层形貌。结果表明:PPDAC的填充可以提高EP树脂的阻燃性能,添加PPDAC的EP残炭率和阻燃性均得到提高,但其初始分解温度和力学性能下降。添加PPDAC的EP残炭表面发泡膨胀明显,阻燃效果优异。     

环氧树脂的改性研究进展

环氧树脂（EP）是一类应用非常广泛的热固性树脂,在国名经济的发展中占有重要地位,本文综述了改性环氧树脂的最新研究状况,概述了环氧树脂的耐热改性、增韧改性以及阻燃性方面的研究进展,并对环氧树脂改性的新方法进行了展望。     

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.