Synergistic Effects of Iron Alginate on Improving the Fire Safety and Mechanical Properties of Epoxy Resin/Ammonium Polyphosphate Composites

Iron alginate is chosen as an eco-friendly synergist to improve the flame retardancy, smoke suppression, and mechanical properties of epoxy resin/ammonium polyphosphate composites (EP/APP). The suitable additive amount of iron alginate further enhances the char-forming ability in the higher-temperature range and flame retardancy of EP/APP. EP/APP_9.0-iron alginate_1.0 retains a char residue of 33.3% at 700 °C and obtains a limiting oxygen index value of 28.4% and vertical burning test (UL-94) V-0 rating, while EP/APP₁₀ has no UL-94 rating. The burning behaviors of EP/APP_9.0-iron alginate_1.0 are also suppressed; and the total smoke production value is much lower than that of EP/APP₁₀. EP/APP_9.0-iron alginate_1.0 releases less smoke and flammable fragments. The suitable additive amount of iron alginate boosts the mechanical properties of EP/APP, while APP destroys the mechanical properties of EP. Therefore, the addition of suitable amount of iron alginates can further reduce the fire hazard, and improve the mechanical properties of EP/APP composites.     

A DOPO Derivative Constructed by Sulfaguanidine and Thiophene toward Enhancing Fire Safety,Smoke Suppression,and Mechanical Properties of Epoxy Resin

In order to eliminate the negative effect of traditional 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) -based flame retardants on heat resistance, mechanical properties, and curing process of epoxy resin (EP), a DOPO derivative (DST) constructed by sulfaguanidine and thiophene is designed and used as co-cured agent for EP. Compared with EP, the maximum decrease of glass transition temperature (T_g) in all EP/DST samples is less than 5%, indicating EP modified by DST maintains good heat resistance. Encouragingly, DST shows satisfactory flame-retardant efficiency and excellent smoke suppressing effects. EP containing barely 5 wt% of DST (P content: 0.37 wt%) achieves a UL-94 V-0 rating and 32.8% limited oxygen index (LOI) value. Its peak heat release rate (PHRR), total heat release (THR), and total smoke production (TSP) are also decreased by 31.2%, 18.8%, and 30.2% . Further, DST significantly improves mechanical properties of the EP/DDM/DST system. The tensile strength and modulus increase by 37.2% and 14.6%, respectively, as DST content is 7.5 wt%. It is revealed that DST has positive quenching and diluting effects in the gas phase, as well as promoting the formation of a compact char layer in the condensed phase.     

反应型和添加型含磷阻燃剂阻燃环氧树脂的性能研究

研究了不同填充量的反应型和添加型含磷阻燃剂对阻燃环氧树脂力学性能和阻燃性能的影响,并对比研究了2种类型阻燃环氧树脂的热稳定性。结果表明,反应型阻燃剂中9,10-二氢-9-氧-10-磷杂菲-10-氧化物（DOPO）阻燃环氧树脂的力学性能和阻燃性能好于6-氢-二苯并[c,e][1,2]氧磷酰杂-6-甲醇,6-氧化物（DOPO-CH2OH）,添加型阻燃剂中三聚氰胺磷酸盐（MP）阻燃环氧树脂的性能好于聚磷酸铵（APP）;2种类型阻燃剂相比,2种反应型阻燃剂阻燃环氧树脂的力学性能、阻燃性能和热稳定性均好于添加型的MP和APP阻燃剂。     

固化体系对环氧树脂阻燃性能影响的研究

比较了间苯二胺（m-PDA）、4,4-二氨基二苯甲烷（DDM）、甲基四氢邻苯二甲酸酐（MeTHPA）三种固化剂与双酚A型环氧树脂（E-51）形成的固化体系燃烧性能的差异,研究了DDM、MeTHPA固化体系对聚磷酸铵（AP462）阻燃环氧树脂燃烧性能的影响。结果表明,DDM固化体系与AP462有良好的协同阻燃效果,仅添加质量分数为25％的AP462,EP-AP462-25／DDM体系的氧指数就可达到41．0％。热失重分析指出,协同阻燃与EP／DDM和AP462的热稳定性匹配、相互作用导致成炭量提高有关。     

微胶囊红磷阻燃剂在环氧树脂基电子电气封装材料中的应用研究

研究了微胶囊红磷对环氧树脂基电子电气封装材料的阻燃性能、力学性能及抑烟性能的影响。添加微胶囊红磷10份量即可使材料的阻燃性能达UL94V 0级,氧指数(LOI)从19 5上升到28 2;添加量在一定范围内对材料的力学性能影响很小,随添加量从0增加至14份,材料的拉伸强度略有下降,从48 84MPa下降至46 92MPa;冲击强度有所上升,从9 29kJ·m-2提高到10 28kJ·m-2;弯曲强度先略有上升然后有所降低,从130 2MPa变化至136 6MPa;微胶囊红磷与硼酸锌的复配体系具有很好抑烟性能。     

Synthesis of a DOPO Derivative to Improve the Fire Safety and Mechanical Performance of Epoxy Resin

A 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) derivative is prepared. At first, an intermediate 4,4'-((triazole)bis(azaneylylidene)bis(2,6-dimethoxyphenol)) (SGA) is obtained from the Schiff-base reaction between syringaldehyde (S) and 3,5-diamino-1,2,4-triazole (GA). The further product DOPO-SGA is then introduced into epoxy by blending to improve flame retardancy and mechanical properties. The flammability evaluation is implemented by limited oxygen index (LOI), UL-94, and cone calorimeter tests. The presence of 3wt.% DOPO-SGA increases the LOI to 33.2%, upgrades the UL-94 rating to V-0, and reduces the release of smoke and heat of epoxy. The tensile strength and impact strength are also enhanced after the introduction of DOPO-SGA. The addition of 5% DOPO-SGA increases the tensile strength and impact strength by 47% and 42%, respectively, compared with that of the control EP sample. It is suggested that the mechanical strengthening is ascribed to the ternary cross-linked network among epoxy monomer, curing agent, and DOPO-SGA. This work provides a feasible solution to obtain flame-retardant epoxy resin with enhanced mechanical performance.     

一种高温环氧树脂的工艺及力学性能

对比研究了国产MERICAN 3768和国外CYCOM 890 RTM两种高温环氧树脂的工艺性和力学性能。同时选取典型航空结构,采用双轴向碳纤维织物和真空灌注工艺制备了对比零件。结果表明,国产MERICAN 3768树脂的浸润性、流变固化特性和力学性能均与国外CYCOM 890 RTM树脂相当,均具有优异的工艺性和力学性能,与纤维匹配性好,满足航空应用对树脂的要求。     

Flame Retardancy and Mechanical Properties of Bio‐Based Furan Epoxy Resins with High Crosslink Density

This work outlines an interesting approach to bioepoxy resins from sustainable 2,5‐bis((oxiran‐2‐ylmethoxy)methyl)furan (BOF). The 3,3′‐diamino diphenyl‐sulfone (33DDS) and 4,4′‐diamino diphenyl‐sulfone (44DDS) are employed as hardeners. For comparison, petro‐based networks from diglycidyl ether of bisphenol A (DGEBA) are developed as well. The systematic analyses suggest that the BOF/DDS networks show higher crosslink densities and mechanical properties than DGEBA/DDS thermosets. Remarkably, an attractive multilayer tubular microstructure is fabricated in the BOF/44DDS thermosets, and it greatly enhances the mechanical performance. Apart from that, BOF/DDS composites exhibit excellent flame retardancy. Especially, for BOF/44DDS, the self‐extinguishment happens in 7 s. The fire retardant mechanism confirms that a low heat release rate and heat release capacity as well as a compact char layer occur in the pyrolysis of BOF/DDS. Thus, the BOF/DDS exhibits superior performance over its DGEBA counterparts and meets a wide variety of requirements in engineering.     

环氧树脂/二烷基次膦酸铝阻燃体系的制备和性能

着重研究了环氧树脂/二乙基次膦酸铝（EP/OP930）阻燃材料的阻燃性能、热分解性能和力学性能。结果表明,OP930的含量仅需15 %（质量分数,下同）就可以使EP/OP930体系的极限氧指数达到29.8 %,垂直燃烧实验达到UL 94 V-0级标准;此外,EP/OP930体系的综合性能良好,不同OP930含量的阻燃材料的力学性能、热稳定性能与原材料相比变化不大。     

微胶囊红磷的制备及其阻燃环氧树脂的性能研究

以预先合成的密胺甲醛树脂预聚物为壳,通过原位聚合法制备了微胶囊红磷,采用扫描电镜观察到微胶囊红磷颗粒表面包覆一层网状的壳材料。研究了红磷和微胶囊红磷阻燃环氧树脂(EP)的耐热性能、阻燃性能及力学性能。结果表明,微胶囊红磷阻燃EP的耐热性和质量保持率明显提高,添加质量分数10%的微胶囊红磷的阻燃EP的阻燃性能达到UL 94 V–0级,其阻燃性能优于红磷阻燃EP。微胶囊红磷阻燃EP的拉伸强度为30.3 MPa,冲击强度为11.4 kJ/m2,分别比相同用量红磷阻燃EP提高了6.0%和21.3%,其冲击强度比纯EP提高了17.5%,表明微胶囊红磷与基体树脂间的相容性大大改善,可显著提高材料的韧性。     

含硅聚氨酯预聚物接枝DOPO改性环氧树脂的制备及性能研究

以端羟基硅油和甲苯二异氰酸酯合成的端异氰酸根聚氨酯预聚物（PUP），对9，10-二氢-9-氧杂-10-磷杂菲-10-氧化物（DOPO）改性的环氧树脂进行接枝改性，制备出兼具韧性和阻燃性的新型环氧树脂。对产物的结构进行了傅里叶红外光谱表征，通过热重分析及氧指数测试对产物的阻燃性能进行了表征，并用冲击强度测试和扫描电子显微镜对增韧效果进行了评价。结果表明，当DOPO含量为15％（摩尔分数，下同）、PUP含量为10％时，产物的阻燃性能和韧性最好，其氧指数达到29，4％，冲击强度达到15．9kJ／m^2。     

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.     

环氧灌封材料的阻燃研究动态

介绍了国内外环氧灌封材料的生产现状及其在电子封装业中的发展前景,并概述了对现代电子封装材料的环保新要求及电子封装无卤化阻燃对环氧树脂提出的挑战。     

Design of Hierarchically Tailored Hybrids Based on Nickle Nanocrystal-Decorated Manganese Dioxides for Enhanced Fire Safety of Epoxy Resin

A novel and hierarchical hybrid composite (MnO₂@CHS@SA@Ni) was synthesized utilizing manganese dioxide (MnO₂) nanosheets as the core structure, self-assembly chitosan (CHS), sodium alginate (SA) and nickel species (Ni) as surface layers, and it was further incorporated into an epoxy matrix for achieving fire hazard suppression via surface self-assembly technology. Herein, the resultant hybrid epoxy composite possessed an exceptional nano-barrier and synergistic charring effect to aid the formation of a compact layered structure that enhanced its fire-resistive effectiveness. As a result, the addition of only 2 wt% MnO₂@CHS@SA@Ni hybrids led to a dramatic reduction in the peak heat release rate and total heat release values (by ca. 33% and 27.8%) of the epoxy matrix. Notably, the peak smoke production rate and total smoke production values of EP/MnO₂@CHS@SA@Ni 2% were decreased by ca. 16.9 and 38.4% compared to the corresponding data of pristine EP. This was accompanied by the suppression of toxic CO, NO release and the diffusion of thermal pyrolysis gases during combustion through TG-IR results. Overall, a significant fire-testing outcome of the proposed hierarchical structure was proven to be effective for epoxy composites in terms of flammability, smoke and toxicity reductions, optimizing their prospects in other polymeric materials in the respective fields.     

含磷有机硅氧烷改性环氧树脂酚醛固化体系性能研究

首先用 -环氧丙氧基三甲氧基硅氧烷和亚磷酸二乙酯（DEP）制备了一种含磷有机硅氧烷(GPTMS-DEP),并对其改性的环氧树脂酚醛固化体系的阻燃性、耐热性及相容性进行了研究。结果表明,固化物的极限氧指数达到30 %;玻璃化转变温度为157 ℃,比纯环氧树脂提高了约45 ℃;在720℃的残炭量及失重50 %时的温度均比纯环氧树脂有明显提高;扫描电子显微镜照片显示,当GPTMS-DEP含量在20 %以下时,GPTMS-DEP改性环氧树脂各组分间相容性良好。     

磷-氮阻燃固化剂的合成及对环氧树脂性能影响

以苯膦酰二氯(PPDC)和间苯二甲胺(MXDA)为原料,合成了一种磷-氮阻燃固化剂(PPMXD)。采用FTIR、1HNMR、ESI-MS、TGA和DSC对该化合物进行了表征。考察了原料物质的量比、溶剂种类及配比、反应温度、反应时间对PPMXD产率的影响。结果表明,PPMXD的最佳合成条件为:反应温度为20℃,反应时间为7 h,n(PPDC)∶n(MXDA)=1.0∶3.5,采用N,N二甲基甲酰胺(DMF)与二氯甲烷体积比为1∶17的混合液作为溶剂,m(溶剂)∶m(PPDC)=12∶1。将PPMXD应用于环氧树脂(E-51)的固化及阻燃,用TGA和SEM对复合材料的热性能及残炭结构进行了表征,通过极限氧指数(LOI)和垂直燃烧(UL-94)实验表征了试样的阻燃性能。当PPMXD添加量为40%(以E-51的质量为基准)时,样品EP2的LOI达到29.0%,可通过UL-94 V-0测试,拉伸强度和冲击强度分别达到42.89 MPa和6.45 k J/m~2。TGA结果显示,PPMXD的加入使EP2最大热失重速率由纯E-51的18.23%/min降低到12.73%/min,800℃时的残炭量由16.12%提高到18.86%。SEM结果表明,环氧树脂燃烧后残炭表面粗糙,发泡明显,PPMXD对环氧树脂表现出了良好的阻燃性能。     

A Novel DOPO‐Based Diamine as Hardener and Flame Retardant for Epoxy Resin Systems

10‐Ethyl‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide ( 1 ) can be nitrated using acetic anhydride and fuming nitric acid. The nitro group is reduced using palladium on charcoal and hydrogen. These reaction conditions are used for the synthesis of an analogous DOPO‐based diaminic hardener ( 7 ). An evaluation of the curing behavior, mechanical properties and flammability of a neat resin made of DGEBA and 7 (DGEBA + 7 ) and of a carbon fiber‐reinforced resin made of DGEBA, 4,4′‐diaminodiphenylsulfon (DDS) and 7 (DGEBA + DDS + 7 ) shows the potential of this hardener to lead to flame‐retardant systems while keeping relevant properties on a high level; especially when compared to a similar system (DGEBA + DDS + 1 ).

     

含三聚氰胺有机硅杂化物的环氧树脂性能研究

利用羟甲基化三聚氰胺和γ-环氧丙氧基三甲氧基硅烷反应制备了三聚氰胺有机硅杂化物,并用FTIR、29S iNMR对其结构进行了表征。然后将其与环氧树脂共混固化,对固化物热性能、阻燃性、力学性能进行了分析。结果表明,该三聚氰胺有机硅杂化环氧树脂固化物不仅保持纯环氧树脂玻璃化转变温度,而且在空气和氮气中的热失重分析显示,高温区域的热稳定性及残碳率比纯环氧树脂高;三聚氰胺有机硅杂化环氧树脂固化物的极限氧指数达到30.2,与纯环氧树脂相比,该固化物的极限氧指数提高了43%左右,抗冲击强度有较大幅度的提高,当三聚氰胺有机硅杂化物的添加量为环氧树脂质量的5%时,环氧树脂固化物的抗冲击强度达到20.3 kJ/mol;扫描电子显微镜照片显示三聚氰胺有机硅杂化环氧树脂的韧性较纯环氧树脂有很大提高。     

新型P-Br阻燃剂对环氧树脂阻燃和力学性能的影响

研究了一种新型P-Br阻燃剂-1,3,5－三（5,5－二溴甲基－1,3－二氧杂己内磷酰氧基）苯(FR)的含量对环氧树脂(EP)的阻燃性能和力学性能的影响。结果表明,当阻燃剂FR的含量为15 %（质量分数,下同）时,与纯EP相比,阻燃EP的极限氧指数从25.0 %提高到29.3 %,垂直燃烧通过UL 94 V-0级,火势增长指数从3.63 kW/(m2·s1)下降到0.77 kW/(m2·s1),放热指数从1.89 MJ/m2下降到1.34 MJ/m2,600 ℃残炭率从18.54 %升至29.02 %,呈现良好的阻燃效果,但力学性能有所下降,拉伸强度从62.04 MPa下降到39.81 MPa,冲击强度从13.46 kJ/m2 降到10.13 kJ/m2。     

环氧树脂／凹凸棒土复合材料的分散和力学性能研究

采用超声分散和溶液共混的方法制备环氧树脂/凹凸棒土复合材料。电子显微镜和元素分析的结果表明，超声分散和凹凸棒土的有机化处理可以改善凹凸棒土的团聚状况和亲油性。选用超声波的作用功率为400W，作用时间为5min时的分散条件，复合材料的冲击强度、弯曲强度和弯曲模量均高于环氧树脂，表明凹凸棒土在复合材料中起到了增强的作用。