Preparation and properties of novel epoxy/graphene oxide nanosheets (GON) composites functionalized with flame retardant containing phosphorus and silicon

2-(Diphenylphosphino)ethyltriethoxy silane (DPPES) was grafted onto the surface of graphene oxide nanosheets (GON) via a condensation reaction. X-ray photoelectron spectroscopy, X-ray diffractometry, Fourier transform infrared spectroscopy and Raman spectroscopy verify that DPPES did not only covalently bond to GON as a functionalization moiety, but partly restored its conjugated structure as a reducing agent. DPPES on graphene sheets oxide was observed by transmission electron microscopy, and contributed to the favorable dispersion of DPPES-GON in nonpolar toluene. Additionally, the flame retardancy and thermal stability of epoxy/DPPES-GON nanocomposites that contain various weight fractions of DPPES-GON were studied using the limiting oxygen index test, UL-94 test and by thermogravimetric analysis in nitrogen. The composites containing 10 wt% DPPES-GON can pass V-0 rating in UL-94 test. Adding 10 wt% DPPES-GON in epoxy greatly increased the char yield and LOI by 42% and 80%, respectively. Epoxy/DPPES-GON nanocomposites with phosphorus, silicon and graphene layer structures were found to exhibit much greater flame retardancy than neat epoxy. The synergistic effects among silicon, phosphorus and GON can improve the flame retardancy of epoxy resin.     

磷杂菲三氮唑双基化合物高效阻燃环氧树脂

以对苯二甲醛、3,5-二氨基-1,2,4-三氮唑和9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)为原料合成了一种磷杂菲三氮唑双基化合物(DTZ),将其用于高效阻燃环氧树脂。利用FTIR、NMR、GPC和元素分析表征了其分子结构,采用TG和DSC研究了环氧固化物的热性能,利用极限氧指数、垂直燃烧、锥形量热、拉伸性能测试仪探究了环氧固化物的阻燃和力学性能,通过分析DTZ的热裂解行为、热氧化降解行为及炭层的形貌和结构研究了其阻燃机制。结果表明,DTZ的引入会降低环氧固化物的起始降解温度和玻璃化温度,但会提高其高温残炭率和拉伸强力。DTZ可显著提升环氧固化物的阻燃性能,当添加量为6wt%时,所得固化物的极限氧指数(LOI)值为33.5%,UL-94测试等级达到V-0级,热释放速率峰值和总热释放量分别降低21.8%和18.2%。DTZ可通过猝灭自由基、稀释可燃气体、促进基体成炭,在气相和凝聚相同时发挥阻燃作用。      

三聚氰胺氰尿酸盐与聚磷酸铵协同作用对环氧树脂阻燃性能的影响

采用氧指数法（LOI）、垂直燃烧法（UL-94）及热重分析法（TGA）对三聚氰胺氰尿酸盐（MCA）和聚磷酸铵（APP）阻燃环氧树脂的阻燃性及热稳定性进行了研究。TGA结果表明,MCA促进成炭的作用较弱,主要在气相起到阻燃的作用。而APP的添加虽然降低了环氧树脂的初始分解温度,但当温度高于400℃时,体系具有更好的热稳定...     

环氧树脂/聚磷酸铵复合材料的阻燃性能与热降解行为

利用环氧树脂(EP)成炭能力,引入聚磷酸铵(APP)以提高其阻燃性能。当APP质量分数为9%时,EP/APP氧指数达30.5%,垂直燃烧性能通过V-0级。相比EP,EP/APP的热释放峰值与总热释放均有所下降。此外,利用热失重-红外联用设备研究了EP以及EP/APP的热降解行为并解释相关机理:EP在高温下会释放CO、甲醇等易燃性气体,剧烈燃烧并放出大量的热;APP在低温阶段的热裂解产物会催化EP的降解,但在高温下EP/APP却有热稳定性优异的炭层形成,在火灾中此炭层会覆盖在基体表面保护下部材料以免其遭到进一步的破坏。     

六(γ-氨丙基硅烷三醇)环三磷腈的制备及其在膨胀阻燃聚丙烯中的应用

以六氯环三磷腈、对羟基苯甲醛及γ-氨丙基硅烷三醇(KH553)为反应原料,合成了具有席夫碱结构的有机硅型成炭剂六(γ-氨丙基硅烷三醇)环三磷腈(HKHPCP)。以HKHPCP与聚磷酸铵(APP)的复配物为抗熔滴剂,以N-烷氧基受阻胺(NOR116)为阻燃协效剂,通过熔融共混技术制备了膨胀阻燃聚丙烯(PP)基复合材料(APP-HKHPCP-NOR116/PP)。利用FTIR、核磁共振(1 H和31P NMR)对HKHPCP的化学结构进行了表征。采用热失重、极限氧指数、垂直燃烧、锥形量热、拉曼光谱和SEM研究了阻燃体系的热降解行为、阻燃性能及炭层的石墨化程度和致密性。HKHPCP的热失重结果表明,其在氧气氛围下的初始分解温度为300.2℃,1 000℃时残余率为34.8%。当添加总量为30wt%的阻燃剂时,APP-HKHPCP-NOR116/PP复合材料的极限氧指数(LOI)达到43%,且能通过UL-94V-0级,其热释放速率(HRR)、总热释放速率(THR)及烟释放速率(SPR)、总烟释放量(TSP)相比于纯PP分别降低了75.0%、50.5%和88.0%、80.8%,表现出显著的隔热、抑烟性能。APPHKHPCP-NOR116/PP复合材料燃烧后形成了高石墨化、致密的炭层。     

基于微胶囊化聚磷酸铵和微胶囊化膨胀石墨的阻燃硬质聚氨酯泡沫复合材料的制备及性能

采用原位聚合法,以聚氨酯为壳材,制备微胶囊化聚磷酸铵(PUAPP)和微胶囊化膨胀石墨(PUEG)。采用XPS、FTIR、TG和SEM分别对PUAPP和PUEG进行表征,结果表明,聚氨酯有效包覆在聚磷酸铵和膨胀石墨表面,成功制备了PUAPP和PUEG。在此基础上,采用一步法全水发泡工艺将PUAPP和PUEG引入到聚氨酯硬泡(RPUF)中,制备出一系列阻燃RPUF复合材料。采用极限氧指数(LOI)、垂直燃烧(UL-94)、TG、万能试验机、导热及密度测试研究了PUAPP/RPUF、PUEG/RPUF及PUAPP-PUEG/RPUF复合材料的阻燃性能、力学性能、保温性能及热稳定性。研究表明,微胶囊化阻燃剂的加入可以提高RPUF复合材料的高温稳定性,PUEG/RPUF、PUAPP/RPUF和PUAPP-PUEG/RPUF复合材料在700℃的残炭率从1.2wt%分别提高至6.9wt%、11.2wt%和10.7wt%。阻燃测试表明,PUAPP和PUEG可以有效提高RPUF复合材料的阻燃性能,当加入10.4wt% PUAPP时,PUAPP/RPUF复合材料的LOI提高到22.3vol%,UL-94等级为V-0级;当加入10.4wt% PUEG时,PUEG/RPUF复合材料的LOI达到25.3vol%,UL-94等级为V-0级;PUAPP-PUEG/RPUF复合材料的LOI达到24.3vol%,UL-94等级为V-0级。SEM和拉曼测试表明,PUAPP和PUEG可以提高RPUF复合材料的炭渣石墨化程度,使炭渣的致密性更强。      

分子筛/受阻胺对膨胀阻燃聚丙烯的协同阻燃作用

采用热失重、极限氧指数、锥形量热研究了以受阻胺(NOR116)和分子筛为协效剂,与聚磷酸铵(APP)/季戊四醇(PER)在聚丙烯基体中的热降解行为及协同阻燃性;并用拉曼光谱和扫描电镜分析了残炭的结构和形貌,进一步研究了其协同阻燃机理。结果表明,NOR116/分子筛协效阻燃体系可明显提高极限氧指数并改善燃烧时熔滴缺陷,显著降低热释放速率、烟释放速率;NOR116可有效提高PP的初始分解温度及最大分解速率温度,使膨胀阻燃体系后期的交联成炭及气体释放更加匹配;在燃烧过程中分子筛与膨胀阻燃体系形成了Si-P-Al-C的结构,可有效稳定炭层;拉曼光谱及扫描电镜结果表明,NOR116和分子筛可促进膨胀阻燃体系形成致密且高石墨化程度的炭层,有效阻隔了氧气的进入及热的反馈。     

Preparation of a Novel Phosphorus–Nitrogen-Containing Flame Retardant by Supramolecular Reaction and its Application in Epoxy Resin

Piperazine hexahydrate (PI) and diethylenetriamine penta(methylene phosphonic acid) (DTPMP) are used to synthesize flame-retardant PI-DTPMP through supramolecular reaction. The incorporation of PI-DTPMP simultaneously improves the mechanical and flame-retardant properties of epoxy resin (EP). With only 5 wt% loading of PI-DTPMP, EP composites show excellent flame retardancy with a limiting oxygen index (LOI) of 36.4% and V-0 rating in the UL-94 test. The cone calorimetric test results demonstrates that the peak heat release rate, total heat release, and total smoke release of EP/5%PI-DTPMP are reduced by 44.9%, 34.7%, and 37.7% compared with that of neat EP, respectively, owing to the formation of compact and insulating char layer during combustion. Moreover, EP/PI-DTPMP composites show enhanced mechanical properties with the improved tensile and impact strength, as well as higher storage modulus, crosslink densities, and glass-transition temperatures in dynamic mechanical analysis.     

苯基膦酸铈与十溴二苯醚阻燃玻璃纤维增强聚对苯二甲酸乙二醇酯复合材料

通过熔融共混方法制备苯基膦酸铈（CeHPP）与十溴二苯醚（DBDPO）复配阻燃玻璃纤维增强聚对苯二甲酸乙二醇酯（GF/PET）复合材料。采用热失重分析（TGA）测试研究了DBDPO-CeHPP对GF/PET复合材料热稳定性的影响。同时利用垂直燃烧（UL-94）、极限氧指数（LOI）及微型锥形量热（MCC）测试表征DBDPO-CeHPP-GF/PET复合材料的阻燃性能。使用SEM对DBDPO-CeHPP-GF/PET复合材料的残炭表面形貌进行观察分析。结果表明,DBDPO与CeHPP复配后对DBDPO-CeHPP-GF/PET体系的热性能和阻燃性能都有很大的影响。其中,GF/PET复合材料与DBDPO和CeHPP质量比为91:6:3时,DBDPO-CeHPP-GF/PET复合材料的LOI高达29.5%,可以通过UL-94 V-0级。在MCC测试中,与纯GF/PET复合材料相比,该配比的DBDPO-CeHPP-GF/PET复合材料总热释放（THR）、热释放速率峰值（PHRR）及热熔（HRC）分别下降了10.2%、13.1%和12.8%。结合残炭形貌的测试结果,对DBDPO-CeHPP-GF/PET复合材料的阻燃机制进行了适当的解释分析。      

有机蒙脱土协同含磷木质素基成炭剂阻燃聚乳酸

将自制含磷木质素基成炭剂（Lig-P）和聚磷酸铵（APP）复配用于制备阻燃聚乳酸（PLA）基复合材料,考察了协效阻燃剂有机蒙脱土（OMMT）对阻燃PLA性能的影响。采用极限氧指数（LOI）仪、垂直燃烧（UL-94）测试仪、锥形量热仪、热失重分析仪分别对Lig-P-APP-OMMT/PLA阻燃复合材料的阻燃性能、热稳定性能和燃烧行为进行了研究。结果发现,OMMT与Lig-P-APP存在明显的协同阻燃作用,当OMMT替代3wt%的Lig-P-APP时,Lig-P-APP-OMMT/PLA阻燃复合材料的LOI由27%增加至32%,UL-94等级由V1级提高至V0级;且Lig-P-APP-OMMT/PLA阻燃复合材料的最大热降解速率有所降低,800℃的残炭量提高了将近50%;此外,OMMT的引入使PLA阻燃复合材料的热释放速率明显降低,热释放速率峰值（PHRR）、烟释放速率峰值（PSPR）及总烟释放量（TSR）分别降低了26.4%、60%及26.3%。OMMT可明显提高阻燃PLA炭层的致密度及石墨化程度。      

纳米膨胀阻燃季戊四醇二磷酸酯双磷酰蜜胺有机改性蒙脱土/聚乳酸复合材料的制备及阻燃性能

将一种高效膨胀型无卤阻燃剂季戊四醇二磷酸酯双磷酰蜜胺(SPBDM)和有机改性蒙脱土(OMMT)添加到高分子量聚乳酸(PLA)中,熔融共混制备纳米膨胀型阻燃聚乳酸复合材料(SPBDM-OMMT/PLA)。采用XRD、TEM研究了纳米粒子的形态分布,并用热重分析法(TGA)、氧指数测试(LOI)、垂直燃烧测试(UL-94)探讨了该纳米阻燃SPBDM-OMMT/PLA复合材料的热性能和阻燃性能。研究表明,OMMT在PLA基体中有较好的分散性,高分子链插入层状硅酸盐片层间,形成了剥离型或插层型复合材料;相比纯PLA,加入SPBDM后改善了OMMT/PLA的高温热稳定性,最大热分解温度均向高温移动,且高温残炭质量分数大幅度提高;当SPBDM和OMMT质量分数分别为10.0%和1.0%时,纳米阻燃SPBDM-OMMT/PLA复合材料能达到较好的阻燃效果,LOI数值高达32%,相应垂直燃烧等级达UL-94V-0级。     

聚磷酸铵及季戊四醇膨胀型阻燃环氧树脂的阻燃性能

研究了聚磷酸铵(APP)和季戊四醇(PER)阻燃环氧树脂的阻燃性能和热分解特性。结果表明,阻燃环氧树脂的氧指数(LOI)随APP含量的增加而增加;当APP添加量达到20%时,阻燃环氧树脂的垂直燃烧性能达到V-0级。在APP阻燃环氧树脂中引入成炭剂PER使得体系的LOI值有所降低,但适量PER的引入使得阻燃体系的最大热释放速率降低。热失重(TG)实验结果表明,与未阻燃的环氧树脂相比,阻燃环氧树脂的初始分解温度有所降低,但在高温下阻燃环氧树脂的热稳定性较好。此外,还采用了激光拉曼光谱对阻燃环氧树脂燃烧后的炭层进行了分析。     

苯基次膦酸铝用于玻纤增强PBT的无卤阻燃

采用一种新型次膦酸盐阻燃剂苯基次膦酸铝复配三聚氰胺焦磷酸盐对玻纤增强聚对苯二甲酸丁二醇酯(PBT)进行无卤阻燃改性。通过热重分析研究了阻燃剂的加入对体系热分解过程的影响,通过氧指数、UL-94垂直燃烧及锥形量热测试研究了阻燃体系的阻燃性能。研究表明,苯基次膦酸铝与三聚氰胺焦磷酸盐复配比例为1∶1时阻燃效果最好,材料氧指数达到26.0%,通过UL-94 V-0级,同时样品热释放速率HRR降低至146 kW/m2,热重分析表明,两种阻燃剂之间通过化学反应促进了材料的提前分解,有利于在材料表面形成保护性炭层,从而提高了材料的阻燃性能。     

Flame-retarded biocomposites of poly(lactic acid), distiller’s dried grains with solubles and resorcinol di(phenyl phosphate)

The distiller’s dried grains with solubles (DDGS) were treated by smashing and water washing processes. The treatment effects on DDGS were analyzed, and the results showed that the thermal stability and the hydrophobicity of DDGS were improved by the treatment processes. The flame retarded biocomposites of poly(lactic acid) (PLA) with DDGS and degradable polymeric flame retardant resorcinol di(phenyl phosphate) (RDP) were prepared. The prepared biocomposites had good mechanical properties and the tensile strength of the biocomposite containing 15 wt% RDP and 15 wt% DDGS reached approximately 53 MPa. Meanwhile, using the limited oxygen index (LOI) and the underwriters laboratory (UL-94) tests, for the biocomposite, the LOI value was approximately 27.5% and V-0 rating in UL-94 was attained. Furthermore, the peak heat release rate of this biocomposite was reduced to 275 kW/m² compared with 310 kW/m² for pure PLA. After burning of the biocomposites, compact and coherent charred layer was formed and the char residues were analyzed in detail.     

硼-氮阻燃剂与氢氧化镁协同阻燃环氧树脂

将硼-氮阻燃剂2,4,6-三(4-硼酸-2-噻吩)-1,3,5-三嗪(3TT-3BA)与Mg(OH)_2进行复配,然后将其添加到环氧树脂(EP)中,通过热重分析、锥形量热、极限氧指数、垂直燃烧等测试方法,研究了3TT-BA/Mg(OH)_2复配体系对EP的阻燃性能。研究发现,3TT-3BA与Mg(OH)_2具有协同阻燃作用,添加10%3TT-3BA/10%Mg(OH)_2到EP中,其极限氧指数达到了32.5%,垂直燃烧达到了UL94 V-0等级。同时,3TT-BA/Mg(OH)_2复配体系还能有效减小EP热释放速率、热释放总量和生烟总量。通过扫描电镜等手段探讨了3TT-BA/Mg(OH)_2复配体系的阻燃机理。     

微胶囊化膨胀型阻燃剂与有机蒙脱土协效阻燃乙烯-醋酸乙烯共聚物性能

通过纳米复合的方式,将微胶囊化的膨胀型阻燃体系—聚磷酸铵(APP)-季戊四醇(PER)与有机改性的片层蒙脱土(OMMT)用于协效阻燃乙烯-醋酸乙烯共聚物(EVA)。采用XRD、TEM、TGA、极限氧指数(LOI)、垂直燃烧(UL-94)、锥形量热仪、烟密度和动态机械热分析对微胶囊化APP(MCAPP)-微胶囊化PER(MCPER)-OMMT/EVA复合材料的结构与性能进行研究。研究结果表明,OMMT被完全剥离开,并以层离或插层的状态分散在EVA中;MCAPP-MCPER与OMMT之间存在明显的协效阻燃作用,用3wt%OMMT代替MCAPP-MCPER后,MCAPP-MCPER-OMMT/EVA复合材料的LOI值从25.5vol%提高到29.5vol%,垂直燃烧结果由V-2上升到V-0级别,残炭量也由14.5wt%增大到15.9wt%,烟密度由154.7 g/s降低到97.5 g/s,材料的阻燃性能得到有效提高。此外,万能拉伸测试及动态机械热分析测试表明,通过纳米复合制备的阻燃MCAPP-MCPER-OMMT/EVA复合材料具有更好的力学和动态热机械性能。      

阻燃ABS复合材料的制备及热分解性能

以阻燃齐聚物(PSPTR)和酚醛树脂(PF)作为膨胀型阻燃剂(IFR)阻燃丙烯晴-丁二烯-苯乙烯共聚物(ABS), 通过极限氧指数(LOI)和水平垂直燃烧(UL-94)测试研究了阻燃PSPTR-PF/ABS体系的阻燃性能。研究表明, 当PSPTR:PF=1:1(质量比), 总质量分数为30%时, 体系的LOI为28.2%, UL-94达V-1级别。采用热重-红外联用(TG-IR)技术探索了阻燃体系的热性能和热分解历程, 发现PSPTR-PF阻燃剂的加入延缓了ABS的热分解, 提高了ABS的热稳定性能。采用SEM、 XRD和Raman光谱分析了燃烧炭层的形貌和结构。结果表明, PF不仅改善了炭层的致密度, 而且完善了炭层的石墨结构, 最终提高了ABS的阻燃性能。     

Facile synthesis of lanthanum hypophosphite and its application in glass-fiber reinforced polyamide 6 as a novel flame retardant

This work developed flame retarded glass fiber reinforced polyamide 6 (FR-GFPA) composites with excellent mechanical properties, thermal stability and flame retardancy using a novel flame retardant, lanthanum hypophosphite (LaHP). The flame-retarded properties of FR-GFPA composites were characterized by limiting oxygen index, Underwriters Laboratories 94 testing and cone calorimeter test. FR-GFPA composite with 20 wt% LaHP reached V-0 rating and a high LOI value (27.5 vol%). The mechanical performance analysis showed that both the storage modulus and tensile strength increased and then decreased with the increase of LaHP loading. For FR-GFPA composite with 15 wt% LaHP loading, the storage modulus was 164% higher than that of glass fiber reinforced polyamide 6 (GFPA). Thermogravimetric analysis (TGA) and char residue characterization showed that the addition of LaHP can promote the formation of compact physical char barrier, reduce the mass loss rate and thus improve the flame retardancy of FR-GFPA composites.     

无卤阻燃PES热熔胶的制备与阻燃性能

以聚磷酸铵(APP)、季戊四醇(PER)和三聚氰胺(MEL)组成的膨胀阻燃体系(IFR)作为阻燃剂,以4A分子筛作为协效剂,制备了无卤阻燃共聚酯(PES)热熔胶。研究了IFR对PES阻燃性能的影响及4A分子筛的协效作用。结果表明,少量4A分子筛可促进IFR的阻燃作用。IFR添加量为30%时,阻燃PES氧指数达30.7%,垂直燃烧达V-0级,最大热释放速率大幅降低;加入3%的4A分子筛,氧指数达35.1%。热重分析(TG)、扫描电镜(SEM)及X射线光电子能谱(XPS)结果表明,少量4A分子筛可催化IFR酯化反应,促进体系形成致密炭层,高温时4A分子筛分解并参与成炭反应,稳定炭层。     

The effect of graphene presence in flame retarded epoxy resin matrix on the mechanical and flammability properties of glass fiber-reinforced composites

The effect of adding graphene in epoxy containing either an additive (MP) or reactive-type (DOPO) flame retardant on the thermal, mechanical and flammability properties of glass fiber-reinforced epoxy composites was investigated using thermal analysis; flexural, impact, tensile tests; cone calorimetry and UL-94 techniques. The addition of MP or DOPO to epoxy had a thermal destabilization effect below 400 °C, but led to higher char yield at higher temperatures. The inclusion of 10 wt% flame retardants slightly decreased the mechanical behavior, which was attributed to the poor interfacial interactions in case of MP or the decreased cross-linking density in case of DOPO flame retarded resin. The additional graphene presence increased flexural and impact properties, but slightly decreased tensile performance. Adding graphene further decreased the PHRR, THR and burning rate due to its good barrier effect. The improved fire retardancy was mainly attributed to the reduced release of the combustible gas products.