可膨胀石墨/聚磷酸铵协效阻燃PUI泡沫塑料研究

通过添加可膨胀石墨(EG)和聚磷酸铵(APP)单组分阻燃剂及其复配阻燃剂,制备了聚氨酯–酰亚胺(PUI)泡沫塑料阻燃体系,并对其阻燃性能、热性能、表面碳层形貌及力学性能等进行了研究。结果表明,在相同阻燃剂添加量下,复配阻燃体系的极限氧指数(LOI)值高于单一阻燃剂阻燃体系,PUI/EG/APP体系的LOI值由18.6%提高至30.9%。热失重分析表明EG和APP间的相互作用导致了PUI/EG/APP体系在高温阶段的热降解速率下降,残炭率显著上升。扫描电镜分析表明PUI/EG/APP体系在燃烧后能生成更加连续和致密的炭层。在相同阻燃剂添加量的情况下,EG/APP复配使用能够减少EG对PUI压缩性能的损害。     

基于磷杂菲衍生物多组分无卤阻燃天然橡胶的制备及性能

将磷杂菲/三嗪双基协同阻燃剂（TGD）、甲基膦酸二甲酯（DMMP）、可膨胀石墨（EG）及氢氧化铝（ATH）复配添加到天然橡胶（NR）中制备阻燃NR硫化胶,考察了TGD/DMMP/EG/ATH复配阻燃剂对NR硫化胶的阻燃性能、热稳定性及物理机械性能的影响。结果表明,TGD/DMMP/EG/ATH复配阻燃剂可有效提升NR硫化胶的阻燃性能和热稳定性,并降低燃烧过程中的热释放速率。当TGD/DMMP/EG/ATH复配阻燃剂的用量为60份（质量）时,NR硫化胶的极限氧指数可达28.4%,残炭质量分数可达25.61%,热释放速率可降低95%,总热释放量可降低21%。TGD/DMMP/EG/ATH复配阻燃剂对NR硫化胶的物理机械性能影响不大。     

复配阻燃剂对硬质聚氨酯泡沫塑料阻燃性能的影响

研究了甲基膦酸二甲酯(DMMP)、尿素(UC)、磷酸三乙酯(TEP)单独添加及复配使用对硬质聚氨酯泡沫塑料(RPUF)阻燃性能的影响。结果表明,UC与DMMP及TEP复配是气相和凝聚相双相协同阻燃机理的复合阻燃剂;UC与DMMP,UC与TEP复配阻燃RPUF,可达到垂直燃烧分级V0级;UC／DMMP复配使用,UC和DMMP含量分别为15%和25%时,其阻燃RPUF的氧指数最高,为27.3%,阻燃性能优于UC／TEP复配阻燃RPUF;复配阻燃RPUF的压缩强度比单独填充UC体系高,呈现协同作用。     

可膨胀石墨对全水发泡聚氨酯阻燃硬泡综合性能的影响

通过可再生的蓖麻油与甘油进行酯交换反应制备蓖麻油多元醇,并将其应用于聚氨酯阻燃硬泡(RPUF)的制备中,讨论了阻燃型可膨胀石墨(EG)的加入量、复配阻燃剂及复配阻燃剂EG/DMMP中EG与甲基膦酸二甲酯(DMMP)的配比对RPUF综合性能的影响。     

三嗪膨胀阻燃硬质发泡聚氨酯材料的制备及性能研究

将自行研究生产的三嗪膨胀阻燃剂(IFR)添加到聚氨酯中制备阻燃硬质发泡聚氨酯(RPUF)材料,通过极限氧指数(LOI)研究了材料的阻燃性能,通过热重分析(TGA)测试研究了材料的热稳定性和成炭性能,通过扫描电镜(SEM)的测试了材料的泡孔结构及燃烧后炭层的表面形貌,同时还研究了阻燃剂添加量对材料的阻燃性能及压缩强度的影响。结果表明:纯RPUF材料的氧指数仅为18.7%,在空气中极易燃烧。当阻燃剂的添加量为25%时,材料的氧指数值提高到了26.1%,同时IFR的加入使得RPUF材料的压缩强度显著提升。TGA结果表明:阻燃剂的添加使得材料的起始热分解温度有所降低,但材料的残炭量得到了很大程度的提高。SEM结果表明:阻燃剂的加入对RPUF材料的泡孔结构影响不大,同时使材料燃烧后的炭层更加的致密和均匀,从而提高了材料的阻燃性能。     

三元包覆微胶囊化红磷阻燃RPUF的研制

制备了有机-无机三元包覆微胶囊化红磷(TMRP),并将其与甲基磷酸二甲酯(DMMP)复配为阻燃剂制备了硬质聚氨酯泡沫塑料(RPUF),考察了TMRP/DMMP质量比和用量对RPUF的阻燃性能、力学性能、动态力学性能和热失重性能的影响。结果表明;TMRP,DMMP对RPUF有阻燃协同效应,当TMRP/DMMP质量比为1:1时,效果最好;添加TMRP/DMMP质量分数5%后,极限氧指数可达22.5%,垂直燃烧级别达到UL94V-0级,且对弯曲性能影响很小;动力学性能分析表明,TMRP/DMMP的加入略微降低了RPUF的玻璃化转变温度;热失重分析、残炭的红外光谱分析和体式显微镜分析表明,TMRP/DMMP能促进RPUF成炭,形成膨松的炭层,提高RPUF的阻燃性能。     

可膨胀石墨/聚磷酸铵协同阻燃聚苯乙烯的研究

将可膨胀石墨(EG)与聚磷酸铵(APP)复配并添加至聚苯乙烯(PS)基体中,制备了PS/EG/APP阻燃复合材料。通过极限氧指数(LOI)、水平垂直燃烧(UL 94)测试,以及热重分析(TG)和扫描电镜分析(SEM)对PS/EG/APP阻燃复合材料的阻燃性能和热稳定性进行了检测,并优化了该材料配方。结果表明:复合阻燃剂EG/APP的加入,使得体系的LOI值与热稳定性均明显提高。其中当复合阻燃剂EG/APP的添加量为30 phr,且质量比为3:1时,阻燃体系的LOI值可达到31.8%,而单独添加同量EG或APP的阻燃体系,其LOI值仅为29%和20.8%,这说明EG与APP之间存在协同效应。     

AlPi和PPBBA复配阻燃PET的燃烧性能

采用二乙基次膦酸铝(Al Pi)和聚丙烯酸五溴卞酯(PPBBA)复配,提高聚对苯二甲酸乙二酯(PET)的阻燃性能。测定了阻燃PET的极限氧指数(LOI)、垂直燃烧性能、热失重分析、动态流变性能,并采用扫描电子显微镜(SEM)观测了燃烧炭层的形貌。结果表明,Al Pi∶PPBBA分别以5∶5和10∶5复配,添加量分别为10%和15%时,LOI达到28.0%和33.3%,垂直燃烧测试均达到V–0级。复配阻燃体系的加入促进了PET的提前分解,阻燃剂主要在气相发挥阻燃作用,同时有利于成炭。当添加15%复配阻燃剂时,相比于纯PET,阻燃PET的最大分解速率降低21.2%,残炭率提高97.6%,提高了阻燃PET在高温下的热稳定性。在角频率为1 rad/s条件下,当添加10%和15%复配阻燃剂时,体系的复数黏度由39.4 Pa·s分别提高到296 Pa·s和1 970 Pa·s,具有较高的抗熔滴性能。烧结后的残留物高倍膨胀,炭层致密连续。     

EG与BHAPE对RPUF燃烧及成炭作用的影响

制备了可膨胀石墨(EG)和N,N-[双(2-羟乙基)氨甲基]磷酸二乙酯(BHAPE)单独添加及复配使用阻燃的硬质聚氨酯泡沫塑料(RPUF),通过万能拉伸试验机、组合冲击试验机、氧指数仪、综合热分析仪、锥形量热仪和扫描电镜(SEM)等测试,对力学性能、阻燃性、热稳定性、燃烧性能及炭层形貌等进行了分析。结果表明,BHAPE的添加能够改善RPUF的比冲击强度,减少EG对体系力学性能的损害;氧指数(LOI)的实际值明显高于计算值,复配组分的LOI由20.3%提高到29.2%,EG/BHAPE具有显著的协同效应;EG/BHAPE复配使阻燃体系的初始分解温度、最大热解速率、热释放速率、总热及总烟释放量降低,残炭率提高,燃烧后形成厚且致密的炭层。     

反应型含磷多元醇/APP复配阻燃聚氨酯泡沫的制备及性能

以非丁基氧化锡为催化剂,通过甲基膦酸二甲酯(DMMP)与乙二醇(EG)酯交换反应,制备了含磷多元醇(DMMP-EG)。将DMMP-EG与聚磷酸铵(APP)作为复合阻燃剂,制备了阻燃硬质聚氨酯泡沫(RPUF),探讨了复配阻燃剂对RPUF力学性能、阻燃性能、热稳定性的影响。结果表明:DMMP-EG与APP复配阻燃RPUF,在提高阻燃性能的同时,力学性能显著提高;当DMMP-EG添加15份、APP添加30份时,泡沫的力学性能最佳,与纯RPUF相比,压缩强度提高了1.25%,冲击强度提高了101.53%;此时,极限氧指数(LOI)提高至21.7%,烟密度等级为40。热重(TG)分析结果表明:在氮气气氛中,750℃时的残炭率较纯RPUF提高了612.56%。阻燃体系呈现以凝聚相为主的气相-凝聚相双相阻燃特点。     

Effects of expandable graphite and dimethyl methylphosphonate on mechanical,thermal, and flame‐retardant properties of flexible polyurethane foams

Expandable graphite (EG) and dimethyl methylphosphonate (DMMP) were added to polyurethane to form flame‐retardant high‐resilience flexible polyurethane foam (FPUF) in one‐step. The effects of EG and DMMP on cell morphology, mechanical properties, dynamic mechanical properties, thermal degradation, and flame‐retardant properties of FPUF were studied. The results indicated that adding proper amount EG or/and DMMP would not seriously damage cell morphology and mechanical properties. Dynamic mechanical analysis (DMA) demonstrated that there were two tan δ peaks attributed to soft and hard segment seperately and 15 pbw EG or/and 15 pbw DMMP could enhance damping property of FPUF. Thermogravimetric analysis–Fourier transform infrared spectroscopy (TGA–FTIR) results indicated that 15 pbw EG or 15 pbw DMMP could improve the thermal stability of the second degradation step but there were no synergistic effect between the two. DMMP made FPUF composites produce more toxic gases such as CO, however, EG displayed an opposite effect. Both EG and DMMP could effectively improve the flame retardant properties of FPUF, and there was synergistic effect between the two. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 916‐926, 2013     

The flame retardant behaviors and synergistic effect of expandable graphite and dimethyl methylphosphonate in rigid polyurethane foams

A series of flame‐retardant rigid polyurethane foams (RPUFs) containing dimethyl methylphosphonate (DMMP) and expandable graphite (EG) were prepared by box‐foaming. The RPUFs were characterized by thermogravimetric analysis (TGA), the limiting oxygen index (LOI), cone calorimeter, and scanning electron microscope (SEM). The decomposition process of DMMP was investigated by Pyrolysis‐Gas Chromatography/Mass Spectroscopy (Py‐GC/MS). Accordingly, their flame retardant behaviors and mechanism were also discussed. The results show that the DMMP/EG system can linearly enhance the LOI value from 19.2% of the pure RPUF to 33.0% of RPUFs containing 16 wt% flame retardant. In addition, the DMMP/EG system also remarkably increases yields of the residual char and drastically decreases the peak value of heat release rate (PHRR), heat release rate (HRR), total heat release (THR), total smoke release (TSR), and the yields of CO (COY). In the flame retardant RPUFs, when the matrix is ignited, the flame retardant DMMP should be decomposed to gaseous PO₂ fragments, which can inhibit free radical chain reaction of flammable alkyl free radical from the decomposed matrix; whereas the flame retardant EG can rapidly expand and form loose and worm‐like expanding graphite char layer accordingly, which can hinder the heat transmission to the inner matrix and reduce decomposing velocity of matrix. After the combination of the two flame retardant effects, the DMMP/EG flame retardant system provides the matrix with better flame retardant effects than one of them does. Namely, it shows excellent gas‐condensed bi‐phase synergistic effect. POLYM. COMPOS., 35:301–309, 2014. © 2013 Society of Plastics Engineers     

Bio-based rigid polyurethane foam composites reinforced with flame retardants: From synthesis to performance evaluation

The building and construction industry is under increasing pressure to make insulation materials greener, more sustainable, and less flammable. In this study, sugar beet pulp was liquified under the optimized liquefaction conditions and used as the source of bio-polyol (SBpol) in the production of bio-based rigid polyurethane foam (sPUF). In order to improve the flame retardancy, sPUF composites were prepared with the addition of flame retardants; expandable graphite (EG) and/or dimethyl methyl phosphonate (DMMP). The bio-polyol was used at a fixed ratio of 50 php in sPUF composites whereas the total ratio of flame retardants was fixed at 20 php. The effects of the ratio of EG and/or DMMP on the morphological, physicomechanical, thermal, and flame retardant properties of sPUF composites were evaluated. Although the thermal conductivity values of flame retardant added sPUF composites were increased in comparison to the petroleum-based foam, the compressive strength values were decreased as the amount of DMMP increased in the flame retardant formulation. Thermogravimetric analysis showed that the onset of decomposition of 20 php DMMP-containing sPUF composite decreased to 168.3°C. Although the limiting oxygen index (LOI) value of the petroleum-based PUF was as low as 19.7%, the LOI value of the sPUF/10E/10D foam increased to 24.9% (by about 26%). According to the cone calorimeter results, the peak heat release rate (pHRR) of sPUF was much higher than the petroleum-based foam. The incorporation of both DMMP and EG could further improve the flame retardant properties. The pHRR value of sPUF/10E/10D was 28.1% lower than that of sPUF. The results have shown that flame retardancy of sPUF composites could be improved by the addition of EG which acts in the condensed phase and DMMP, which acts mainly in the gas phase during burning. Flame retardant incorporated sPUF composites are considered as promising materials for use in insulation applications.     

Improved mechanical,thermal, and flame-resistant properties of polyurethane–imide foams via expandable graphite modification

Although polyurethane–imide (PUI) foams combine the advantages of both polyurethane foam and polyimide foam, the performance of PUI might still not reach certain high-level requirements. Thus, expandable graphite (EG), as a kind of effective reinforcing filler, was introduced into the PUI matrix to improve the physical properties of the foam. Furthermore, to enhance the interfacial compatibility, EG was surface-modified with a silane coupling agent. The experimental results show that the addition of EG was beneficial for enhancing the comprehensive performance of the PUI foams, especially their thermal stability and flame resistance. In particular, the surface-modified, EG-filled PUI foam exhibited outstanding enhancements compared to that with only pristine EG incorporation; not only the compressive strength but also the thermal degradation properties were greatly enhanced by the increased interfacial compatibility between PUI and EG. In addition, the flame-resistant properties were improved by the surface modification of EG. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 46990.     

Mechanical and flame-resistance properties of polyurethane-imide foams with different-sized expandable graphite

Polyurethane-imide (PUI) composite foams with expandable graphite (EG) of different sizes were prepared by a polyimide prepolymer method. EG particles were treated with a silane coupling agent to improve compatibility with the foam. The effect of EG particle size on cell morphology, thermal degradation, flame-resistance and mechanical properties of PUI foams was investigated. Results showed that the mean cellular diameter of foams with EG particle was much higher than that of foams with surface-modified EG particle at the same filler loading. When filler particle diameter increased from 20 to 90 μm, the compressive strength, density and closed-cell ratio of foams increased, and then decreased when filler particle diameter further increased from 90 to 150 μm. Thermal stability of foams increased with the increasing filler particle diameter from 20 to 50 μm, and decreased with the increasing filler particle diameter from 50 to 90 μm. The limited oxygen index (LOI) value of foams with surface-modified EG increased from 24.8% to 32.1% when EG particle diameter was below 90 μm. Foams with surface-modified EG exhibited enhanced mechanical properties, thermal stability and flame resistance than foams with neat EG at the same loading.     

四元复合体系在硬质聚氨酯泡沫材料中的逐级释放阻燃行为研究

以甲基膦酸二甲酯（DMMP）、10-（2,5-二羟基甲苯）-10-氢-9-氧杂-10-磷酰杂菲-10-氧化物（DOPO-HQ）、可膨胀石墨（EG）和氢氧化铝（ATH）构建了四元阻燃复合体系,并通过热失重分析仪（TG）、锥形量热仪、极限氧指数分析仪等研究了其在硬质聚氨酯泡沫（RPUF）中的阻燃行为。结果表明,四元阻燃体系能够在较宽温度区间内发挥逐级释放的协同阻燃效应;DOPO-HQ能够与EG/DMMP/ATH三元阻燃体系形成加合阻燃效应,使得RPUF复合材料的极限氧指数（LOI）提升至30.8%;与采用EG/DMMP/ATH三元阻燃体系的RPUF复合材料相比,采用加入DOPO-HQ的四元阻燃体系的RPUF复合材料的热释放速率峰值（PHRR）、总热释放量（THR）、总烟释放量（TSR）均有所下降,残炭率得到了进一步提升,说明DOPO-HQ与EG/DMMP/ATH所构建的四元阻燃体系在成炭性方面具有协同效应;此外,通过扫描电子显微镜（SEM）对残炭进行表征,验证了四元阻燃体系在凝聚相中能够发挥优异的成炭阻隔效应,并能够在燃烧的初期、中期和末期发挥逐级释放阻燃效应。     

DMMP与EG在RPUF中的阻燃协效研究

利用锥形量热仪研究了可膨胀型石墨(EG)和甲基麟酸二甲酯(DMMP)对硬质聚氨酯泡沫(RPUF)的阻燃协同作用.结果表明,当DMMP/EG质量比为2.5:7.5,RPUF中添加质量分数为10%的该复配阻燃剂时,其热释放速率(HRR)为51.8 kW/m2,热释放峰值(PHRR)为148.67 kW/m2,总烟释放(TS...     

甲基膦酸二甲酯/木质素磺酸钠聚氨酯泡沫的制备及其阻燃性能

利用木质素磺酸钠(SLS)替代部分聚醚多元醇,同时将甲基膦酸二甲酯(DMMP)作为添加型阻燃剂,采用"一步发泡法"制备出甲基膦酸二甲酯/木质素磺酸钠聚氨酯泡沫材料(DMMP/SLS/PUF),通过极限氧指数(LOI)测试对其阻燃性能进行分析,探究了 SLS替代率及DMMP添加量对材料阻燃性能的影响.并利用锥形量热(CO...     

可膨胀石墨阻燃EVA燃烧性能及热失重行为的研究

用粒径为37、48及75μm的可膨胀石墨(EG)阻燃EVA,用锥形量热仪探讨了不同粒径的EG对EVA的阻燃作用,利用热失重分析仪研究了EVA/EG体系的热稳定性。结果表明:经过锥形量热仪测试表明,EVA/EG的热释放速率曲线呈现前单峰型,体现了典型的凝聚相阻燃机理;30 g EG的加入可以明显降低热释放速率,且粒径越大,阻燃效果越好;通过TG考察EG/EVA阻燃体系的热降解行为,在空气气氛下,EG膨胀炭层负载催化EVA交联成炭;相比于75μm EG,48μmEG形成炭层紧密,成炭量超过2.2%,形成的炭层稳定,在850℃也不会分解。