六苯氧基环三磷腈阻燃PC/ABS合金及其高性能化研究

采用熔融挤出法制备了阻燃聚碳酸酯/丙烯腈丁二烯苯乙烯共聚物（PC/ABS）合金材料。利用热失重分析仪、氧指数测试仪、垂直燃烧仪、锥形量热仪、电子万能试验机和冲击试验机研究了相容剂马来酸酐接枝聚乙烯共聚物（PE-g-MAH）以及阻燃剂六苯氧基环三磷腈（HPCTP）的加入对PC/ABS合金材料的热稳定性、阻燃性能和力学性能的影响,并采用扫描电子显微镜对材料的残炭形貌进行分析。结果表明,当PC/ABS的质量比为7/3,以PE-g-MAH为相容剂,且HPCTP添加量为15 %时,阻燃PC/ABS合金材料的综合性能最好,其极限氧指数为26.4 %,热释放速率峰值及热释放总量达到最小值,且能够达到UL 94 V-0级,拉伸强度和缺口冲击强度分别为55 MPa和32.9 kJ/m2。     

HPCTP/MMT复配阻燃环氧树脂阻燃及力学性能研究

将六苯氧基环三磷腈(HPCTP)与蒙脱土(MMT)复配,并以之为阻燃剂制备了阻燃环氧树脂。采用锥形量热仪对阻燃环氧树脂进行了燃烧测试,并对热释放速率、烟释放速率等数据进行了分析。结果表明,两种阻燃剂具有较好的协同阻燃效果,其中当MMT用量为1份时,热释放速率峰值(pk-HRR)下降了39.2%。力学测试表明,HPCTP的引入可以提升环氧树脂的拉伸性能,而同时加入1份的MMT可使体系的拉伸性能达到最佳,添加过量的MMT则会导致体系力学性能下降。     

硅氧烷处理纳米层状硅酸盐对膨胀阻燃聚乳酸性能的影响

采用4种经过不同表面处理剂改性的有机层状硅酸盐（Clay）与膨胀型阻燃剂复配阻燃聚乳酸（PLA）。通过熔融共混的方法制备阻燃PLA纳米复合材料,并通过极限氧指数、垂直燃烧、锥形量热测试和热失重分析对材料阻燃性能和热稳定性进行了研究,通过扫描电子显微镜对残炭形貌进行了分析。结果表明,加入经硅氧烷表面处理的Clay的PLA具有最好的热稳定性和阻燃性能;与不加Clay的阻燃PLA复合材料相比,极限氧指数从30.6 %提高至34.2 %,并且通过垂直燃烧UL 94 V-0级别,热释放速率峰值从283 kW/m2下降至199 kW/m2,下降幅度为30 %;残炭形貌分析结果显示,加入硅氧烷表面处理之后的Clay能够使残炭更加完整致密,从而提高了材料的阻燃性能。     

PP/MPP/PEPA的制备及其热降解性能研究

采用多聚磷酸蜜胺(MPP)和笼状季戊四醇磷酸酯(PEPA)复配阻燃剂,制备了具有良好阻燃性能的膨胀阻燃聚丙烯(PP),研究了各组分质量比对PP阻燃性和热降解性能的影响.结果表明:MPP与PEPA质量比为3:2时,阻燃复配效果最好;且添加阻燃剂质量分数为20%时,极限氧指数达到27%,UL达到Ⅴ-0级;热失重分析结果表明,MPP/PEPA可以延缓PP的分解;利用Kissinger法求取了材料的活化能,发现添加阻燃剂后,材料的活化能提高;残留物的红外光谱分析结果表明,MPP复配PEPA后,保留了更多的PP特征峰;体视显微镜和扫描电镜分析表明,添加阻燃剂后,材料形成了膨胀炭层,提高了 PP阻燃性能.     

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。     

磷–氮膨胀型阻燃剂复配协同阻燃聚甲醛的研究

采用磷–氮复配膨胀型阻燃剂(50A)与酚醛树脂(PF)进行复配,研究了不同配比对聚甲醛(POM)的阻燃性能和力学性能的影响。通过垂直燃烧试验、极限氧指数法、热重分析研究了复配阻燃剂对POM的阻燃作用,并对阻燃POM材料燃烧后的残炭进行红外分析。结果表明,采用50A/PF复配的阻燃POM材料的垂直燃烧级别达到UL94 V–1级,极限氧指数可达26.7%;热重分析显示,阻燃POM材料在800℃时的残炭率显著提高;红外光谱分析证实了50A与PF在POM中有良好的协效阻燃作用。     

PM/PEPA协同阻燃硬质聚氨酯泡沫塑料的性能研究

将磷酸三聚氰胺盐(PM)和季戊四醇磷酸酯(PEPA)复配成一种新型的无卤阻燃剂,并对硬质聚氨酯泡沫(RPUF)塑料进行阻燃。利用极限氧指数(LOI)和热重分析(TGA)考察了阻燃RPUF的阻燃性能及热降解行为,采用残炭率和燃烧试验对阻燃RPUF进行测试分析。结果表明,PM和PEPA按质量比为1∶1复配而成的阻燃剂对RPUF塑料阻燃时效果优异,在阻燃剂添加量为16%时,RPUF氧指数达到24.3%左右,500℃时残炭率为37.4%。PM和PEPA复配能使RPUF高温燃烧时形成较稳定的炭层,对RPUF塑料具有阻燃协同作用。     

HHPCP与DMMP复配阻燃聚氨酯硬泡的研究

以六(对羟甲基苯氧基)环三磷腈(HHPCP)与甲基磷酸二甲酯(DMMP)组成复配阻燃剂制备了阻燃聚氨酯硬泡。利用FT-IR研究了HHPCP与多亚甲基多苯基多异氰酸酯(PAPI)的交联反应,通过扫描电子显微镜、极限氧指数测试仪、热重分析仪以及微型量热仪研究了HHPCP/DMMP不同配比对聚氨酯硬泡的阻燃性能和热性能的影响。结果表明,当在50份聚醚多元醇中加入阻燃剂HHPCP与DMMP各10份时,阻燃聚氨酯硬泡的氧指数、抗压强度、密度达到最优,氧指数为24.5%,且总释放热由21.6 k J/g降低到16.9 k J/g。     

磷系阻燃剂FR/APP协效阻燃PP

采用氧指数测定仪、热重分析仪和锥形量热仪研究了磷系阻燃剂1,3,5-三(5,5-二甲基-1,3-二氧杂环己内磷酸基)苯(FR)和聚磷酸铵(APP)复配体系对聚丙烯(PP)材料阻燃性能的影响.结果表明,FR/APP提高了PP的极限氧指数(LOI)、热稳定性和残炭率,降低了热释放速率.当w(FR)为15%和w(APP)为10%复配阻燃PP时,复合材料的LOI为29.6%.阻燃级别达到UL 94 V-0级.     

KH550改性PEPA对PP/IFR体系阻燃、耐水和力学性能的影响

利用硅烷偶联剂KH550对季戊四醇磷酸酯(PEPA)进行表面改性,得到Si-PEPA,将其与三聚氰胺聚磷酸盐(MPP)复配成膨胀型阻燃剂(IFR)对聚丙烯(PP)进行阻燃改性。研究了KH550改性PEPA对PP/IFR体系阻燃、耐水和力学性能的影响。利用极限氧指数(LOI)仪、垂直燃烧(UL94)仪、锥形量热(CONE)仪对阻燃PP的燃烧性能进行测试,结果表明,当IFR的添加量为20%时,PP/MPP/Si-PEPA体系可以达到UL94 V-0级,氧指数达到32.5%,最大热释放速率(PHRR)和总热释放量(THR)都较PP/MPP/PEPA体系有明显降低。热重分析(TGA)显示,经KH550处理后,PP/IFR材料的热稳定性显著提高。经70℃热水浸泡72 h后,PP/MPP/Si-PEPA材料仍然可以通过UL94 V-1级。同时,KH550对PEPA的表面处理也提高了PP/IFR材料的力学强度。     

Synthesis of a novel flame retardant containing phosphazene and triazine groups and its enhanced charring effect in poly(lactic acid) resin

A novel flame retardant heax‐[N,N′,N″‐tris‐(2‐amino‐ethyl)‐[1,3,5] triazine‐2,4,6‐triamine] cyclotriphosphazene (HTTCP) containing phosphazene and triazine groups was synthesized and characterized by Fourier transform infrared spectroscopy (FTIR), solid‐state ¹H and ¹³C nuclear magnetic resonance (NMR) spectroscopy. HTTCP was applied to PLA matrix. The results of thermal gravimetric analysis (TGA), the limited oxygen index (LOI), and cone calorimeter test indicated that the HTTCP enhanced the thermal stability and flame retardant properties of PLA. When the mass fraction of HTTCP was 25 wt %, the PLA composite acquired a LOI value of 25.2% and the lower pk‐HRR at 290 kW/m². The excellent flame retardancy of HTTCP was attributed to the group synergistic effect between phosphazene and triazine groups. However, when combined HTTCP with APP (the total amount remaining 25 wt %, the ratio of HTTP to APP are 1:1 and 1:2), high values of LOI (over 40%) and UL94 V‐0 rating without dripping reached simultaneously. Meanwhile, the heat release rate, total heat release and mass loss rate were all decreased dramatically. Scanning electron microscopy (SEM) demonstrated that HTTCP/APP system benefited to the formation of more intumescent, dense, compact char layer on the materials surface which could effectively prevent the underlying material from degradation during burning. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44660.     

A novel bio-based charcoal-forming agent based on chitosan and phytate@Mg to improve the flame retardancy of poly(lactic acid)

A novel bio-based carbon forming agent (Mg@PA-CS) containing P and N elements was were synthesized using the complexation characteristics of chitosan (CS) and phytate (PA). The flame retardant behavior of poly(lactic acid) (PLA)/Mg@PA-CS/APP composites (addition of 20 wt% of different ratios of Mg@PA-CS and APP to polylactic acid composites) were investigated by the limiting oxygen index (LOI), vertical burning test (UL-94), cone calorimetry test (CCT), and thermogravimetric analysis (TGA). Due to the biphasic flame retardant and synergistic effect, since the 20 wt% flame retardant system (Mg@PA-CS:APP = 1:2), PLA composites passed the UL-94 test V-0 rating, reached 34% LOI value. The peak heat release rate (PHRR) and total heat release rate (THR) were reduced to 1/2 of the pure PLA, char residue could be as high as 11.49% at 800°C. Moreover, the flame-retardant mechanism of PLA composites during thermal decomposition was analyzed using a scanning electron microscope (SEM) and the coupling techniques of TGA linked with FT-IR (TG-FTIR).     

Mechanical,thermal and combustion properties of intumescent flame retardant biodegradable poly (lactic acid) composites

ABSTRACT

Despite extraordinary mechanical properties and excellent biodegradability, poly (lactic acid) (PLA) still suffers from a highly inherent flammability, restricting its applications in the electric and automobile fields. Although a wide range of flame retardants have been developed to reduce the flammability, they normally compromise the mechanical strength of PLA. In this study, a series of composites based on PLA, have been prepared by melt-blending with intumescent flame retardants (IFRs). The morphology, thermal stability and burning behaviour of the composites were investigated using a scanning electron microscope–energy dispersive spectrometer (SEM–EDS), thermogravimetric analysis (TGA), the limiting oxygen index (LOI), vertical burning (UL-94) and the cone calorimeter test (CCT). The LOI value reached 38.5% and UL-94 could pass V-0 for the PLA/IFR composite containing only 12 wt-% IFR. The dispersion of IFR in PLA was observed using SEM–EDS. A significant improvement in fire retardant performance was observed for the PLA/IFR composite from the CCT (reducing the heat release rate and the total heat release). More importantly, compared to pure PLA, the addition of IFR did not seriously deteriorate the mechanical properties of the material.     

Inorganic/organic phosphorus-based flame retardants synergistic flame retardant rigid polyurethane foam

The flame-retardant rigid polyurethane foam (RPUF) composites are fabricated by ammonium polyphosphate (APP) with pentaerythritol phosphate (PEPA), phenoxycycloposphazene (PCP), and aluminum diethylphosphinate (ADP), respectively, which are labeled as RPUF-1, RPUF-2, and RPUF-3. The influence of flame retardants on the apparent density and compressive strength of RPUF is studied. The results reveal that flame retardants not only improve the apparent density, but also improve the compressive strength of RPUF composites. The limiting oxygen index (LOI) results reveal that these inorganic/organic phosphorus-based flame retardants improve the LOI significantly, especially for RPUF-2 and RPUF-3 systems. The cone calorimeter test results suggest that the peak of heat release of RPUF-1, RPUF-2, and RPUF-3 systems decrease by 38%, 41%, and 52% likened to that of pure RPUF. And APP and ADP system performs best in declining the heat release. And APP and PEPA systems perform best in decreasing the smoke release. The flame retardancy mechanism of RPUF composites is analyzed in details.     

A novel lanthanum-based phosphorus-containing flame retardant agent and its application in polylactic acid

Currently, intumescent flame retardants (IFR) are often used in the flame retardant modification of polylactic acid (PLA). Due to the high loading, it will weaken the mechanical properties of PLA. In this study, lamellar lanthanum-based DOPO derivative (La@DDP) is prepared by solution method, and it acts as a flame retardant agent was added into PLA with IFR. The results show that PLA composite passes the UL94 V-0 rating with a limiting oxygen index (LOI) of 32.0, in the addition of 4.5 wt% IFR and 1.5 wt% La@DDP. Moreover, the peak heat release rate (PHRR) and total heat release (THR) of the PLA composite reduces by 31.0% and 23.2% compared to pure PLA, respectively. IFR/La@DDP agents assign the PLA composite with excellent thermal stability and carbon-forming ability. Through the analysis of residual char, the synergistic flame retardant mechanism between IFR and La@DDP in PLA composite is discussed. Notably, the tensile strength and elongation at break of the PLA composites are only reduced by 4.03% and 9.51% compared to pure PLA. This work provides a novel lanthanum-based flame retardant agent for designing PLA composites with good fire safety and mechanical properties, and it will broaden the application range of PLA.     

聚乳酸/苯基次膦酸铝复合材料的制备及其阻燃性能研究

采用共沉淀法制备了苯基次膦酸铝(AlP)并对其进行表征。在此基础上,通过熔融共混法制备了一系列聚乳酸/苯基次膦酸铝（PLA/AlP）复合材料,采用热重分析（TG）、极限氧指数测试（LOI）、UL 94垂直燃烧测试、微型量热测试研究AlP对复合材料热稳定性、阻燃性能、燃烧性能的影响。结果表明,AlP可以有效提高PLA/AlP复合材料的阻燃性能, 当AlP含量为30 %（质量分数,下同）时,PLA/AlP30的极限氧指数达到25.6 %,并达到UL 94 为V-0级;AlP可以提高PLA/AlP复合材料初始分解温度和成炭性; PLA/AlP复合材料的热释放速率峰值和总热释放随着AlP添加量增大呈现先增高再下降的趋势。     

Effects of ammonium polyphosphate and triphenyl phosphate on the flame retardancy,thermal, and mechanical properties of glass fiber–reinforced PLA/PC composites

The purpose of this study is to increase of the flammability properties of the glass fiber (GF)–reinforced poly (lactic acid)/polycarbonate (PLA/PC) composites. Ammonium polyphosphate (APP) and triphenyl phosphate (TPP) were used as flame retardants that are including the organic phosphor to increase flame retardancy of GF‐reinforced composites. APP, TPP, and APP‐TPP mixture flame retardant including composites were prepared by using extrusion and injection molding methods. The properties of the composites were determined by the tensile test, limiting oxygen index (LOI), differential scanning calorimetry (DSC), and heat release rate (HRR) test. The minimum T_g value was observed for the TPP including PLA/PC composites in DSC analysis. The highest tensile strength was observed in GF‐reinforced PLA/PC composites. In the LOI test, GF including composite was burned with the lowest concentration of oxygen, and burning time was the longest of this composite. However, the shortest burning time was obtained by using the mixture flame retardant system. The flame retardancy properties of GF‐reinforced PLA/PC composite was improved by using mixture flame retardant. When analyzed the results of HRR, time to ignition (TTI), and mass loss rate together, the best value was obtained for the composite including APP.     

Development of ductile green flame retardant poly(lactic acid) composites using hydromagnesite&huntite and bio-based plasticizer

Turning brittle poly(lactic acid) (PLA) to ductile form via plasticizer inclusion is an effective option in the case of processing with high amounts of additives. Additionally, the integration of natural flame retardants to PLA involving bio-based plasticizer enables to use of environmentally friendly composites in conditions where fire resistance performance is required. In the current study, ductile green fire retardant PLA composites were manufactured using hydromagnesite&huntite (HH) as a natural fire retardant additive and acetyl tributyl citrate as a bio-based plasticizer. The influences of plasticizer and HH contents on the fire retardant, thermal and mechanical performances of the composites were explored. According to test results, the limiting oxygen index (LOI) value of PLA reduced from 29.2 to 28.0 and the UL-94 V rating changed from V2 to BC with the addition of 20 wt% plasticizer owing to the reduction in melt viscosity. The peak heat release rate (pHRR) and average heat release rate (avHRR) values increased steadily as the concentration of plasticizer increased due to the formation of a more porous residue structure stemming from the increased transportation rate of gases. In order to produce ductile flame retardant material, the plasticizer content was required to 20 wt% of HH. The highest LOI value (36.2) and UL-94 rating of V0 were achieved with the inclusion of 70 wt% HH in the presence of 20 wt% plasticizer. Improvement in impact resistance and reduction in tensile strength were observed as the added amount of plasticizer increased.     

ZnO对PP/MPP/PEPA膨胀阻燃体系的协同作用

以ZnO为阻燃协效剂,采用多聚磷酸蜜胺(MPP)和笼状季戊四醇磷酸酯(PEPA)复配阻燃剂,制备了具有良好阻燃性能的无卤阻燃PP。研究了ZnO用量对PP阻燃性能和协效作用的影响。结果表明:添加少量的ZnO即可显著提高PP的阻燃性能。当MPP、PEPA和ZnO添加量分别为12%、8%和1%时,阻燃PP的氧指数高达29.5%。TGA、FTIR分析和体式显微镜观测结果表明:添加ZnO可以催化MPP/PEPA间的酯化反应,促进体系成炭,形成更致密的炭层,从而提高材料的阻燃性能。