ATH和APP对聚乳酸/竹粉复合材料阻燃抑烟性能的影响

利用竹粉和聚乳酸为原料复合制备聚乳酸/竹粉复合材料,分别采用氢氧化铝(ATH)和聚磷酸铵(APP)阻燃剂对聚乳酸/竹粉复合材料进行阻燃抑烟处理并对阻燃处理后的复合材料进行性能测试。结果表明,两种阻燃剂的加入均使复合材料高温下的成炭率提高了约2倍,分别达到了24.7%和25.6%;ATH和APP的加入均有效提高了聚乳酸/竹粉复合材料的阻燃性能;其中,APP对复合材料燃烧过程中热量释放的抑制明显,其热释放速率在燃烧100s以后下降了近2倍,约为150kW/m2,但生烟量大;而ATH对复合材料的抑热效果不及APP,但抑烟效果显著,平均烟释放速率只有约0.02m2/s。     

聚磷酸铵/Zn-Fe-LDH协效阻燃环氧树脂研究

聚磷酸铵(APP)单独应用于阻燃环氧树脂(EP)时,阻燃效率较低,往往需要较大的添加量才能达到环氧树脂复合材料的阻燃要求。通过制备层状双金属氢氧化物Zn-Fe-LDH,然后将其与聚磷酸铵复配引入环氧树脂中,成功制备出阻燃型复合材料(Zn-Fe-LDH+APP)/EP。极限氧指数(LOI)及垂直燃烧(UL94)测试表明,当Zn-Fe-LDH和APP的总添加量为5%时,(Zn-Fe-LDH+APP)/EP的LOI为28.6%,UL94可达V-1级,锥形量热结果表明,相比较纯APP,Zn-Fe-LDH和APP体系可明显降低环氧树脂的热释放和烟释放。     

海泡石与APP对PVC/竹粉复合材料的阻燃抑烟机理

将海泡石(SEP)和聚磷酸铵(APP)同时加到聚氯乙烯(PVC)/竹粉复合材料中,考察SEP和APP对复合材料的协效阻燃抑烟作用及力学性能的影响。结果表明,在锥形量热实验中,热释放速率峰值相对减少42.8%,平均热释放速率和总热释放量相对减少29.5%和25.7%,总烟释放量相对降低了12.2%,一氧化碳平均产率相对降低了42.0%;扫描电子显微镜分析发现,APP具有催化成炭并形成膨胀泡沫炭层的作用,而SEP具有吸附聚集诱导成炭的作用;APP的阻燃机理主要属于气相阻燃机理,SEP的阻燃机理主要属于凝聚相阻燃机理;弯曲性能测试结果表明,SEP与APP对PVC/竹粉复合材料具有协同颗粒增强作用;拉伸性能测试结果表明,SEP对PVC/竹粉复合材料的塑性变形能力的损害比APP小。因此,SEP与APP联用能够对PVC/竹粉复合材料进行有效的阻燃抑烟,同时也能增强复合材料的力学性能。     

聚磷酸酯膨胀阻燃剂复配有机蒙脱土阻燃改性环氧树脂

以间苯二胺为固化剂,聚苯氧基磷酸210氢9氧杂磷杂菲对苯二酚酯（POPP）、聚磷酸铵（APP）为阻燃剂, 复配质量分数为1 %有机蒙脱土（OMMT）为膨胀阻燃体系,对环氧树脂（EP）进行阻燃改性。通过极限氧指数测定仪、垂直燃烧测定仪同步热分析仪、锥形量热等研究改性EP的阻燃性能、热性能和力学性能。结果表明,当膨胀阻燃体系（2.5 %POPP/APP+1 %OMMT）添加量为3.5 %时,改性EP可达UL 94 V-0级,同时LOI为25.2 %;当膨胀阻燃体系添加量为11 %时,改性EP的LOI值进一步升高到31.7 %;阻燃剂的加入,使EP的初始分解温度略有降低,但残炭量明显增加;POPP/APP/OMMT的加入很大程度上降低了EP的热释放速率、烟释放量和平均热释放速率。     

膨胀石墨(EG)协同新型磷系膨胀阻燃环氧树脂的制备及阻燃性能研究

经六(4-DOPO羟甲基苯氧基)环三磷腈(DOPOMPC)和聚磷酸铵(APP)处理环氧树脂(EP)的基础上加入可膨胀石墨(EG),制备新型膨胀阻燃环氧树脂复合材料(DOPOMPC/APP/EG/EP)。通过极限氧指数(LOI)、水平垂直燃烧(UL-94)、锥形量热(CONE)、扫描电镜(SEM)等方法,研究了协效剂EG加入对复合材料阻燃性能和力学性能的影响。结果表明,适量EG与DOPOMPC/APP体系有良好的协同阻燃作用,并提高了环氧树脂复合材料力学性能。当DOPOMPC/APP/EG总添加量为22%(DOPOMPC/APP/EG的比例为5/5/1),复合材料LOI值高达38.4%;热释放速率峰值(pk-HRR)、比消光面积(av-SEA)、有效燃烧热平均值(av-EHC)和一氧化碳释放率平均值(av-CO)较纯EP(EP0)分别降低了81.8%,35.5%、29.0%和33.3%;其拉伸强度、弯曲强度和冲击强度比EP1(10%DOPOMPC/10%APP/EP)体系分别提高了70.5%、1.5倍和2.6倍。     

基于CONE试验方法的P-N阻燃环氧树脂复合材料燃烧性能研究

设计合成的新型磷氮系阻燃剂双酚A-双(5,5-二溴甲基-1,3-二氧杂己内磷酸酯)(FR)与聚磷酸铵(APP)配比为2:1时,利用锥形量热仪(CONE)测试其释热速率(HRR)、释热总量(THR)、质量损失速率(MLR)、生烟量(TSP)及有毒气体释放量等多种燃烧性能参数;实验结果表明,当复合材料中阻燃体系配比为13.3%FR:6.7%APP时,阻燃EP与纯EP相比HRR,THR,MLR及SEA等参数下降程度最大,P-N阻燃复合材料具有优良的成碳率、良好的阻燃效果和抑烟性能。     

卡拉胶/金属氧化物协同聚磷酸铵制备阻燃天然橡胶

将卡拉胶(KC)、聚磷酸铵(APP)分别和Fe2O3、CuO、Al2O3、MnO24种金属氧化物(MO)三者复配构成的协同阻燃剂(KC/MO/APP)加入到天然橡胶(NR)中,制备了NR/KC/MO/APP复合材料.通过极限氧指数(LOI)、垂直燃烧(UL-94)、锥形量热(CCT)测试了其阻燃性能.结果表明,NR/KC/MO/APP复合材料的阻燃等级均达到UL-94 V-0级,LOI在26.5％～27.3％之间,具有较好的阻燃性.与NR相比,NR/KC/CuO/APP复合材料的热释放速率峰值和总热释放量分别下降了63.7％和42.0％.同时KC/MO/APP还有抑烟作用,NR/KC/Fe2O3/APP复合材料总烟释放量比NR下降了35.0％,处于最低水平.TGA结果显示,NR/KC/CuO/APP复合材料800℃时的残炭量(W800)达到34.85％,比NR/APP提高了28.7％.NR/KC/MO/APP复合材料炭层更致密,表明KC/MO与APP的协同作用对形成稳定炭层起着重要作用.另外,NR/KC/MnO2/APP复合材料力学性能最优,其拉伸强度和断裂伸长率比NR/APP分别提高32.6％和20.9％,表明MnO2的加入可弥补阻燃剂对NR造成的力学性能损失.     

壳聚糖/聚磷酸铵膨胀阻燃PP的阻燃及抑烟性能

为了提高聚丙烯(PP)的阻燃和抑烟性能,将壳聚糖(CS)作为膨胀型阻燃剂的碳源、聚磷酸铵(APP)作为膨胀型阻燃剂的酸源和气源,在此基础上通过熔融共混的方法制备了PP/CS/APP复合材料。采用极限氧指数仪、锥形量热仪等仪器研究了PP/CS/APP复合材料的的抑烟性及阻燃性。研究结果表明:CS/APP添加量为30%时,复合材料的极限氧指数值最大可达28.1%;且复合材料在烟气释放总量、CO和CO_2排放上明显降低,抑烟性得到了提升;热释放速率峰值、平均热释放速率值、平均有效燃烧热值、总热释放量值降低,成炭率升高,PP/CS/APP复合材料更难点燃;火灾性能指数明显提高,阻燃性能得到了大幅度提升,火灾蔓延指数显著减小,同时火灾危险性也相应降低。     

卡拉胶包覆APP/MnO2增强水性环氧树脂阻燃抑烟性能

用反相乳液法，以卡拉胶（KC）为壳材，聚磷酸铵（APP）和二氧化锰（MnO2）为芯材，制备了KC包覆APP/MnO2阻燃剂（KC-FR）。通过FTIR、 XRD、 SEM和 EDS对KC-FR进行了表征。结果表明：卡拉胶已成功包覆APP和MnO2，合成的样品具有微胶囊结构。将KC-FR应用于水性环氧树脂（EP）中，考察KC、APP、MnO2 三者质量比对EP阻燃、抑烟性能的影响。用极限氧指数（LOI）、垂直燃烧（UL-94）和锥形量热（CCT）测试了涂层的阻燃、抑烟性能。结果发现，当KC/APP/MnO2的质量比为2∶1∶1，并且在EP中添加量为20%时，制备的阻燃涂层EP2的LOI达到29.1%，UL-94达到V-0级，表现出较好的阻燃性能。EP2相比于其它涂层热释放峰值（pHRR）、热释放总量（THR）和烟释放总量（TSP）最低，相比于EP0分别下降了42%、37%和46%，表现出较好的抑烟性能。另外，热重分析（TGA）测试结果显示EP2在800℃残炭量（W800）为33%，表明KC-FR具有促进EP成炭的功能。通过SEM对残炭表面分析发现，EP2表面炭层更加致密，这表明KC-FR对促进形成稳定并且致密的炭层起到至关重要的作用。     

新型磷系阻燃剂阻燃环氧树脂的应用研究

以新戊二醇、三氯氧磷、1,2,3-三羟基苯为原料合成新型磷系阻燃剂1,2,3－三(5,5－二甲基－1,3－二氧杂己内磷酰氧基)苯(FR),将FR与环氧树脂(EP)熔融混合制备阻燃EP/FR复合材料。采用极限氧指数测试、垂直燃烧实验、热重分析、锥形量热分析、扫描电镜研究了FR对EP的阻燃性能和阻燃机理。结果表明,添加20 % FR的EP/FR复合材料的极限氧指数达到27.8 %,垂直燃烧通过UL94 V-0级,热释放速率平均值和生烟量平均值比未阻燃EP分别降低了77.0 %和82.8 %,扫描电镜分析表明, EP/FR体系燃烧后能形成连续、致密、封闭的焦化炭层。     

Preparation of DOPO-derived magnesium phosphate whisker and its synergistic effect with ammonium polyphosphate on the flame retardancy and mechanical property of epoxy resin

In this study, a magnesium phosphate whisker (DPM-H) was synthesized by the acid–base neutralization reaction between magnesium hydroxide and 10-hydroxy-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO-OH) at 120°C. A new synergistic intumescent flame retardant (IFR) for epoxy resin (EP), which was composed of DPM-H and ammonium polyphosphate (APP) was thoroughly studied. When the IFR loading was 8%, with the DPM-H to APP weight ratio at 1:7, the prepared flame-retardant EP (EPDA-2) passed the vertical burning tests (UL-94) V-0 rating and obtained the limiting oxygen index (LOI) value of 29.3%. Microscale combustion calorimetry (MCC) results showed that the total heat release (THR) of EPDA-2 reduced by 32.1% compared with pure EP. Meanwhile, the addition of DPM-H can partially solve the problem of the decrease of the EP mechanical property caused by the addition of APP. Compared with the flame-retardant EP with the 8% loading of APP, the impact strength of EPDA-2 increased 152.3%.     

Excellent role of Cu2O on fire safety of epoxy resin with ammonium polyphosphate based on the construction of self-intumescent flame retardant system

This work reports an effective self-intumescent flame retardant system for epoxy resin (EP) based on the remarkable synergistic effect between Cu₂O and ammonium polyphosphate (APP). The effect of Cu₂O/APP on improving EP's fire performance was evaluated by limited oxygen index (LOI), UL-94, and cone calorimeter test. The optimal mass ratio of Cu₂O: APP was shown to be 2:8. With 15 wt% total flame retardant loading, the EP with optimum Cu₂O/APP formulation reached V-0 classification and high LOI (33.5%), while the EP with APP only got NR and low LOI (26.5%). Additionally, the pHRR, total heat release, total smoke production, CO production of the EP with optimum Cu₂O/APP formulation were primarily decreased. All the improvements were ascribed to the formation of the self-intumescent char layer of EP resulted from the catalyzing effect of Cu₂O for char formation and CO to CO₂ conversion. These findings will consolidate approaches for conferring flame retardancy to flammable polymers or their blends.     

蜜胺-环氧树脂双层包覆聚磷酸铵及其阻燃PP的研究

针对聚磷酸铵(APP)耐水性不足、与聚丙烯(PP)等高分子材料相容性差等问题，采用甲醛-三聚氰胺(蜜胺树脂)和环氧树脂双层包覆了APP(EM-APP)，采用红外、扫描电镜、热重分析、溶解度测试等方式表征了包覆效果；采用水平垂直燃烧、氧指数仪和锥形量热仪、热重-红外联用等设备考察了包覆APP用于阻燃PP的效果，探讨了阻燃机理。结果表明：包覆操作不但有效提高了APP的耐水性，且将具有成炭功能的包覆层引入到APP表面；EM-APP相较APP，800℃时残炭量提高14.2%，在聚丙烯中加入同样质量份时，前者具有更高的阻燃效率，热释放速率、总热释放量、烟释放速率和总烟释放量都明显降低；包覆改善了APP与PP的相容性；燃烧过程中包覆层起到了协同成炭的作用。     

三聚氰胺包覆聚磷酸铵阻燃环氧树脂的研究

研究了三聚氰胺包覆聚磷酸铵(MPP)与季戊四醇(PER)阻燃环氧树脂的燃烧性能。通过热重分析初步探讨了MPP/PER阻燃剂对环氧树脂的阻燃机理。结果表明:MPP/PER对环氧树脂具有很好的阻燃作用,能有效提高环氧树脂的氧指数和垂直燃烧性能,降低环氧树脂的热释放速率,使燃烧过程变得稳定,降低环氧树脂的火灾危险性。热重分析表明:添加了阻燃剂以后,环氧树脂的初始分解温度降低,残炭量显著增加,阻燃剂发挥了凝聚相阻燃的作用。     

Flame retardant and mechanical properties of epoxy composites with ammonium polyphosphate and hyperbranched silicon-containing polymers

The epoxy resin was mixed with ammonium polyphosphate (APP) and hyperbranched silicon-containing polymers (HBP-B2). The cured composites were investigated by thermogravimetric analysis, Underwriters Laboratory standard for the flammability properties under vertical burning (UL-94V), and limited oxygen index (LOI) test methods. The LOI of 43.5 and could be obtained at the weight ratio of 70:25:5 for the epoxy resin:APP:HBP-B2, Sample A25B5, and the LOI was higher than that of the composite with 30 wt % APP only, Sample A30B0, of which the LOI was 34.5. It suggested that the HBP-B2 could cooperate with the epoxy/APP composite to form a more effective protection layer during combustion, which resulted in a higher second-stage thermal degradation temperature. During the UL-94V test, the flame was extinguished immediately once the burner was removed. Furthermore, the tensile and impact strength of the epoxy/APP composite could also be improved by using HBP-B2 compound as the toughening agent. The composite containing 20% of APP and 10% of HBP-B2, Sample A20B10, still had excellent flame retardant properties with a V-0 rating. Moreover, the tensile strength and impact strength of that composite got 19 and 25% increases compared with the Sample A30B0, which contained 30% of APP only. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48857.     

Synergistic action of expandable graphite on fire safety of a self-intumescent flame retardant epoxy resin

Previously, it was reported that epoxy resin (EP) filled with ammonium polyphosphate (APP) and copper (I) oxide (Cu₂O) at a mass ratio of 8/2 (APP8-Cu₂O2) as a self-intumescent system demonstrated promising fire retardancy. To further improve the flame retardant efficiency, the possibility of expandable graphite (EG) as an effective synergist for the self-intumescent EP system was revealed by limiting oxygen index (LOI) test. The results showed that the incorporation of EG increased the LOI value of EP/APP8-Cu₂O2 obviously. The highest LOI value was obtained at the EG/APP8-Cu₂O2 mass ratio of 3/7, indicating the optimal synergistic effect being achieved. Furthermore, UL-94 test results showed that the excellent synergistic effect resulted in the addition of 13 wt% EG/APP8-Cu₂O2 of 3/7 not only endowed EP a relatively high LOI value of 34.3%, but also made it pass UL-94 V-0 rating. Moreover, the main fire hazard parameters obtained from cone calorimeter tests, such as peak heat release rate, total smoke production, and peak CO production were reduced 40.3%, 30.3%, and 46.2%, respectively by the combination effect of EG/APP8-Cu₂O2 with mass ratio of 3/7, suggesting the excellent improvement in the fire safety of EP significantly. Finally, a possible action mode, which would be beneficial for developing other flame retardant polymers with high fire safety, was proposed.     

Loading the polyol carbonization agent into clay nanotubes for the preparation of environmentally stable UV‐cured epoxy materials

The halloysite nanotubes (HNTs) were loaded with pentaerythritol (PER). The as‐prepared composite (HNT‐P) and ammonium polyphosphate (APP) was subsequently added to the UV‐curable epoxy resins, giving a new flame‐resistant system. Loading of the hydrophilic PER into HNT can reduce the moisture absorption in the UV‐curable epoxy resins. The flame retardancy was evaluated by means of the cone calorimeter and limit oxygen index test. The results showed that the flame retardancy of the modified epoxy resin was greatly improved with an obvious decrease in both the heat release and smoke release. Moreover, it was revealed that HNT could catalyze the reaction of APP and PER, and the burning surface of the epoxy resin should be covered by the polyphosphoric‐HNT intumescent char layer. We have measured the moisture sorption and dynamic mechanical properties of the UV‐cured epoxy resins. As compared to the use of the simple mixture of PER and HNT, the use of the HNT‐P nearly kept the storage modulus at about 1809 Mpa and reduced the moisture absorption by 58.2 wt % at 40 °C. The results proved that the addition of the HNT‐P obtained lower moisture absorption and higher stability of the mechanical properties than adding the simple mixture. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45045.     

环氧树脂含量对氰酸酯热学性能的影响研究

采用示差扫描量热法(DSC)和热失重分析法(TGA)研究了环氧树脂含量对氰酸酯树脂固化反应特性、热稳定性以及热膨胀系数的影响。结果表明,环氧树脂的加入可有效降低改性体系的固化反应活化能,同时体系的热稳定性和尺寸稳定性有不同程度的削弱。当环氧树脂质量分数达到20%时,改性体系的表观活化能为65.4 kJ/mol,耐热温度指数为174℃,较纯氰酸酯树脂分别降低了25.8%和21.4%。当环氧树脂质量分数达到50%时,改性体系的热膨胀系数为65.3 922×10-6/℃(25～150℃),较纯氰酸酯树脂提高了8.13%。     

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。