阻燃剂对热固性酚醛树脂阻燃性能影响的研究

通过氧指数、垂直燃烧等级及产烟率测定研究了氢氧化铝(ATH)、氢氧化镁(MH)、膨胀石墨(EG)、膨胀型阻燃剂(IFR)等以单一或协同复配的形式对酚醛树脂(PF)体系阻燃性能的影响,并采用差热分析(DTA)对体系的微观热行为进行了研究。结果表明,放热量最小的体系为ATH/MH/EG/PF,ATH/MH/EG/IFR/PF体系的氧指数最大,达到96。ATH/MH/PF体系的产烟率最低(72%)。添加阻燃剂后,体系的垂直燃烧等级可提高到UL94V-0级。     

PP/APP/磷系阻燃剂FR复合材料的燃烧性能研究

将新型磷系阻燃剂1,3,5-三(5,5-二甲基-1,3-二氧杂环己内磷酸基)苯(FR)、无规聚丙烯(APP)加入聚丙烯(PP)中制备了 PP/APP/FR 复合材料,采用极限氧指数测定、垂直燃烧实验(UL94)、锥形量热分析对复合材料燃烧性能进行了研究。结果表明,APP/FR 提高了 PP 复合材料的氧指数和垂直燃烧性能级别,延长了点燃时间,降低了热释放速率和燃烧烟气中的 CO、CO_2浓度,阻燃效果显著。当15%(质量分数,下同)FR 和10%APP 复配阻燃 PP 时,复合材料的氧指数达29.6%,UL94 V-0级。     

新型磷-氮膨胀阻燃剂在改性聚丙烯中的应用研究

采用自制干法合成的磷-氮膨胀型阻燃剂(磷酸酯三聚氰胺盐,IFR)复配聚磷酸胺(APP)和聚四氟乙烯(PT-FE)阻燃改性聚丙烯(PP),利用极限氧指数法、垂直燃烧法分析了阻燃PP的燃烧性能,通过热重分析仪、傅里叶变换红外光谱仪、扫描电子显微镜和X射线光电子能谱对阻燃PP的热降解过程、燃烧性能、残炭结构进行了分析,并研究了燃烧过程中复配阻燃体系对PP的阻燃机理。结果发现,IFR、APP和PTFE之间具有明显的阻燃协效作用;当阻燃剂总添加量为24%(APP为6%、IFR为17.5%、PTFE为0.5%)(质量分数)时,阻燃PP的极限氧指数达到30.1%,垂直燃烧测试达UL 94V-0级;加入阻燃剂还能提高PP的热稳定性。     

改性钠基膨润土协同卤锑阻燃LDPE的研究

采用钠基膨润土(Na-MMT)、卤锑复配阻燃剂和低密度聚乙烯(LDPE)树脂制备了阻燃复合材料,研究了改性Na-MMT协同卤锑复配阻燃剂对LDPE阻燃材料的燃烧性能、力学性能及热性能的影响。结果表明:改性Na-MMT替代部分卤锑复配阻燃剂时,其垂直燃烧等级均达到UL94 V-0级,极限氧指数均在32.0%以上。当改性Na-MMT质量分数为8%时,阻燃材料的极限氧指数达到33.8%;当改性Na-MMT质量分数为16%时,阻燃材料的力学性能最优。     

阻燃PUR-T/PVC合金的制备

利用低成本聚氯乙烯(PVC)作为分散相、高韧性热塑性聚氨酯(PUR-T)作为连续相,以熔融共混方法制备出PUR-T/PVC合金,经过实验对比与配方优化,制备出的PUR-T/PVC合金具有低成本、较高的拉伸强度与韧性、较广的硬度范围以及良好的阻燃性能。针对PUR-T/PVC合金材料发烟量较大的缺点,引入了表面改性水合氧化铝(ATH)/聚磷酸铵(APP)复配阻燃体系,实验表明,该复配阻燃体系对PUR-T/PVC合金具有一定增韧作用的同时,能够起到较好的抑烟作用,并进一步提升了合金的阻燃性能。经过测试与配方优化,PUR-T添加量为70份、PVC为30份,邻苯二甲酸二辛酯为6份,复配阻燃剂(改性ATH与改性APP质量比为1∶2)添加量为60份时,PUR-T/PVC合金的综合性能最佳,其拉伸强度、断裂伸长率和撕裂强度分别达到23.84MPa,387.18%和86.4N/mm,极限氧指数为32.87%,垂直燃烧等级达到V–0级别,烟密度等级降至52。     

羟基锡酸锌/MPP-PER协同阻燃聚丙烯的性能研究

将三聚氰胺磷酸盐(MPP)、季戊四醇(PER)用于聚丙烯(PP)阻燃改性，研究了羟基锡酸锌(ZHS)对PP抑烟效果的影响。采用极限氧指数(LOI)、UL-94燃烧等级测试、烟密度、锥量测试分析了阻燃PP复合材料的阻燃性能。结果表明，MPP-PER复配能起到较好的阻燃协同作用，能有效提升聚丙烯复合材料的阻燃性能；ZHS的加入能显著降低聚丙烯复合材料的产烟量。当MPP-PER阻燃剂添加量为26%,ZHS的添加量为3%时，LOI达25.1%,UL-94通过V-2级(1.6 mm),燃烧最大比光密度(Ds_max)相比于纯PP降低了23.7%。     

新型磷-氮系复配阻燃剂在聚丙烯中的应用

采用一种新型磷-氮系阻燃剂与聚磷酸铵(APP)复配成膨胀型阻燃剂,对聚丙烯(PP)进行阻燃改性。研究了阻燃PP的阻燃性能、热分解过程及力学性能。结果表明:当复配阻燃剂添加量为30%时,阻燃改性PP的氧指数和垂直燃烧等级分别达到32.3%和UL94 V-0级,拉伸强度为37.4 MPa,缺口冲击强度为39.5 kJ/m2,并且具有很好的热稳定性。     

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。     

阻燃处理对竹粉增强聚乳酸复合材料阻燃抑烟性能影响

分别采用氢氧化铝(ATH)、聚磷酸铵(APP)及ATH+ APP复合阻燃剂对竹粉增强聚乳酸复合材料进行阻燃抑烟处理,并对处理后的复合材料性能进行测试与表征.结果表明,两种阻燃剂均显著增加了复合材料的成炭率,ATH+ APP产生了协同作用,使复合材料成炭率提高了近4倍,达到了45.3％;复合材料经阻燃处理后其阻燃性能均得到了不同程度的提升.其中,APP对复合材料燃烧过程中热量释放的抑制作用最明显,ATH对复合材料表现出了较强的抑烟效果,而ATH +APP复合阻燃剂产生的协同作用使复合材料具有阻燃和抑烟的双重特性.     

Mg(OH)_2-Al(OH)_3-微胶囊红磷协同阻燃POE的研究

以氢氧化镁(MH)、氢氧化铝(ATH)为无卤阻燃剂,微胶囊红磷(MRP)为阻燃增效剂,通过共混挤出制备了一系列的阻燃聚烯烃弹性体(POE)复合材料。采用垂直燃烧、极限氧指数、热失重、傅里叶红外、微型量热分析等方法研究了其阻燃性能及阻燃机理。研究表明,同MH/POE和ATH/POE相比,MH/ATH/POE有较好的阻燃协效性,氧指数达到25.0%,残炭量达到31.7%,但垂直燃烧性能较差(测试无级别)。继续加入6份MRP后,体系的阻燃性能明显提高,其氧指数上升至27.5%,残炭量高达35.2%,垂直燃烧达到V-0级。表明MH/ATH和MRP对POE具有显著的协同阻燃作用。FTIR和TGA实验结果显示,MRP/MH/ATH/POE复合材料燃烧后生成了磷酸及其衍生物,增强了体系的成炭能力,促进了凝聚相阻燃效果,MRP阻燃机理主要表现为凝聚相阻燃。     

Flame retardancy of unsaturated polyester composites with modified ammonium polyphosphate,montmorillonite, and zinc borate

Ammonium polyphosphate (APP) was modified using a new method, where the resulting modified APP (MAPP) was obtained by mixing APP with unsaturated polyester resin (UPR). MAPP was more effective in improving the flame retardancy of UPR than APP which was due to the improved dispersion of MAPP in UPR composite. Then, the UPR composites were prepared based on dimethyl methylphosphonate, MAPP, montmorillonite, and zinc borate. Finally, the flame-retardant and mechanical properties of the UPR composites were analyzed using the limited oxygen index (LOI), thermogravimetric analysis, UL-94 vertical burning test, scanning electron microscopy, cone calorimetry, mechanical tests, and viscosity measurements. The LOI and UL-94 tests showed that the flame-retardant properties clearly improved with the addition of fillers in the UPR composites compared to pristine UPR. The synergistic effect of Si- and P-containing flame retardants in this composite resulted in the LOI value increasing from 18.9 to 31.3% and achieved the UL-94 V-0 rating. Moreover, the heat release rate was lower than the pristine UPR. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47180.     

微胶囊包覆磷钼酸铵的制备、表征及在UPR中的阻燃抑烟性能研究

用原位聚合法制备了蜜胺甲醛树脂微胶囊,并用它对所合成的磷钼酸铵(AMP)进行包覆。粒径分布、SEM结果表明,在n(蜜胺)∶n(甲醛)=1.0∶2.5,pH=2.5,温度为70℃的条件下反应3 h后,再将pH升至6.0,所得微胶囊包覆磷钼酸铵(MCAMP)粒径为7.709μm,胶囊壁呈葡萄串形结构且分散性良好;按w(MCAMP)=5%将MCAMP添加到不饱和聚酯树脂(UPR)中,结果证实,UPR氧指数(LO I)从纯树脂的20.0%上升至25.2%,UL94达V-2级,烟密度等级(SDR)从75.25降至65.11,最大烟密度(MSD)从95.73下降至89.24,烟密度等级满足国家对B1级电器类热固性塑料的使用要求。     

Synergistic flame retardant effects of ammonium polyphosphate in ethylene‐vinyl acetate/layered double hydroxides composites

Mg–Al–Fe ternary layered double hydroxides (LDH) were synthesized based on bayer red mud by calcination‐rehydration method, and characterized using X‐ray diffraction and thermogravimetric analysis (TGA). The synergistic flame retardant effects of ammonium polyphosphate (APP) with LDH in ethylene‐vinyl acetate (EVA) composites were studied using limiting oxygen index (LOI), UL 94 test, cone calorimeter test (CCT), and smoke density test (SDT). The thermal degradation behavior of EVA/LDH/APP composites was examined by thermal gravimetric analysis‐fourier transform infrared spectrometry (TG‐FTIR). The results showed that LOI values decreased by incorporation of APP together with LDH; and, a suitable amount of APP in EVA/LDH composites can apparently improve UL 94 rating. The CCT results indicated that heat release rate (HRR) of the EVA/LDH/APP composites with APP decreased in comparison with that of the EVA/LDH composites. The SDT results showed that APP was helpful to suppress smoke. The TG‐FTIR data showed that the composites with APP had a higher thermal stability than the EVA/LDH composites at high temperature. POLYM. ENG. SCI., 54:766–776, 2014. © 2013 Society of Plastics Engineers     

Synergistic effect of aluminum hydroxide and nanoclay on flame retardancy and mechanical properties of EPDM composites

The composites based on ethylene–propylene–diene monomer rubber (EPDM) with aluminum hydroxide (ATH), nanoclay, vulcanizing agent, and curing accelerator were prepared by conventional mill compounding method. The thermal stability and the flame retardant properties were evaluated by thermogravimetric analysis (TGA), limiting oxygen index (LOI), UL‐94 test, cone calorimeter, and smoke density chamber tests. The results indicated that the substitution of the nanoclay in the EPDM/ATH composites increased the 50% weight loss temperature and the LOI value, and reduced the peak heat release rate (pk‐HRR), the extinction coefficient (Ext Coef), the maximal smoke density (Dm), and the whole smoke at the first 4 min (VOF4) of the test specimens. The synergistic flame retardancy of the nanoclay with ATH in EPDM matrix could imply that the formation of a reinforced char/nanoclay layer during combustion prevents the diffusion of the oxygen and the decomposed organic volatiles in the flame. The mechanical properties of the composites have been increased by replacing more of the nanoclays into the EPDM/ATH blends. The best loading of the nanoclay in EPDM/ATH composites is 3 wt %, which keeps LOI in the enough value, the V‐0 rating in the UL‐94 test, and the improved mechanical properties with better dispersion and exfoliation of the nanoclays shown by transmission electron microscopy (TEM) micrographs. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2042–2048, 2013     

Flame retardation and thermal degradation of intumescent flame‐retarded polypropylene composites containing spirophosphoryldicyandiamide and ammonium polyphosphate

A novel halogen‐free intumescent flame retardant, spirophosphoryldicyandiamide (SPDC), was synthesized and combined with ammonium polyphosphate (APP) to produce a compound intumescent flame retardant (IFR). This material was used in polypropylene (PP) to obtain IFR‐PP systems whose flammability and thermal behavior were studied by the limiting oxygen index (LOI) test, UL‐94, thermogravimetric analysis, and cone calorimetry. In addition, the mechanical properties of the systems were investigated. The results indicated that the compound intumescent flame retardant showed both excellent flame retardancy and antidripping ability for PP when the two main components of the IFR coexisted in appropriate proportions. The optimum flame retardant formulation was SPDC:APP = 3:1, which gave an LOI value of 38.5 and a UL‐94 V‐0 rating. Moreover, the heat release rate, production of CO, smoke production rate, and mass loss rate of the IFR‐PP with the optimum formulation decreased significantly relative to those of pure PP, according to the cone calorimeter analysis. The char residues from the cone calorimetry experiments were observed by scanning electron microscopy, which showed that a homogeneous and compact intumescent char layer was formed. J. VINYL ADDIT. TECHNOL., 2010. © 2010 Society of Plastics Engineers     

Flame retardant and mechanical properties of epoxy composites containing APP−PSt core−shell microspheres

Ammonium polyphosphate (APP)–polystyrene (PSt) core–shell microspheres (CSPs) were synthesized via in situ radical polymerization. The core–shell structure was confirmed by transmission electron microscope (TEM). The results of optical contact angle measurements demonstrated a significant improvement in hydrophobicity of the modified APP. The obtained APP–PSt CSPs were added into epoxy (EP) system with various loadings. Effects of CSP on flame retardancy, thermal properties, heat release rate (HRR), smoke production, and mechanical properties of EP/CSP composites were investigated by limiting oxygen index (LOI), UL‐94 tests, thermogravimetric analysis (TGA), cone calorimeter, and tensile test. LOI and UL‐94 indicated that CSP remarkably improved the flame retardancy of EP composites. TGA showed that the initial decomposition temperature and the maximum‐rate decomposition temperature decreased, whereas residue yields at high temperature increased with the incorporation of microspheres. Cone calorimetry gave evidence that HRR, peak release rate, average HRR, and smoke production rate of EP/CSP composites decreased significantly. The morphology of char residues suggested that CSP could effectively promote EP to form high‐quality char layer with compact outer surface and swollen inner structure. Tensile strength of EP was enhanced with the addition of CSP. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40218.     

新型磷系阻燃剂四苯基(双酚-A)二磷酸酯阻燃PC/ABS的研究

利用自制的四苯基(双酚-A)二磷酸酯(BDP)及其复配体系制备了阻燃PC/ABS,研究了阻燃PC/ABS的力学性能、氧指数(LOI)和垂直燃烧测试性能(UL94)、材料的阻燃性能和烟气释放。结果表明:采用15%的BDP阻燃PC/ABS,材料的冲击强度下降了12.82%,LOI达到30.0%,UL94阻燃性能达到V—0级,平均热释放速率(av-HRR)和最大热释放速率(pk-HRR)分别下降了35.84%和31.17%,点燃时间(TTI)延长18s,火势增长指数(FGI)下降了46.72%,比消光面积(SEA)上升了6.68%;采用BDP/APP复配阻燃PC/ABS,材料的冲击强度最大降幅为33.33%,LOI最大可达30.1%,UL94阻燃性能由V—0级降为V—1级,av-HRR和pk-HRR最大分别下降40.89%和31.2%,TTI最大延长20s,FGI最大降幅为50.37%,SEA最大涨幅为11.14%;采用BDP/纳米SiO2复配阻燃PC/ABS,当纳米SiO2的添加量为7%时,材料的冲击强度上升了5.13%,LOI达到31.1%,UL94阻燃性能达到V—0级,av-HRR和pk-HRR分别下降了43.18%和4069%,TTI延长20s,FGI降幅为59.12%,平均比消光面积(av-SEA)涨幅为8.09%,6min内av-SEA下降6.92%,(6min总发烟指数)TSPI6min下降5.54%,阻燃、抑烟效果最佳,对PC/ABS材料的力学性能影响最小。     

木粉及聚磷酸铵对PE-HD木塑复合材料阻燃和力学性能的影响

以高密度聚乙烯(PE-HD)为基体,聚磷酸铵(APP)和木粉(WF)为膨胀型阻燃体系,制备了阻燃木塑复合材料(WPC)。通过极限氧指数、垂直燃烧UL 94、锥形量热分析、热失重分析、红外光谱分析、力学性能等对其进行性能表征。结果表明,与纯PE-HD相比,极限氧指数随着WF含量增加而提高,添加40 %WF时极限氧指数提高到30.5 %,UL 94可达V-0等级,热释放速率峰值和总热释放量降低;APP和WF燃烧过程中发生了化学作用,形成了保护炭层,提高了材料的热稳性,材料的拉伸和弯曲强度得到提高。     

Synthesis of novel triazine charring agent and its effect in intumescent flame‐retardant polypropylene

A novel charring agent (CNCA‐DA) containing triazine and benzene ring, using cyanuric chloride, aniline, and ethylenediamine as raw materials, was synthesized and characterized. The effects of CNCA‐DA on flame retardancy, thermal degradation, and flammability properties of polypropylene (PP) were investigated by limited oxygen index (LOI), vertical burning test (UL‐94), thermogravimetric analysis (TGA), and cone calorimeter test (CCT). The TGA results showed that CNCA‐DA had a good char forming ability, and a high initial temperature of thermal degradation; the char residue of CNCA‐DA reached 18.5% at 800°C; Ammonium polyphosphate (APP) could improve the char residue of APP/CNCA‐DA system, the char residue reached 31.6% at 800°C. The results from LOI and UL‐94 showed that the intumescent flame retardant (IFR) containing CNCA‐DA and APP was very effective in flame retardancy of PP. When the mass ratio of APP and CNCA‐DA was 2 : 1, and the IFR loading was 30%, the IFR showed the best effect; the LOI value reached 35.6%. It was also found that when the IFR loading was only 20%, the flame retardancy of PP/IFR can still pass V‐0 rating in UL‐94 tests, and its LOI value reached 27.1%. The CCT results demonstrated that IFR could clearly change the decomposition behavior of PP and form a char layer on the surface of the composites, consequently resulting in efficient reduction of the flammability parameters, such as heat release rate (HRR), total heat release (THR), smoke production rate (SPR), total smoke production (TSP), and mass loss (ML). © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012