阻燃LGFPP的阻燃性能研究

将有机蒙脱土(OMMT)和水滑石(LDH)分别与膨胀阻燃剂(IFR)构成阻燃体系,对长玻纤增强聚丙烯(LGFPP)复合材料进行阻燃改性,通过极限氧指数(LOI)和锥形量热仪(CONE)测试,对比研究了两种体系阻燃LGFPP的阻燃性能及阻燃机理。结果表明:当OMMT质量分数为2%时,复合材料的LOI达到最大值24.2%,且垂直燃烧达到了UL-94 V-0级;当LDH质量分数为1%时,LOI达到最大值23.3%,而垂直燃烧等级仍为V-1级。以炭层阻隔的IFR/OMMT体系比以稀释阻燃的IFR/LDH体系更加有效地改善LGFPP的阻燃性能。     

有机-金属杂化化合物阻燃聚丙烯的研究

将有机-金属杂化三嗪化合物（SCTCFA-ZnO）与聚磷酸铵（APP）复配制备了膨胀型阻燃剂（IFR）,通过极限氧指数测试、垂直燃烧测试、锥形量热分析、热失重分析和扫描电子显微镜分析等表征方法研究了SCTCFA-ZnO/APP的协同作用对PP复合材料阻燃性能的影响。结果表明,APP与SCTCFA-ZnO复配可以有提高PP材料的阻燃性能,当IFR的添加量为25 %（质量分数,下同）,且APP/SCTCFA-ZnO的质量比为2/1时,复合材料的极限氧指数最高,达到31.1 %,达到UL 94 V-0级;IFR可提高复合体系的温热稳定性,阻燃复合材料燃烧后会形成一层致密、连续的炭层,从而起到良好的阻燃效果。     

无卤阻燃改性增强尼龙6性能的研究

采用自制的无卤阻燃剂（IFR）对30％玻纤增强尼龙6复合材料进行阻燃改性,研究了IFR的不同加入量对复合材料阻燃性能、力学性能以及热性能的影响。结果表明：当IFR加入量为25％时．阻燃复合材料的极限氧指数（LOI）达到31,阻燃级别为V-0级,而拉伸强度为78．86MPa,冲击强度为5．06kJ／m^2,材料综合性能比较优异。热重分析（TGA）数据表明,IFR的加入,改变了复合材料的热分解行为,改善了成炭效果。     

无卤膨胀阻燃长玻纤增强聚丙烯性能研究*

利用无卤膨胀阻燃剂(IFR)阻燃长玻纤增强聚丙烯(LGFPP)复合材料,研究IFR的添加量对复合材料阻燃性能、热稳定性能、燃烧性能和力学性能的影响。结果表明,加入IFR使复合材料燃烧后生成了具有阻燃作用的炭层,显著提高了复合材料的阻燃性能。随IFR添加量的增加,复合材料的极限氧指数(LOI)逐渐提高,热释放速率峰值及其平均值、总热释放速率和生烟速率逐渐降低,力学性能略有下降。当IFR质量分数为20%时,复合材料的LOI和垂直燃烧等级分别达到了24.4%和UL 94 V-0级。     

新型成炭剂对PE-LD阻燃性能的影响

以多聚磷酸铵（APP）与新型成炭剂（CNCH-DA）复配成新型膨胀型阻燃剂（IFR）,采用氧指数测定仪、垂直燃烧测定仪、微型量热仪、热重分析仪和扫描电子显微镜研究了CNCH-DA 对低密度聚乙烯（PE-LD）/IFR复合材料阻燃性能的影响。结果表明,当APP与CNCH-DA以质量比5:1复配时,PE-LD/IFR复合材料的极限氧指数达到27.5 %,且达到UL 94 V-0级;当APP与CNCH-DA复配后,PE-LD的燃烧性能下降;APP与CNCH-DA复配后,PE-LD/IFR复合材料的热降解有所推迟;PE-LD/IFR在燃烧后能形成致密且蓬松的炭层,起到良好的阻燃效果,而PE-LD/CNCH-DA则形成蓬松而不致密的微球,阻隔能力差。     

硅胶与膨胀型阻燃剂复配阻燃LGF/PP复合材料的性能研究

研究硅胶(SG)作为协效剂与IFR协同阻燃LGF/PP复合材料的性能。通过极限氧指数(LOI)、垂直燃烧(UL-94)、锥形量热仪(CONE)、热重分析法(TG)、扫描电子显微镜(SEM)、力学性能等测试表征LGF/PP/IFR/SG阻燃复合体系的性能。结果表明:当硅胶用量为2%时,阻燃复合材料的LOI为29.4%,且燃烧等级达到V-0级;CONE测试结果表明LGF/PP/IFR/SG阻燃复合材料的第一热释放速率峰值降低,而第二热释放速率峰消失;LGF/PP/IFR/SG阻燃复合材料具有较好的热稳定性,且产生致密均匀的炭层;并研究硅胶用量对复合材料力学性能的影响。     

LGFPP/IFR/SP阻燃复合材料的协同阻燃机理

以海泡石(SP)作为协效剂,研究SP与膨胀型阻燃剂(IFR)协同阻燃LGFPP复合材料的性能。通过极限氧指数(LOI)、垂直燃烧(UL-94)、热重分析(TG)等表征LGFPP/IFR/SP复合材料的协同阻燃性能及协效机理。结果表明:随着SP协效剂用量增加,LGFPP/IFR/SP复合材料的LOI呈先增加后降低的趋势,当SP用量为1%时,复合材料的LOI为29.3%,燃烧等级达到V-0级;Ozawa法计算得到复合材料的活化能随着失重率的增大而增大;在LGFPP/IFR/SP阻燃协效体系中,海泡石主要为化学协效阻燃机理。     

无机填料填充PE-LD/EVA合金的导热及阻燃性能

采用氧化铝（Al2O3）为导热填料、氢氧化镁［Mg(OH)2］为阻燃填料,以低密度聚乙烯（PE-LD）和乙烯醋酸乙烯共聚物（EVA）为基体树脂制备导热阻燃复合材料。通过导热性能测试、燃烧行为表征（极限氧指数和垂直燃烧测试）以及热重分析研究了PE LD/EVA/Al2O3/Mg(OH)2复合材料的导热性能、阻燃性能及热稳定性。结果表明,含有50份Al2O3及50份Mg(OH)2的复合材料,在PE-LD/EVA质量比为1/1时,热导率可达到1.21 W/m·K;材料的阻燃性能及热稳定性都随 EVA 含量的增加而增大,极限氧指数从27.0 % 提高到31.5 %,UL 94 垂直燃烧从无等级提高到V-0级,残炭率从46.5 %提高到57.7 %。     

膨胀型阻燃剂/二乙基次磷酸铝阻燃改性不饱和树脂基复合材料

采用密胺包覆聚磷酸铵（APP）、季戊四醇（PER）和三聚氰胺（MEL）作为膨胀型阻燃剂（IFR）对不饱和树脂（UP）进行改性,研究了APP、PER和MEL不同复配比例及用量对不饱和树脂基复合材料阻燃性能和力学性能的影响。基于IFR最佳用量,以二乙基次磷酸铝（ADP）为协效剂,研究了ADP用量对IFR/UP阻燃复合材料阻燃性能、力学性能及热稳定性的影响。结果表明,当APP∶PER∶MEL复配比例为4∶1∶1,IFR添加量为15 %（质量分数,下同）时,复合材料综合性能最佳,其极限氧指数为27.4 %,UL 94垂直燃烧达到V?1等级,弯曲强度和冲击韧性分别为100.3 MPa和6.3 kJ/m²;ADP的引入能够进一步提高IFR/UP复合材料阻燃性能,且随着ADP质量分数的增加而增强;当ADP质量分数为2 %时,IFR?ADP/UP复合材料极限氧指数为28.5 %并达到V?0阻燃等级,弯曲强度和冲击韧性分别为110 MPa和7.8 kJ/m²,与IFR/UP复合材料相比,分别提高了9.7 %和23.8 %;ADP能够促进IFR/UP复合材料表面成炭,缓解基体的热降解。     

4A分子筛和SiO2对EVA/IFR复合材料性能的影响

以聚磷酸铵(APP)复配季戊四醇(PER)为膨胀型阻燃剂(IFR)制备了无卤阻燃乙烯-醋酸乙烯共聚物(EVA)/IFR复合材料,通过极限氧指数仪、热失重分析仪及扫描电子显微镜研究分析了4A分子筛和SiO2的加入对复合材料阻燃性能、热稳定性能及复合材料残炭表面形貌的影响。结果表明,加入4A分子筛可以明显提高复合材料的极限氧指数,当添加1份4A分子筛时,复合材料的极限氧指数达到31%,比未添加时提高了2%;4A分子筛的加入使复合材料在燃烧过程出现熔融滴落现象;继续加入SiO2可以进一步提高复合材料的极限氧指数,当添加3份SiO2时,复合材料的垂直燃烧测试达到V-0级。     

天然高分子对生物聚酯P(3,4)HB复合材料阻燃性能的影响

以三聚氰胺磷酸盐(MP)和季戊四醇磷酸酯(PEPA)复配的膨胀型阻燃体系阻燃聚(3-羟基丁酸酯-co-4-羟基丁酸酯)[P(3,4)HB], 分别用木质素、壳聚糖和海藻酸钠3种天然高分子作为成炭剂代替部分PEPA, 采用熔融共混法制备P(3,4)HB基阻燃复合材料。通过热重分析仪(TGA)、微型量热仪(MCC)、垂直燃烧仪(UL-94)、极限氧指数仪(LOI)及扫描电镜(SEM)等对其热稳定性、热燃烧性能、阻燃特性及炭渣形貌进行了表征与分析, 对比研究了3种天然高分子对P(3,4)HB基复合材料阻燃性能的影响。结果表明:含有木质素的复合材料体系燃烧后形成了致密而连续的炭层, 且能达到V-0级别, 而含壳聚糖或海藻酸钠的复合材料体系燃烧后形成的炭层结构多孔而疏松, 只能达到V-2级。     

EG与IFR复合阻燃ABS的动态燃烧性和协同效应

将可膨胀石墨(EG)与P-N型膨胀阻燃剂(IFR)复合阻燃丙烯腈-丁二烯-苯乙烯共聚物(ABS)树脂,阻燃剂添加量为20%(质量分数,下同),通过极限氧指数(LOI)仪、垂直燃烧测试(UL-94)仪、锥形量热(CONE)仪和扫描电镜(SEM)研究了EG与IFR复合阻燃ABS的协同效应。结果表明,EG/IFR质量比为1/1为最佳配比,阻燃ABS的LOI达到29%,UL-94为V-0级;EG与IFR复合阻燃ABS,表现出一定的协同作用;通过SEM观察ABS/EG/IFR试样燃烧后样品发现,EG与IFR起到协同阻燃作用。     

硅酮粉协同膨胀阻燃剂阻燃HIPS研究

通过熔融共混制备硅酮粉(GM)协同膨胀阻燃剂(IFR)阻燃的高抗冲聚苯乙烯(HIPS)复合材料,并通过红外光谱、扫描电子显微镜、热重分析、X射线衍射以及电子拉力机等对材料和残炭进行表征。结果表明:与只加入IFR相比,GM的加入能明显提升阻燃材料的力学性能,改善IFR与HIPS的相容性,有效提高HIPS的阻燃性能。当加入2%GM和33%IFR时,阻燃HIPS的极限氧指数达到31%、UL-94测试达到V-0级。     

Synergistic effect of MXene on the flame retardancy and thermal degradation of intumescent flame retardant biodegradable poly (lactic acid) composites

The effect of Ti₃C₂ MXene nanosheets on the intumescent flame retardant (IFR) poly (lactic acid) (PLA) composites was investigated among a series of PLA/IFR/MXene, which were prepared by melt blending 0-2.0 wt% MXene, 10.0 wt%-12.0 wt% IFR and PLA together. The results of limiting oxygen index (LOI) and vertical burning (UL-94) discover that the combination of 0.5 wt% MXene and 11.5 wt% IFR synergistically improves the fire safety of PLA to reach UL-94 V-0 rating with LOI value of 33.0%. The PLA/IFR/MXene composites perform an obvious reduction in peak of heat release rate (HRR) in cone calorimeter tests (CCTs). Furthermore, the carbon residues after CCTs were characterized by scanning electron microscope (SEM), laser Raman spectroscopy (LRS), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). It is demonstrated that both the titanium composition of the MXene structure and the characteristics of the two-dimensional material enhance the PLA/IFR/ MXene composite materials' ability to produce a dense barrier layer to resist burnout during thermal degradation.     

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.     

Vinyl polysiloxane microencapsulated ammonium polyphosphate and its application in flame retardant polypropylene

Vinyl polysiloxane microencapsulated ammonium polyphosphate (MAPP) was prepared by a sol-gel method using vinyltrimethoxysilane as a precursor to improve its thermal stability and hydrophobicity. The MAPP was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS) and thermogravimetric analyzer (TGA). The results showed that ammonium polyphosphate (APP) was successfully coated with vinyl polysiloxane. MAPP and pentaerythritol (PER) were used together to improve the flame retardancy of polypropylene (PP). The flame retardant properties of PP composites were investigated by limiting oxygen index (LOI), UL-94 test, TGA and SEM. When the MAPP was added as a flame retardant, with PER as a char forming agent, the LOI of PP/MAPP/PER composites was 33.1%, and it reached the UL-94 V-0 level. The results also demonstrated that the flame retardant properties of PP/MAPP/PER composites were better than those of PP/APP/PER composites at the same loading. Moreover, the addition of flame retardant and carbon forming agent could promote the crystallization behavior of PP.     

有机化坡缕石黏土-膨胀型阻燃聚丙烯复合材料的制备及性能

制备了优异阻燃性能(LOI36%)兼具良好力学性能的膨胀型阻燃聚丙烯复合材料OPGS/PA-APP/PP。将有机化坡缕石黏土引入到哌嗪-多聚磷酸铵(PA-APP)膨胀型阻燃(IFR)聚丙烯(PP)复合材料中,通过极限氧指数(LOI)、垂直燃烧(UL-94)、热重分析法(TGA)、扫描电子显微镜(SEM)、通用电子万能试验机研究了有机化坡缕石黏土添加量对PA-APP阻燃聚丙烯复合材料阻燃性能和力学性能的影响。结果表明,添加质量分数为2%的有机化坡缕石黏土提高了该复合材料的阻燃性能和力学性能。此外,所制备样品经垂直燃烧测试可达到阻燃V-0级别。实验证明,有机化坡缕石黏土在膨胀型阻燃聚丙烯复合材料中具有明显的协效阻燃作用。     

Nickel-Aluminum Hydrotalcite for Improving Flame Retardancy and Smoke Suppression of Intumescent Flame Retardant Polypropylene: Preparation,Synergy, and Mechanism Study

Intumescent flame retardants (IFR) are widely used in the field of flame retardant polypropylene (PP), but their flame retardant efficiency and smoke suppression properties need to be further improved. Herein, a Ni-Al LDH (layered double hydroxide) is obtained successfully by coprecipitation and microwave hydrothermal technique and used as a synergist to improve the flame-retardant and smoke-suppression properties of triazine-based IFR. The results showed that IFR/Ni-Al LDH exhibited the best synergistic effect when the IFR is replaced by 5 wt% Ni-Al LDH. 17 wt% IFR/Ni-Al LDH enabled the PP composites to achieve UL-94 V-0 rating with a high LOI of 29.8%. Besides, the introduction of Ni-Al LDH effectively decreased the heat and smoke release of the PP/IFR composites due to its catalytic charring effect. This is mainly attributed that the introduction of metal ions in Ni-Al LDH effectively improved the strength and crosslinking degree of char layer and promoted the formation of a cohesive and dense char layer. The formed high-quality char layer effectively exerted the barrier effect in condensed phase. Therefore, the PP/IFR/Ni-Al LDH composites exhibited excellent flame-retardant and smoke-suppression performance. This investigation provided a facile way to prepare environment-friendly and high-performance flame retardant PP composites with wide application prospects.     

Synergistic effects of molybdenum disulfide on a novel intumescent flame retardant polyformaldehyde system

A novel intumescent flame retardant (IFR) composed of ammonium polyphosphate (APP), benzoxazine containing trialkoxysilane (BA-a-Si) and melamine (ME), is compounded with different specifications of MoS₂ as synergist to flame retard polyformaldehyde (POM). The flame retardancy and mechanism of the composites are analyzed by limiting oxygen index (LOI), vertical combustion (UL-94) and cone calorimeter. At the same time, the mechanical properties and lubricating properties are tested by electromechanical testing machine and wear testing machine. The experimental results show that MoS₂ has a good synergistic effect with IFR, and the smaller the average particle size of MoS₂ is, it seems to be more beneficial to improve the flame retardancy of POM composites. Only a small amount of MoS₂ (0.8 wt%) is needed to synergize with IFR, the flame retardant POM composite (FR-POM) can achieve UL-94 (3.2 mm) V-0 rating, LOI of 62.5%, and heat release rate reduction of 25.3%, total smoke release decreased by 29.5%. In addition, from the mechanical properties analysis, it is found that the microscale MoS₂(M2) can better improve the bending and tensile properties of the FR-POM composites, while the nanoscale MoS₂(N80) is more helpful to improve the lubricating properties.