红磷改性MCA阻燃PA6性能研究

采用红磷对三聚氰胺氰尿酸盐(MCA)进行改性,作为尼龙(PA)6的阻燃剂,研究不同红磷含量改性MCA的结构及阻燃PA6体系的阻燃性能。结果表明,红磷通过干扰三聚氰胺和氰尿酸大平面氢键网络的形成,实现MCA细化。红磷能促进MCA成炭,改性MCA从气相和凝聚相协同阻燃,提高了PA6的阻燃性能。当改性MCA中红磷含量为20%、改性MCA用量为10%时,PA6的阻燃效果最好。     

原位聚合无卤阻燃聚酰胺6的结构与性能研究

采用原位聚合添加反应型无卤阻燃剂,是实现聚己内酰胺(PA6)阻燃改性的主要方法。在己内酰胺的水解开环聚合体系中,加入三聚氰胺氰尿酸盐(MCA)的原料单体,原位聚合制备了阻燃PA6(FRPA6),对FRPA6的结构、形貌及性能进行了表征;通过熔融纺丝制备了FRPA6纤维,测试了其力学性能及阻燃性能。结果表明:FRPA6中阻燃剂MCA与PA6基体的相容性良好,MCA自组装反应比较充分,MCA粒子以纳米级均匀分布于PA6基体中;随着MCA含量的增加,FRPA6的熔点、熔融热焓有所降低,结晶温度略有升高,热稳定性下降;当MCA质量分数为7.5%时,FRPA6的阻燃性能达UL94 V-0级,拉伸强度为64.1 MPa,缺口冲击强度为10.4 k J/m2;相比纯PA6纤维,FRPA6纤维具有较好的阻燃性能,极限氧指数达35%以上,但力学性能有所下降。     

氮–磷协效阻燃聚酰胺66制备与性能

为改善聚酰胺66(PA66)的阻燃性能,以氮系阻燃剂三聚氰胺氰尿酸盐(MCA)和磷系阻燃剂9,10–二氢–9–氧杂–10–磷酰杂菲–丁二酸(DDP)协效,将原位聚合法与共聚法结合,经熔融缩聚制备氮-磷协效阻燃PA66树脂。利用傅立叶变换红外光谱仪、差示扫描量热仪、万能材料试验机、垂直燃烧仪和极限氧指数仪等研究阻燃PA66树脂的结构与性能。结果表明:随DDP含量的增加,阻燃PA66的相对黏度、熔点、结晶度和力学性能均呈下降趋势。当MCA含量为2%,DDP含量为4%时,阻燃PA66(FRPA66–4)的熔点、结晶温度和结晶度分别降至250.78℃,203.74℃,29.21%,FRPA66–4的拉伸强度和断裂伸长率分别下降为68.8 MPa和69.5%,比PA66降低了17.01%和17.46%。但PA66的阻燃性能得到改善,FRPA66–4的垂直燃烧测试达UL94 V–0级,极限氧指数为30.6%,阻燃效果良好。     

改性MCA的固相合成及其在PA6中的应用

本实验选用一种新的方法合成改性三聚氰胺氰尿酸盐(MCA),将三聚氰胺(MA)、氰尿酸(CA)和极少量水混合成膏状物并使其在室温下反应一定时间,再加入少量MCA和二氧化硅(Si O2)溶胶使其继续反应以制备改性MCA(mMCA)阻燃剂。将制备的mMCA与尼龙6(PA6)熔融共混制备阻燃PA6复合材料。用FTIR、XRD和TG对所制mMCA进行了表征,对阻燃PA6复合材料的阻燃性能和力学性能进行了测试。结果表明:所制mMCA的FTIR、XRD特征峰与MCA的特征峰一致;m MCA的最大热失重温度有了较大的提升达到465.2℃。在PA6复合材料中,当阻燃剂含量为13%时,阻燃PA6复合材料的极限氧指数(LOI)达到33%,阻燃性能为UL-94 V0级,锥形量热测试的PHRR降低了26.3%。随着阻燃剂含量的增加,复合材料的力学性能有所提高。与传统大量水体系制备mMCA方法相比,此法具有工艺简单、不需加热、耗水量极低,没有污水排放等优点。     

SA／CaSt改陛氯氧化镁／MCA阻燃抗熔滴PA6的性能研究

以硫酸镁与氨水为原料,采用硬脂酸／硬脂酸钙作为复合改性剂,合成改性氢氧化镁阻燃剂。将制备的改性氢氧化镁与三聚氰胺氰尿酸盐（MCA）添加到尼龙（PA6）中,通过挤出造粒制备复合阻燃（PA6）。分别研究不同阻燃剂配比对复合材料力学性能、耐热性能、阻燃性能及机理的影响。结果表明：随着MCA／改性氢氧化镁比例的增大,复合阻燃PA6的拉伸性能与冲击性能均先上升后下降,当两者比例为1：1时,力学性能达到最优。同时,两阻燃剂协同作用,使尼龙6阻燃机理由解聚分解转化为直接炭化分解,有效抑制燃烧流滴现象,提高了复合材料的综合阻燃性能。     

芳香席夫碱基阻燃剂的制备及其在聚酰胺6中的应用

为提高聚酰胺6(PA6)用反应型阻燃剂的热稳定性，以对苯二甲醛（TPAL）、对氨基苯甲酸（PABA）、9,10-二氢-9-氧代-10-磷杂菲-10-氧化物（DOPO）与二苯基氧膦（DPO）为原料，制备芳香席夫碱基磷氮协效阻燃剂TMADOPO和TMA-DPO，对产物的结构及热稳定性进行表征。通过熔融共聚制备阻燃PA6(FRPA6s)，在TMA-DOPO中分别引入二乙基次磷酸铝（AlPi）和三聚氰胺氰尿酸盐（MCA）以协效阻燃，研究阻燃剂对PA6相对黏度、热稳定性、阻燃性能和力学性能的影响。结果表明：TMA-DOPO的热稳定性更优异。引入阻燃剂后，FRPA6s的热稳定性、相对黏度、拉伸强度均下降，阻燃性能提高。相比PA6，当TMA-DOPO与MCA（或AlPi）引入量分别为己内酰胺质量的5%、3%,TMA-DPO引入量为7%时，使FRPA6s垂直燃烧达到V-0级，极限氧指数（LOI）分别提升至30.7%、30.3%和29.7%。     

原位聚合型阻燃尼龙6纤维的制备及性能研究

利用原位聚合的方式,在己内酰胺水解聚合体系中引入三聚氰胺氰尿酸盐(MCA)阻燃剂,一次性制备出MCA/尼龙6(PA6)阻燃复合材料。利用这种复合材料进行熔融纺丝,通过扫描电镜(SEM)考察了阻燃纤维的相容性。MCA粒子在PA6基体树脂中均匀分布,没有发生团聚现象。通过测定阻燃纤维的力学性能,发现MCA加入量在7.2%和10.0%的阻燃纤维的断裂强度与断裂强力都有一定程度的降低,但断裂伸长率变大。阻燃剂含量在7.2%和10.0%的MCA/PA6阻燃纤维极限氧指数(LOI)能达到35%以上,具有较佳的阻燃性能。     

花球状锆酸酯改性氢氧化镁/MCA协同阻燃PA6性能

将硬脂酸和硬脂酸钙作为复合改性剂,制得改性氢氧化镁(MH),并用偶联剂(Zr-801)对所得到的粉体进行表面包覆,通过重组自组装合成花球状锆酸酯改性MH。以聚酰胺(PA6)为基体,三聚氰胺氰尿酸盐(MCA)为主阻燃剂,锆酸酯改性MH为协效阻燃剂,制备了PA6复合材料。研究和对比了锆酸酯改性MH的添加量对复合材料阻燃性能和力学性能的影响,并分析了其阻燃机理。结果表明,锆酸酯改性MH的加入能有效提高体系的力学性能,且添加质量分数6%时达到最优;复合材料的氧指数增大,熔滴现象减弱,成炭效果好,综合阻燃性能提高。     

三聚氰胺氰尿酸盐/聚氨酯复合阻燃剂阻燃PA66的研究

采用三聚氰胺氰尿酸盐(MCA)/聚氨酯(TPU)复合阻燃剂阻燃PA66,解决了单独使用MCA阻燃PA66熔滴引燃脱脂棉问题,可使1．6 mm样条通过UL94V-0级别；研究了MCA/TPU复合阻燃剂阻燃PA66的阻燃机理,考察了阻燃材料的力学性能。     

无卤阻燃尼龙66的研究

采用分子复合改性三聚氰胺氰尿酸盐(M-MCA)为阻燃剂制备了无卤阻燃(非增强)尼龙66(PA66).研究表明:与传统三聚氰胺氰尿酸盐(MCA)相比,M-MCA阻燃PA66具有自熄时间短、熔滴无火焰的特点,在8％添加量时即可通过UL94V-0( 1.6 mm)阻燃级别,阻燃材料力学性能优良,综合性能良好.采用热重分析仪(TGA)、微型量热仪(MCC)对材料燃烧成炭行为进行分析,研究其阻燃机理.     

类石墨氮化碳及其MCA杂化物的合成与阻燃

采用三聚氰胺作为原料,通过梯度加热制备了类石墨氮化碳(g-C3N4),再以三聚氰胺、氰尿酸和自制g-C3N4合成了三聚氰胺氰尿酸杂化物(CNMCA)。采用FTIR、XRP和TDA对g-C3N4和CNMCA的结构与热性能进行了表征。将CNMCA应用在聚酰胺6中制备了阻燃复合材料,同时,采用垂直燃烧和极限氧指数法分析了阻燃效果。结果表明,g-C3N4具有较高的热稳定性,其热失重5%(T-5%)的温度高达544.9℃。另外,g-C3N4的杂化不同程度地提高了MCA的热稳定性。当杂化比例为30%时,CNMCA的T-5%由345.5℃提升到352.3℃,在600℃下的残余质量由0.43%显著提升到23.45%。CNMCA的阻燃性能比MCA更佳,当添加到10%CNMCA30时,试样燃烧时的熔滴已无法使脱脂棉被引燃,因此,阻燃等级从UL94 V-2提升到UL94 V-0级,极限氧指数也从27.8%提升至31.3%。     

The effect of morphology on the flame‐retardant behaviors of melamine cyanurate in PA6 composites

Three types of melamine cyanurate (MCA) with micrometer‐size sphere‐like, micrometer‐scale rod‐like, and nanometer‐scale flake‐like morphologies were synthesized by changing the chemical circumstances of the reactions. The microcosmic morphologies of MCA were characterized via scanning electron microscopy and X‐ray diffraction. After the MCAs with different morphologies were incorporated into polyamide 6 (PA6), the flame‐retardant properties of the MCA/PA6 composites were investigated using the limited oxygen index (LOI), UL94, and cone calorimeter tests. The MCA/PA6 composites with nanometer‐scale flake‐like MCA obtained an LOI value of 29.5% and a UL94 V‐0 rating, which were higher than those with micrometer‐size sphere‐like and rod‐like MCAs. However, the different morphologies did not affect the heat release rate, total smoke release, average carbon monoxide yield, and average carbon dioxide yield based on the cone calorimeter. The flame‐retardant mechanism of MCAs with different morphologies was investigated via thermal gravimetric analysis (TGA) and TGA‐Fourier transform infrared spectra. The results show that the different morphologies of MCA resulted in different dispersed evenness of MCA. Further, the nanometer‐scale flake‐like morphology of MCA brought more interactions of hydrogen bond between MCA and PA6, which resulted in the delay of MCA decomposition and the enhancement of MCA flame‐retardant effect. The nanometer‐scale flake‐like MCA had a better performance compared with the other samples because of the delaying and even release of flame‐retardant effect by the decomposition of evenly dispersed MCA. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40558.     

Melamine cyanurate surface treated by nylon of low molecular weight to prepare flame‐retardant polyamide 66 with high flowability

In the present research, a nitrogen‐based flame‐retardant, melamine cyanurate (MCA) was surface‐treated with low‐molecular‐weight nylon through a solvent process to further improve its flowability and dispersion. The surface energy and flow energy of the modified MCA were investigated. The properties of polyamide 66 (PA66) prepared with surface‐treated and with conventional MCA were evaluated and compared. Because of lower surface energy and flow energy for modified MCA, its agglomeration degree and flow resistance are obviously decreased compared with conventional MCA, thus achieving finer and more homogenous dispersion in the PA66 matrix. Moreover, the low‐molecular‐weight nylon resin encapsulating MCA surface will melt at lower temperature during compounding with PA66; hence, it serves as a lubricant and carrier to further improve the flowability and dispersion of the flame retardants. Based on these advantages, the modified MCA flame‐retardant PA66 achieves much better flame retardancy, flowability, and mechanical properties compared with conventional MCA/PA66 under the same loading level of flame retardant (10 wt%).     

电子电器用MCA阻燃PA66的研制

应用不同厂家的三聚氰胺脲酸盐(MCA)阻燃尼龙(PA)66,筛选出满足PA66加工条件的MCA,考察了其用量及表面处理对PA66阻燃性能和力学性能的影响,并对MCA阻燃PA66进行增韧改性研究.结果表明,E厂家提供的MCA满足PA66的加工条件,且其堆密度和白度较为优良.采用E厂家的MCA,当其用量为12～14份时阻燃...     

三聚氰胺氰尿酸盐/氧化锑/石墨烯复合阻燃玻璃纤维增强聚酰胺6复合材料

研究了阻燃剂三聚氰胺氰尿酸盐（MCA）/氧化锑（Sb2O3）和石墨烯（GP）对玻璃纤维（GF）增强聚酰胺6（PA6）复合材料性能的影响。结果表明,MCA/Sb2O3（质量比为70/30）的加入改善了PA6和GF的相容性,与不添加阻燃剂的PA6/GF相比,当MCA/Sb2O3含量为30份时,复合材料的强度、刚性和阻燃性能显著提高;GP的加入对PA6/GF的力学性能影响不大,但阻燃性能明显提高,当GP的含量为0.3份时,复合材料的极限氧指数达到30.1 %,阻燃等级达到UL 94 V-0级;GP在PA6/GF的燃烧过程中具有促进炭化和发泡双重作用。     

Effect of halloysite nanotubes on thermal and flame retardant properties of polyamide 6/melamine cyanurate composites

In this study, polyamide 6 (PA6) with various contents of halloysite nanotubes (HNTs) and melamine cyanurate (MCA) were prepared by a twin‐screw extruder. The flame retardant and physical properties of PA6 composites were examined. X‐ray diffraction (XRD) patterns of PA6/HNTs and PA6/MCA/HNTs composites showed that HNTs as a nanoscale material dispersed in PA6 whether with MCA or not. Thermo gravimetric analyzer (TGA) results showed the presence of HNTs can improve thermal stability of PA6 and PA6/MCA composites. The incorporation of HNTs seemed to result the increase of crystallinity of PA6 and PA6/MCA composites from the differential scanning calorimetry (DSC) results. The combined of HNTs and MCA that leads to further improvements limiting oxygen index (LOI) value of PA6 to 31.7% exerted a positive effect on flame retardancy of PA6. What's more, some mechanical enhancements of PA6 with adding of HNTs were achieved and HNTs also made the tensile properties of PA6/MCA composites improved. POLYM. COMPOS., 36:892–896, 2015. © 2014 Society of Plastics Engineers     

生物质石墨烯改性聚酰胺6母粒及纤维的制备和性能

介绍了一种生物质石墨烯改性聚酰胺6母粒(GE/PA6母粒)的制备方法,即采用生物质石墨烯粉体、助剂与PA6粉体混合,经过双螺杆挤出机熔融挤出、造粒、干燥,制备得到GE/PA6母粒。该母粒含水率为5×10~(-5),热稳定性得到提高,过滤压力值(FPV)稳定。通过扫描电镜观察生物质石墨烯均匀分散在PA6中,达到纺丝要求。使用该GE/PA6母粒制备的改性锦纶6具有优越的抗菌性,其对金黄色葡萄球菌的抑菌率达到90%,对大肠埃希菌的抑菌率达到85%,对白念珠菌的抑菌率达到82%;同时也具有优异的远红外功能,其远红外发射率为0.88,远红外辐照温升达到2.3℃。     

水滑石对MCA阻燃PA6性能的影响

研究了水滑石对三聚氰胺氰尿酸盐(MCA)阻燃聚酰胺(PA6)的力学性能、热稳定性和阻燃性能的影响,讨论了水滑石在MCA阻燃PA6热分解历程和燃烧过程所发挥的作用。结果表明,随着水滑石用量从0%增加到15%,MCA阻燃PA6复合材料的拉伸强度从73 MPa下降到65 MPa,降幅约11%,冲击强度从40 J/m下降到34 J/m,降幅为15%。随着水滑石用量增加,MCA阻燃PA6的复合材料的热稳定性能下降,但材料的防火性能得到提高,另外,随着水滑石用量从0%增加到15%,M CA阻燃PA6的极限氧指数从32%升高到36%。