纳米Mg(OH)_2-微胶囊红磷/乙烯-乙酸乙烯酯共聚物阻燃复合材料的性能

以微米Mg(OH)_2(mMg(OH)_2)、纳米Mg(OH)_2(nMg(OH)_2)和微胶囊红磷(MRP)为无卤阻燃剂,乙烯-乙酸乙烯酯共聚物(EVA)为聚合物基体,通过熔融共混方法制备了一系列不同阻燃剂含量的Mg(OH)_2-MRP/EVA阻燃复合材料,采用极限氧指数、垂直燃烧、锥形量热分析、热分析、SEM、拉伸试验、流变学分析等方法研究了复合材料的阻燃、力学和加工性能。结果表明,Mg(OH)_2阻燃剂用量相同时,nMg(OH)_2/EVA复合材料的阻燃和抑烟性能比mMg(OH)_2/EVA复合材料更好,但当Mg(OH)_2用量小于60wt%时,nMg(OH)_2/EVA和mMg(OH)_2/EVA复合材料的垂直燃烧等级都达不到V-0级。Mg(OH)_2本身的阻燃效率较低,nMg(OH)_2和MRP对EVA有非常显著的协同阻燃作用,二者掺杂比例适当时可大幅度降低Mg(OH)_2的用量。与nMg(OH)_2/EVA复合材料相比,nMg(OH)_2-MRP/EVA复合材料燃烧时能够生成连续致密的炭层,覆盖在材料表面形成防火屏障,提高其阻燃性能。nMg(OH)_2的热分解反应对nMg(OH)_2-MRP/EVA复合材料的燃烧性能有极其重要的影响。当nMg(OH)_2热分解后再加入到MRP/EVA体系中时,nMg(OH)_2-MRP/EVA复合材料的阻燃和抑烟性能均急剧降低。当nMg(OH)_2∶MRP∶EVA的质量比为40∶10∶100时,nMg(OH)_2-MRP/EVA复合材料同时具有优异的阻燃性能、力学性能和加工性能,可满足实际应用的需要。     

线性低密度聚乙烯的无卤协同阻燃及抑烟性能表征

在研究了氢氧化铝(ATH)与氢氧化镁(MH)复配阻燃线性低密度聚乙烯(LLDPE)的基础上,重点研究微胶囊红磷(MRP)、MRP和硼酸锌(ZB)复合在LLDPE/ATH/MH中的协同阻燃及抑烟作用。燃烧性能研究表明,MRP在LLDPE/ATH/MH复配体系中有良好的协同阻燃效果;MRP与ZB复合能够更好地发挥协同阻燃作用,复配阻燃剂添加量为93phr时,LLDPE/ATH/MH/MRP/ZB体系的LOI值高达38.1%,最大烟密度(Dm)为53。热失重分析和光电子能谱分析表明,协同阻燃抑烟作用以凝聚相交联成炭为主。     

三聚氰胺磷酸盐和季戊四醇在EVA中的阻燃研究

研究了三聚氰胺磷酸盐(M P)和季戊四醇(PER)作为膨胀型阻燃剂(IFR)在乙烯-醋酸乙烯酯共聚物(EVA)中的阻燃作用。采用氧指数法和垂直燃烧法研究了M P和PER不同配比对EVA阻燃效果的影响。实验结果表明,M P和PER的配比不同对体系的阻燃有很大影响。在M P和PER总添加量为50%时,M P/PER质量比为2∶1时显示出最好的阻燃效果,阻燃EVA体系氧指数最高,垂直燃烧达到V-0级。采用热分析研究了膨胀型阻燃EVA体系的热分解特性,以及采用激光拉曼光谱等手段对材料燃烧后形成的膨胀炭层进行了表征。     

苯并噁嗪与微胶囊红磷及丁腈橡胶对ABS的阻燃增韧

采用苯并噁嗪(BOZ)与微胶囊化红磷(MRP)复配制备了无卤阻燃丙烯腈-丁二烯-苯乙烯共聚物(ABS)。研究了BOZ/MRP质量比和用量对阻燃ABS性能的影响。然后固定BOZ和MRP的用量,考察丁腈橡胶(NBR)的添加量对BOZ/MRP/ABS阻燃体系阻燃性能和力学性能的影响。结果表明,BOZ/MRP质量比为3:2,总量为20%(质量分数)时,可制得氧指数(LOI)达24.4%,垂直燃烧达UL-94 V-0级的无卤阻燃ABS;BOZ受热产生的酚羟基与红磷燃烧产生的氧化磷等发生酯化反应减缓了ABS的分解;NBR添加量为8%时,阻燃体系垂直燃烧达V-0级,拉伸强度为30.8 MPa,缺口冲击强度达11.4 kJ/m2。     

PE/木粉/MRP/Nano–MH共混材料的阻燃及热分解动力学研究

目的 研究微胶囊红磷(MRP)和纳米氢氧化镁(Nano–MH)协同阻燃木塑复合材料(WPC)的阻燃效果及阻燃机理。方法 以MRP为主阻燃剂,Nano–MH为协效阻燃剂,低密度聚乙烯(LDPE)、线型低密度聚乙烯(LLDPE)和木粉为基础物质,采用二次造粒和注射成型法制备阻燃木塑材料(WPC/MRP/MH)。通过燃烧等级测定、极限氧指数(LOI)测定和热重谱图(TG)分析阻燃剂对复合材料阻燃性的影响,利用Flynne–Walle–Ozawa(FWO)方法研究WPC和WPC/MRP/MH的热分解行为,并采用Criado方法推断WPC/MRP/MH的反应机理。结果 复合材料MRP质量分数为12.5%时阻燃等级达到UL94 V–0级,LOI值高达28.3%;WPC/MRP/MH的t_onset、t_endset和t_p均高于WPC,且在热分解后期FWO方法得到的表观活化能(E_a)逐渐增加,材料热稳定性明显提高;WPC/MRP/MH的反应机理函数为g(α)=[-ln(1-α)]^1/n、f(α)...     

改性氢氧化镁的制备及在PA66中的阻燃应用

以氯化镁、氢氧化钠、尿素和硬脂酸钠为原料,采用沉淀法制备出改性氢氧化镁(MH)粉末材料。结果表明,制备的MH为无规则的、粒径为30～120nm的,且至少有一维是纳米结构的片状材料。在应用方面,采用熔融挤出法制备了多组不同配方的尼龙66(PA66)复合材料。研究发现,MH单独使用时阻燃效率低,将它与微胶囊红磷(MRP)复配使用后能有效地提高材料的阻燃性能。当x(PA66)∶x(MRP)∶x(MH)=100(phr)∶10(phr)∶8(phr)时,MRP/MH/PA66复合材料的垂直燃烧为V-0级,LOI能达到32%。此外,还探讨了可能的阻燃机理,并通过TG、TG-MS等手段研究了材料的热氧稳定性及热氧分解气态产物。     

纳米SiO_2协效纳米Mg(OH)_2阻燃EVA的研究

以纳米二氧化硅(SiO_2)为协效剂,协效纳米氢氧化镁(MH)阻燃乙烯-醋酸乙烯酯(EVA),并制得纳米SiO_2/MH/EVA复合材料。采用傅里叶红外光谱仪(FT-IR)、热重分析仪(TG)、扫描电子显微镜(SEM)、氧指数和垂直燃烧测定法对材料的性能进行测试。结果表明:纳米SiO_2与纳米MH间有明显的协同作用,SiO_2含量为6%(wt,质量分数),MH为44%(wt,质量分数),制得的纳米SiO_2/MH/EVA复合材料的阻燃体系氧指数为30.8%,阻燃等级为V-0级,断裂伸长率达到726%,拉伸强度达到3.82MPa。SiO_2/MH在EVA中分散优于纳米MH,纳米SiO2可以有效改善复合材料的力学性能和阻燃性能。     

微胶囊化膨胀型阻燃剂与有机蒙脱土协效阻燃乙烯-醋酸乙烯共聚物性能

通过纳米复合的方式,将微胶囊化的膨胀型阻燃体系—聚磷酸铵(APP)-季戊四醇(PER)与有机改性的片层蒙脱土(OMMT)用于协效阻燃乙烯-醋酸乙烯共聚物(EVA)。采用XRD、TEM、TGA、极限氧指数(LOI)、垂直燃烧(UL-94)、锥形量热仪、烟密度和动态机械热分析对微胶囊化APP(MCAPP)-微胶囊化PER(MCPER)-OMMT/EVA复合材料的结构与性能进行研究。研究结果表明,OMMT被完全剥离开,并以层离或插层的状态分散在EVA中;MCAPP-MCPER与OMMT之间存在明显的协效阻燃作用,用3wt%OMMT代替MCAPP-MCPER后,MCAPP-MCPER-OMMT/EVA复合材料的LOI值从25.5vol%提高到29.5vol%,垂直燃烧结果由V-2上升到V-0级别,残炭量也由14.5wt%增大到15.9wt%,烟密度由154.7 g/s降低到97.5 g/s,材料的阻燃性能得到有效提高。此外,万能拉伸测试及动态机械热分析测试表明,通过纳米复合制备的阻燃MCAPP-MCPER-OMMT/EVA复合材料具有更好的力学和动态热机械性能。      

膨胀阻燃剂对EVA阻燃和力学性能的影响

以聚磷酸铵(APP)、三嗪系成炭发泡剂(CFA)和4A分子筛(4AZEO)作为乙烯-醋酸乙烯酯共聚物(EVA)的膨胀阻燃剂(IFR)。采用氧指数、垂直燃烧研究了APP与CFA的不同配比、IFR不同添加量对阻燃材料阻燃性能的影响,并对其力学性能进行测试。当IFR总添加量为28%,APP/CFA质量比为3∶1时阻燃EVA材料显示出较好的阻燃效果,其氧指数为33.8,垂直燃烧达到UL-94V0级。采用热失重法证实了配比合理的膨胀阻燃剂能够促进EVA在高温时的成炭,最后采用扫描电镜法对残炭外貌进行了表征。     

阻燃聚合物/层状双氢氧化物复合材料的研究进展

层状双氢氧化物(LDH)是一种典型的无机超分子材料,被广泛应用于催化、药物载体、聚合物阻燃等领域,近年来受到了人们的广泛关注.在综述LDH阻燃机理的同时,结合本课题组的研究工作,时LDH的规模化制备、高效阻燃体系开发及LDH与聚合物相容性影响因素进行了详细阐述,并提出了LDH作为阻燃荆的研究和应用趋势以及需要解决的关键问题.     

增容剂EVA-g-MAH对乙烯-醋酸乙烯共聚物/聚酰胺6阻燃合金性能的影响

采用熔融共混法,以聚磷酸铵(APP)、季戊四醇(PER)为原料组成的膨胀阻燃剂(IFR),制备了乙烯-醋酸乙烯共聚物/聚酰胺6/IFR(EVA/PA6/IFR)阻燃复合材料,并研究了增容剂EVA-g-MAH对EVA/PA6阻燃合金阻燃性和力学性能的影响。通过极限氧指数、垂直燃烧、熔融指数、力学性能、热重分析和扫描电子显微镜等手段对EVA/PA6阻燃合金进行了性能测试与表征。结果表明:随着EVA-g-MAH用量的增加,EVA/PA6阻燃合金的极限氧指数稍有降低,但当EVA-g-MAH质量分数为10%时,垂直燃烧可达UL 94V-0级;拉伸强度和断裂伸长率随着增容剂含量的增加而逐渐升高。热重分析结果表明,增容剂可提高EVA/PA6阻燃合金的热稳定性。     

无卤阻燃乙烯-醋酸乙烯酯共聚物泡沫复合材料的制备及性能表征

为使得乙烯-醋酸乙烯酯共聚物(EVA)泡沫复合材料具有阻燃功能,分别添加膨胀石墨-聚磷酸铵(EGAPP)和膨胀石墨-聚磷酸铵-热塑性淀粉(EG-APP-TPS)两种不同复配阻燃剂,通过熔融共混和硫化发泡制备了无卤阻燃EVA泡沫复合材料。采用极限氧指数(LOI)、垂直燃烧(UL-94)、热分析质谱联用(TG-MASS)及扫描电镜(SEM)测试等对EG-APP/EVA及EG-APP-TPS/EVA泡沫复合材料进行表征。结果表明:EG-APP复配阻燃剂添加量为30wt%、EG与APP质量比为1∶4时,EG-APP/EVA泡沫复合材料的LOI达28.1%,UL-94为V-1级;而当EG-APP-TPS复配阻燃剂添加量同为30wt%,EG、APP与TPS质量比为1∶4∶1时,EG-APP-TPS/EVA泡沫复合材料的LOI可达29.3%,UL-94为V-0级。TG-MASS和SEM分析表明:EG、APP和TPS在气相和固相中均具有显著的协同阻燃作用。     

Preparation of silane precursor microencapsulated intumescent flame retardant and its enhancement on the properties of ethylene–vinyl acetate copolymer cable

Silane precursor microencapsulated intumescent flame retardant (IFR) was prepared by sol–gel process and then modified with vinyltrimethoxysilane (A-171) with the goal of that the vinyl group functionalized silica microcapsule could be introduced into EVA matrix through crosslinking, which will enhance the compatibility and dispersion between EVA matrix and microencapsulated IFR. The effects of silane precursor microencapsulation technology on the mechanical, electrical, thermal, interfacial adhesion and flame retardant properties of intumescent flame-retardant EVA cable were investigated by mechanical test, resistance meter, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), limiting oxygen index (LOI) and UL-94 test. The Fourier transform infrared (FTIR) results indicated silane precursor microencapsulated IFR were successfully prepared, and the water contact angle (WCA) results indicated that silane precursor results in the transformation of hydrophilic to hydrophobic of IFR surface. The characterization for the various properties of EVA composites demonstrated that silane precursor microencapsulation technology enhanced the interfacial adhesion, mechanical, electrical, thermal stability and flame retardancy of EVA/MCAPP/MCPER system. Furthermore, the water resistance test results demonstrate that EVA/MCAPP/MCPER composites have good water durability. This investigation provides a formulation for the industrial application as insulated materials of EVA cable with excellent properties.     

微胶囊Mg (OH)2的合成及其对乙烯-乙酸乙烯酯共聚物的阻燃作用

用原位聚合方法合成了以微米Mg（OH）₂粒子为芯材、交联聚脲为壁材的微胶囊Mg（OH）₂（M-Mg（OH）₂）阻燃剂,并把M-Mg（OH）₂加入到乙烯-乙酸乙烯酯共聚物（EVA）中,研究了M-Mg（OH）₂对EVA的阻燃作用。采用FTIR、SEM、热分析和酸滴定方法研究了M-Mg（OH）₂的性质,用极限氧指数（LOI）和垂直燃烧方法（UL-94）研究了M-Mg（OH）₂/EVA复合材料的阻燃性能以及酸腐蚀对M-Mg（OH）₂/EVA复合材料阻燃性能的影响。结果表明,采用原位聚合方法能够成功地在Mg（OH）₂粒子表面包覆交联聚脲壁材,得到M-Mg（OH）₂。与纯Mg（OH）₂相比,M-Mg（OH）₂的颗粒尺寸增大,热稳定性增加,在水中溶解度显著降低,在EVA基体中分散更加均匀。阻燃剂用量相同时,M-Mg（OH）₂/EVA复合材料的LOI总是比Mg（OH）₂/EVA复合材料的数值稍大。阻燃剂与EVA质量比小于135∶100时,两种复合材料的垂直燃烧级别均为V-2级,阻燃剂与EVA质量比在135∶100~150∶100之间时,前者的燃烧级别为V-0级,而后者只能达到V-2级,阻燃剂与EVA质量比超过150∶100时,两种复合材料都能达到V-0级。M-Mg（OH）₂/EVA复合材料的耐酸性比Mg（OH）₂/EVA大幅度提高,可以在酸性环境中使用。     

阻燃增效剂对ATH/EVA纳米复合材料性能的影响

采用熔融共混挤出法制备纳米氢氧化铝（ATH）为主体的阻燃乙烯-醋酸乙烯共聚物（EVA）材料，研究了阻燃增效剂纳米有机蒙脱土（OMMT）与硼酸锌（ZnB）对复合材料阻燃、力学与电学性能的影响.TEM、TG与FT-IR检测表明，OMMT在基体中插层状分散，不仅提高了材料的拉伸强度，而且在燃烧过程中具有显著的促进基体成炭作用;少量ZnB的加入有效制止了阴燃，此时材料综合性能达到使用要求。     

硅油对EVA/ATH复合材料的协同阻燃作用

采用氧指数、锥形量热仪等手段,研究了羟基硅油（HSO）在乙烯-醋酸乙烯酯（EVA）/氢氧化铝（ATH）体系中的协效阻燃作用。氧指数结果表明,随着HSO添加量的增加,复合材料的氧指数略有所下降,样品EVA1～EVA5的氧指数从31下降至27.5。锥形量热仪结果表明,随着HSO添加量的增加,复合材料的热释放速率峰值呈明显的...     

Cyclodextrin microencapsulated ammonium polyphosphate: Preparation and its performance on the thermal,flame retardancy and mechanical properties of ethylene vinyl acetate copolymer

Cyclodextrin microencapsulated ammonium polyphosphate (MCAPP) was prepared by the reaction between cyclodextrin (CD) and toluene-2,4-diisocyanate (TDI) with the goal of improving the water durability of APP and preparing a novel functional flame retardants. The Fourier transform infrared spectra (FTIR) and X-ray photoelectron spectroscopy (XPS) results indicated MCAPP were successfully prepared, and the water contact angle (WCA) results indicated that cyclodextrin resulted in the transformation of hydrophilic to hydrophobic of the flame retardant surface. The MCAPP was then incorporated into the ethylene vinyl acetate copolymer (EVA) system and the effects of the MCAPP on the mechanical, combustion, thermal, interfacial adhesion and flame-retardant properties of EVA cable were investigated and compared by thermogravimetric analysis (TGA), scanning electron microscopy (SEM), limiting oxygen index (LOI), mechanical test, cone calorimeter and UL-94 test. The characterization for the various properties of EVA composites demonstrated that cyclodextrin microencapsulation technology could enhance the interfacial adhesion, resulting in the improved mechanical, thermal stability, combustion properties and flame-retardant properties compared with those of EVA/APP/CD system. Furthermore, the water resistance experiments results demonstrate that EVA/MCAPP composites have good water durability due to the hydrophobic property of MCAPP. Above all, the microencapsulation of APP with cyclodextrin developed in this study may be a promising formulation for combining the acid source, the carbonization agent and the blowing agent in one flame retardant, and the MCAPP can solve the water resistance and the compatibility problem of the flame retardant during the industrial application.     

Effect of cellulose acetate butyrate microencapsulated ammonium polyphosphate on the flame retardancy, mechanical, electrical, and thermal properties of intumescent flame-retardant ethylene-vinyl acetate copolymer/microencapsulated ammonium polyphosphate/polyamide-6 blends

Ammonium polyphosphate (APP), a widely used intumescent flame retardant, has been microencapsulated by cellulose acetate butyrate with the aim of enhancing the water resistance of APP and the compatibility between the ethylene-vinyl acetate copolymer (EVA) matrix and APP. The structure of microencapsulated ammonium polyphosphate (MCAPP) was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and water contact angle (WCA). The flame retadancy and thermal stability were investigated by a limiting oxygen index (LOI) test, UL-94 test, cone calorimeter, and thermogravimetric analysis (TGA). The WCA results indicated that MCAPP has excellent water resistance and hydrophobicity. The results demonstrated that MCAPP enhanced interfacial adhesion, mechanical, electrical, and thermal stability of the EVA/MCAPP/polyamide-6 (PA-6) system. The microencapsulation not only imparted EVA/MCAPP/PA-6 with a higher LOI value and UL-94 rating but also could significantly improve the fire safety. Furthermore, the microencapsulated EVA/MCAPP/PA-6 composites can still pass the UL-94 V-0 rating after treatment with water for 3 days at 70 °C, indicating excellent water resistance. This investigation provides a promising formulation for the intumescent flame retardant EVA with excellent properties.