ZnO与Al(OH)3在阻燃软PVC中的协同阻燃消烟作用

研究了ZnO和Al(OH)3复合阻燃剂对软PVC的协同阻燃消烟作用.通过热分析的方法研究了阻燃处理后的软PVC从室温到800℃的热降解过程,用Kissinger方程给出了热降解反应的活化能,通过剩炭率的测定以及用电子扫描显微镜(SEM)对燃烧后所生成炭层的观察探讨了协同体系阻燃抑烟的机理.结果表明经阻燃处理的样品具有较高的极限氧指数(LOI)、剩炭率较低的烟密度等级(SDR)和最大烟密度(MSD),与未处理的样品相比具有较好的阻燃和消烟性能.加入适量的ZnO与Al(OH)3复合使用可明显地提高软PVC的LOI和剩炭率,降低材料的SDR和MSD.ZnO的加入可改变PVC的热降解过程,使起始降解温度降低并且使反应的活化能增大,可能属于固相Lewis酸催化机理.     

系列羟基锡酸盐对半硬质PVC的阻燃消烟作用

研究了系列羟基锡酸盐阻燃剂对半硬质PVC的阻燃消烟作用。通过对样品燃烧后剩炭含量及扫描电镜(SEM)分析,探讨了锡酸盐体系阻燃抑烟的机理。结果表明:经阻燃处理的样品具有较高的极限氧指数(LOI)和剩炭率,较低的烟密度等级(SDR)和最大烟密度(MSD),与未处理的样品相比具有较好的阻燃和消烟性能。由于阻燃剂的添加量较少,对材料力学性能影响不大。     

SnO2与氢氧化物复合阻燃剂对软PVC的阻燃消烟作用

研究了SnO2和无机氢氧化物阻燃剂对软PVC的阻燃消烟作用。通过热分析的方法研究了阻燃处理后的软PVC从室温到800℃的热降解过程,通过剩炭率的测定以及用电子扫描显微镜(SEM)对燃烧后所生成炭层的观察探讨了不同体系的阻燃抑烟的机理。结果表明:经SnO2和氢氧化物复合阻燃处理的样品具有较高的极限氧指数(LOI)和剩炭率,烟密度等级(SDR)和最大烟密度(MSD)明显降低,与未处理的样品相比具有较好的阻燃和消烟性能。SnO2的加入可改变PVC的热降解过程,使起始降解温度降低,SnO2可能是在凝聚相和气相同时起作用,但主要是在凝聚相起Lewis酸催化作用。     

金属配合物对软聚氯乙烯的阻燃消烟作用

利用热分析的方法研究了以Al(OH)3和Mg(OH)2为基础，含有Fe、Co、Ni或Cu的金属配合物的复合阻燃剂对软聚氯乙烯(PVC)的阻燃消烟作用。研究了软PVC从室温到1073K的热降解过程。利用Kissinger方程给出了其动力学参数。结果表明：阻燃处理过的软PVC具有较好的阻燃消烟性能，如较高的氧指数和剩炭率，较低的烟密度等级和最大烟密度，力学性能有所降低。     

羟基锡酸锌包覆硫酸钡的制备以及在软PVC中的阻燃应用

通过均匀沉淀法制备了羟基锡酸锌包覆硫酸钡(ZHSCB)样品,并与硫酸钡(BaSO4)对比应用于软PVC的阻燃消烟处理。利用X-射线衍射(XRD)及扫描电子显微镜(SEM)等手段对ZHSCB进行了表征,并通过极限氧指数(LOI)和烟密度等级(SDR测试)研究了ZHSCB对PVC的阻燃消烟作用。通过热分析的方法研究了阻燃PVC从室温到800℃的热降解过程。通过拉伸强度和断裂伸长率测定了ZHSCB对PVC的力学性能的影响。结果表明:ZHSCB对PVC有优异的阻燃消烟作用,能够有效促进PVC第一降解阶段的脱HCl反应,促进交联成炭反应的进行以及剩炭稳定性的提高,并且对于PVC的力学性能影响较小。     

羟基锡酸三聚氰胺盐及羟基锡酸金属盐复合物阻燃PVC的阻燃性能及热性能研究

合成了四种羟基锡酸三聚氰胺盐及羟基锡酸金属盐复合物,并作为新型膨胀阻燃剂应用于软聚氯乙烯(PVC)的阻燃消烟处理。极限氧指数(LOI)及烟密度等级(SDR)测试表明,这些复合物是软PVC有效的阻燃消烟剂。利用热重分析(TGA)、差热分析(DTA)并结合扫描电子显微镜(SEM)研究了阻燃PVC的热降解过程。结果表明:这些复合物不但能够在降解第一阶段降低PVC的起始分解温度,提高失重速率,而且能够促进PVC在第二阶段生成膨胀型的炭层。     

SnO2和SiO2用于PVC的阻燃消烟及协同作用

研究了二氧化锡和二氧化硅对软PVC阻燃消烟性的影响。通过对极限氧指数、剩炭率、烟密度的测定和DTATG曲线的分析证明,添加8g二氧化锡/二氧化硅复合阻燃剂的PVC的氧指数和剩炭率比未添加的分别增高5.5个单位和4.1%,烟密度降低16.4%,降解活化能分别降低38kJ/mol和23.1kJ/mol,从而证明二氧化锡/二氧化硅复合阻燃剂对于PVC是一种很好的阻燃消烟剂,二氧化锡和二氧化硅有很好的协同作用。同时证明这种复合阻燃剂能代替三氧化二锑,使产品的成本进一步降低。     

模板法合成锡酸钴及其对PVC的阻燃应用

以活性炭为模板、五水四氯化锡和六水硝酸钴为原料,制备纯相的多孔锡酸钴（CoSnO3）阻燃剂,通过X射线衍射（XRD）和扫描电镜（SEM）对其结构、形貌进行表征,并将其应用于PVC的阻燃研究中。当CoSnO3的添加量为15份时,其极限氧指数（LOI）达到35.6％、烟密度等级（SDR）为75.2％、断裂伸长率为168.32%、拉伸强度为 22.50 MPa。通过热重分析（TGA）对阻燃前后PVC的热降解行为进行了初步探讨,研究发现： 经CoSnO3阻燃处理后,PVC样品的初始降解温度降低,高温时的剩炭量增加,表明CoSnO3对PVC材料具有较好的阻燃消烟性能。     

高分子粘结膜与金属化合物对PVC树脂的协同阻燃消烟作用

研究了铝塑复合板中高分子粘结膜与Mg(OH)_2和CaCO_3复合阻燃剂对PVC树脂的协同阻燃消烟作用。通过NBS烟箱等仪器测试的有关参数对PVC体系中的金属化合物及填料的抑烟、阻燃效果进行了分析和研究。结果表明：在高分子粘结膜和金属化合物协同作用下能使烟密度(MSD)和生烟速率显著降低,而且有效地推迟了发烟时间。各种金属化合物对PVC体系的氧指数(LOI)影响不大,对烟密度的影响差异很大。     

LaFeO_3的合成及其在软质PVC中的阻燃应用

采用高温煅烧法合成了钙钛矿型铁酸镧(LaFeO3)。探讨了煅烧温度及时间对反应产物的影响,通过X射线衍射(XRD)对LaFeO3进行了表征,确定高温煅烧的最佳条件为800℃下煅烧4 h。通过极限氧指数(LOI)、烟密度等级(SDR)及锥形量热(CONE)测试研究了LaFeO3对软质PVC阻燃及消烟性能的影响,使用热重分析(TGA)考察了LaFeO3对PVC热降解过程的影响。结果表明:LaFeO3能有效地降低PVC燃烧过程中的发烟量,使样品燃烧的热释放速率(HRR)、烟释放速率(SPR)以及总烟释放量(TSP)等明显降低;LaFeO3主要在PVC降解的第二阶段发挥阻燃消烟作用,大量稳定的残炭的生成是LaFeO3具有优异消烟性能的主要原因。     

Metal chelates as synergistic flame retardants for flexible PVC

The thermal degradation of flexible PVC treated with various metal chelates containing Cr, Al, Fe, Co, Ni, Cu, or Zn combined with two compounds, Al(OH)₃ and Mg(OH)₂, was studied by thermal analysis. Limiting Oxygen Index (LOI), Smoke Density Rating (SDR), and mechanical properties were investigated. The structure of the char formed after combustion of the PVC compounds was observed through scanning electron microscopy (SEM). The high LOI and char yield of flexible PVC treated with flame retardants showed that there was a good synergistic effect between Al(OH)₃, Mg(OH)₂, and metal chelates. J. VINYL. ADDIT. TECHNOL., 11:70–75, 2005. © 2005 Society of Plastics Engineers.     

Metal hydroxystannates as flame retardants and smoke suppressants for semirigid poly(vinyl chloride)

Metal hydroxystannates were studied as flame retardants and smoke suppressants for semirigid poly(vinyl chloride) (PVC). The flame‐retardant and smoke‐suppression mechanisms were investigated by using limiting oxygen index (LOI), smoke density rating (SDR), the solid yield test (SY), scanning electron microscopy (SEM), thermogravimetry, differential thermogravimetry, and differential thermal analysis. Results showed that semirigid PVC treated with the flame retardants had a higher LOI, and solid yield, but a lower SDR and maximum smoke density, thereby indicating that the flame‐retardance and smoke‐suppression properties of the treated PVC were improved and that the hydroxystannate compounds could be used as highly effective flame retardants. The tin compounds may exert their action in both the condensed and vapor phases, but mainly in the condensed phase as Lewis acids. J. VINYL ADDIT. TECHNOL., 2008. © 2008 Society of Plastics Engineers.     

Zn2SnO4的制备及其对软质聚氯乙烯的阻燃研究

以结晶四氯化锡和硝酸锌为原料,通过2步煅烧法制备锡酸锌(Zn2SnO4)阻燃剂;通过极限氧指数、烟密度等级和残炭量研究了Zn2SnO4对软质聚氯乙烯（PVC）的阻燃和消烟性能的影响,同时对力学性能进行了研究。结果表明,Zn2SnO4的用量为15份时,对软质PVC的阻燃消烟效果明显,其极限氧指数可达36.0 %、烟密度等级为86.2 %、残炭率为29.7 %、拉伸强度为25.47 MPa、断裂伸长率为168 %;利用热重分析、差热分析和扫描电子显微镜等方法对阻燃PVC进一步进行表征,结果表明Zn2SnO4的加入促使软质PVC的起始分解温度降低,残炭量增加,燃烧后剩炭结构致密,阻燃效果明显。     

活性炭模板制备铝酸铁及其在软PVC中的阻燃应用

以硫酸铁和硫酸铝为原料,以磷酸处理过的活性炭为模板制备铝酸铁阻燃剂。并通过X射线衍射（XRD）和红外吸收光谱（FT-IR）对合成铝酸铁阻燃剂做了表征。用极限氧指数、烟密度测试其对PVC的阻燃消烟性,当铝酸铁阻燃剂的添加量为5%（质量分数）时,阻燃后软PVC的极限氧指数达到32.8%,烟密度等级为55.45%,拉伸强度为18.36 MPa,断裂伸长率为214%,并通过热重分析对阻燃前后PVC的热降解行为做了研究。结果表明：以活性炭为模板制备的铝酸铁阻燃剂对软质PVC具有较好的阻燃消烟性能。     

Flame retardant flexible poly(vinyl chloride) compound for cable application

ZnO/MgO, ZnO/CaO, and ZnO/CaO/MgO can form solid solutions. The solid solution for we as flame retardant (SSFR) was obtained by annealing at 1023 K for 4.5 h in a muffle furnace. Flexible poly (vinyl chloride) (PVC) filled with SSFR and Sb₂O₃ was investigated by differential thermal analysis thermogravimetry. Limiting oxygen index (LOI), mechanical properties, and electrical properties were studied. The surface of the char formed after combusting of the PVC compounds was observed through scanning electron microscopy and the effect of the surface area to the LOI was also studied. The data suggested that a small amount of SSFR and Sb₂O₃ have good synergy and can greatly increase the LOI and the char yield, and that the thermal degradation temperature and the activation energy decreased. It can be concluded that the mechanism of SSFR is a condensed‐phase mechanism. Moreover, one can conclude that the surface area can enhance the LOI. All the results showed that SSFR is effective and safe as a flame retardant in flexible PVC. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3137–3142, 2003     

Low‐melting sulfate glasses as additives to semirigid PVC and their flame retardant and smoke suppressant properties

The role of low‐melting sulfate glasses (LMSG) as additives on the flame retardant and smoke suppressant properties of semirigid poly(vinyl chloride) (PVC), as well as the mechanism for flame retardancy and smoke suppression, were studied through the Limiting Oxygen Index (LOI) test. Smoke Density Rating (SDR) test, DTA‐TG, and SEM. The results show that the LMSG have good smoke suppressant properties. When the PVC compound contains 40 parts of LMSG, the SDR value will be reduced by about 45%. The Cu²⁺, Zn²⁺, Mn²⁺, and Ni²⁺ sulfates, as well as MoO₃, cause PVC to crosslink and form char, and the melt can protect not only the char formed during combustion and thermal degradation, but also undecomposed polymer. That is the main mechanism for flame retardation and smoke suppression when the additives melt. The mechanical properties of the PVC compounds containing different levels of LMSG were also studied.