二苯砜磺酸钾阻燃PC的热降解行为及老化寿命估算

采用氧指数法测试了二苯砜磺酸钾(KSS)的阻燃性能,并运用热重(TG)分析结合Kissinger和Flynn-Wall-Ozawa处理方法对KSS阻燃聚碳酸酯(PC)的非等温降解动力学和热老化寿命进行了研究.结果表明,阻燃剂的加入可大幅度提高PC的阻燃性能,当KSS的质量分数为0.7%时,阻燃PC的氧指数可从纯PC的26.3%增加到34.4%,阻燃等级由FV-2级提高到FV-0级;KSS的加入改变了PC的热降解活化能,相对于纯PC的活化能为186.54 kJ/mol,阻燃PC的降解活化能只有171.41 kJ/mol,表明KSS的加入促进了热降解,有利于在材料的燃烧表面快速地形成炭层,起到阻燃作用;阻燃荆的加入使同一温度下PC的不同失重率所对应的时间缩短,即热稳定性降低,这一点与阻燃剂能够降低PC的初始降解温度、提前分解成炭有密切关系.     

SNP阻燃剂对聚碳酸酯热分解与老化寿命的影响

采用热重(TG)分析法研究了不同升温速率下,SNP阻燃剂对聚碳酸酯(PC)热降解行为的影响,并且通过Kissinger和Flynn-Wall-Ozawa两种方法对PC/SNP复合材料的热分解动力学进行了探讨,两种方法计算结果一致,均表明阻燃剂SNP的加入降低了PC的热分解活化能,相比PC分别降低了9.9%和9.0%。采用时–温等效原理对阻燃PC的老化寿命进行了预估,结果发现,SNP阻燃剂的加入使PC的老化寿命明显缩短,表明SNP阻燃剂能加快PC的热降解速率,使PC的初始分解温度提前了6.46%,促使PC更早地降解成炭,成炭量增加了28%,从而提高了PC的阻燃性能。     

甲基三硼硅烷对PET热性能和阻燃性能的影响

以硼酸和甲基三甲氧基硅烷为原料合成一种硼硅化合物甲基三硼硅烷,通过傅立叶变换红外光谱和热重(TG)分析确定其化学结构和热性能。TG分析数据表明,新型阻燃剂甲基三硼硅烷在氮气气氛和空气气氛中都有很好的热稳定性。将其以熔融共混的方法应用于聚对苯二甲酸乙二酯(PET)的阻燃研究,通过TG分析阻燃PET的热性能,实验表明,阻燃剂甲基三硼硅烷的加入可使PET的失重过程向高温推移,提高质量保持率。采用极限氧指数(LOI)和垂直燃烧测试(UL94)判定阻燃剂对PET的阻燃效果。当阻燃剂的质量分数仅为3%时,阻燃PET的LOI能达34.3%,UL94等级可达V–0级,自熄能力较好。     

热塑性酚醛树脂／磷酸三苯酯对PC阻燃性能的研究

分别合成了三种不同摩尔质量的热塑性酚醛树脂(PF),并将其分别与磷酸三苯酯(TPP)复配作为阻燃剂,制备了一系列的PF/TPP/PC阻燃体系,通过极限氧指数(LOI)、热失重(TGA)测试,研究了酚醛树脂摩尔质量、阻燃体系各组分配比、阻燃剂用量对聚碳酸酯(PC)阻燃性能的影响.结果表明:PF与仰对PC有良好的协同阻燃作用.当TPP/PF质量比为1:1,总添加量为20%时,PC的极限氧指数可达46%～52%.TGA曲线显示,在降解过程中酚醛树脂的加入能有效地抑制TPP的挥发,提高了PC在降解过程中的热稳定性并促使了更多炭层的形成.     

ADP协效无卤阻燃对硅烷交联LLDPE/LDPE/POE性能的影响

硅烷交联无卤阻燃聚烯烃电缆料易吸潮预交联,以及氢氧化镁(MH)与氢氧化铝(ATH)阻燃剂添加量大而导致挤出性差,针对此问题,文章将MH/ATH阻燃剂硅烷偶联处理后,然后将其与阻燃协效剂二乙基次膦酸铝(ADP)以及硅烷交联聚烯烃熔融共混,制备了硅烷交联LLDPE/LDPE/POE无卤阻燃材料,重点研究了阻燃剂硅烷处理以及阻燃协效剂ADP的添加对其加工性能的影响,此外,研究了ADP的添加量对阻燃剂偶联处理后的复合材料氧指数、力学性能、热延伸性能的影响。结果表明:阻燃剂偶联处理以及ADP的添加使挤出的复合材料片材平整光滑,没有预交联;此时,平衡扭矩下降了2. 1 N·m,熔体流动速率提高了0. 12 g/10 min。随着ADP添加量的增加,氧指数、拉伸强度、断裂伸长率呈先上升后下降趋势,热延伸率和永久变形率呈先降低后升高的趋势; ADP加入量为3%(质量分数)时,经过8 d耐水性实验,复合材料的性能最佳,此时,材料的氧指数为33%,热延伸率为16. 8%,永久变形率为6. 6%,拉伸强度为14. 7 MPa和断裂伸长率为364. 8%。     

新型含磷阻燃剂的制备及在环氧树脂体系中的应用

本文以三氯氧磷、对羟基苯甲醛及DOPO为原料成功合成了一种新型含磷阻燃剂DOPO-TPPO,采用FTIR测试对其结构进行了表征。通过热重分析测试(TGA)研究了产物的热稳定性、热降解行为及成炭性能,表明该阻燃剂具有较好的热稳定性和成炭性能。将阻燃剂DOPO-TPPO添加到环氧树脂中,以二氨基二苯硫砜(DDS)为固化剂制备阻燃环氧树脂固化物,通过极限氧指数(LOI)和垂直燃烧(UL-94)测试研究了环氧树脂固化物的阻燃性能。结果表明:合成产物的起始热分解温度为195℃,在700℃时的残炭量为29%,当阻燃剂添加量(质量分数)为11.0%时,环氧树脂固化物能通过垂直燃烧UL-94 V-0级,氧指数高达32.0%,表明该物质对环氧树脂材料具有优异的阻燃性能。     

S–N–P阻燃剂对聚碳酸酯性能影响研究

采用S–N–P阻燃剂通过熔融共混法制备了阻燃聚碳酸酯(PC)材料,通过极限氧指数(LOI)仪、垂直燃烧仪、万能电子试验机、冲击试验机和热重(TG)分析仪分别研究了阻燃PC的阻燃性能、力学性能和热性能。结果表明,S–N–P阻燃剂能显著提高PC的阻燃性能,当其质量分数为0.1%时,阻燃PC的LOI值达到35.5%,与纯PC相比提高了43.15%,能通过UL 94 V–0等级,同时拉伸强度相比纯PC提高了17.35%,弯曲强度提高了36.7%,断裂伸长率提高了121.6%,缺口冲击强度仅降低了7.63%;TG分析表明S–N–P阻燃剂能加速PC降解,从而加速炭层的形成起到阻燃作用。     

磷化酚醛树脂的合成及其阻燃性能研究

以苯酚,三氯氧磷(POCl3),热塑性酚醛树脂(FR)为原料,三乙胺(Et3N)为缚酸剂合成了一种新型的含磷阻燃剂-磷化酚醛树脂(FR-P),采用红外光谱(FT IR),核磁共振磷谱(31PNMR),电感耦合等离子体发射光谱(ICP)及热重分析(TG)对聚合物的结构及热性能进行了表征,探讨了合成中的各因素对反应的影响,得出了最佳的合成工艺条件,并将合成的化合物用于PC的阻燃,采用热分析法、极限氧指数法(LOI)对阻燃体系的热性能和阻燃性能进行了表征,并与PC/FR阻燃体系进行了比较。研究结果表明,FR-P在高温下的热稳定性和成炭性与FR相比有较大的提高,它能促进PC热降解时成炭,使PC的热分解速率降低,当FR-P添加量为15%时,阻燃体系的LOI达31%,且通过UL94V-1级测试,其阻燃效果远远好于FR。     

耐热阻燃ABS/PBT合金的性能研究

以十溴二苯乙烷、三(三溴苯基)氰尿酸酯(溴代三嗪)和溴化环氧为阻燃剂、三氧化二锑为阻燃协效剂,对ABS/PBT合金进行阻燃改性,并在阻燃合金体系中引入聚碳酸酯(PC)协同阻燃及提高耐热性能。考察阻燃剂种类、PC含量和PBT含量对阻燃ABS/PBT合金的力学性能、耐热性能及阻燃性能的影响。结果表明,采用溴代三嗪作为阻燃剂制备的ABS/PBT合金综合性能较好;PC的引入可明显提高合金的力学性能和耐热性能,降低溴系阻燃剂及阻燃协效剂的添加量,但会导致合金流动性下降;随着PBT含量的提高,合金的拉伸性能、弯曲性能及流动性提高,冲击性能及热变形温度(HDT)稍有下降。     

磷酸酯与无机阻燃剂协同阻燃PC/ABS合金研究

研究了多聚芳基磷酸酯PX220分别与纳米蒙脱土和硼酸锌复配对聚碳酸酯/丙烯酸-丁二烯-苯乙烯共聚物(PC/ABS)合金的阻燃性能、热稳定性、力学性能及热变形温度的影响。结果表明:用2份纳米蒙脱土和3份硼酸锌分别与10份PX220复配制备阻燃PC/ABS,其氧指数分别达到28%和32%,燃烧性能达到UL94 V-0级。扫描电镜和热重分析表明,复配阻燃剂阻燃PC/ABS合金的炭层能有效隔绝热量的传递,阻止PC/ABS合金热降解,PC/ABS合金热稳定性明显提高。     

聚铝硅氧烷对聚碳酸酯阻燃性能的影响

采用水解缩合法制备了聚铝硅氧烷阻燃剂。应用热失重分析、锥形量热分析和极限氧指数研究了聚铝硅氧烷对聚碳酸酯（PC）热性能和阻燃性能的影响。结果表明,聚铝硅氧烷可降低PC的热降解速率,提高残炭量。添加质量分数为5 %的聚铝硅氧烷可使PC的极限氧指数从25.5 %提高到29.4 %,火灾性能指数提高了近2.5倍,并且显著降低了燃烧过程中产生的烟、热及CO、CO2等有害气体的释放量,有效提高了PC的阻燃性能。     

Flame retardancy,thermal, rheological,and mechanical properties of polycarbonate/polysilsesquioxane system

The polymethylphenylsilsesquioxane (PMPSQ) microspheres were used as an additive for the injection‐molding of polycarbonate (PC) in order to obtain a flame retardant polymer and to damage the other properties of PC as low as possible. The results showed that PMPSQ microspheres were a kind of effective flame retardant by the LOI test and the flame retardancy of PC increased with the increase of PMPSQ content. Thermogravimetric analysis suggested that the PMPSQ could induce crosslinking reactions and accelerate the thermal degradation of PC, sequentially promote the formation of the residue char during degradation. Differential scanning calorimetry measurement showed that the glass transition temperature of PC/PMPSQ system was decreased with the increase of PMPSQ content, which maybe caused by the enlarged free volume of PC‐rich phase. The rheological behaviors including dynamic and steady modes, combined with the analysis of scanning electron microscopy photographs, exhibited that the dispersion and compatibility of PMPSQ in the PC matrix decreased the viscosity of the systems and the addition of PMPSQ microspheres improved the processability of PC, but still there exist aggregation of PMPSQ microspheres in PC matrix, which gave a higher impact strength but a lower flexural modulus and elongation at break than pure PC. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

The effects of APP,APP/MMT nanocomposites on the thermal degradation of ABS resin

The thermal degradation of acrylonitrile‐butadiene‐styrene (ABS) added ammonia polyphosphate (APP) or APP/montmorillonite (MMT) nanocomposite was studied. The whole degradation progress of ABS could be regarded as the combination of the thermal degradation of polystyrene (PS) and polybutadiene (PB). The PB influences the formation of char while PS influences the maximum mass loss rate and its decomposition temperature. APP or APP/MMT nanocomposite could decrease the maximum mass loss rate and promotes the formation of char. A SiO₂ network was formed on the char surface of the ABS‐APP/MMT composite which could improve the strength of the char and flame retardancy of ABS. It was found that when APP/MMT mixture or APP/MMT nanocomposite are added to ABS, NH₃ (the gas product of APP) was buried in the residue and released until full degradation of ABS. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40704.     

PC/ABS/聚硼硅氧烷阻燃合金的性能

采用X射线能谱分析(EDX)研究了PC/ABS/聚硼硅氧烷阻燃合金的燃烧行为,同时考察了阻燃PC/ABS合金的力学性能和加工性能。结果表明,聚硼硅氧烷(PB)中的Si元素会随着燃烧过程的进行逐渐在合金表面进行富集,形成富含Si的绝缘炭层覆盖在基体表面,阻止合金继续燃烧,从而有效提高了PC/ABS合金的阻燃性能。聚硼硅氧烷使PC/ABS合金体系的力学性能有所下降,但拉伸强度下降较少,PB对PC/ABS合金的冲击强度影响较大。在阻燃PC/ABS合金体系中加入相容剂马来酸酐接枝ABS,可使合金体系的力学性能得到明显提高。适量的PB可以改善PC/ABS合金的加工性能。     

新型磷硅阻燃剂的合成及其对PC/ABS的阻燃研究

以三氯氧磷、季戊四醇和二乙氧基氨丙基硅甲烷为原料合成了一种磷硅阻燃剂PN,并通过红外光谱和核磁共振测定了其结构。将PN与聚碳酸酯/(丙烯腈/丁二烯/苯乙烯)共聚物(PC/ABS)体系共混后研究了PN对PC/ABS体系热降解性能、阻燃性能和残炭形貌的影响。结果表明,PN能改善PC/ABS体系的高温热稳定性和残炭量,在燃烧时形成内表面发泡、外表面致密连续的膨胀炭层;且能提高PC/ABS体系的阻燃性能,当PN的添加量从0增加到30份时,PC/ABS共混材料的极限氧指数由21%增加到29%;当PN添加量超过20份后,共混材料的阻燃等级能够达到UL94V-1级。     

熔融纺丝法制备聚醚砜纤维

将聚醚砜(PES)树脂进行熔融纺丝,制得PES纤维,对PES树脂的可纺性、PES纤维的拉伸条件、力学性能、热性能、阻燃性能进行了研究。结果表明：PES树脂在熔融温度380℃,卷绕速度300m/min的条件下,可纺性较好;PES纤维适合在较低温度和较低速度下拉伸,在30℃下低速拉伸,PES纤维可拉伸3倍,其强度可达2．30cN/dtex;PES纤维的热稳定较好,其初生纤维的起始分解温度为442．15℃;PES纤维的阻燃性能较好,极限氧指数为26．9%。     

氧化锌催化膨胀型阻燃剂对PP阻燃及力学性能的影响

研究了氧化锌催化膨胀型阻燃剂(APP/PER)对PP阻燃和力学性能的影响。研究表明,当APP/PER质量比为20/10,ZnO的质量分数为1．3%时,阻燃PP的LOI值达到最大；同时阻燃PP的拉伸强度和冲击强度比不含ZnO的PP有所提高。TG结果表明,ZnO的加入使阻燃PP燃烧时降解过程加快并生成更多的剩炭,形成稳定的保护层,从而提高了PP的阻燃效果。SEN的形貌观察表明,加入ZnO的试样燃烧炭膜孔径较小、孔膜较厚。     

Flame retardancy of polycarbonate–polydimethylsiloxane block copolymer/silica nanocomposites

This report describes the flame retardancy and the thermal degradation behavior of polycarbonate–polydimethylsiloxane (PC–PDMS) block copolymer/silica nanocomposites. PC–PDMS block copolymer with dimethylsiloxane (DMS) block size 40 units increased the dispersibility of nanosized amorphous silica. Addition of the slight nanosized silica caused the increment of flame retardancy of PC–PDMS block copolymer, and the PC–PDMS block copolymer with 1.0 wt % PDMS had the highest limiting oxygen index value when the nanosized silica was added 0.5 wt %. The maximum rate temperature of the PC–PDMS block copolymer increased with the addition of silica and the maximum loss rate was the lowest when silica content is 0.5 wt %. The monodisperse nanosized silica had an effect that enhances the flame retardant mechanism of PDMS for PC. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3862–3868, 2006     

1,4-二氯蒽醌水解制备1,4-二羟基蒽醌

以廉价的对二氯苯和邻苯二甲酸酐为原料制得1,4-二氯蒽醌,经硼酸催化水解得到1,4-二羟基蒽醌。系统地考察了反应温度、硫酸浓度、原料摩尔比和反应时间对氯转羟基反应的影响。确定了氯转羟基反应制备1,4-二羟基蒽醌的优化实验条件为：以95%浓硫酸为溶剂,在反应温度为220℃、硫酸∶1,4-二氯蒽醌∶硼酸（摩尔比）为37.5∶1.0∶1.4、反应时间为60min的条件下,以1,4-二氯蒽醌计的产物收率为71.0%。探讨和解释了硼酸催化作用下氯代蒽醌转换成羟基蒽醌可能的机理。     

Thermal degradation behaviors and flame retardancy of PC/ABS with novel silicon‐containing flame retardant

A novel flame retardant (DVN) containing silicon, phosphorus, and nitrogen has been synthesized from the reaction of 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO), vinylmethyldimethoxy silane (VMDMS) and N‐β‐(aminoethyl)‐γ‐aminopropyle methyl dimethoxy silane (NMDMS), then incorporated into polycarbonate/acrylonitrile butadiene styrene (PC/ABS) alloy. The flame retardancy of PC/ABS/DVN is evaluated by cone calorimeter and limited oxygen index (LOI) and the thermal degradation behavior is investigated by thermogravimetric analysis under nitrogen and air. The PC/ABS/DVN sample was thermally degraded at 400°C for different amounts of time and studied by Fourier transform infrared spectroscopy to better understand the mechanism of flame retardancy. The results show that the thermal stability and flame retardancy of PC/ABS are improved by incorporation of DVN. Scanning electric microscopy results show that the outer surface of the char layer of PC/ABS/DVN after the LOI test is smooth and the internal structure is like swollen cells, which benefits the flame retardancy of PC/ABS. Copyright © 2007 John Wiley & Sons, Ltd.