New aspects in cationization of lignocellulose materials. VIII. Modification of immitted spruce wood with quarternary ammonium groups

Immitted spruce wood meal (ISWM) was modified with 3-chlor-2-hydroxypropyltrimethyl-ammoniuchloride (CHMAC) or 1,3-bis(3-chlor-2-hydroxypropyl)imidazoliumhydrogensulphate (BCHIHS) in alkaline medium. The obtained material was gradually extracted with water and 5% NaOH. The yields of water-soluble hemicelluloses modified with quarternary ammonium groups were lower in comparison to healthy spruce material obtained under the same conditions but even more material could be obtained from ISWM-holocellulose. The quantity of alkali-soluble polysaccharides from ISWM was the same as obtained from undamaged spruce. The residues after alkali extractions are suitable ion exchangers with low solubility in dilute alkali solutions. The yields of extracts from material modified with BCHIHS were lower than yields of extracts from material modified with CHMAC because ISWM was crosslinked when alkylated with bifunctional chemicals.     

甲基膦酸二甲酯/木质素磺酸钠聚氨酯泡沫的制备及其阻燃性能

利用木质素磺酸钠(SLS)替代部分聚醚多元醇,同时将甲基膦酸二甲酯(DMMP)作为添加型阻燃剂,采用"一步发泡法"制备出甲基膦酸二甲酯/木质素磺酸钠聚氨酯泡沫材料(DMMP/SLS/PUF),通过极限氧指数(LOI)测试对其阻燃性能进行分析,探究了 SLS替代率及DMMP添加量对材料阻燃性能的影响.并利用锥形量热(CO...     

聚氯乙烯(PVC)电缆料阻燃性能的研究

研究了纳米三氧化二锑、普通微米级三氧化二锑及纳米三氧化二锑/硼酸锌复配阻燃剂对PVC电缆料的阻燃性能及力学性能的影响。研究结果表明:纳米三氧化二锑对PVC氧指数的贡献大于微米级三氧化二锑,当氧指数为35%时,纳米三氧化二锑的添加量比微米级三氧化二锑减少20%;将纳米三氧化二锑与硼酸锌复合后材料的氧指数降低,但生烟量与成本降低;随着复配阻燃剂中硼酸锌比例的增加,PVC电缆料的拉伸强度与断裂伸长率的降低均不明显。     

MH/ATH/纳米硅树脂阻燃电缆料的制备与研究

以LDPE、EVA为基体,MH、ATH、纳米硅树脂粉为阻燃剂,通过挤出造粒、注塑成型制得高性能无卤少烟阻燃电缆料。通过极限氧指数、万能电子拉力机、热重分析、傅里叶红外等研究手段研究电缆料的阻燃性能、耐热性能及其力学耐油耐老化性能。结果表明:P2体系有较好的阻燃性、耐热性、耐油、耐老化以及良好的力学性能,适合用作对阻燃要求较高的阻燃电缆料。     

Preparation and characterization of the halogen-free,smoke suppression,organic–inorganic hybrid flame-retardant expandable polystyrene materials

Expandable polystyrene (EPS) is a plastic widely used in the field of construction, but it is flammable. This work provided a novel strategy for flame-retardant modification of EPS. A kind of polyester polyol (JZP) with the high content of phosphorus and nitrogen was synthesized. Then, intrinsic flame-retardant polyurethane (PFWPU) with the high content of phosphorus and nitrogen was synthesized by JZP acted as soft segment chain extender. Finally, a high-efficiency flame-retardant expandable polystyrene thermal insulation material (AF-EPS) was prepared by the organic–inorganic hybrid flame-retardant synergistic action of PFWPU and ammonium polyphosphate. The effects of different contents of inorganic flame retardants on flame retardancy of materials were studied by limiting oxygen index (LOI), cone calorimetry, thermogravimetric analysis/infrared spectrometry , scanning electron microscopy, and so on. The test results showed that the carbon residue rate of the modified material increased from 0 to 28.5%, the LOI increased from 17 to 35.8%, and the vertical combustion test reached the highest grade V-0. In addition, the total smoke production of AF-EPS samples decreased from 2.33 m² to 0.57 m², the time to ignition was increased to 41 s, and the peak heat release rate and the total heat release were decreased by 90.2 and 62.7%, respectively.     

含磷腈衍生物阻燃粘胶纤维的结构与性能

以环状磷腈衍生物为阻燃剂,采用添加改性方法制备阻燃粘胶纤维,采用极限氧指数法、45°倾斜燃烧法、X射线衍射法、扫描电镜等研究了阻燃剂对粘胶纤维燃烧性能和物理机械性能的影响。结果表明, 所制备的阻燃粘胶纤维结晶度和回潮率都随阻燃剂含量增加而降低,回潮率最大下降2．33％,初始模量和断裂强度则呈先增加后降低的趋势。阻燃剂质量分数为8．2％-10．0％的粘胶纤维的机械力学性能较好, 极限氧指数大于28,45°倾斜燃烧法接火次数超过3次。     

Flame retardancy of unsaturated polyester composites with modified ammonium polyphosphate,montmorillonite, and zinc borate

Ammonium polyphosphate (APP) was modified using a new method, where the resulting modified APP (MAPP) was obtained by mixing APP with unsaturated polyester resin (UPR). MAPP was more effective in improving the flame retardancy of UPR than APP which was due to the improved dispersion of MAPP in UPR composite. Then, the UPR composites were prepared based on dimethyl methylphosphonate, MAPP, montmorillonite, and zinc borate. Finally, the flame-retardant and mechanical properties of the UPR composites were analyzed using the limited oxygen index (LOI), thermogravimetric analysis, UL-94 vertical burning test, scanning electron microscopy, cone calorimetry, mechanical tests, and viscosity measurements. The LOI and UL-94 tests showed that the flame-retardant properties clearly improved with the addition of fillers in the UPR composites compared to pristine UPR. The synergistic effect of Si- and P-containing flame retardants in this composite resulted in the LOI value increasing from 18.9 to 31.3% and achieved the UL-94 V-0 rating. Moreover, the heat release rate was lower than the pristine UPR. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47180.     

New aspects in cationization of lignocellulose materials. VI. Modification of steam-exploded aspen wood chips with quarternary ammonium groups

Holocellulose prepared from steam-exploded aspen wood was gradually fractionated with 2.5% NH₄OH, 4.5% NaOH, and 17.5% NaOH, respectively. Some residual polysaccharides were extracted from the material in this way, but their yield was only about 5%. Trimethylammonium-2-hydroxypropyl (TMAHP)-derivatives, exploded aspen wood (EXAW), were prepared by the reaction with 3-chlor-2-hydroxypropyl trimethylammoniumchloride (CHMAC) in alkaline medium. The quantity of water and alkali extracted TMAHP–polysaccharides (yield 2.6%) was lower than the yields from modified healthy beech and aspen, as well as rotten aspen. On the other hand, we can obtain more modified cellulose-rich and lignin-rich material than from previously mentioned species. The steam-explosion process is suitable for increasing the accessibility of cellulose component in lignocellulose material for chemical modification.     

高抗冲聚苯乙烯的阻燃及增韧研究

采用十溴二苯醚(DBDPO)和三氧化二锑(Sb_2O_3)为阻燃复合体系对高抗冲聚苯乙烯(HIPS)进行阻燃改性,研究了阻燃复合体系对HIPS共混材料阻燃性能和力学性能的影响.结果发现:当DBDPO与Sb_2O_3的质量比为3:1时,HIPS共混材料的氧指数达到28%,阻燃效果较好,同时力学性能损失较小;加入无机阻燃剂可以抑制HIPS共混材料燃烧,明显降低发烟量;并比较了增韧剂种类和用量对HIPS共混材料阻燃性能和力学性能的影响.     

六苯氧基环三磷腈阻燃PC/ABS合金及其高性能化研究

采用熔融挤出法制备了阻燃聚碳酸酯/丙烯腈丁二烯苯乙烯共聚物（PC/ABS）合金材料。利用热失重分析仪、氧指数测试仪、垂直燃烧仪、锥形量热仪、电子万能试验机和冲击试验机研究了相容剂马来酸酐接枝聚乙烯共聚物（PE-g-MAH）以及阻燃剂六苯氧基环三磷腈（HPCTP）的加入对PC/ABS合金材料的热稳定性、阻燃性能和力学性能的影响,并采用扫描电子显微镜对材料的残炭形貌进行分析。结果表明,当PC/ABS的质量比为7/3,以PE-g-MAH为相容剂,且HPCTP添加量为15 %时,阻燃PC/ABS合金材料的综合性能最好,其极限氧指数为26.4 %,热释放速率峰值及热释放总量达到最小值,且能够达到UL 94 V-0级,拉伸强度和缺口冲击强度分别为55 MPa和32.9 kJ/m2。     

Polylactic acid flame-retardant composite preparation and investigation of flame-retardant characteristics

Polylactic acid (PLA) is a new type of biodegradable material with good mechanical properties, and is widely used in many fields. However, as PLA is highly flammable, it is necessary to conduct flame-retardant modification research on PLA. Phosphorus heterophilic flame retardants are low smoke, non-toxic and have high flame-retardant efficiency, and also have broad application prospects. In this study, a phosphazene flame retardant, 9,10-dihydro-9-oxa-10-phosphazene-10-yl-hydroxy-phenol (abbreviated as DOPO-PHBA), was synthesized. The PLA/ECE/DOPO-PHBA flame-retardant composites were prepared by adding DOPO-PHBA and epoxy chain extender (ECE) into PLA. Thermal, mechanical, and flame-retardant properties, as well as microscopic morphology of the PLA flame-retardant composites were characterized and analyzed, and the flame-retardant mechanism was discussed. Results show that when the flame-retardant DOPO-PHBA is added at 5 wt%, the PLA composites can reach the V-0 level of combustion, and the corresponding LOI value is 30.0% at this time, and the LOI value increases from 22.5% to 33.6% with the increase of the flame-retardant content. In addition, PLA composites still have good mechanical properties, and the cone heat, carbon residue and the thermal decomposition process shows that the flame-retardant causes a two-phase flame-retardant mechanism on PLA with the gas and condensed phases acting in synergy. High flame retardancy is mainly attributed to free radical quenching, gas dilution, and the thermal barrier caused by the carbon layer. This work provides a simple and scalable method for the preparation of high-performance flame-retardant PLA materials.     

阻燃型丁腈橡胶/氯化聚丙烯橡塑复合材料的制备与性能研究

通过在丁腈橡胶(NBR)/氯化聚丙烯(CPP)橡塑复合材料中添加协同阻燃剂三氧化二锑,制备了阻燃型NBR/CPP橡塑复合材料,考察了三氧化二锑用量对NBR/CPP橡塑复合材料硫化特性、力学性能和燃烧性能的影响。实验结果表明:三氧化二锑的加入没有降低NBR/CPP橡塑复合材料的加工性能;当三氧化二锑用量为10.0份时,NBR/CPP橡塑复合材料的拉伸强度、300%定伸应力和邵氏硬度分别增加了15.7%、112%和10.9%;复合材料的氧指数(LOI)随三氧化二锑用量的增加逐渐增大,当三氧化二锑用量为2.5份时,复合材料氧指数为27.4%,达到自熄级阻燃效果。     

环氧树脂和ZnO对微胶囊红磷阻燃HIPS体系影响

研究了环氧树脂和ZnO对微胶囊红磷阻燃高抗冲聚苯乙烯(HIPS)性能的影响。结果表明,当微胶囊红磷用量为8 phr时,随着环氧树脂用量的增加,HIPS的阻燃性能提高;当环氧树脂用量大于20 phr时,阻燃HIPS 的垂直燃烧达到UL 94 V-0级,极限氧指数(LOI)为28．8％。在微胶囊红磷-环氧树脂复合阻燃HIPS体系中添加 ZnO具有阻燃协同作用,仅需加入2 phr。的ZnO就能使微胶囊红磷／环氧树脂质量比为8:15的阻燃HIPS体系垂直燃烧达到UL 94 V-O级,LOI也可达到29．2％。     

阻燃羊毛纤维的热性能研究

用氟锆酸钾、有机二酸处理羊毛线、用热分析、剩碳率及氧指数等分析方法对其阻燃性进行了研究,并用Kissinger方程计算热降解反应活化能。实验证明：经过阻燃处理的羊毛毛线比未经阻燃处理的羊毛毛线的剩碳率、氧指数均有所提高,热降解反应活化能和热分解温度降低。     

改性三氧化二锑协效二乙基次磷酸铝阻燃PA6研究

采用硅烷偶联剂（KH560）对三氧化二锑（Sb₂O₃）进行表面改性处理,并将其协效二乙基次磷酸铝（ADP）应用于聚酰胺6（PA6）阻燃研究。采用傅里叶变换红外光谱和热失重分析对改性Sb₂O₃进行表征,运用垂直燃烧、氧指数、锥形量热仪、热分析以及扫描电子显微镜和拉曼光谱等对阻燃PA6进行了阻燃性能及机理分析。结果表明,改性 Sb₂O₃与Sb₂O₃相比,与ADP具有更好的协同阻燃效应,其作用机制主要是在气相发挥阻燃作用;当ADP含量为8 %,改性Sb₂O₃含量为2 %时,阻燃PA6复合材料的UL 94等级达到V?0级,极限氧指数达到33.8 %。     

尼龙6/纳米三氧化二锑性能的研究

采用等离子体法生产的纳米三氧化二锑制备阻燃尼龙6(PA6),并通过氧指数(LOI)、锥形量热及TEM等检测,研究了纳米三氧化二锑对PA6阻燃性能和力学性能的影响。结果表明,当纳米三氧化二锑质量分数为6%时,LOI可达30%;热释放速率峰值减小了60 kW/m2,且达到峰值的时间较纯PA6延迟了约2 min;硅烷偶联剂KH-550改性的纳米三氧化二锑在PA6中的弥散度比未改性的高。与未改性纳米三氧化二锑相比,经过表面改性后,材料的拉伸强度提高60.7%、缺口冲击强度提高14.8%、弯曲强度提高36.8%、弯曲模量提高39.6%。     

六苯氧基环三磷腈的合成及其在丙烯酸树脂中的阻燃应用

以六氯环三磷腈（HCCP）、苯酚、氢化钠为原料,碳酸钾为催化剂,丙酮为溶剂,在氮气保护下合成了六苯氧基环三磷腈（HPCP）。采用红外光谱、核磁氢谱、碳谱、磷谱、差示扫描量热分析、热重分析技术对产物进行了表征。将HPCP作为阻燃剂添加到丙烯酸树脂中,测试了HPCP不同添加量的丙烯酸树脂的阻燃性和热稳定性。结果表明,当HPCP的添加量为20 wt %时,丙烯酸树脂的垂直燃烧可达UL-94 V-0级,极限氧指数从17.5 %增加到32.2 %,空气中700 ℃时残留质量提高至18.95 %,平均热释放速率（Mean HRR）和总热释放量（THR）分别降低至43 kW/m2和37 MJ/m2。     

Oxygen index: Correlations to other fire tests

An investigation has been carried out of the limiting oxygen index (LOI) test. A review of the literature shows that, although there is abundant information on the test, it is not clear that its results correlate well with those of any other test, or indeed with those of real fires. Theoretical considerations indicate that the test could be improved by using it with bottom ignition rather than with the standard top ignition. A number of materials were tested in the cone calorimeter and in the LOI, and various correlations were attempted. In general, correlations between some of the cone calorimeter properties measured and the inverse of the LOI made sense. These correlations were not, however, sufficiently sensitive, even when investigating small effects on a single base polymer system, to justify using the LOI as a proxy for the cone in any way. The LOI is likely to continue to be used extensively. This work suggests that quality control and, possibly, mechanistic or other flame-retardant additive studies, are its only applications where the results can be justified.     

橡胶表面用无卤协同阻燃聚氨酯脲的性能研究

以HDI三聚体／IPDI预聚体为固化剂,聚天门冬氨酸酯为扩链剂,烷羟基硅油／氮磷羟基阻燃聚醚POP（Si-N／P）与聚磷酸铵（APP）／季戊四醇（PER）为协同阻燃剂,设计了橡胶表面用无卤协同阻燃聚氨酯脲弹性体。讨论了协同阻燃剂用量对体系阻燃与机械性能的影响。结果表明,无卤协同阻燃聚氨酯脲弹性体具有较好的阻燃性能和机械性能,当Si—N／P质量分数为20％,APP／PER质量分数为30％时,其极限氧指数（LOI）从18提高到33,拉伸强度5．2MPa,断裂伸长率235％．邵A硬度57,可实现与橡胶基材匹配的协同运动。     

Influence of modified ammonium polyphosphate on the fire behavior and mechanical properties of polyformaldehyde

In this work, three kinds of APP, coated with melamine (MF-APP), silane (GW-APP), epoxy (MC-APP) were employed to compound with novolac resin (Novolac) and melamine (ME), aimed to study the effect of the modified APP on the flame-retardant performance, mechanical properties, and thermal stability of polyformaldehyde (POM). The results showed that composites with modified APP exhibited better flame retardant and mechanical performance than that with unmodified APP. In contrast, GW-APP had the best synergistic effect with Novolac and ME, and POM/GW-APP composites reached UL-94 V-0 rating and its limit oxygen index (LOI) value was up to 34.0%. The morphology of the carbon layer showed that the silane coating material can promote the charring process in condensed phase better than epoxy and melamine coating materials in flame retardant POM system, leading to the formation of integrated char layers with more quantity and higher quality, which effectively delayed the mass and heat transfer during combustion.