磷系阻燃共聚酯的结构与性能

采用磷系阻燃剂2-羧乙基苯基次磷酸（CEPPA）作为第3单体,通过聚合反应制备了含磷的阻燃共聚酯。采用核磁共振、DSC、元素分析和极限氧指数仪表征阻燃共聚酯的化学组成、序列分布、结晶性能、磷含量和极限氧指数。结果表明：大部分CEPPA单元以无规分布的形式共聚到聚酯分子链中,小部分CEPPA单元以短嵌段的形式共聚在聚酯分子链中,且随着阻燃剂含量增加,无规系数变小。由于分子链的规整性下降,与聚对苯二甲酸乙二酯（PET）相比,阻燃共聚酯的Tg和Tm下降,结晶度减小。随阻燃剂含量的增加,极限氧指数值增加,当阻燃共聚酯中的磷含量达到9．08mg／g时,极限氧指数值达到33％以上。     

Preparation of Boron-coated Expandable Graphite and Its Application in Flame Retardant Rigid Polyurethane Foam

A novel boron-coated expandable graphite(BEG) material was prepared by first wrapping polyvinyl alcohol(PVA) onto expandable graphite(EG) and then condensing with boric acid. The obtained BEG was characterized by scanning electron microscopy(SEM), Fourier transform infrared(FTIR) spectroscopy, X-ray photoelectron spectroscopy(XPS), and thermogravimetric analysis(TGA). The fire performance and mechanical properties of the rigid polyurethane foam(RPUF) filled with BEG were investigated by limiting oxygen index(LOI), horizontal and vertical burning, cone calorimetry(CONE), and electronic tensile tests. BEG shows an improved compactness of the char layers upon thermal expansion, which is effective for the flame retardancy of RPUF. With a loading of 10%, RPUF/BEG exhibited a higher LOI, >10% reduction in heat release rate and carbon monoxide release, as well as a decrease in smoke release during the beginning of combustion compared to RPUF/EG. Moreover, the compressive strength and modulus of RPUF/BEG were increased. The improved flame retardancy of BEG on RPUF can be attributed to the suppression of the "popcorn effect" of EG by PVA-boric acid, and the improved mechanical property can be attributed to the presence of PVA.     

Effect of Blowing Agent Type in Rigid Polyurethane Foam

Rigid polyurethane foams have been fabricated from polymeric MDI and polypropylene glycols (PPG) synthesized with two different initiator compositions using two different types of blowing agents, viz., the conventional HCFC 141b and environmently friendly HFC 365 mfc. It was found that the two blowing agents gave identically the same cream time, gel time, and tack‐free time. The HFC 365 mfc gave foams with smaller cell size, greater core density and compression strength, whereas HCFC 141b gave better dimensional stability and thermal insulation. For the same type of blowing agent, the initiator containing more toluene diamine gave greater core density, compression strength and thermal insulation     

改性可膨胀石墨的制备及在硬质聚氨酯泡沫中的阻燃性能

采用表面接枝硅烷偶联剂法将硼酸负载在可膨胀石墨(EG)表面制得了改性EG(MEG), 并考察了MEG在硬质聚氨酯泡沫(RPUF)中的阻燃性能. 利用扫描电子显微镜、 X射线光电子能谱、 傅里叶变换红外光谱、 膨胀试验及热失重分析对MEG进行了形貌、 元素组成及结构性能表征, 通过热失重分析、 极限氧指数(LOI)及锥形量热仪考察了RPUF/MEG的热稳定性及燃烧性能. 结果表明, 硼硅化合物作为硅硼陶瓷前驱体已负载在EG表面; MEG及RPUF/MEG体系膨胀炭层更为致密, 800 ℃时的残余量分别较EG和RPUF/EG提高了8.7%和3.7%; RPUF/MEG体系的LOI较RPUF/EG有所提高, 热释放速率峰值降低了10%, 产烟速率及CO生成速率均显著降低. RPUF/MEG阻燃性能的提高与MEG负载的硅硼陶瓷前驱体促进了阻燃RPUF各组分间的相互作用及增强了炭层的阻隔性有关.     

新型单组分磷-氮膨胀型阻燃剂的合成及其阻燃性能

以氯化螺环磷酸酯(1)和对甲苯胺(2)为原料,经亲核取代反应合成了三源一体的新型单分子磷-氮膨胀型阻燃剂——季戊四醇螺环磷酰对甲苯胺(3),其结构经1H NMR和IR表征。考察了溶剂、原料配比、反应温度、反应时间和缚酸剂对3产率的影响。合成3的最佳反应条件为:乙腈为溶剂,三乙胺为缚酸剂,1 10mmol,n(1)∶n(2)=1∶3,于80℃反应4 h,产率79.3%。阻燃性能研究结果表明,3的初始分解温度为220℃,500℃成炭率达43.3%。     

Effect of Phosphorus-Nitrogen Intumescent Flame Retardant on Structure and Properties of Poly(propylene)

Summary : Phosphorus-nitrogen intumescent product (R₂₀₀₀) was filled into polypropylene (PP) as a flame retardant. The neat PP and flame-retarded PP blends were studied for their structural and mechanical properties after verification of the flame retardancy character of blends. In this paper, the influence of incorporation of different amount (5%, 10%, 15%, 20%, and 25%) of R₂₀₀₀ was studied. The flame retardancy is evaluated by limiting oxygen index (LOI) value, which is enhanced from 17.5 for pure PP to 22.7 for the blend comprising 15% intumescent product, phosphorus-nitrogen based (R₂₀₀₀). The thermal degradation behaviour of the PP/R₂₀₀₀ blends was investigated using thermogravimetric analysis (TGA) under nitrogen (N₂) and oxygen (O₂) atmospheres. The influence of the R₂₀₀₀ on the PP crystallization was examined by X-ray diffraction (XRD) and differential scanning calorimetry (DSC). Further, the mechanical properties of the materials were studied by dynamic mechanical analysis (DMA). The incorporation of the flame retardant had no effect on the crystallization of the neat polymer and the mechanical properties of the materials remained unaffected.     

高岭土对不饱和聚酯树脂的热稳定性、阻燃及力学性能的影响

不饱和聚酯树脂;高岭土;纳米复合材料;原位聚合;阻燃;成炭     

新型磷杂菲基反应型阻燃剂的合成及其在聚氨酯阻燃中的应用

以9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物和1,4-丁二醇二缩水甘油醚为原料,合成了一种新型的反应型阻燃剂1-（2-羟基-3-磷杂菲）丙氧基-4-环氧丙氧基丁烷(1),其结构和性能经¹H NMR, ³¹P NMR, FT-IR和TG表征。以1为封端剂,聚氨酯（PU）为基材,制备了1/PU阻燃复合材料（2）,研究了1对2阻燃性能和力学性能的影响,初步探讨了1的阻燃机理。结果表明:1具有气相和凝聚相阻燃作用,2燃烧后可形成致密光滑炭层,使点燃时间延长,改善了燃烧熔滴现象。1含量为1%时,2¹的LOI为27%, UL-94燃烧等级为V-0级。     

热塑性聚氨酯微孔发泡材料的表观密度与其力学性能的关系

用高压CO2流体通过升温发泡法制备了一系列不同表观密度的热塑性聚氨酯(TPU)微孔发泡材料,探究了TPU发泡材料的表观密度与其力学性能的关系.微孔发泡材料的泡孔结构和表皮结构由扫描电子显微镜表征;不同表观密度材料的力学性能利用万能材料试验机和旋转流变仪表征.研究发现:TPU微孔发泡材料的表观密度主要是由材料皮层厚度占比和泡孔层密度决定的,皮层厚度占比越小和泡孔面积占有率越高,泡沫的表观密度越小;微孔发泡材料在线性应变区的压缩模量E与材料表观密度ρ的关系为:E∝ρ1.7,符合泡沫材料压缩模量与表观密度呈指数关系的基本结论;循环压缩实验中,随微孔发泡材料表观密度减小,损耗百分比增大,残余应变减小;流变实验中,微孔发泡材料的模量随表观密度变化没有明显的变化,阻尼因子tanδ随泡沫表观密度变化不呈单一的规律性.同时,阐明了微孔发泡材料的压缩模量E和损耗百分比随表观密度变化的机理.     

新型磷-氮有机金属阻燃剂的合成及其热稳定性

以γ-氨丙基三乙氧基硅烷(1)和二苯基氯化膦(2)为原料,经取代反应制得N-(二苯基膦基)-1,1-二苯基-N-［3-(三乙氧基甲硅烷)丙基］膦氮配体(3); 3与六水合氯化镍(4)反应合成了一种新型的磷-氮有机金属阻燃剂(5),其结构经¹H NMR, ³¹P NMR和FT-IR表征。研究了物料比［r=n(2) : n(1)］、溶剂、反应时间和反应温度对3收率的影响。结果表明：在最佳反应条件［二氯甲烷为溶剂,1 19 mmol, r=2.3,于25 ℃反应14 h］下,3收率89.5%。 TGA测试结果表明：5的初始分解温度为252 ℃, 700 ℃残炭为31.9%。     

磷杂菲改性腰果酚多元醇的合成及阻燃聚氨酯硬泡性能

采用生物质原料腰果酚和9,10-二氢-9-氧杂-10-膦杂菲-10-氧化物(DOPO)为原料, 合成了一种磷杂菲改性腰果酚多元醇(P-Cardanol-Polyol), 并利用核磁共振氢谱和磷谱对其结构进行了表征. 利用P-Cardanol-Polyol对聚氨酯硬泡(RPUF)进行阻燃改性, 得到一系列阻燃聚氨酯硬泡. 考察了P-Cardanol-Polyol的用量对阻燃聚氨酯硬泡的形貌、 密度、 热导率、 压缩性能、 热稳定性以及阻燃性能的影响. 研究结果表明, P-Cardanol-Polyol对聚氨酯硬泡的密度影响可以忽略不计; 随着P-Cardanol-Polyol的加入, 阻燃聚氨酯硬泡的平均孔径逐渐减小, 热导率也逐渐降低. 未改性聚氨酯硬泡的最大热释放速率和总放热量分别为390 kW/m²和31.9 MJ/m², 阻燃聚氨酯硬泡则降低至340 kW/m²和24.6 MJ/m². 此外, 阻燃聚氨酯硬泡的压缩强度比未改性聚氨酯硬泡提升了约13%. 炭层分析结果表明, P-Cardanol-Polyol能够促进聚氨酯硬泡形成连续致密且具有良好抗热氧化性能的炭层, 有利于减少燃烧过程中可燃性气体的逸出, 从而提升阻燃性能.     

2,4-二氯苯甲酸改性饱和聚酯的合成及其聚氨酯阻燃涂料

用2,4-二氯苯甲酸改性三羟甲基丙烷制得含氯的多元醇中间体（NHDB）,用改性的中间体合成含氯的聚酯。用红外、核磁表征了中间体和聚醇的结构,TGA分析表明,含氯量增高,聚酯热稳性下降。将聚酯同异氰酸酯预聚体常温固化,各种性能良好。阻燃测试表明：含30%的2,4-二氯苯甲酸的聚酯具有自熄功能。提出了阻燃机理。     

Synthesis of Novel Arginine-Based Flame Retardant and Its Application in Lyocell Fabric

Lyocell fabrics are widely applied in textiles, however, its high flammability increases the risk of fire. Therefore, to resolve the issue, a novel biomass-based flame retardant with phosphorus and nitrogen elements was designed and synthesized by the reaction of arginine with phosphoric acid and urea. It was then grafted onto the lyocell fabric by a dip-dry-cure technique to prepare durable flame-retardant lyocell fabric (FR-lyocell). X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FTIR) analysis demonstrated that the flame retardant was successfully introduced into the lyocell sample. Thermogravimetric (TG) and Raman analyses confirmed that the modified lyocell fabric featured excellent thermal stability and significantly increased char residue. Vertical combustion results indicated that FR-lyocell before and after washing formed a complete and dense char layer. Thermogravimetric Fourier-transform infrared (TG-FTIR) analysis suggested that incombustible substances (such as H₂O and CO₂) were produced and played a significant fire retarding role in the gas phase. The cone calorimeter test corroborated that the peak of heat release rate (PHRR) and total heat release (THR) declined by 89.4% and 56.4%, respectively. These results indicated that the flame retardancy of the lyocell fabric was observably ameliorated.     

Effect of blowing agent content on the structure and flame-retardant properties of rigid polyurethane foam/expanded graphite composites

Driven by global environmental issues, the development of green building materials has become an immediate focus. In this work, n-pentane was used as an environmentally friendly blowing agent to prepare flame-retardant rigid polyurethane foam (RPUF) with the addition of expandable graphite (EG) successfully, and the effect of n-pentane content on flame retardancy and compressive properties of RPUF/EG composites was investigated through limit oxygen index (LOI), vertical burning test (UL-94), scanning electron microscope (SEM), thermogravimetric analysis (TGA), and compressive properties test. SEM results show that the content of EG and n-pentane causes a change in the cell structure of RPUF. The change of the n-pentane content has also an obvious effect on the thermal stability, flame retardancy, and specific compressive strength of RPUF/EG composites. In addition, the cell structure of RPUF matrix has an obvious influence on the distribution of EG in the composites, which indirectly affects the flame-retardant efficiency of EG. This research explores the conditions for the application of environmentally friendly RPUF and expands its application prospects.     

新型含磷阻燃剂DOPO-PPO的合成及其阻燃性能

以苯基磷酰二氯,对羟基苯甲醛及9,10-二氢-9-氧杂-10-磷杂菲(DOPO)为原料,合成了一种新型含磷阻燃剂——二[4-(次甲基-羟基-磷杂菲)苯氧基]苯基氧化磷(DOPO-PPO),其结构经1H NMR和IR表征。通过TGA和DTG研究了DOPO-PPO的热稳定性,热降解行为及成炭性能。结果表明:DOPO-PPO的起始热分解温度为210℃,在700℃时残炭为30.4%。以环氧树脂为基材,DOPO-PPO为阻燃剂,二氨基二苯硫砜为固化剂,制备了阻燃环氧树脂(3)。通过极限氧指数(LOI)和垂直燃烧(UL-94)测试了3的阻燃性能。结果表明:当DOPOPPO的添加量为12.0%(质量百分数,即312)时,阻燃级别为V-0级,LOI为34.0%。     

Synthesis and Characterization of Borax-Polyimide for Flame Retardant Applications

Polyamide-borax composites were prepared from solution of polyimide and the borax using N-methyl-2-pyrrolidone as a solvent. The Polyimide-borax composites films (PI-BX) characterized by FTIR, SEM and x-ray. The borax content significantly influences thermal behavior of the polymeric films, such as glass transition and decomposition temperatures of polyimide-borax composites. The glass transition temperatures of the composites were higher than that of the original polyimide. The flammability properties of them were demonstrated by cone calorimeter and indicate that the borax composites have significantly decreased in heat release rate, and mass loss rate. The PI-BX composites appears very good the flame retardant properties.     

Studying the Suitability of Nineteen Lignins as Partial Polyol Replacement in Rigid Polyurethane/Polyisocyanurate Foam

In this study, nineteen unmodified lignins from various sources (hardwood, softwood, wheat straw, and corn stover) and isolation processes (kraft, soda, organosolv, sulfite, and enzymatic hydrolysis) were used to replace 30 wt.% of petroleum-based polyol in rigid polyurethane/polyisocyanurate (PUR/PIR) foam formulations. Lignin samples were characterized by measuring their ash content, hydroxyl content (Phosphorus Nuclear Magnetic Resonance Spectroscopy), impurities (Inductively Coupled Plasma), and pH. After foam formulation, properties of lignin-based foams were evaluated and compared with a control foam (with no lignin) via cell morphology, closed-cell content, compression strength, apparent density, thermal conductivity, and color analysis. Lignin-based foams passed all measured standard specifications required by ASTM International C1029-15 for type 1 rigid insulation foams, except for three foams. These three foams had poor compressive strengths, significantly larger cell sizes, darker color, lower closed-cell contents, and slower foaming times. The foam made with corn stover enzymatic hydrolysis lignin showed no significant difference from the control foam in terms of compressive strength and outperformed all other lignin-based foams due to its higher aliphatic and p-hydroxyphenyl hydroxyl contents. Lignin-based foams that passed all required performance testing were made with lignins having higher pH, potassium, sodium, calcium, magnesium, and aliphatic/p-hydroxyphenyl hydroxyl group contents than those that failed.     

Thermal Aging Effect on Mechanical Properties of Polyurethane

This study concerns the effect of thermal aging on mechanical properties of polyurethane. Polyurethane samples were exposed at 85° and 120°C under inert atmosphere. Mechanical tests were carried out on these samples the aging period. Tensile tests were performed to see the effect of aging on elastic modulus (E), stress (σ_r), and strain (?_r) at break. It was shown that there are two distinct periods. Due to aging, E and σ_r increase in the first period, then they decrease in the second period. ?_r decreases first and then increases. Fatigue tests were performed on unaged and aged samples. It was shown that the fatigue behavior of polyurethane (PU) is improved the same way during the first stage of aging. In the second step, the number of cycles to failure increases due to aging. The results show that aging has an important effect on mechanical properties of PU. The strain at break decreases during the first step of aging due to post-cross-linking and then increases due to chain scission in the network. Based on these results, the effect of cross-linking and chain scission on the mechanical properties of PU was discussed.     

Chemical Recycling and Liquefaction of Rigid Polyurethane Foam Wastes through Microwave Assisted Glycolysis Process

Glycolysis of polyurethane rigid foams (PUFs) was performed utilizing microwave irradiation at atmospheric pressure. The effects of various metal hydroxide and acetate catalysts as well as different microwave powers were investigated. All reactions were monitored by FTIR spectroscopy. The recovered liquid product containing OH functional groups was applied as a portion of the polyol in formulation of a new polyurethane rigid foam product. The reactivity factors and densities were compared with the foam produced from totally virgin polyol.     

MgAlZnFe-CO3 LDHs对PBS膨胀阻燃体系性能的影响

采用恒定pH值共沉淀法在自制反应器中合成了不同原料配比的碳酸根型镁铝锌铁层状双羟基金属氧化物（MgAlZnFe-CO₃ LDHs）,并通过熔融共混MgAlZnFe-CO₃ LDHs、聚磷酸铵（APP）、三聚氰胺（MA）和全降解材料聚丁二酸丁二醇酯（PBS）制备出PBS膨胀阻燃材料. 采用傅里叶红外光谱（FTIR）、热失重（TG）、X射线衍射（XRD）、扫描电子显微镜（SEM）及元素分析（ICP）对MgAlZnFe-CO₃ LDHs进行了表征,并对PBS膨胀体系进行了力学性能和阻燃性能等测试. 结果表明,当Mg²⁺,Zn²⁺,Al³⁺和Fe³⁺的摩尔比为9：3：3：1时,合成的MgAlZnFe-CO₃ LDHs热稳定性最好,晶态结构规整,呈形貌规则的六边形片状;当MgAlZnFe-CO₃ LDHs的添加质量分数为1%时（阻燃剂的总添加质量分数为20%）时,PBS膨胀阻燃体系的极限氧指数（LOI）达到35%,垂直燃烧测试达到UL-94 V-0级别,力学性能得到较大改善. 实验结果表明,低添加量的MgAlZnFe-CO₃ LDHs与膨胀阻燃剂（IFR）协效阻燃PBS,一方面能够改善膨胀阻燃剂恶化PBS力学性能的现象,另一方面协同效应能够明显提高PBS的阻燃性能.