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51.
Youxian Hu Zhenlin Jiang Min Zhu Shiqiang Song Liang Jin Hong Ji Chaosheng Wang Jianhua Wang 《乙烯基与添加剂工艺杂志》2021,27(2):432-444
Polyester is widely used in household products because of its good mechanical properties and wears resistance, but polyester is easy to ignite and inclined to produce droplet, so its application range is limited. The cross-linkable magnesium hydroxide nanoparticles were incorporated into flame-retardant polyester, which enables the phosphorus-containing copolyester with thermal cross-linking and anti-meltdrop properties. The nanoparticles were achieved by in situ polymerization and acted as a nucleating agent for improving the crystalline properties of the copolyester. Furthermore, the nanoparticles also enhanced anti-meltdrop properties and reduced the heat and gas release during the combustion process of the copolyester. The maximum heat release rate and total smoke release reduced by 39.8% and 74.4% compared with pure polyester. Specifically, the combustion products of the nanoparticles and phosphorus flame retardant could act a barrier role by covering the carbon layer to isolate air and heat, thereby resulting in excellent anti-meltdrop properties. The simple modification method reported here realizes the collaborative modification of flame retardant and anti-meltdrop properties of phosphorous flame-retardant copolyesters by thermal cross-linking. 相似文献
52.
53.
为制备具有增强阻燃效果的皮革涂饰材料,本研究首先以天然石墨为原料,采用Hummers法制备氧化石墨烯,并采用NaBH4对其进行还原得到还原氧化石墨烯(rGO)。通过FTIR,XRD和TEM等对其进行表征。结果表明,成功制备了rGO纳米材料。随后,采用物理共混法将rGO引入天然蛋白质酪素体系,制备酪素基rGO复合乳液并将其应用于皮革涂饰,对涂饰后革样的阻燃性能、力学性能和耐干湿擦性能进行测试。结果表明,当rGO的含量为酪素体系溶质质量的0.5%时,与未含rGO的酪素体系相比,涂饰后革样的燃烧速率下降47.2%,极限氧指数(LOI)由24.2%增加至26.3%,热释放速率(HRR)下降53.1%,总热释放率(THR)也有所降低。rGO的引入对涂饰后革样的力学性能和耐干湿擦性能影响不大。 相似文献
54.
采用端羟基聚丁二烯(HTPB)剥离层状有机蒙脱土(OMMT)为纳米片层,并与异佛尔酮二异氰酸酯(IPDI)、二羟甲基丙酸(DMPA)等单体通过原位聚合法制备了OMMT纳米片改性的水性聚氨酯(OWPU)纳米乳液及胶膜。利用小角XRD、TEM、DLS、EDS、TGA、LOI、CONE以及SEM对样品的结构和性能进行了表征。结果表明,HTPB剥离的OMMT纳米片的衬度均匀,完整性较好;改性后OWPU的乳液粒径增大,胶膜的弹性模量、热稳定性、抗熔滴性和阻燃性能均得到明显地改善,其中弹性模量可提高59.4%,热释放速率峰值可降低36.9%;燃烧炭渣表面形貌显示,瓦片状蒙脱土相互穿插形成了具有团簇结构的蒙脱土覆盖层。 相似文献
55.
Birong Zeng Kaibin He Haiyang Wu Jianyu Ye Xianghong Zheng Weiang Luo Yiting Xu Conghui Yuan Lizong Dai 《大分子材料与工程》2021,306(6):2100012
A zirconium hybrid polyhedral oligomeric silsesquioxane derivative (Zr–POSS–bisDOPO) is synthesized by the corner-capping and Kabachnik–Fields reactions. It is characterized by Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (NMR), and then used as a flame retardant in diglycidyl ether of bisphenol A (DGEBA) to endow epoxy resin (EP) with flame retardancy. The flame retardancy, thermal stability, and mechanical properties of the cured EP/Zr–POSS–bisDOPO composites are investigated. The results show that when Zr–POSS–bisDOPO is added by 5–7 wt%, the EP/Zr–POSS–bisDOPO composites pass the UL-94 V-0 rating test. In addition, they have a better flame-retardant effect than pure EP. The combination of Zr atom embedded in the Si O cubic cage and the two phosphaphenanthrene substituent groups in one corner of cubic cage is expected to realize the Zr/Si/P ternary intramolecular hybrid synergistic effect and achieve the possibility of dispersing metal–POSS cages at a sub-micrometer-scale level into polymer matrix. It also proves that Zr–POSS–bisDOPO produces phosphorus-containing free radicals and terminates the chain reactions in gas phase. Meanwhile the Si O Si and Zr O units are retained in the solid phase, which promote the char formation and enhance the flame retardancy. This kind of Zr-doped POSS will be helpful for developing the new metal–POSS hybrid flame-retardant and polymer composites. 相似文献
56.
Jinhong Kim Junho Jang Sehui Yun Hyeon Deok Kim You Young Byun Yong Tae Park Jung Il Song Chungyeon Cho 《大分子材料与工程》2021,306(9):2100233
In an effort to develop highly functionalized flame retardant materials, hybrid nanocoatings are prepared by alternately depositing a positively charged polyaniline (PANi) and negatively charged montmorillonite (MMT) using the layer-by-layer (LbL) assembly technique. Carbon nanotubes (CNTs) are employed in polymer nanocomposites as effective reinforcement, where nanotubes are stabilized in MMT aqueous solution. The 3D structure and high density of CNTs deposited in the PANi/CNTs-MMT multilayers produce thicker and heavier coatings in comparison to the LbL assemblies without CNTs. Vertical and horizontal flame testing show that the incorporation of CNTs improves fire resistance. Additionally, cone calorimetry reveals that stacking two nanomaterials (MMT and CNTs) in a single coating shows a significant reduction in peak heat release rate (up to 51%), total smoke release (up to 47%), and total heat release (up to 37%) for the polyurethane foam. The enhancement of flame retardancy is attributed to a synergistic effect; MMT serves as a physical barrier that retards the diffusion of heat and gas. The addition of CNTs strengthens the thermal stability and high char yield. These results, coupled with the simplicity with which the LbL deposition is applied, present a viable alternative to halogen-free flame retardant nanocoatings to natural and synthetic fibers. 相似文献
57.
The design and application of bioderived flame retardants have been widely conducted to meet the concept of green and sustainable development. Here, self-assembly technique is used to prepare core–shell bioderived additives by using β-FeOOH as the core and polydopamine (PDA)/tannic acid (TA) bilayer as the shell, following adsorption of nickel ions to enhance the thermal stability, flame retardancy, and mechanical properties of epoxy resin (EP). The molecular structure of biobased resources is rich in hydroxyl groups and carbon content, which can be dehydrated and carbonized during combustion and promote the formation of robust protective char layer. With the addition of 5 wt% β-FeOOH@PTNi, the EP composites can pass V-0 rating in the UL-94 test. The peak heat release rate and total heat release decrease by 28.4% and 17.4% compared with pure EP. The bioderived nanorods can capture the oxygen free radicals, contributing to flame retarding in gaseous phase. Thus, the release of high-toxic CO and flammable gaseous is significantly suppressed. Besides, the storage modulus of EP composites increases by 16.0% with the addition of 5% β-FeOOH@PTNi compared with pure EP. This work provides a sustainable methodology for the design of bioderived flame retardants for EP. 相似文献
58.
There is a growing demand to develop epoxy resins (EP) with smoke suppression as well as satisfactory flame retardancy. Herein, bio-based cobalt alginate is successfully fabricated and incorporated into EP to prepare EP/Cobalt Alginate composites with better fire safety performance. The addition of cobalt alginate reduces the thermal-decomposition rate, temperature at maximum weight-loss rate of EP, whereas obviously improves the thermal stabilities at a higher temperature range. Furthermore, the addition of cobalt alginate substantially reduces the fire hazard of EP, resulting in 56.2% reduction in peak heat release rate, as well as 17.8% and 56.3% reduction in total smoke production and peak smoke production rate, respectively, compared with EP matrix. Moreover, the presence of cobalt alginate increases smoke-suppressant properties, according to the smoke density test. Additionally, the incorporation of cobalt alginate has no obviously destructive effect on the mechanical properties of EP, while EP/Cobalt Alginate-3 exhibits a 27.0% improvement in impact strength. In prospective, this study may provide a significant method for producing eco-friendly flame retardant EP. 相似文献
59.
M.J. Tsafack 《Surface & coatings technology》2006,201(6):2599-2610
The permanent fire proofing of textiles of natural origin such as cotton is still challenging because only a surface treatment can be applied. Moreover, to be resistant to washing or harsh weather conditions the flame retardant must be fixed strongly to the surface, most efficiently achieved via covalent bonds. For that purpose, the simultaneous grafting and polymerization of fire retardant monomers on cotton fabric induced by argon plasma have been investigated with four acrylate monomers containing phosphorus, diethyl(acryloyloxyethyl)phosphate (DEAEP), diethyl-2-(methacryloyloxyethyl)phosphate (DEMEP), diethyl(acryloyloxymethyl)phosphonate (DEAMP) and dimethyl(acryloyloxymethyl)phosphonate (DMAMP), which are known to be effective for this application. We also report the synthesis and the plasma-induced graft-polymerization (PIGP) of two new phosphoramidate monomers, diethyl(acryloyloxyethyl)phosphoramidate (DEAEPN) and acryloyloxy-1,3-bis(diethylphosphoramidate)propan (BisDEAEPN) on cotton fabrics. Their flame retardant effect was compared with the previously used acrylate phosphate and phosphonate monomers. DEAEPN and BisDEAEPN exhibit the highest LOI values (28.5 and 29.5 respectively). The good flame retardant properties of these phosphoramidate monomers are attributed to the presence of nitrogen which causes a synergistic enhancement in the efficiency of phosphorus-based flame retardants. The grafting and the polymerization processes taking place on the surface of the cotton textile were followed by weighing measurements, IR (ATR) spectroscopy and SEM. The fire retardant character of the treated fabrics was investigated by thermogravimetric analyses and LOI measurements. The durability of the treatment was investigated by using the accelerated method of laundering proposed by McSherry et al. 相似文献
60.