SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Dewen Zhou,Qinglong Luo,Guoliang Nie,Mingzhe Dong,Xiao Du,Haining Liu,Zhijian Wu,Jun Li
High-quality, low-chloride zinc borate is a low-smoke, non-toxic and environmentally friendly flame retardant with improved electrical properties for printed circuit board (PCB), so it can be used as a new type of flame retardant to replace brominated flame retardants. However, the chlorine content of zinc borate itself is high, and long-term use of zinc borate circuit boards will cause leakage and may cause a fire. To solve this problem, commercially available zinc borate (analytically pure) with a high chlorine content was used for the study. The presence of chloride ions in zinc borate was determined by X-ray photoelectron spectroscopy (XPS) and point of zero charge (PZC) and found to be mainly in the form of soluble salts and electrostatic adsorption. Based on the existing form of chloride ions, the synergistic technology of electrodialysis and washing with Na 2 CO 3 solutions was used to remove most of the chloride ions from zinc borate, and the removal effect was up to 94.03%. The optimal process was optimized by the reaction surface curve method, the separation kinetics and electrical properties were investigated, and the membrane lifetime was evaluated. Zinc borate can be used as a flame retardant in printed circuit boards after contrast treatment. This study provides an important reference and guide for the removal of impurity ions from other inorganic flame retardants. In addition, it provides technical support for the production of high-quality zinc borate flame retardants.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2022
·
IF 5.204
Yong Guo,Hu Rong,Zhongwei Chen,Tingting Chen,Yuan Yu,Xida Zhang,Yanpeng Chu,Qingwu Zhang,Changxin Li,Juncheng Jiang
A novel reactive flame retardant (PABO) was synthesized via a one-pot reaction from para-aminobenzonitrile, p-hydroxy benzaldehyde and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and applied on epoxy resin (EP). The curing state of the EP mixture with the addition of PABO was excellent as detected by the cure index (CI). Thermogravimetric analysis showed that compared with DOPO, PABO possessed a higher degradation temperature, a lower thermal decomposition rate and the Char 800 (char residues at 800°C) increased from 1.5 to 26.5 wt%. The EP/PABO-5 with only 5 wt% PABO content attained a limiting oxygen index of 32.7% and possessed the UL-94 V-0 level. The calculated flame retardant index (FIGRA) showed that the fire safety of EP/PABO-5 was superior to that of EP/DOPO-5. For flame retardant mechanism, in the gas phase, PABO possessed the function of retarding the thermo-oxidative decomposition of EP, the quenching effect of phosphorus radicals and the diluting effect of non-combustible nitrogen-containing gas. In the condensed phase, the trimerization reaction of nitrile groups happened and the existence of the phosphaphenanthrene group together promoted the formation of a stable char layer, which could obstruct the transfer of heat and oxygen.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
·
2023
·
IF 5.1
Wei Zhang,Bingtao Wang,Yan Xia,Wei Wang,Zhenghong Guo,Zhengping Fang,Juan Li
It is a great challenge to prepare polyamide 6 (PA6) compounds with outstanding fire safety and mechanical properties. In this research, a flame retardant containing P/N/S elements (SNDP) was synthesized using 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), 2-thiophene-carboxaldehyde and 4-aminobenzonitrile. The PA6/SNDP compounds were prepared using a melt blending method. Two chain extenders were incorporated into PA6/SNDP compounds to adjust their mechanical properties. The results suggest that PA6 compound with 10 wt% SNDP obtains a UL-94 V-0 rating (1.6 mm) and a limiting oxygen index (LOI) value of 27.4 vol%. SNDP induces the degradation of PA6 and decreases its mechanical properties. While the two chain extenders have reinforced effects on PA6/SNDP and this effect of 1,3-phenylene-bis-oxazoline is superior to another one. Moreover, the main flame-retardant mode of actions for SNDP in PA6 is gas-phase effect, including scavenging free radicals and diluting flammable gases.
研究领域:
材料科学
·
防火安全工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMER ENGINEERING AND SCIENCE
·
2023
·Vol. 63
·期 11
·3614-3624
·
IF 3.2
Menghua Ma,Liangbing Zhao,Guangrui Wang,Cheng Song,Rui Chen
A novel fire-resistant epoxy resin (EP) material has been prepared using EP, 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), maleic anhydride, and 2-aminobenzothiazole. Maleithiazolephosphaphenanthrene (MSD) was synthesized and its chemical structure was characterized using infrared spectroscopy (IR) and nuclear magnetic resonance (NMR). Fire-resistant additive MSD was introduced into EP. The flammability and mechanical properties of the modified EP materials were then investigated using limiting oxygen index (LOI), UL-94 vertical burning, cone calorimeter (CC), tensile, three-point bending, and izod unnotched impact tests. EP blend containing 4%MSD displayed a UL-94 V-0 rating and an LOI value of 32.2%. Heat release and smoke release determined using cone calorimeter for the sample containing 4% MSD were lower than the sample of EP alone. Further, introduction of 4% MSD to EP material improved its izod impact, tensile strength, and flexural strength by 13.3%, 13.9%, and 21.6%, respectively. Inferences for the mode of fire-resistant action were available from MSD, XPS, SEM, Raman, and Py-GC/MS. MSD has a positive effect on fire resistance in both the condensed phase and gas phase. Highlights A novel flame-retardant (MSD) was synthesized. MSD endowed EP with excellent fire safety and improved mechanical properties. MSD shortened solidification time of EP during preparation. MSD plays a flame-retardant role in both condensed and gaseous phases.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Xi Yu,Lu He,Xiaofeng Zhang,Gege Bao,Rong Zhang,Xiaobei Jin,Daochun Qin
Bamboo fibers (BF), as an important sustainable natural material, are becoming a hot alternative to synthetic fibers for the reinforcement of polypropylene (PP)-based composites. However, the weak interfacial compatibility between BF and PP as matrix and their inherent flammability limit the practical application of BF/PP composites (BPC). Here, a fire-safe BPC was fabricated by constructing flame-retardant interfacial layers containing tannic acid (TA)-Fe 3+ complex and halloysite nanotubes (HNTs) on the fiber matrix followed by a hot-pressing process. The results showed that the interfacial chelating of TA with Fe 3+ improved the dispersion of HNTs on the fibers and the interfacial interactions within the fiber matrix, resulting in the as-fabricated composite with significantly improved mechanical properties and water resistance. In addition, the flame-retardant composite exhibited higher thermal stability and enhanced residual char content. Moreover, the composite possessed significant flame-retardant performances with a reduction of 23.75 % in the total heat release and 32.44 % in the total smoke production, respectively, owing to the flame retarding in gaseous phase and condensed phase of TA-Fe 3+ @HNTs layers. This work offers a green and eco-friendly strategy to address the inherent problems of BPC material in terms of fire safety and interfacial compatibility, thus broadening their applications in the automotive interior and construction industries.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COMPOSITES PART B-ENGINEERING
·
2022
·
IF 11.322
Xia Zhou,Shuilai Qiu,Lingxin He,Wei Cai,Fukai Chu,Yulu Zhu,Xin Jiang,Lei Song,Yuan Hu
As known, the poor toughness and low fire safety of bismaleimide resin (BMI) has become a problem which restricts its further application in advanced high-performance field. Therefore, a novel allyl-functionalized linear polyphosphazene (PMAP) was designed and synthesized. With inclusion of 3wt% PMAP , the peak heat release rate (PHRR) and total smoke production (TSP) of BMI/PMAP-3 are reduced by 51.3% and 17.8%, respectively. And the residual char of BMI/PMAP increases significantly as well. Furthermore, the flame-retardant mechanism of BMI/PMAP is proposed. In condensed phase, PMAP can participate in the formation of residual char of BMI/PMAP and the char layer is with an excellent physical barrier effect by the existence of phosphorus oxygen and phosphorus nitrogen cross-linking substances. In gas phase, phosphorous oxygen free radical is also generated from PMAP, which can capture gas-phase chain free radicals and inhibit gas-phase combustion. Moreover, the impact strength of BMI/PMAP-3 increases by 85.3%, which indicates that the toughness of BMI/PMAP is effectively enhanced. The toughening mechanism of PMAP on BMI can be assigned to elastomer toughening. Therefore, with modification of PMAP, BMI/PMAP is indeed of better comprehensive performance, which is in line with expectation and provides inspiration for the simultaneous flame-retardant and toughening modification of BMI.
研究领域:
材料科学
·
高分子化学
·
阻燃材料
✓ 已验证
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2024
·
IF 7.4
Yao Yuan,Lulu Xu,Wei Wang
The extensive usage of rigid polyurethane foam (RPUF) as an energy-saving building materials in construction has raised concerns about fire risks and toxic hazards. To address these challenges, a melamine-derived polyol (MADP) was synthesized using the Mannich reaction, resulting in inherently flame-retardant RPUF materials with the introduction of flame-retardant functional groups. Furthermore, a novel MoS 2 -Cu 2 O nanohybrid was prepared and employed to enhance flame retardancy and suppress smoke toxicity in RPUF through a cooperative effect with expandable graphite (EG). The resulting M-RPUF/EG/MoS 2 -Cu 2 O nanocomposite exhibited remarkable fire safety, as evidenced by significant reductions in peak heat release rate (PHRR), total heat release (THR), total smoke production (TSP), and peak carbon monoxide (CO) release, amounting to 76.9 %, 64 %, 82 %, and 99 % respectively, compared to pristine RPUF. Furthermore, the nanocomposite effectively addressed interfacial defects and significantly enhanced the mechanical property and thermal stability. The significant improvement in fire safety is mainly ascribed to the catalytic charring effect of MADP and EG, as well as the catalytic oxidation of MoS 2 -Cu 2 O nanohybrids, resulting in the formation of a thermally stable protective layer in the condensed phase. Based on these results, the integration of the tri-phase flame retardant system holds great potential for advancing the development of fire-safe polyurethane materials.
研究领域:
材料科学
·
消防安全
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF PHOTOPOLYMER SCIENCE AND TECHNOLOGY
·
2020
·Vol. 32
·期 6
·769-778
·
IF 0.909
Xiujuan Tian,Qingqing Yin,Zhongwei Wang
A type of reactive phosphorus based flame retardant, hydroxy(4-hydroxyphenyl)methyl)diphenylphosphine oxide (DPO-H), was synthesized and characterized by Fourier Transform Infrared (FTIR) and Nuclear Magnetic Resonance (NMR) spectroscopies. 4,4′-Diaminodiphenylsulfone (DDS) was used as the curing agent and DPO-H was used as the reactive flame retardant and co-curing to prepare the flame-retardant epoxy resins with different P contents. It can be observed that the introduction of DPO-H could enhance the transparency of epoxy resin. Flame-retardant epoxy resin samples were investigated by limit oxygen index (LOI) test, vertical burning (UL-94) testing, cone calorimetry test and thermogravimetric analysis (TGA). The results indicated that DPO-H can increase the flame retardation and carbon formation of epoxy resin. The flame-retardant epoxy resin sample with P content of 0.5 wt% can reach UL-94 V-0 rate, and LOI value increased to 29.6%. The flame-retardant mechanism of the DPO-H modified flame-retardant epoxy resin was analyzed by thermogravimetry-infrared combination (TG-IR), pyrolysis gas chromatography mass spectrum (PY/GC-MS) and scanning electron microscope (SEM). The results showed that the introduction of DPO-H can inhibit the pyrolysis of epoxy resin effectively. Epoxy resin modified by DPO-H had evident flame-retardant effect both in gas phase and condensation phase.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2022
·
IF 5.204
Congling Shi,Mei Wan,Zhengbo Hou,Xiaodong Qian,Honglei Che,Yueping Qin,Jingyun Jing,Jian Li,Fei Ren,Bin Yu,Ningning Hong
Thermoplastic polyurethane (TPU) is the most used polyurethane, but its highly flammable characteristic restricts its extensive use. In this work, Co-MOF@MXene hybrids flame retardants were synthesized and incorporated into TPU . The flame-retardant characteristics of TPU composites were investigated by cone calorimeter test and thermogravimetric analyzer. Compared with TPU, the peak heat release rate and total heat release rate of TPU/Co-MOF@MXene composites were reduced by 28.3% and 14.5%, respectively; and the smoke production rate and total smoke production of the composites with only 2 wt% Co-MOF@MXene hybrids were also reduced by 58.8% and 47.5%, respectively. Furthermore, the char residues of TPU/Co-MOF@MXene composites were about 2 times that of pure TPU. Systematical characterizations were then carried out to investigate the flame retardant mechanism of Co-MOF@MXene hybrids, highlighting the barrier effects of MXene combined with the catalytic effect of Ti and Co. The hybrids flame retardants greatly benefit the further development of TPU nanocomposites.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Long Xia,Yan Lv,Zhongxi Miao,Lili Luo,Weiang Luo,Yiting Xu,Conghui Yuan,Birong Zeng,Lizong Dai
Facile fabrication of fire-warning sensors with low-cost and high-strength has always been a considerable challenge for materials scientists. Herein, Carbon black (CB) nanoparticles with core-shell structure (denoted as CB@KF) were prepared by in-situ polymerization. And a novel fire-warning sensor (denoted as CB@KF-CF) with temperature sensing, fire-warning, flexibility and high strength was fabricated by coating a flame retardant coating, which consists of PVA, CB@KF, and Carbon nanotubes (CNT) on cotton fabric. Benefiting from the flame retardancy and carbonization performance of CB@KF, CB@KF-CF possessed much better flame retardancy and fire-warning properties. Especially, CB@KF-CF exhibited a shorter alarm time to abnormal high temperature (350 °C) and fire, which can warn at 8 s and 4 s respectively. Meanwhile, the char length of CB@KF-CF was 7.8 cm after the Vertical flame test (VFT) and the Total heat release rate (THR) of CB@KF-CF was also reduced by more than 50%. Ultimately, the formation mechanism of the dense char layer and the conductive paths were also illustrated. These results show that the preparation of fire-warning sensor described in this paper has broad application prospects.
研究领域:
材料科学
·
消防安全
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2019
·
IF 7.65
Siqi Huo,Shuang Yang,Jun Wang,Jianwen Cheng,Qianqian Zhang,Yefa Hu,Guoping Ding,Qiaoxin Zhang,Pingan Song
The development of phosphorus-containing flame retardants combining good compatibility with matrix, low curing temperature, and mechanically reinforcing effect has remained a major challenge. Herein, we reported the synthesis of a liquid flame-retardant curing agent (DA) via the nucleophilic substitution between diphenylphosphinic chloride and 1-(3-aminopropyl)-imidazole (AI). DA exhibited good blending and latency towards epoxy resin (EP) at room temperature. According to DSC studies, DA could rapidly cure EP at moderate temperature. Compared with EP/AI sample, EP/DA samples displayed comparable or higher glass transition temperature ( T g ) and enhanced mechanical properties due to the introduction of rigid diphenylphosphinyl group and improved cross-linking density. Moreover, DA improved the flame-retardant performances of EP thermoset. For instance, the LOI and UL94 rating of EP/DA-16 sample achieved 37.2 % and V-0, respectively. In addition, the peak of heat release rate (PHRR), average of heat release rate (AHRR), fire growth rate (FIGRA), and total heat release (THR) for EP/DA-16 sample reduced by 32 %, 42 %, 28 % and 27 % in comparison to EP/AI sample, respectively. DA was characterized by its good compatibility with EP, moderate curing temperature, fast curing rate, suitable thermal latency, mechanical reinforcing and flame-retardant effects, and thus it had a broad application prospect in various industrial fields.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Haiyang Wu,Birong Zeng,Jinmei Chen,Tong Wu,Yuntong Li,Yongzhou Liu,Lizong Dai
A novel metal–organic-inorganic ternary intramolecular hybrid of N,N′-bis(methylene)-bis(dibenz[C,E][1,2]oxaphosphorin6-oxide)-propylisobutyl-amino-titanium-polyhedral oligomeric silsesquioxanes (Ti-POSS-bisDOPO) was synthesized via a feasible route including the corner-opening, corner-capping and Kabachnik-Fields reactions. The uniqueness of this compound lies in its structural design and has the function of flame retardant. Firstly, one Ti atom has been embedded into the polyhedral oligomeric silsesquioxanes (POSS) cage framework and two dibenz[C,E][1,2]oxaphosphorin6-oxide (DOPO) units with anti-burning functionality have been linked to the aminopropyl group on the corner of siliceous cage. For each molecule, the affinities of Ti-embedded POSS part and DOPO unit are different, which make Ti-POSS-bisDOPO to show the amphiphilicity. Therefore, Ti-POSS-bisDOPO could self-assemble into nanoparticle and achieve good dispersion in epoxy matrix with a particle size varying from 150 nm to 1.5 μm. Secondly, when Ti-POSS-bisDOPO was incorporated into EP matrix, the prepared EP/Ti-POSS-bisDOPO composites exhibited good comprehensive performances. Compared with pure EP, both limited oxygen index and char yield of EP/Ti-POSS-bisDOPO composites were increased greatly at a loading range of 1.5 wt%–6.0 wt%. Meanwhile, the corresponding heat release and smoke production of EP/Ti-POSS-bisDOPO were all reduced. It was observed that the interior layers of char residues were honeycomb-like multilayer structures and the exterior layers were compact, which could effectively hinder the heat transfer and gas diffusion by a barrier effect. Besides, when Ti was doped into the vertex of siliceous cage, it worked by catalyzing char formation, producing thermodynamically stable TiO 2 , and enhancing the flame retardancy. It was deduced that both condensed-phase and gas-phase flame-retardancy made contributions to the flame retardant mechanism. Overall, the metal-embedded and phosphorus-modified Ti-POSS-bisDOPO was a new kind of promising fire retardants in the field of non-halogen flame-retardant polymers.
研究领域:
材料科学
·
化学工程
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）