POLYMER DEGRADATION AND STABILITY
·
2024
·
IF 6.3
Ni Kang,Xulong Ma,Yonghang Zhang,Ou Zhao,Yang Min,Wei Zhao,Daming Ban
The intrinsic flammability and high smoke production are two major defects that epoxy resin (EP) must overcome during the practical application. However, few current studies have acknowledged in both fire resistance and smoke suppression performance, which is vitally interrelated with quality of char layers. Herein, a P/S-containing compounds (PODSE) was prepared via esterification and then supplemented with ammonium polyphosphate (APP) to develop an intumescent flame retardant for heightening the strength of char. With 20 wt% PODSE/APP, the peak of smoke produce rate (pSPR) and total smoke production (TSP) of EP3 reduced by 88.1 % and 87.0 %, respectively, indicative of superior smoke suppression performance. It attained a limited oxygen index (LOI) value of 40.0 % with V-0 rating during vertical burning test (UL-94) and the char residues at 700 °C increased from 15.8 % to 29.9 % compared with pure EP. More importantly, in order to figure out the reason for such highly-improved performance, the residual chars after cone calorimeter (CC) test were comprehensively investigated. The result showed that the internal chars of the samples modified by PODSE/APP exhibited honeycomb-like structure instead of irregular network structure of the one modified with single PODSE, endowing the char layers with higher expanded ratio and strength, which responded to excellent insulation effect. This finding provided theoretical and experimental basis for further exploration of P/S synergistic intumescent flame retardant.
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
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2019
·
IF 1.911
Shouwu Yu,Shujuan Xiao,Zewen Zhao,Xiaowen Huo,Junfu Wei
Dipentaerythritol (DPER), 4, 4′-diphenylmethanediisocyanate (MDI) and melamine (MEL) are used as raw materials to microencapsulate ammonium polyphosphate (MAPP) in situ polymerization. The MAPP is characterized by Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and thermal gravimetric analysis (TGA). The results show that the coating operation can effectively improve water resistance of ammonium polyphosphate (APP), and MAPP has higher residual rate than that of APP after combustion. The flame retardant action of MAPP and APP in polypropylene (PP) is investigated by the limited oxygen index (LOI), vertical burning test (UL-94), TGA, SEM, and cone calorimeter test (CCT). The LOI value of the PP/MAPP composite at the same loading is higher than that of PP/APP composite. UL 94 ratings of PP/MAPP composites are raised to V-0 at 20 wt% loading. The results of CCT also show that MAPP is more efficient than APP. The morphological structures observed by digital photos and SEM demonstrated that MAPP could be promoted to form the continuous and compact intumescent char layer. The flame retardant mechanism of PP/MAPP is also discussed.
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
·
2019
·
IF 8.355
Yubin Huang,Saihua Jiang,Runcan Liang,Ping Sun,Yun Hai,Lei Zhang
The use of intumescent flame-retardant (IFR) coatings is one of the most highly effective methods for polymeric materials to improve their fire safety. However, organic IFR coatings show “negative effect” in a large amount of heat and smoke release during the char-forming process. Developing nanocomposite coatings that can reduce their “negative effect” and simultaneously enhance the barrier effect of fireproof char layer is particularly desirable. Herein, a novel UV-curable IFR/MXene nanocomposite coating was developed by incorporation of surface-modified MXene nanosheets in the IFR coating system, and then constructed on the surface of rigid polyurethane (RPU) foam to fabricate coated RPU foams via spray-coating and UV-cured process. The IFR/MXene coated RPU foams show a fast self-extinguished behavior and a remarked decrease in heat and smoke production, indicating the great improvement of RPU fire safety in building. The fireproof layers combined with expanded char and MXene jammed networks generated rapidly during combustion can serve as physical shield to effectively delay the release of heat and volatile products, protecting the underlying substrate from further burning. Moreover, the mechanical properties and dispersion are enhanced due to the co-cross-linking networks between the IFR coating and MXene nanosheets. As a new member of the 2D nanomaterials, MXene nanosheets have potential to be a new choice for developing high-performance nanocomposite coating for polymers to reduce their risk of fire hazard.
研究领域:
材料科学
·
消防安全
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Jinghong Liu,Zhuojian He,Guohui Wu,Xiaoqing Zhang,Chen Zhao,Caihong Lei
Developing bioresourced epoxy resin with excellent flame retardancy is challenging for satisfying environmental and fire hazard requirements. Herein, a novel monomer with six functional epoxy groups was successfully synthesized by combining eugenol with hexachlorocyclotriphosphazene. Using aliphatic diamine as a curing agent, a novel epoxy of EHPE-D230 was prepared, and its properties were systematically evaluated. Compared with commercial epoxy resin (E51-D230), EHEP-D230 possessed a higher tensile strength (56.7 to 64.2 MPa) and better thermal resistance (T α = 85 to 119 °C). Moreover, EHEP-D230 exhibited a high limiting oxygen index value of 31%, and it passed the UL94 V-0 test without any after-flame time. Cone calorimeter test indicated that the peak value of the heat release rate, total heat release, and total smoke production for EHEP-D230 reduced significantly by 66%, 65%, and 78%, respectively, compared with those of E51-D230. The EHEP-D230 residual char exhibited a compact and continuous exterior structure and a honeycomb-like hollow vesicle interior structure. This unique intumescent char endowed EHEP-D230 with excellent flame retardancy and smoke suppression, rendering it a potential candidate for fire-resistant applications.
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
JOURNAL OF MATERIALS SCIENCE
·
2021
·Vol. 56
·期 30
·16999-17010
·
IF 4.22
Xu Yue,Liu Lubin,Yan Chentao,Hong Yukai,Xu Miaojun,Qian Lijun,Li Bin
In the field of electronic and electrical applications, it has always been a challenge to synchronously improve the flame-retardant and smoke-suppression properties for epoxy resins. In this research, a novel flame-retardant phosphonic acid piperazine salt (PTPAP) was successfully synthesized in an environmentally friendly manner and used to fabricate flame-retardant EP thermosets. The fire safety and flame-retardant mechanisms of EP/PTPAP thermosets were detailedly studied. When merely 6 wt% PTPAP was introduced into EP substrate, the EP/PTPAP thermosets gained UL-94V-0 grade and their LOI value improved from 21.3% of pure EP to 28.3% with the increase of 32.9%. The introduction of PTPAP promoted the premature degradation and charring of EP matrix, and the intumescent, compact, and sealed char layer was produced on the surface of EP/PTPAP thermosets during combustion. Besides, PTPAP decomposed and produced the PO· and inert gases, which efficaciously exerted the free radical trapping and dilution effect in vapor phase. Therefore, the emission of smoke and heat was distinctly constrained and the EP/PTPAP thermosets was endowed with the superior fire safety. This flame-retardant EP/PTPAP thermosets showed broad application prospects under the environment of sustainable development because of the eco-friendly and simplicity of the synthesis of PTPAP. Graphical abstract
研究领域:
材料科学
·
化学工程
·
消防安全
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2018
·
IF 5.091
Dongmei Lin,Xingrong Zeng,Hongqiang Li,Xuejun Lai,Tongyi Wu
Waterproof and flame-retardant fabrics are widely utilized in many fields, such as automotive interiors, indoor decorations, outdoor clothing and tents. Herein, a facile one-pot sol-gel approach was developed to construct superhydrophobic and flame-retardant (SFR) coatings on cotton fabrics. The cotton fabric was activated by O 2 plasma and then immersed into the ethanol suspension containing tetraethoxysilane (TEOS), hydroxyl-terminated polydimethylsiloxane (HPDMS) and ammonium polyphosphate (APP). The hydrogen bonding interaction between APP and cellulose motivated the APP to attach to the cotton fibers during the initial stirring process. After the addition of ammonia, the in situ sol-gel reaction of TEOS and HPDMS was initiated to generate polydimethylsiloxane-silica hybrid (PDMS-silica). The micro-nano structured composite coating on cotton fabric was successfully fabricated by the PDMS-silica and APP. The SFR cotton fabric showed outstanding durability and self-cleaning ability with a water contact angle (WCA) above 160°. When exposed to fire, the SFR cotton fabric quickly charred to extinguish the fire by generating a dense intumescent char layer under the physical barrier effect of PDMS-silica and the intumescent flame-retardant effect of APP. This one-pot approach for fabricating SFR cotton fabric is simple, cost-effective and timesaving, demonstrating significant advantages in practical production.
研究领域:
材料科学
·
纺织工程
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2022
·
IF 5.204
Yang Zhang,Yuanlu Cui,Jiyu He,Rongjie Yang
A series of novel 1-oxo-4-hydroxymethyl-2,6,7-trioxy-1-phosphabicyclo[2,2,2]octane (PEPA)-functionalized metallophthalocyanines (PEPA-MPcs, M = Al, Co, Ni, Zn, and Ce) have been successfully synthesized and characterized. The obtained PEPA-MPcs were added to epoxy resin (EP) to prepare a variety of flame retardant composites (EPP-MPcs) and their thermal behavior and flame retardancy were investigated using thermogravimetric analysis (TGA), the limiting oxygen index (LOI), and cone calorimetry. The flame-retardant mechanism was systematically analyzed in the gas and condensed phases, respectively. The highest LOI value of EP containing 2 wt.% PEPA-MPcs was increased by 19% to 27.6% when compared to pure EP. The peak of heat release rate (pHRR) and the total heat release (THR) values observed for EPP-AlPc were reduced by 64.3% and 48.6%, respectively. The main flame retardant mechanism of the PEPA-MPcs is the synergistic effect of the P and N atoms, including the dilution of highly non-flammable gases in the gas phase and the formation of an intumescent char layer from the condensed phase. Furthermore, the char residues of the EPP-MPcs were significantly increased via the catalysis and surface enrichment of the metal atoms, which reduced the fire hazards of the EP composites. In addition, the EPP-MPcs exhibit excellent mechanical properties and uniform dispersions. This work provides a new approach to the preparation of metal containing/non–halogen/phosphorus-containing flame retardants.
研究领域:
材料科学
·
化学
·
高分子科学
·
消防安全工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2020
·
IF 4.032
Peng Wang,Hang Xiao,Chao Duan,Bo Wen,Zongxin Li
A sulfathiazole derivative with phosphaphenanthrene group (STZ) was successfully synthesized by covalently bonding DOPO and imine intermediate obtained from the condensation of sulfathiazole with p -hydroxybenzaldehyde. Its effect on the thermal, flame-retardant and mechanical properties of epoxy thermosets were comprehensively studied. The presence of STZ decreased the initial degradation temperature and glass transition temperature ( T g ) of epoxy thermoset. STZ significantly improved the flame retardancy and fire safety of epoxy thermoset. With the addition of only 4 wt% STZ, the modified epoxy thermoset achieved an LOI value of 29.1% and V-0 rating in UL-94 test. Moreover, the peak heat release rate (PHRR) and total heat release (THR) in cone calorimeter test were decreased by 34.4% and 32.1% in comparison with those of pure epoxy thermoset. STZ showed high flame-retardant activity not only by releasing nonflammable gases and phosphorous radicals in the gas phase, but also by promoting the formation of dense and intumescent char layer with honeycomb-like hollow structure inside in the condensed phase. Because of the strong intermolecular action between STZ and epoxy macromolecular chain, the presence of STZ increased the tensile strength , while decreased the elongation at break of epoxy thermoset.
研究领域:
材料科学
·
化学
·
高分子科学
·
消防安全工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2016
·
IF 3.12
Shuang Yang,Qiaoxin Zhang,Yefa Hu
A novel halogen-free flame retardant (DTB) containing phosphorus, nitrogen and boron was successfully synthesized. The chemical structure of DTB was characterized by Fourier transform infrared spectroscopy (FTIR), 1 H and 31 P nuclear magnetic resonance (NMR). DTB was then blended with diglycidyl ether of bisphenol-A (DGEBA) to prepare flame-retardant epoxy resins . Thermal properties, flame retardancy and combustion behavior of the cured EP thermosets were investigated by thermogravimetric analysis (TGA), limited oxygen index (LOI) measurement, UL94 vertical burning test and cone calorimeter test. The results indicated that DTB significantly improved the flame retardancy as well as smoke inhibition performance of EP/DTB thermosets. Compared with the neat EP thermoset, the LOI of EP/DTB-3 thermoset was increased to 35.6% and the sample reached UL94 V-0 rating; the average of heat release rate (av-HRR), total heat release (THR) and total smoke production (TSP) of EP/DTB-3 thermoset were decreased by 33.3%, 33.0% and 35.5%, respectively. TGA results indicated that the char yields of EP/DTB thermosets were increased by 45.1–72.8% compared with that of the neat EP thermoset. The FTIR, SEM-EDX and Py-GC/MS results indicated that DTB contributed to form intumescent and glassy char layers and decomposed to generate free radicals with quenching effect. DTB was effective radical trapper as well as efficient charring agent for epoxy resin and exerted flame-retardant effect in gaseous and condensed phases simultaneously.
研究领域:
材料科学
·
高分子化学
·
消防安全工程
✓ 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）