POLYMER DEGRADATION AND STABILITY
·
2025
·
IF 7.4
Shiya Wang,Miaojun Xu,Wei Huang,Yingke Zhu,Juan Li,Peng Chen
Polyamide 56 (PA56) is a polyamide based on bio-based chemical and has attracted widespread attentions. In this paper, a series of phosphomolybdates (POMs) with Keggin structure were incorporated into PA56 to modify its flame-retardant properties. Different POMs show different effects on the flame-retardant efficiency in PA56. A small amount of 3 wt% sodium phosphomolybdate (PMoNa) or nickel phosphomolybdate (PMoNi) enable PA56 to achieve the UL-94 V-0 rating, while the samples containing other POMs are not classified in the test. The POMs promote the degradation of PA56 at low temperature and char formation at high temperature, and improves the thermal stability in air. Especially, the PMoNa and PMoNi restrain the release of heat, flammable volatiles and toxic gas by forming more char and changing the pyrolysis pathway during combustion, thus modify the flame retardancy of PA56 effectively. The mechanical properties are deteriorated more or less which need to be modified further.
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
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Lin Chen,Dan Zhao,Xiu-Li Wang,Yu-Zhong Wang
Frequent fire accidents and increasing environmental/health issues call for more durable and safer firefighting strategy for polymeric materials. Widely used small-molecule flame retardants are limited for their damage to thermal/mechanical properties, poor durability, undesirable persistence, bio-accumulation and toxicity (PBT). Herein, a novel macromolecular flame retardant , arylamine-DOPO-bearing polyphosphoester (PPDSP) has been synthesized and added to the unsaturated polyester (UP). On the one hand, hydrogen bond between arylamine group of PPDSP and UP network enhances the interchain interaction and compatibility. On the other hand, the phosphoester and DOPO groups can generate high-oxidized phosphorus-containing acids at high temperature, which further catalyze the dehydration reaction of arylamine and UP matrix into dense char-layers and exert the synergistic charring effect. By integrating the hydrogen bond and synergistic charring effects into PPDSP macromolecule, the obtained UP/PPDSP resins exhibit excellent fire safety, flame-retardant durability, heat-resistance and impact strength. Compared with UP, the T g and T 5% of UP/PPDSP20 are increased by 11 °C and 20 °C, respectively. The LOI value reaches 27.3%, the UL-94 rating is V-0 and the peak heat release rate is reduced by 58%. Even after one year of normal storage or one week of water soaking, the original flame retardant performance is maintained. Hence, this macromolecular firefighting strategy provides an efficient, durable and green pathway for improving the fire safety of polymers.
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
COMPOSITES PART B-ENGINEERING
·
2022
·
IF 11.322
Shuang He,Cong Deng,Ze-Yong Zhao,Zi-Xun Chen,Yu-Zhong Wang
Currently, the promotion of flame retardancy is facing apparent decrease of mechanical properties for polyolefin , leading to an unresolved contradiction in this field. In this work, novel hyperbranched polyamide-amine based phosphorous-containing flame retardant PPAM-AT was designed to fabricate flame-retarded polypropylene (PP). Interestedly, when the flame retardancy of PP was greatly improved after incorporation of PPAM-AT, mechanical properties of flame-retarded PP were barely damaged compared with corresponding properties of neat PP. At 15% PPAM-AT, the limiting oxygen index (LOI) of PP/PPAM-AT 15 reached 30% and the highest V-0 grade was achieved in the burning test; the peak of heat release rate (PHRR) and fire growth rate of PP/PPAM-AT 15 were decreased by 83.8% and 60.7% in comparison with corresponding values of neat PP. Meanwhile, tensile strength and elongation at break for PP/PPAM-AT 15 maintained at 46.9 MPa and 551.3%, respectively, keeping at a comparative level with that of PP. Analysis on flame-retardant mechanism confirmed that typical intumescent flame retardation played a vital role for the excellent fire safety of PP/PPAM-AT. The reason for excellent mechanical properties of flame-retarded PP/PPAM-AT is ascribed to the multiple factors such as the change in the crystallization of PP, excellent energy-dissipating ability of PPAM-AT, and so on. This work demonstrated that hyperbranched polyamide-amine based phosphorous-containing flame retardant with unique chemical structure may achieve simultaneous flame retardancy and high performance of polypropylene, which opens a new pathway to solve the contradiction between flame retardancy and high performance of polyolefin.
研究领域:
材料科学
·
高分子化学
·
防火材料
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULAR MATERIALS AND ENGINEERING
·
2022
·Vol. 307
·期 11
·2200408
·
IF 4.402
Wen-Hua Zhao,Jing-Wen Wang,Guo-Chao Zhuang,Dong-Yue Liu,Chuang-Chuang Sun
A reactive flame retardant (DTP) is successfully synthesized and characterized, and then incorporated into epoxy resin (EP) as a co-curing agent. The thermal stabilities and flame-retardant properties of epoxy thermosets are evaluated. Compared to neat EP, the thermogravimetric analysis (TG) results show that the thermal decomposition rate of EP/DTP is reduced by 45% and the char yield at 750 °C is increased by 67%, when the addition amount of DTP is 12 wt%. In the cone calorimetry test (CCT), the values of the peak of heat release rate (pk-HRR), total heat release (THR), total smoke produce (TSP), and average of effective heat combustion (av-EHC) of EP-DTP-12 are exhibited a reduction of 36.6%, 26.4%, 40.5%, and 23.6% relative to neat EP, respectively. Meanwhile, the value of the limiting oxygen index (LOI) of EP/DTP-12 can reach 34.83%, and 6 wt% or more loading of DTP make EP/DTP pass the V-0 rating in the UL-94 test. Moreover, the flame-retardant mechanism is investigated by thermogravimetric analysis/infrared spectrometry (TG-IR) and scanning electron microscopy (SEM), which can be summarized into two aspects: the quenching effect of phosphorus-containing radicals and diluting effect of nonflammable gases in the gas phase, and the barrier effect of char layer in the condensed phase.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2018
·
IF 3.193
Junling Wang,Chao Ma,Peilong Wang,Shuilai Qiu,Wei Cai,Yuan Hu
A novel phosphorus-containing compound (DOPO-THPO) is synthesized via the Atherton-Todd-reaction between 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and trihydroxymethylphosphine oxide (THPO), and then employed as flame retardant for diglycidyl ether of bisphenol A/4-4 diaminodiphenylmethane epoxy resin (DGEBA/DDM). Based on the ultra-low phosphorus loading, the highly efficient flame retarded epoxy resin (EP) systems are successfully established in this work. Remarkable improvements in the limited oxygen index (LOI) values and UL-94 rating of flame retarded EP systems are observed. In detail, when the phosphorus content is only 0.33 wt%, the EP composite receives V-0 rating in the UL-94 vertical burning test with LOI value of 30%. Heat release of EP composites is obviously inhibited with the formation of intumescent char residue. Furthermore, TG-IR result of DOPO-THPO shows the generation of phosphorus containing products, which may provide a gaseous phase flame retardant function on EP. This work may open the new door for the construction of highly efficient flame retardant EP system based on the ultra-low phosphorus loading.
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
·
2020
·
IF 4.032
Hao Wang,Shan Li,Zongmin Zhu,Xianze Yin,Luoxin Wang,Yunxuan Weng,Xuyi Wang
A novel flame retardant POBDBI was generated by the reaction of p-dibenzaldehyde, 5-amino-2-benzimidazolinone and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), and employed to epoxy resin. The structure of POBDBI was measured by FT-IR and NMR tests. Then flame-retardant EP was fabricated by using POBDBI as a flame-retardant. The thermal stability, flame-retardant performance and fire behavior were investigated by a serious of comprehensive instruments. Combustion tests show the flame-retardant performance of composite materials has been significantly improved. For example, the EP/POBDBI-1.0 with the phosphorus content of 1.0% accorded a V-0 rating and its limiting oxygen index (LOI) value increased to 36.5%. Besides, total smoke production (TSP), peak heat release rate (PHRR) and total heat release (THR) of EP/POBDBI-1.0 dropped significantly, and the corresponding values were decreased by 48.4%, 48.9% and 8.7%, respectively. At the same time, the composition, morphology of chars and gaseous products of POBDBI were studied by X-ray photoelectron spectroscopy (XPS), FT-IR, scanning electron microscope (SEM) and Py-GC/MS. These results presented that POBDBI could not only exerted free radical capture effect, but also enhanced the density of char residue.
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
·
2023
·
IF 5.9
Wei Tang,Lijun Qian,Silvia González Prolongo,De-Yi Wang
In this work, small amounts of piperazine/phenyl-silicon charring skeleton NSi-n (n=1, 2, 3) with varied aggregation degrees were respectively inserted into a hydrogen-bonded macromolecule fabricated with melamine and cyanuric acid, to prepare a series of nitrogen/silicon-based macromolecules MNSi-n (n=1, 2, 3), which achieved the efficient charring flame retardant effect of MNSi-n/ammonium polyphosphate (APP) in polypropylene (PP). Due to the formation of compact barrier char layers with rich phosphorus and silicon contents, (MNSi-n/APP)/PP performed higher limited oxygen index, glow-wire flammable index and UL 94 V-0 level, and also exhibited lower heat release rate. Comparatively, the melamine cyanurate macromolecule without NSi-n skeleton with APP only formed ineffective char layers and weaker flame retardancy. More importantly, the higher aggregation degree of piperazine and phenyl-silicon groups in MNSi-n apparently led to higher intumescent flame retardant efficiency. The high aggregation degree of NSi-n structure strengthened the full interaction between macromolecules MNSi-n and APP, thus forming compact char layers and increasing flame retardancy. It disclosed an effective way to enhance charring flame retardancy by small changes in molecular structure.
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
JOURNAL OF APPLIED POLYMER SCIENCE
·
2024
·Vol. 141
·期 16
·e55270
·
IF 2.7
Yongliang Guo,Haojun Zhang,Jinfeng Cui,Junhong Guo,Baoping Yang
It is of great importance to enhance ability of charring formation for polystyrene (PS) to overcome non-charring feature during burning. Here, we demonstrate a kind of ternary intumescent flame retardant composition composed by a novel ionic liquid butyltriphenylphosphonium-chelated orthoborates (IL) with self-expanded flame retardant, ammonium polyphosphate (APP) and expandable graphite (EG), to improve flame retardancy of PS. This ternary composition promotes limited oxygen index (LOI) value to 26.6 ± 0.5% and UL-94 V0 level for PS composite with 15 wt% total loading. In addition, the peak value of heat release rate and smoke production rate of PS composite with ternary composition are separately reduced by 79.7% and 70.7% comparing to neat PS as well as 44.4% and 29.2% to its IL-free binary counterpart in cone calorimeter test. Meanwhile, the ternary composition displays compact charring bulk constructed by large-expansion-volume vermiform expanded graphite. The TG-FTIR technique is used to analyze gaseous profiles. The rheological property discloses that expansion behavior of the ternary composition contributes to robust viscoelasticity of composite and advantageous network construction at high temperature. Given the fire performance of the ternary composition, the combination of IFR and IL provides an opportunity for rational design and fabrication of functional flame-retardant system.
研究领域:
材料科学
·
火灾安全工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMER BULLETIN
·
2024
·
IF 3.1
Wang Yunfei,Gao Shanjun,Yin Nian,Chen Yuhan,Shen Chunhui,Yu Yi
A new hyperbranched charring-foaming agent (PCAT) containing triazine and triazole groups was successfully synthesized and characterized, and its special pyrolysis behavior was analyzed. It was combined with PAPP as an acid source to form an intumescent flame-retardant system. The composite with 20% flame retardants containing PAPP/PCAT (3:1) showed better flame-retardant and smoke suppression properties. The LOI of the PP/PAPP/PCAT composite increased to 30.2% and achieved UL-94 V-0 rating when the mass ratio of PAPP/PCAT was 3:1. In cone calorimetry experiments, it was demonstrated to reduce PHRR and THR by 84.7% and 48.9%, respectively. Meanwhile, the PSPR and TSP were also reduced by 77.9% and 56.2%, respectively, relative to PP. This indicates that the PP modified by partially doping PCAT in PAPP has significantly enhanced heat dissipation and smoke suppression performance, thus performing higher fire safety. In terms of FRI, PP/PAPP/PCAT composite was considered to be of “good” flame retardancy. Thermal gravimetric analysis demonstrated that PCAT significantly improved the char yield of PP when combined with PAPP. The morphology and properties of the residue showed that PP/PAPP/PCAT could produce a significant expanded foam insulating carbon layer, and the graphitization degree of the residual carbon was enhanced. The investigation of their water resistance demonstrated that the PP/PAPP/PCAT composite still obtained a UL-94 V-0 rating after 168-h soaking in water.
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
RSC Advances
·
2018
·Vol. 8
·期 66
·37631-37642
·
IF 2.936
Haiyang Wu,Rong Hu,Birong Zeng,Li Yang,Ting Chen,Wei Zheng,Xinyu Liu,Weiang Luo,Lizong Dai
In order to develop new phosphorus–nitrogen-containing flame retardants, three novel compounds of DOPO-substituted aminophenyl-s-triazine (TAT-DOPO) with different P/N element ratios were synthesized by Kabachnik–Fields reaction. TAT-triDOPO possessing three DOPO units in one molecule exhibited the best thermal stability. Besides, TAT-triDOPO and TAT-hexaDOPO possessing active hydrogen displayed the characteristics of reactive-type retardant, while TAT-enneaDOPO without active hydrogen represented additive-type retardant. The influences of three TAT-DOPO compounds on the thermal stability, flame retardancy and mechanical properties of the cured EP composites were investigated. Compared with pure EP, the char yields of EP/TAT-DOPO were increased. The LOI value and the UL-94 ratings of EP/TAT-triDOPO with a 5% loading were improved to 34.0% and V-0 grade. The PHRR, THR and HRC of EP/TAT-triDOPO were decreased by 25.7%, 21.1% and 25.4%, respectively. Furthermore, the incorporation of TAT-triDOPO could also improve the flexural strength and elastic modulus of cured EP. It was explained that the existence of active hydrogen atoms within TAT-triDOPO molecule can act as effective chemical cross-linking points in EP network. Finally, based on the SEM and TGA-FTIR analysis of pyrolytic products of cured EP/TAT-DOPO, it was deduced that the prepared TAT-DOPO flame retardant could exhibit both condensed phase and gas phase flame-retardancy mechanism.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
CELLULOSE
·
2021
·Vol. 28
·期 5
·3201-3214
·
IF 5.044
Su Xiaowei,Cheng Chunzu,Zheng Yunbo,Liu Xiaohui,Ren Yuanlin,He Ju,Lin Shenggen,Cheng Bowen
A biomass vitamin B6-based flame retardant, ammonium salt of pyridoxine phosphoric ester acid (ASPPEA) was synthesized and used for modification of lyocell fibers. FTIR, XPS and EDX analyses indicated that lyocell fibers had been successfully grafted with ASPPEA. The ASPPEA improved the char-forming ability, as evidenced by the increase of the char residue (51 wt%) of ASPPEA-treated lyocell fibers. The limiting oxygen index (LOI) value of ASPPEA-treated lyocell fabrics increased up to 48.3%. After 450 min washing, the LOI value remained 30.8%, thus demonstrating the flame retardant durability. The total heat release of ASPPEA-treated lyocell fabrics decreased by 82.5%. During the pyrolysis, the ASPPEA decomposed to produce acidic substances which promoted the dehydration and char formation of lyocell fibers, thus blocked the exchange of heat and flammable gas. This research proposes a novel application of vitamin B6 to impart lyocell fibers with flame retardancy.
研究领域:
材料科学
·
生物质化学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER COMPOSITES
·
2018
·Vol. 40
·期 6
·2244-2257
·
IF 1.943
Lingfeng Xu,Xinwen Tan,Ruijie Xu,Jiayi Xie,Caihong Lei
Molybdenum disulfide (MoS 2 ) with two-dimensional (2D) lamellar structure was functionalized with melamine-cyanuric acid (MCA) hybrids via a facile way. A core-shell composite particle (MoMA) was obtained. Acting as one kind of synergistic flame retardant, it was mixed with traditional intumescent flame retardant (IFR) to prepare the flame retardant poly(lactic acid) composites by melt blending. UL-94 V-0 rating and LOI value of 29.8% for PLA composites were achieved while the total amount of flame retardants was 12 wt%, with the optimal weight ratio of IFR to MoMA 3:1. The inclusion of MoMA can enhance the amount of char residue and suppress the pyrolysis rate. The thermal degradation kinetic studies indicated that more pyrolysis conversion energy was needed. Finally, the investigation of char residue further confirmed that the addition of MoMA can improve the continuity and thermal stability of intumescent char layer and promote its graphitization degree. The condensed phase mechanism was mainly responsible for the improved flame retardant performance. This work suggests a novel strategy for improving flame retardant performance of PLA by combination of MoMA with IFR. The mechanical properties were studied as well. POLYM. COMPOS., 40:2244–2257, 2019. © 2018 Society of Plastics Engineers
研究领域:
材料科学
·
高分子化学
·
燃烧学
✓ 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）