POLYMER DEGRADATION AND STABILITY
·
2022
·
IF 5.204
Rong Yang,Guozhang Gu,Chen Tang,Zhicheng Miao,Hongwei Cao,Guoxiang Zou,Jinchun Li
It is a great challenge to simultaneously prepare flame-retardant and super-tough poly(lactic acid) (PLA) materials. Herein, we reported a facile approach that PLA reactively blends with phosphorus-containing copolyester. In this paper, a quinary aliphatic copolyester (PPE) containing phosphorus and pendent hydroxyl group was synthesized with sebacic acid, dimethyl malate, diethyl phosphite, 1,6-hexanediol, and 1,3-propanediol by polycondensation. Then, flame-retardant and super-tough PLA materials (PLA/PPEU) can be achieved by reactively blending with PPE and hexamethylene diisocyanate. The results showed that the toughness of PLA was significantly enhanced. The maximum notched impact strength is 75.3 kJ/m 2 indicated a super toughness performance. Meanwhile, the flame retardance of the PLA was improved obviously. The limited oxygen index (LOI) of PLA increased from 20 to 26%. Moreover, the PLA blends can pass the UL-94 V-0 rating. In addition, both the total heat release and total smoke production of PLA were decreased. The resultant super-tough and flame-retardant PLA materials could be widely applied in electrical and electronic equipment.
研究领域:
材料科学
·
聚合物化学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2023
·
IF 8.2
Mohammad Ziaur Rahman,Xin Wang,Lei Song,Yuan Hu
Rising concerns about the toxic effects and environmental issues associated with various fireproof treatments on textiles have led to a demand for “green” materials. Chitosan (CS) is an amino polysaccharide green, recyclable, and non-toxic highly biocompatible biopolymer that consists of multiple hydroxyl groups and has a wide range of applications, including as a flame retardant additive. In this study, an eco-friendly bio-based formaldehyde-free flame retardant containing a higher level of phosphorus and nitrogen in phytic acid ammonia (PAA) was synthesized to amplify the most plentiful green chitosan (CS)-modified polyamide 66 (PA66) fabric surface through a simple pad-dry-cure technique for the improvement of durable flame retardancy with hydrophilicity . The findings revealed that each UV-grafted CS fabric could entirely stop the melt-dripping tendency during the vertical burning (UL-94) test and reached a V -1 rating. Meanwhile, limiting oxygen index (LOI) testing showed a rapid increase from 18.5 % to 24 % for the PA66 control and the PAA-treated (i.e., PA66-g-5CS-PAA) fabric samples, respectively. Moreover, compared to the PA66 control sample, a dramatic decrease in the peak heat release rate (PHRR), fire growth rate (FGR), and total heat release (THR) by approximately over 52 %, 0.63 %, and 19.7 %, respectively, was observed for the PA66-g-5CS-PAA fabric sample. Additionally, this arrangement of PAA catalyzed the charring of grafted CS and acted as a condensed phase flame retardant, resulting in a significant improvement in char yield% in both air and N 2 atmospheres for the PA66-g-5CS-PAA fabric sample in TGA . In addition, only the lower grafting ratio of CS with PAA-treated fabric sample (i.e., PA66-g-2CS-PAA) could encourage it to gain its lowest water contact angle of 0 0 , as well as impersonating a positive effect in improving the flame retardant coating durability in washing and sustaining even after 10 home laundering cycles. This phenomenon suggests that an actual hydrophilic and durable flame retardant finishing procedure for polyamide 66 fabrics might be applied with the novel, plentiful, sustainable, and environmentally friendly bio-based green PAA ingredient.
研究领域:
材料科学
·
纺织工程
·
绿色化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
HIGH PERFORMANCE POLYMERS
·
2017
·
IF 1.179
Xiaoli Wu,Chunlei Dong,Alvianto Wirasaputra,Haohao Huang,Shumei Liu,Jianqing Zhao,Yi Fu
High mechanical properties and flame retardancy of epoxy are important for its applications. A novel star-shaped flame-retardant 5,10-dihydro-phenohphosphazine-10-oxide functioned triazine (TRIDPPA) with high efficiency is synthesized, and its structure is characterized. TRIDPPA is used as the co-curing agent for diglycidyl ether of the bisphenol A/4,4-diaminodiphenyl methane system. The introduction of TRIDPPA greatly improves the flame retardancy of the cured epoxy resins. The epoxy resin (ER)/TRIDDPA1.0 resin acquires a limiting oxygen index value of 30.7% and UL-94 V-0 rating when the mass fraction of TRIDDPA is 1.0 wt% with only 0.086 wt% of phosphorus content. The cross-link density of ER/TRIDDPA1.0 is increased, and the glass transition temperature is improved by 5°C. Besides, tensile strength and toughness of ER/TRIDDPA1.0 are also enhanced.
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
Polymers
·
2022
·Vol. 14
·期 2
·245
·
IF 4.967
Yong Sun,Yongli Peng,Yajiao Zhang
In this work, a flame retardant curing agent (DOPO-MAC) composed of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide DOPO and methyl acrylamide (MAC) was synthesized successfully, and the structure of the compound was characterized by FT-IR and1H-NMR. The non-isothermal kinetics of the epoxy resin/DOPO-MAC system with 1% phosphorus was studied by non-isothermal DSC method. The activation energy of the reaction (Ea), about 46 kJ/mol, was calculated by Kissinger and Ozawa method, indicating that the curing reaction was easy to carry out. The flame retardancy of the epoxy resin system was analyzed by vertical combustion test (UL94) and limiting oxygen index (LOI) test. The results showed that epoxy resin (EP) with 1% phosphorus successfully passed a UL-94 V-0 rating, and the LOI value increased along with the increasing of phosphorus content. It confirmed that DOPO-MAC possessed excellent flame retardance and higher curing reactivity. Moreover, the thermal stability of EP materials was also investigated by TGA. With the DOPO-MAC added, the residual mass of EP materials increased remarkably although the initial decomposition temperature decreased slightly.Keywords:DOPO;flame retardant;curing agent;epoxy resin
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2022
·
IF 7.693
Zhongwei Wang,Shoulu Yang,Zhu Liu,Fangjun Ding,Ning Ji,Yiqiang Wu
A novel method for preparing a tung oil-based flame retardant polyol (MTTO) is described. An epoxidized tung oil methyl ester was initially prepared using green nontoxic phosphotungstate (Ag 3 O 40 PW 12 ·xH 2 O) as the catalyst. The MTTO was then produced from epoxidized transesterified tung oil (ETOME) using diethyl phosphate and ring-opening. The MTTO molecular structure was analyzed using FTIR, 1 H, 31 P, 13 C NMR, and HR-MS. Both MTTO and MTTO-coated melamine-modified bamboo showed excellent flame retardation, with a UL-94 rating of V-0, increased LOI from 28.3 % to 36.4 % and 38.7 %, and significant reductions in the PHRR and THR of the untreated bamboo of 42.7 % and 50.6 % and 37.5 % and 42.1 %, respectively. MTTO was effective in both the gas and condensed phases, preventing bamboo degradation through the release of non-flammable small molecules and the formation of a cross-linked phosphorus-oxygen network carbon layer. Moreover, the addition of melamine led to the release of more non-flammable gases, expansion of the char layer, and increased density of the nitrogen-phosphorus-oxygen cross-linked network carbon layer during combustion, resulting in reduced PHRR and THR.
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 APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 8
·49870
·
IF 2.52
Shengnan Li,Xiaojuan Zhao,Yu Zhang,Xin Yang,Ran Yu,Ying Zhang,Kuilin Deng,Wei Huang
The cage-ladder-structure phosphorus-containing amino-functionalized polyhedral oligomeric silsesquinoxanes (CLNH 2 -POSS) have been synthesized through a facile catalyst-free hydrolytic condensation of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide-vinyltrimethoxysilane (DOPO-VTMS) with 3-aminopropyl trimethoxysilane (KH540). The successful preparation of CLNH 2 -POSS has been proven by the characterization of Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy ( 1 H-NMR, 29 Si-NMR), matrix-assisted laser desorption ionization time of flight (MALDI-TOF), and X-ray diffraction (XRD). Then flame retardant (FR) epoxy resins (EPs) were prepared by the addition of different content of CLNH 2 -POSS into EPs with thermal curing technology. The CLNH 2 -POSS showed good solubility in EP matrix. The well-dispersed CLNH 2 -POSS contributed to thermal, mechanical, and FR properties of EP. Dynamic scanning calorimetry nonisothermal curing scans showed that CLNH 2 -POSS had accelerating effect on the curing of EP. With the addition of only 3 wt% CLNH 2 -POSS (0.30% phosphorus loading), the limiting oxygen index value of the EP composite increased from 25.5 of pure EP to 31.8, and vertical burning (UL-94) V-0 ratings was achieved. In addition, the EP composites showed improved thermal and mechanical properties. The investigations on char residue and pyrolysis volatiles of cured EP further revealed that CLNH 2 -POSS exerted FR effects in condensed and gas phase simultaneously.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2016
·
IF 2.567
Qinqin Luo,Yanchao Yuan,Chunlei Dong,Haohao Huang,Shumei Liu,Jianqing Zhao
The flame retardancy, thermal, and mechanical properties of the cured epoxy resins are difficult to be simultaneously improved. In the present work, a novel DPPA-based curing agent, 10-[(4-hydroxyphenyl)(4-hydroxyphenylimino)methyl]-5,10-dihydrophenophosphazine 10-oxide (H-DPPA), is successfully synthesized to serve as a co-curing agent of 4, 4′-diaminodiphenylmethane (DDM) for bisphenol A diglycidyl ether (DGEBA) epoxy resin. With the aid of 3.0 wt % of H-DPPA, the cured epoxy resin, in which the phosphorus content is as low as 0.22%, passes V-0 rating of UL-94 test with limiting oxygen index (LOI) of 31.8%. The high flame retardancy of epoxy resin modified by H-DPPA originated mainly from the formation of intumescent char layer during combustion. This new type of flame retardant containing both phosphine oxide structure and nitrogen moieties provides epoxy resins with excellent integrated performances.
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
Materials
·
2021
·Vol. 14
·期 9
·2205
·
IF 3.623
Qian Li,Yujie Li,Yifan Chen,Qiang Wu,Siqun Wang
A novel liquid phosphorous-containing flame retardant anhydride (LPFA) with low viscosity was synthesized from 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and methyl tetrahydrophthalic anhydride (MeTHPA) and further cured with bisphenol-A epoxy resin E-51 for the preparation of the flame retardant epoxy resins. Both Fourier transform infrared spectroscopy (FT-IR), mass spectrometry (MS) and nuclear magnetic resonance (NMR) measurements revealed the successful incorporation of DOPO on the molecular chains of MeTHPA through chemical reaction. The oxygen index analysis showed that the LPFA-cured epoxy resin exhibited excellent flame retardant performance, and the corresponding limiting oxygen index (LOI) value could reach 31.2%. The UL-94V-0 rating was achieved for the flame retardant epoxy resin with the phosphorus content of 2.7%. With the addition of LPFA, the impact strength of the cured epoxy resins remained almost unchanged, but the flexural strength gradually increased. Meanwhile, all the epoxy resins showed good thermal stability. The glass transition temperature (Tg) and thermal decomposition temperature (Td) of epoxy resin cured by LPFA decreased slightly compared with that of MeTHPA-cured epoxy resin. Based on such excellent flame retardancy, low viscosity at room temperature and ease of use, LPFA showed potential as an appropriate curing agent in the field of electrical insulation materials.Keywords:flame retardant;phosphorous content;liquid anhydride;epoxy resin
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 16
·11980-11988
·
IF 3.84
Guanghe Song,Xuesong Li,Qiyang Jiang,Jianxin Mu,Zhenhua Jiang
A series of novel structural phosphorus-containing polyimide–polyhedral oligomeric silsesquioxane (POSS) nanocomposites with varying phosphorus contents were synthesized. The nanocomposites displayed outstanding thermal properties. The glass transition temperature was increased to 294.87 °C when the phosphorus content was 1.61 wt% and the anti-degradation properties were also obviously enhanced. Moreover, the nanocomposites presented much higher atomic oxygen (AO) durability compared with pure polyimide because of the incorporation of special functional groups of phosphorus oxide and POSS. The AO erosion yields decreased to 51.9% of pure polyimide–POSS nanocomposites when the phosphorus content was increased to 1.61 wt%. Furthermore, the mechanism of phosphorus and POSS synergistic AO resistance was explored via XPS and SEM. Three kinds of silicon particles with different binding energies and two kinds of phosphorus elements with different binding energies were formed because of AO exposure and the phosphorus and POSS synergy. Highly effective self-passivating layers were formed to protect the underlying material from AO attack.
研究领域:
材料科学
·
航天工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2022
·
IF 5.204
Jianfan Cao,Huajun Duan,Jiahao Zou,Junjun Zhang,Chao Wan,Chenhao Zhang,Huiru Ma
Endowing anhydride-cured epoxy resin (EP) with excellent flame retardancy while maintaining good comprehensive properties has become a great challenge. In this context, a bio-based phosphorus-containing benzoxazine monomer (SFD-BOZ) composed of DOPO, furfurylamine, salicylaldehyde and paraformaldehyde was successfully synthesized via a two-step reaction, and then blended into EP/methyltetrahydrophthalic anhydride (MeTHPA) system. Though SFD-BOZ exhibited no significant effect on the curing activity of EP/MeTHPA system, the introduction of SFD-BOZ made FREP show better heat resistance. Besides, the flame retardancy of EP was markedly improved due to the incorporation of SFD-BOZ. The modified EP with 20.7 wt% SFD-BOZ achieved V-0 rating of UL-94 and obtained limited oxygen index (LOI) value of 35.2%, which was 76% higher EP. Also, its peak heat release rate (PHRR), total heat release (THR) and total smoke production (TSP) dramatically declined by 53%, 36% and 45% as compared to that of EP, respectively. Furthermore, the flexural and tensile strengths of modified EP showed the maximum increments of 9% and 49%, respectively. The incorporation of SFD-BOZ manifested the potential for developing high-performance epoxy resin.
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
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
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2023
·
IF 8.2
Jing He,Tao Yu,Yan Li
With the growing environmental awareness, poly(lactic acid) (PLA) is regarded as one of the most promising varieties of bio-based polyesters owing to its environment-friendly and biodegradable advantages. However, poor thermal stability and flammability disadvantages limit the applications of PLA. Herein, a series of biodegradable intrinsic flame-retardant thermoset PLA resins (DMMP-M4sPLA) were designed. DMMP-M4sPLA resins exhibit excellent flame retardancy, achieving UL 94 V-0 rating and limiting oxygen index (LOI) of 28.1 %–31.7 %. Meanwhile, the cured DMMP-M4sPLA resins show a high glass transition temperature and tensile strength . In addition, the resins demonstrate full degradation with no harmful degradation products. This work provides an advanced design strategy to create bio-based and biodegraded resins with superior flame retardant and mechanical performance, holding great potentials in the fields of aviation interior, automotive, etc.
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
危险品化学品经营许可证（带存储）