ACS Applied Polymer Materials
·
2023
·
IF 5
Xiaoqing Qiu,Zhiwei Li,Venkata Chevali,Pingan Song,Xiaohong Li,Zhijun Zhang
Unsaturated polyester (UP) has many important industrial applications, including transportation, building materials, and electrical insulation. However, UP resins are extremely flammable, thus restricting their real-world applications. Herein, we report a mesoporous silica-based ternary flame retardant (NF@SiO2-D) for UP by loading nickel ferrite and dimethyl methylphosphonate (DMMP) via hierarchical assembly. NF@SiO2-D acts as a fire extinguisher of UP through the combined effect of mesoporous silica, nickel ferrite, and DMMP. The peak and total heat release rates of the UP matrix decreased by 36.3% and 36.9%, respectively, after the incorporation of 10 phr NF@SiO2-D. More importantly, when NF nanoparticles were present, the smoke production of the UP matrix was reduced by 41.5% compared to the control samples without NF nanoparticles. In addition, 20 phr of NF@SiO2-D enabled the UP to achieve a self-extinguishing ability and a desired V-0 grade in the UL 94 test. The flame-retarding UP composites with NF nanoparticles also exhibited better thermal stability and Tg than the control samples. The resultant fire-retardant UP composites are anticipated to find more industrial applications.
研究领域:
材料科学
·
化学工程
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DOI
高影响因子
CHEMOSPHERE
·
2023
·
IF 8.8
Fukai Chu,Wei Wang,Yifan Zhou,Zhoumei Xu,Bin Zou,Xin Jiang,Yandong Hu,Weizhao Hu
Unsaturated polyester resins (UPR) are composed of prepolymers and styrene diluents, while the former are produced by co-polycondensation between diol, unsaturated diacid and saturated diacid. In this work, bio-based UPR prepolymers were synthesized from bio-based oxalic acid , itaconic acid, and ethylene glycol, which were then diluted with bio-based isosorbide methacrylate (MI). Meanwhile, the phenylphosphonate were introduced into the molecular chains of prepolymers to achieve intrinsic flame retardancy of bio-based UPR. The potential of the reactive MI diluents as substitutes of volatile styrene, was also assessed through the volatility test, curing kinetics and gel contents analysis. For UPR materials with styrene diluents, the UPR materials can achieve UL-94 V 0 level and the 28% of limiting oxygen index (LOI) with 2.63 wt% of phosphorus contents. By contrast, the UPR materials with MI diluents can reach UL-94 V 0 level with only 2.14 wt% of phosphorus contents. As the phosphorus contents were further increased to 2.63 wt%, UPR materials can achieve highest 29%, while the peak of heat release rate (PHRR) and total heat release (THR) were decreased by 68.01% and 48.62%, respectively. The Flame Retardancy Index (FRI) was also used to comprehensively evaluate the flame retardant performance of UPR composites. Compared with neat UPR, the composites with MI diluents and phosphorus containing structures increased from 1.00 to 6.46. The mechanism for improved flame retardancy was analyzed from gaseous and condensed phase. Additionally, the tensile strengths of bio-based UPR materials with styrene and MI diluents were studied. This work provides an effective method to prepared high-performance and fully bio-based UPR materials with improved flame retardant properties and safety application of reactive diluents.
研究领域:
材料科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2015
·Vol. 132
·期 47
·
IF 1.768
Yi-Fan Zhang,Xiao-Jun Wang,Zhi-Gang Pan,Cheng-Ming Hong,Gao-Feng Ji
The activation of foaming agent is critical to its application. In this study, 4,4′-oxibis-(benzenesulfonyl hydrazide) (OBSH) activated by urea was used in the manufacture of low-density unsaturated polyester resin (LDUPR), and the results were compared with that of OBSH activated by zinc oxide and zinc stearate. The experiment results showed that the activation of OBSH by urea was better than by zinc oxide or by zinc stearate. A novel hydrogen bond activation mechanism of urea is presented in this research. Two stages, including the induction stage and the foaming stage, were proposed in the LDUPR manufacture according to the gas evolution curves of activated OBSH. The decomposition temperature and the decomposition time of OBSH activated by urea were determined to match the gelation time of UPR for the manufacture of LDUPR. The disadvantageous chemical behaviors of activated OBSH were eliminated in the induction treatment. The activated OBSH via induction treatment released gas maximally and distributed gas homogeneously in the resin glue, resulting in a better foaming effect than that of the previous foaming agents. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132 , 42824.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
POLYMER
·
2026
·
IF 4.5
Menglin Wu,Meng Jia,Bo Xu,Lijie Qu,Yuhao Li,Lei Yang,Lijun Qian
Conventional thermosets are difficult to reprocess, recycle and reshape due to their permanent covalent cross-linking, and their flammability limits a wide range of applications. Herein a novel thermally switchable polymer, capable of transitioning from a thermo-reversibly self-healing polymer (re-PO-co-UPR) into an irreversibly cross-linked polymer (i-PO-co-UPR) with higher flame-retardancy, has been built through forming covalent adaptable networks (CANs) by Diels-Alder (DA) reaction between the unsaturated double bonds of polyester (UPR) and furan groups of the synthesized flame retardant cross-linker (POFA). Re-PO-co-UPR presents excellent self-healing properties and reprocess-ability owing to DA/rDA reactions which proceeds in the melt, with no need for any solvent, catalyst or additive. At higher temperatures, irreversible alkene addition reactions of UPR are triggered, forming irreversibly cross-linked conventional thermosets i-PO-co-UPR, which shows outstanding flame retardancy with 29.6% limiting oxygen index (LOI) and UL-94 V-0 rating. Such a convenient preparation and flexible structure design of CANs has successfully broken the boundary between thermoplastic and thermoset materials, so that they acquired self-healing properties and can be recycled through de-crosslinking process after being discarded. A prime example for the development of renewable thermoset materials has been presented.
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DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2019
·
IF 5.155
Nidhin Divakaran,Xu Zhang,Manoj B. Kale,T. Senthil,Suhail Mubarak,Duraisami Dhamodharan,Lixin Wu,Jianlei Wang
The constant urge to boost the versatility of unsaturated polyester (UP) in the burgeoning area of automotive and aircraft industries has shifted the focus on developing high performance UP based nanocomposites with remarkable thermal, mechanical, and electrical properties. The current work traverses through the innovative method to contrive functionalized graphene oxide (f-GO)/UP nanocomposites. Graphene oxide, synthesized from graphite using modified Hummers’ method, manifests into f-GO (GO-MAH and GO-NH 2 ) via surface chemical functionalization. Different loadings of f-GO were assimilated within UP matrix through in-situ polymerization. The comprehensive properties of the nanocomposites enhance, despite addition of f-GO as low as 0.04 wt%, which itself gives a scrupulous vindication of proper dispersion of fillers and formation of exfoliated and intercalated nanostructures, with SEM images furnishing the inference of meticulous dispersion. The fabricated nanocomposites exhibit tensile strength augmentation by 75.2% for ultralow content of 0.08 wt% f-GO. Furthermore, the 0.10 wt% addition of f-GO within UP displays 53.8% increase in storage modulus and thermal decomposition temperature at 10% mass loss boosts by 70.3 °C, while the electrical conductivity surges by 10 9 S/m. The surface functionalized graphene oxide and their interaction with UP played a vital role in their property enhancement.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
WOOD SCIENCE AND TECHNOLOGY
·
2014
·Vol. 48
·期 6
·1241-1255
·
IF 1.873
Liu Wendi,Chen Tingting,Wen Xiaoyun,Qiu Renhui,Zhang Xincong
Bamboo fibers were mechanically extracted from raw green bamboos by crushing, rolling, and combing techniques with 1,4-butanediol as a solvent. The morphology of the bamboo fibers thus obtained was analyzed. The bamboo fibers were treated with isocyanatoethyl methacrylate (IEM) in the presence of dibutyltin dilaurate as a catalyst, to improve the interfacial adhesion between the fibers and unsaturated polyester (UPE) resins. The bamboo fibers reinforced UPE composites were prepared by hand lay-up compression molding. FTIR, XPS, and NMR analyses indicated that the IEM was covalently bonded onto the bamboo fibers via carbamate linkages. The IEM treatments significantly increased the tensile strength, flexural strength, flexural modulus, and water resistance of the resulting composites and yet decreased the impact strength of the composites. The SEM images of the tensile-fractured surfaces of the IEM-treated bamboo fibers–UPE composites revealed that the fiber treatments markedly improved the interfacial adhesion between the bamboo fibers and UPE resins.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2017
·
IF 2.843
Xiaojuan Yu,Ying Pan,Dong Wang,Bihe Yuan,Lei Song,Yuan Hu
Ramie fabrics were modified with biobased electrolytes, i.e. cationic chitosan and anionic phytic acid, and the flame retardant cationic electrolyte melamine by a layer-by-layer (LbL) assembly method. Then, the LbL-modified fabric-reinforced unsaturated polyester resin (UPR) composites were fabricated by a hand lay-up method. The onset thermal degradation temperature of the LbL-modified fabric-reinforced UPR composites was lower than that of the raw fabric-reinforced UPR sample, while char residues of the composites were greatly improved and the release of combustible organic volatiles was suppressed during the combustion. Moreover, the flame retardancy of the composites was enhanced with increasing the LbL assembly number, which was evidenced by the markedly reduced peak heat release rate and the total heat release values obtained from cone calorimetric tests. The limiting oxygen index value of the composites was increased from 26.0% to 34.5%.
研究领域:
材料科学
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纺织工程
·
高分子化学
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产品关联
DOI
高影响因子
MACROMOLECULAR MATERIALS AND ENGINEERING
·
2022
·Vol. 307
·期 9
·2200203
·
IF 4.402
Yong Li,Jiehao Qu,Zenghui Dai,Junyi Jiang,Jiajia Fu,Feiya Fu,Xiangdong Liu
Herein, the successful design of a highly bio-based family of unsaturated polyester resins (UPRs) is presented, comprising of an isosorbide (ISO) incorporated unsaturated polyester prepolymer (UP) and a reactive diluent of 4-vinylguaiacol acetyl ester (ACVG). A series of UPs are prepared by copolymerizing ISO with other green monomers, i.e., itaconic acid, ethylene glycol and oxalic acid, in a variation of ISO fraction. The UP/ACVG mixtures exhibit very low viscosity ranging from 2.8 to 3.7 Pa s. After curing at 135 °C to form a network, the resulting thermosets exhibit remarkable improvements in terms of glass transition ( T g , about 131 °C), storage modulus (2564–3342 MPa), and tensile strength (around 76.6 MPa), which are significantly better than the UP thermosets reported in previous works, The incorporation of ISO units into the UPs reveals a favorable effect on thermal stability of the thermosets as well. The best Td5% is measured to be 320.4 °C, and the volatile molecular information collected using a TGA-GC/MS set suggests that the decomposition mechanism of the cross-linked resins becomes heat-resistant due to the ISO incorporation. Moreover, after being reinforced by cotton fabrics, an outstanding compatibility between the ISO containing UPRs and cotton fibers is found to be suitable for composite fabrication.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
Journal of Cleaner Production
·
2021
·
IF 9.297
Ning Zhang,Xianglin Hou,Xiaojing Cui,Lin Chai,Hongyan Li,Hui Zhang,Yingxiong Wang,Tiansheng Deng
Plastic waste is increasingly aggravating environmental pollution problems. Unsaturated polyester resin is one kind of thermoset resins . Its three-dimensional network endows it good mechanical and chemical properties, but made its degradation and recovery challenging. Here we report a novel and efficient reaction system consisting of amphiphilic p-toluenesulfonic acid/acetic acid aqueous solution for decomposition of unsaturated polyester resin by acyl exchange reaction. Amphiphilic p-toluenesulfonic acid facilitated the entrance of itself and solvent into the resin and consequently promoted catalytic cleavage of ester bonds in unsaturated polyester resin. Water, as a co-catalyst, stabilized the key reaction intermediate species, which reduced largely the overall reaction activation energy and thus accelerated the degradation of the resins. Unsaturated polyester resin was completely degraded and converted to the valuable chemicals at 180 °C, which can be then recycled by a new separation process. The degradation products were mainly ethylene glycol diacetate, phthalic acid, and copolymer products of styrene and maleic anhydride, with the mass ratio of 43.18%, 24.81% and 44.16% to raw unsaturated polyester resin waste, respectively. The atoms of unsaturated polyester resin were completely incorporated into the high-value degradation products with zero production of waste. Hence, this work provides a green, economical, practical strategy to degrade waste unsaturated polyester resin and recycle high-value chemicals with an 100% atom utilization efficiency.
研究领域:
环境科学
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化学工程
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材料科学
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可持续化学
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产品关联
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2023
·
IF 6.6
Jianzhong Zhang,Yang Fang,Anlin Zhang,Youming Yu,Lina Liu,Siqi Huo,Xuesen Zeng,Hong Peng,Pingan Song
Despite extensive applications in modern industry, unsaturated polyester resin (UPR) suffers intrinsic flammability, presenting fire threats to both environment and properties. Existing environmentally benign flame retardants, in particular ammonium polyphosphate (APP), often show a limited efficiency in UPR. Herein, a Schiff base-coated ammonium polyphosphate (MAPP) was synthesized using APP, 1,2-bis(2-aminoethoxy)ethane, and terephthalaldehyde (TPA). The results show that MAPP retards the initial decomposition of UPR and promotes its carbonization under heating, imparting enhanced thermal stability. Notably, 17 wt% of MAPP endows UPR with a UL-94 V-0 rating and a limiting oxygen index (LOI) of 28.6 %. MAPP is also effective in inhibiting heat and smoke release during combustion, and 17 wt% of it brings about 39.5 % and 18.0 % reductions in total heat release and total smoke production. Because of improved interfacial compatibility, the final UPR/MAPP displays significantly improved mechanical properties relative to UPR/APP. This work proposes a new functionalization surface modification strategy for creating efficient APP-based flame retardant for UPR, which is expected to be more widely applied in industries.
研究领域:
材料科学
·
化学工程
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产品关联
DOI
高影响因子
ACS Omega
·
2024
·
IF 3.7
Tianle Xu,Xinran Ju,Hui Tang,Wenli Xiang
Fir wood was modified using epoxy soybean oil, diethylene glycol, and maleic anhydride as raw materials to enhance its mechanical properties, thermal stability, and water resistance. Diethylene glycol first opens the epoxy ring of the soybean oil and then reacts with maleic anhydride to produce an esterification reaction. The product modifies the fir wood through a chemical impregnation method. A systematic evaluation of the modified wood’s weight gain ratio, density, mechanical properties, thermal stability, water resistance, and microstructural changes was conducted. The results show that the compressive strength increased from 38.1 to 94.9 MPa, the water absorption rate decreased from 158.03 to 6.93%, and the thermal stability was also enhanced. This study provides a simple, low-cost, and green method for improving the comprehensive performance of fast-growing fir wood, offering new insights for achieving sustainable development and green chemical engineering.
研究领域:
木材科学
·
绿色化学
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产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2013
·Vol. 3
·期 44
·22380-22388
·
IF 2.562
Chengguo Liu,Zhimin Wang,Yu'an Huang,Hongfeng Xie,Zengshe Liu,Ying Chen,Wen Lei,Lihong Hu,Yonghong Zhou,Rongshi Cheng
This paper reports a convenient one-pot method integrating a novel solvent-exchange method into in situ melt polycondensation to fabricate unsaturated polyester nanocomposites containing functionalized graphene sheets (FGS). A novel solvent-exchange method was first developed to prepare graphene oxide/ethylene glycol (GO/EG) dispersions in a reactor equipped with a fractionating device. The prepared dispersions were applied successively to fabricate unsaturated polyester composites via in situ melt polycondensation in the same reactor. The dispersion behavior of GO/EG dispersions was characterized by atomic force microscopy (AFM). The structures and properties of the as-prepared FGS/polyester nanocomposites were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), tensile tests, thermogravimetric analysis, and dynamic mechanical analysis. The results of AFM show that GO nanosheets are well exfoliated in EG solvent. The results of FT-IR, XRD, Raman, SEM, and TEM indicate that the FGS are also finely exfoliated in the polyester matrix and have strong interaction with the host polymer. Compared with the neat UPR matrix, the composite with an extremely low content of 0.08 wt% FGS exhibits maximum increases of 53.6% and 48.4% in tensile strength and modulus; the composite with 0.32 wt% FGS has a 10.7 °C increase in thermal decomposition temperature and a 17.9 °C increase in glass transition temperature. Therefore, building on this work to generate unsaturated polyester nanocomposites with improved properties at reduced cost is possible.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）