ORGANIC PROCESS RESEARCH & DEVELOPMENT
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2023
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IF 3.4
Shichun Weng,Wei Feng,Wenqian Wu,Zichao Guo,Liping Chen,Wanghua Chen
Nitrophenols and corresponding sodium nitrophenolates are the main side products in the production of mononitrobenzene (MNB). These side products are hazardous due to their thermal instability nature. In this article, the thermal decomposition behaviors of nitrophenols and sodium nitrophenolates were first characterized by differential scanning calorimeter and accelerating rate calorimetry techniques. Then, the influence of phenol and sodium phenolate on the thermal decomposition of MNB was studied to clarify the effect of phenolic hydroxyl groups on the thermal stability of nitrophenols. It was found that compared to nitrophenols, the exothermic peaks of sodium nitrophenolates were more intense and presented strongly autocatalytic features. Sodium phenolate could significantly decrease the decomposition temperature of MNB. Aniline was detected as the unique product in the decomposition processes of pure MNB and MNB/sodium phenolate mixtures, and the nitrosobenzene was verified as the intermediate product. It was experimentally proven that sodium phenolate could catalyze the decomposition of nitrosobenzene (the decomposition intermediate of MNB). The violent decomposition of sodium nitrophenols was caused by the intermolecular catalysis effect of phenoxy groups.
研究领域:
化学工程
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安全科学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2021
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IF 13.273
Donghui Wang,Jiakang Xu,Jinyan Tan,Jinlong Yang,Shuxue Zhou
Amphiphilic coatings, especially those containing zwitterionic groups, are promising as antifouling coatings. Nevertheless, zwitterion based amphiphilic coatings suffer from poor miscibility between hydrophobic and hydrophilic ingredients. Zwitterionic precursors are good candidates to circumvent this issue, but acid or alkaline water must be used in-situ for the zwitterionic group to be self-generated. The in-situ feature restricts its applicability. The objective of this work focuses on developing a new zwitterionic precursor for easy fabrication of zwitterionic groups containing amphiphilic antifouling coatings. This precursor, i.e., triisopropylsilyl 2-methyl-3-((3-(triethoxysilyl)propyl) amino) propanoate (TMAP), was facile synthesized by one step of aza -Michael addition of (3-aminopropyl) triethoxysilane (APS) and triisopropylsilyl methacrylate. Then further blended with hydroxyl-terminated PDMS (HO-PDMS). The curing behavior, morphology, wetting behavior and the antifouling performance both in lab and field were thoroughly examined for coatings with various amounts of TMAP. It was interesting to find that TMAP could not only be hydrolyzed in-situ into a zwitterionic group via a self-catalytic effect during the curing process, but it also efficiently crosslinked the HO-PDMS under ambient conditions. In contrast to APS, TMAP was also more compatible with HO-PDMS and endowed the coating with relatively homogeneous and a smooth surface after prolonged submersion in artificial seawater. The TMAP-based amphiphilic coatings efficiently mitigated the microfouling in both the laboratory assay and the natural field condition in contrast with common silicone elastomer . Notably, excellent resistance for the macrofouler of the mussel was observed for these coatings, especially for 50 wt% TMAP containing coating with zero settlement.
研究领域:
材料科学
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海洋生物学
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表面化学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2022
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IF 16.744
Zizhao Qian,Yuanxiang Xiao,Xujun Zhang,Qing Li,Lujie Wang,Feiya Fu,Hongyan Diao,Xiangdong Liu
Bisphenol A (BPA) is the main precursor in the synthesis of epoxy resins. However, because of its toxic and nonrenewable nature, BPA is unsuitable in the sustainable preparation of epoxy resins. In contrast, Diphenolic acid (DPA) is renewable but its carboxyl group limits its applications in bio-based thermosets. In this study, we report a novel amidation route to tailor DPA to produce epoxide monomers that present epoxy resins with a high performance. The diphenolic amides exhibited very low toxicities when compared with that of BPA, and also provided an unexpected autocatalytic effect on the curing reactions when succinic anhydride (SA) was used as the hardener. Dynamic mechanical analyses (DMA) and tensile test results confirmed the remarkable thermomechanical properties of the cured epoxy resins, which may be attributed to the increased cross-linking density and enhanced hydrogen bonding by the amide groups. Among the SA-cured epoxy resins, diglycidyl ether of diphenolic ethylamide exhibited the best performance, which included a high T g of 114 °C, char yield (CY) of 20%, tensile strength of 60.2 MPa, and toughness value of 185 MPa. In addition, the DPA-derived epoxy resins have great potential in the preparation of bio-based composites because they act as excellent interfaces between the resin and cotton fibers (CoFs). Our study presents a new strategy to prepare bio-based epoxy resins with a high performance, emphasizing the greater potential of amidated DPA derivatives to replace BPA in the epoxy resin market.
研究领域:
材料科学
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化学工程
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可再生资源利用
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产品关联
DOI
高影响因子
ACS Applied Polymer Materials
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2019
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IF 0
Kan Zhang,Xinye Yu,Yuting Wang,Yuqi Liu
Phthalonitrile polymers exhibit many attractive advantages including high thermal and mechanical properties, low water absorptivity, and excellent flame retardancy. However, the poor processability requiring high temperature polymerization for long duration seriously impedes their further applications. In this work, a benzoxazine monomer bearing both norbornene and phthalonitrile functionalities (oHPNI-apn) has been synthesized, and its chemical structure has been confirmed by NMR, FT-IR, and elemental analysis. In addition, the polymerization behavior of oHPNI-apn has been systematically studied using DSC, in situ FT-IR and solid-state 13C NMR analysis. The phthalonitrile in this developed thermosetting system can be thermally induced polymerized at a relatively lower temperature with no added catalysts, which indicates the existence of self-catalyzed effect during the terpolymerization of oHPNI-apn. Moreover, oHPNI-apn-based thermoset is found to possess excellent thermal stability and outstanding flame retardancy, with extremely high Tg temperature (419 °C), very high char yield value (68%, at 800 °C in N2), and extraordinarily low heat release capacity (25.1 J/(g K)) in the absence of any added antiflammable additives.
研究领域:
材料科学
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高分子化学
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产品关联
DOI
ACS Applied Polymer Materials
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2024
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IF 4.4
Shimin Geng,Zhen Huang,Yizhen Chen,Ying Li,Liyuan Zhang,Mingen Fei,Renhui Qiu,Wendi Liu
Polyurethane acrylate (PUA) is a type of photocurable material with high curing efficiency, excellent mechanical properties, and good chemical resistance. However, the synthesis of PUA inevitably involves the use of toxic catalysts, such as dibutyltin dilaurate, which imposes a certain burden on the environment. Meanwhile, strategies to achieve the self-healing ability and reprocessability of PUA have attracted considerable attention. In this study, a palm oil-based fatty acid diethanolamide (POEA) with a tertiary amide structure was used as a diol to synthesize catalyst-free PUA oligomers and provide an autocatalytic effect for the condensation reaction between isocyanates and diols. Furthermore, hydroxyethyl acrylate was selected as a reactive diluent for copolymerizing with PUA oligomers and introducing free hydroxyl groups to promote the dynamic exchange reaction of carbamates. The autocatalytic effects on both the synthesis and the dynamic exchange reaction of carbamates were revealed by model compounds. The resulting networks exhibited satisfactory mechanical properties, excellent scratch repair capability, and recyclability. Moreover, the prepared PUA films showed superior corrosion resistance with an inhibition efficiency of 99.99%, showing great potential applications as coatings for steel. This work provides a feasible technical strategy for the design and synthesis of catalyst-free PUA covalent adaptable networks derived from plant oils.
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 Macromolecular Science Part A-Pure and Applied Chemistry
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2019
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IF 1.163
Jian Hao,Feng An,Chunxiang Lu,Yaodong Liu
New insights for the effects of organic solvent polarities and solvent-monomer interactions on the radical copolymerization for an important copolymer, poly(acrylonitrile-co-methyl acrylate) (PAN-co-MA), were provided in this research. Solvents, dimethylformamide (DMF), dimethylacetamide (DMAc) and dimethyl sulfoxide (DMSO), were used as reaction media. The polarity of these solvents was in the sequence of DMAc < DMF < DMSO. By studying the reactivity ratios of AN and MA, the triad fractions of the resultant copolymers, the interactions between monomers and solvents, and the compositions of copolymers at various conversions, we concluded that the solvent polarity had minimal influence on the copolymerization of AN and MA, while the solvent-monomer interactions played important roles. The interactions between monomer-monomer, monomer-solvent, and solvent-solvent, were calculated based on quantum chemistry methods. Both theoretical calculations and experimental results suggested that AN and MA in DMSO tended to aggregate locally, while they could be homogeneously dissolved in DMAc and DMF. The interactions between solvent and monomers could cause local monomer concentration variations, or ‘bootstrap’ effect, which is one of the critical factors affecting the copolymerization process of AN and MA and the chemical structures of the resultant polymers.
研究领域:
高分子化学
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物理化学
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材料科学
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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）