PROGRESS IN ORGANIC COATINGS
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2023
·
IF 6.6
Jiexiang Tong,Subin Xie,Jia-Tao Miao,Jing Luo,Ren Liu
Polyurethane-urea acrylate (PUUA) has been used to develop mechanically robust materials, due to the urea-based bifurcated H-bond. However, the uncontrollable reaction rate between diamine and diisocyanate makes it difficult to prepare PUUA. Herein, we put forward a simple method to synthesize PUUA, which was then used to prepare UV-cured PUUA coatings with simultaneous high hardness and excellent toughness. In our strategy, a novel diol containing urea group has been designed, which was employed as chain extender to synthesize PUUA at a controllable polymerization rate. By adopting chain extenders with different molecular structures, two kinds of PUUA were synthesized. The molecular structures of diol containing urea group and PUUA were identified by Fourier transform infrared spectroscopy (FTIR) and Nuclear magnetic resonance spectroscopy ( 1 H NMR). Benefiting from the strong urea-based H-bond, the UV-cured PUUA films showed simultaneously enhanced mechanical strength and toughness. Specially, the optimal PUUA film exhibited high mechanical strength (19 MPa), high elongation at break (310 %), and high toughness (26.9 MJ m −3 ), which was 9.5, 2.8 and 19.2-fold increase compared with polyurethane acrylate (PUA) film without urea groups. Correspondingly, the UV-cured PUUA coatings exhibited higher impact resistance and higher hardness than PUA coating. This work provides a new avenue to develop PUUA for high-performance UV-curable coatings.
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 Materials Chemistry C
·
2023
·Vol. 11
·期 36
·12261-12269
·
IF 6.4
Ying-Jie Ma,Jing-Wen Wang,Guo-Chao Zhuang,Yang Zhang,Zi-Long Zhang,Ming-Yue Zhang,Guang-Bin Ji
To overcome the effect of high actuation voltages causing dielectric elastomer films to breakdown, fabricating films with excellent dielectric properties and high durability is the current focus. Previously reported dielectric elastomer films, nevertheless, still require better dielectric properties and suffer from a lack of self-healing properties, which reduces the service life of the films. In this work, polysulfide polyurethane–urea (PSPU) elastomers with self-healing properties were synthesized through the insertion of dynamic disulfide bonds into the polymer chain segments via hydrogen transfer reactions. In addition, PSPU-based composites were fabricated in which the filler was MXene loaded with CeO2 obtained using a hydrothermal method. Benefiting from dynamic disulfide bonding and multiple hydrogen bonding interactions, PSPU attained a self-healing efficiency of 95%. Moreover, the 5.25 vol% CeO2@MXene/PSPU composite exhibited a dielectric constant of 206 at 100 Hz, maintaining a loss of 0.19 while having a self-healing efficiency of 97.9%. In contrast to PSPU, the dielectric constant of 5.25 vol% CeO2@MXene/PSPU was 34 times higher than that of the former at 100 Hz. These distinctive properties promise to render the films an integral part of the actuator.
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
高影响因子
OPTICAL MATERIALS
·
2023
·
IF 3.9
Xinhai Lv,Hongye Yan,Zhenbang Wang,Jianrong Dong,Chang Liu,Yu Zhou,Hongxiang Chen
Photo-responsive polymers, obtained by incorporation of photochromic azobenzene groups into polymer, can display reversible photoactuation behavior. However, the damage can cause a reduction in their service scope or service lifetime. It remains a challenge to design healable and reprocessable azobenzene-containing polymers. The polyaddition of isophorone diisocyanate (IPDI) with p -diaminoazobenzene (DAAB) and amino-terminated poly(propylene glycol) (D2000) was performed to prepare the main-chain polyurea elastomer . The hydrogen bonding between urea groups can enhance self-healing of polyurea elastomer, but its influence on photo-responsive behavior of polyurea elastomer is not clear. The proportion of ordered hydrogen bonds was regulated by changing azobenzene content and the ratio of hard/soft segments. The ordered hydrogen bonds played a fundamental role in the maximum peak intensity of polyurea, while they had no direct effect on the photo-responsive efficiency of polyurea. This study provides a feasible way to obtain healable and reprocessable azobenzene-containing polymers.
研究领域:
材料科学
·
化学
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DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2023
·
IF 6.6
Biru Shi,Yinglu Sun,Xinxin Tian,Jiahui Zhong,Zhenyu Zhang,Xiangdong Liu,Dekun Sheng,Yuming Yang,Wenhua Zhang
Adhesives are widely used to bond various materials and surfaces, hot melt adhesives (HMAs) have conquered almost every industry area due to their solvent-free volatilization and ease of use. However, preparing reusable HMAs with high shear strength is still extremely challenging. Here, we show a simple way to prepare a reusable HMA, OPU (oxime-based polyurethane), with high lap shear strength based on oxime-urethane bonds. Cu(II) ions were introduced to further enhance the bulk strength to form ligand bonds. The relationship between the ligand bond content and the material properties was also investigated. Increasing ligand bond content limited the degree of crystallinity and shear strength. And the breaking stress and toughness of the coordinated material were significantly increased. The initial shear strengths of OPU for 304 stainless steel (after this referred to as “steel”) and aluminum reached 12.6 MPa and 9.3 MPa, respectively, which is the highest shear strength available for oxime-urethane-based polyurethane HMAs. After 10 repetitions, the OPU still retains its high shear performance. By analyzing the relationship between shear strength and the amount of Cu(II), it is found that the shear strength is strongly related to chain mobility and Young's modulus . This work demonstrates a useful way of synthesizing reusable HMAs with high lap shear strength.
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 ELECTROANALYTICAL CHEMISTRY
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2023
·
IF 4.5
Haifeng Yao,Yahui Zhang,Yongping Dong,Mingfu Ye
Graphdiyne (GDY) is considered as another promising carbon material in biosensing field. However, the application of GDY in ECL sensing is in its infancy stage, and different roles of GDY are urgent to be discovered. In this work, strong anodic Ru(bpy) 3 2+ electrochemiluminescence (ECL) was obtained at a cucurbit[8]uril (Q[8]) modified electrode. Although GDY exhibited electrocatalytic effect on the oxidation of Ru(bpy) 3 2+ , an apparent inhibiting effect of GDY on the ECL signal was observed due to the energy transfer. An “on-off-on” mode ECL sensor was fabricated to detect pancuronium (PMD) based on the competitive host–guest interaction between ferrocene (Fc), PMD and Q[8]. Fc modified single-stranded DNA was immobilized onto the surface of GDY, which could be attached onto the electrode through the interaction between Fc and Q[8]. The quenching effect of GDY could apparently decrease ECL signal. PMD exhibited stronger combining ability with Q[8] than Fc, and could replace Fc from the cavity of Q[8], leading to the recovery of ECL signal. The variation of ECL intensity changed linearly with the PMD concentration in the range of 10 nM to 50 μM with a detection limit of 5 nM (3σ). The proposed sensor has high sensitivity, outstanding specificity and accuracy, indicating that GDY has promising potential application in ECL sensing field based on its inhibiting effect.
研究领域:
分析化学
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生物传感
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材料科学
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产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2024
·
IF 5.7
Yonghao Zhang,Yan Guo,Yang Liu,Zhongqi Shi,Wenfeng Liu,Jinzhan Su,Guohua Chen,Di Zhou
All-organic dielectric materials require high performance in applications such as transportation, microelectronics, and aerospace power systems. In this work, aromatic polythiourea (ArPTU) was synthesized via a one-step method. A series of polymer composite films were prepared using ArPTU and polyetherimide (PEI) as raw materials. The experimental results showed that the composite films have better dielectric properties than the pure PEI films. Taking the blend membrane with an ArPTU mass fraction of 2% as an example, the composite films have good dielectric properties (εr = 3.58, tan δ = 0.007), high energy density (5.34 J cm−3 at an Eb = 580 MV m−1), and a charge–discharge efficiency of 85% at 150 °C. At 25 °C, the maximum Ue was 5.75 J cm−3, and the efficiency could be maintained above 97%. It was speculated that the strong polarity of ArPTU and good compatibility with PEI were the reasons for its performance improvement. The ArPTU/PEI composite films demonstrated excellent comprehensive performances, combining the advantages of both ArPTU and PEI and have potential in a wide range of applications in the field of high-temperature media.
研究领域:
材料科学
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电气工程
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产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2024
·
IF 8.4
Chenchen Zhang,Si Chen,Yi Zhao,Jianqiang Meng
Polybenzimidazole (PBI) has garnered significant interest in desalination due to its exceptional chemical stability and mechanical strength , but suffers from poor water permeability. In this work, different contents of hydroxylated Cucurbit [6]uril (CB [6] were added to PBI to build a “water transport channel”. The effects of CB [6] addition on the chemical structure and surface morphology were analyzed by FTIR, SEM, and Zeta potential , respectively. Based on the solution-diffusion model, the effect of CB [6] on the water/salt transport properties of PBI membranes was thoroughly investigated. The results show that appropriate CB [6] doping can enhance water sorption of PBI through the special “outer hydrophilic and inner hydrophobic cavity” structure, and boost water diffusion with the channeling effect of the hydrophobic CB [6] cavity. While the complexation between the carbonyl group in CB [6] and Na + ions slightly increased salt sorption, the specific cavity structure of CB [6] can significantly decrease salt diffusion by blocking salt ions and increasing transport path tortuosity. The cavity effect of CB [6] was further confirmed by hybridizing CB [6] with biphenylsulfonyl-substituted PBI when the cavity can be occupied. Therefore, the introduction of CB [6] improves the water/salt diffusion selectivity and then the permeability selectivity of PBI. Notably, the PBI@CB [6] membrane with a 0.25 wt% CB [6] loading exhibited a 40-fold increase in water permeability coefficient compared to pure PBI, while experiencing only a slight decrease in salt permeability coefficient, water/salt selectivity almost exceeding the empirical upper bound line of polymers. This work provides a theoretical foundation for the development of high-performance desalination membranes based on macrocyclic molecules such as CB [6].
研究领域:
材料科学
·
环境工程
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产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2024
·
IF 3.8
Liqian Zhu,Liang Zhu,Jijiang Hu,Zhen Yao,Zhiyang Bu,Suyun Jie,Bo-Geng Li
Polyurea elastomers with excellent mechanical properties are widely used in a variety of applications due to the unique microphase separation structure and high flexibility in formulations. A key point in the development of polyurea elastomers is to explore the structure–property relationship. However, few studies have focused on the effect of soft segment structures because of the limitation that the flexible soft segments are usually commercialized amine-terminated polyether. Herein, a series of polybutadiene-based polyurea elastomers were prepared to systematically investigate the influence of the network structures on the ultimate properties of the polyurea materials. In particular, the amine-terminated liquid polybutadiene rubber with tunable molecular weights and liquid polystyrene–butadiene rubber were synthesized via the degradation method for flexible regulation of the soft segment structure. The results demonstrated that performance optimization could be achieved by manipulating the degree of hydrogen bonding, which was controlled by the network structure. Besides, the polybutadiene-based polyurea elastomers exhibited excellent low-temperature properties, owing to the high cis-1,4 content.
研究领域:
材料科学
·
高分子化学
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产品关联
DOI
高影响因子
ACS Applied Polymer Materials
·
2024
·
IF 4.4
Shan Jiang,Li Liu
Poly(hydroxyurethane)s (PHUs) are regarded as one of the most promising nonisocyanate-based polyurethanes, with their improved performance attracting widespread attention. As a type of PHU, poly(hydroxyurethane-urea)s (PHUUs) can effectively broaden the performance range of PHUs, demonstrating high potential for various applications. In this study, cross-linked PHUU elastomers were prepared through aminolysis of cyclic carbonate, using carbon dioxide-based tricyclic carbonate of glycerol (GTC) as the cross-linker, and carbon dioxide-based amino-terminal polyurea oligomer (TTD*/HMDA*) as the chain extender. The cross-linking density and thermal and mechanical properties of the PHUU elastomers could be tailored by controlling the feed ratio of GTC or TTD*/HMDA*. The reprocessability of the PHUUs was also investigated. To further optimize the properties of PHUUs, modified PHUUs with improved cross-linking density were prepared utilizing pendant hydroxyl groups as cross-linking points. Methacrylic acid (MA) was grafted onto the hydroxyl group, and simultaneously, a dense cross-linking network of the modified PHUUs was formed through the polymerization of MA. With the introduction of MA, modified PHUUs showed an increased glass transition temperature and adjustable mechanical properties. The tensile strength, Young’s modulus, and elongation at break of modified PHUUs were in the ranges of 1.19–15.00 MPa, 0.69–95.65 MPa, and 138–687%, respectively. Modified PHUUs exhibited significantly improved tensile strength and Young’s modulus than those of PHUUs. This work provides an option for preparing high-performance or functionalized PHUUs.
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
·
2024
·
IF 4.1
Hongyang Deng,Lixian Guo,Keping Chen,Ping Zhang,Yewei Xu,Ningning Song,Chunrong Tian,Jianhua Wang,Shuen Liang
Polyurea (PUA) elastomers have gained increasing attention in both defense and civilian fields due to its remarkable mechanical properties and protective capabilities. However, its high flammability significantly limits its application in many fields. It is challenging to achieve high flame retardant rating and maintain high mechanical properties simultaneously. Synergistic combination of different types of flame retardants is essential for this purpose. Herein we report a highly efficient synergistic combination of 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (BTDA) and ammonium phosphate (APP) for flame retardance of PUA. BTDA contributes to excellent char-forming in solid phase, and APP contributes to radical scavenging in gaseous phase. By incorporating BTDA and APP as additive flame retardants in PUA, the melt dripping in combustion was entirely suppressed, and V-0 rating in UL-94 test was achieved. The heat release rate and the release of smoke and toxic gases were greatly reduced. Meanwhile, the mechanical properties of PUA were maintained very well. The PUA composites with outstanding flame retardancy and mechanical properties may serve as ideal protective materials in a variety of applications.
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
MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2016
·Vol. 217
·期 16
·1851-1859
·
IF 2.495
Rui Qi,Yong Jin,Xinfeng Cheng,Hanping Li,Shuangquan Lai,Xiaopeng Sun
Herein, a novel coil-rod-coil triblock copolymer with the coil blocks composed of poly(ethylene glycol) methyl ether and the rigid midterm block alternatively connected with isophorone diisocyanate and isophorone diamine is developed. The triblock copolymer can self-assemble into ellipsoidal micelles in 1-methyl-2-pyrrolidinone. After the addition of a second coil-selective solvent (water) to the micellar solutions, these ellipsoidal micelles can further transform into chain-like nanostructures. The self-assembly behavior is highly influenced by the additional order of the solvents, which is considerably due to the impacts of the hydrogen-bonding urea groups and rigid motifs. The transition of the ellipsoidal micelles to chain-like nanostructures is governed by the water molar fractions. The sizes of the chain-like nanostructures increase first and then decrease with the growth of the water molar fractions in the mixed solutions.
研究领域:
材料科学
·
化学
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DOI
高影响因子
Coatings
·
2021
·Vol. 11
·期 2
·251
·
IF 2.881
Jijia Zhang,Jihu Wang,Shaoguo Wen,Siwei Li,Yabo Chen,Jing Wang,Yan Wang,Changrui Wang,Xiangyi Yu,Yan Mao
In this paper, an environmentally friendly waterborne polyurea (WPUA) emulsion and its corresponding coating were prepared, which was characterized by dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), and scanning electron microscopy (SEM). To improve the performance of the coating, we doped sulfonated graphene (SG) into WPUA to prepare composite coating (SG/WPUA). SG can be uniformly dispersed in WPUA emulsion and is stable for a long time (28 days) without delamination. The water resistance of the composite coating with 0.3 wt.% SG nanofiller was improved; the water contact angle (WCA) result was SG/WPUA (89°) > WPUA (48.5°), and water absorption result was SG/WPUA (2.90%) < WPUA (9.98%). After water immersion treatment, SEM observation revealed that the SG/WPUA film only generated enlarged microcracks (100 nm) instead of holes (150–400 nm, WPUA film). Polarization curves and electrochemical impedance spectroscopy (EIS) tests show that SG nanosheets with low doping content (0.3 wt.%) are more conducive to the corrosion resistance of WPUA coatings, and the model was established to explain the mechanism.Keywords:waterborne polyurea;synthesis;sulfonated graphene;anti-corrosion
研究领域:
材料科学
·
化学工程
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DOI
高影响因子
危险品化学品经营许可证（带存储）