LANGMUIR
·
2024
·
IF 3.7
Haotian Duan,Tianfeng Zhou,Beibei Li,Yuxia Pang,Hongming Lou,Dongjie Yang,Xueqing Qiu
Polycarboxylate superplasticizers (PCEs) achieve dispersion mainly via steric hindrance from poly(ether) side chains. However, long side chains may cause structural collapse. This study mitigates this issue by introducing sulfonic acid terminations to the long side chains, synthesizing sulfonic-terminated polycarboxylates (PCEPS). Electrostatic repulsion between sulfonic and carboxyl groups on the main chain reduces the level of collapse, enhancing PCE dispersion in cement. PCEPS-4000 showed the strongest dispersion compared with conventional PCEs (PCEC). PCEPS-4000 formed an adsorption layer thickness (ALT) of 11.65 nm, showing a significant improvement over the 7.93 nm observed in the carboxyl-terminated long side chain polycarboxylate (PCETA). Stronger negative charge and lower complexation of sulfonic acid groups enhance the side chain extension. PCEPS also shows good clay tolerance and slump retention, proving its versatility as a concrete admixture.
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
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2021
·
IF 5.816
Hui Wang,Xinming Du,Hongyu Zhang,Hongcheng Shen,Qian Liu,Zhe Wang
A series of quaternary ammonium salt poly(ether ether ketone) AEMs containing long ether substituents are successfully prepared, and their chemical structure is confirmed by 1 H NMR and FT-IR. The distinct microphase separation morphology of AEMs is observed by TEM. As the content of methylhydroquinone increases, the ion conductivity of AEMs gradually increases. When the content of methylhydroquinone increases to 80%, the hydroxide conductivity of PEEK-DABDA-80 membrane reaches 0.052 S/cm at 80 °C. Meanwhile, it exhibits excellent mechanical properties and anti-swelling ability, with tensile strength of 25 MPa, elongation at break of 8.12% and swelling ratio is only 17.4% at 80 °C. And AEMs also display the better thermal stability. After soaked in 1 M NaOH at 60 °C for 30 days, PEEK-DABDA-80 membrane shows acceptable ion conductivity of 0.021 S/cm at 60 °C. In view of these properties, PEEK-DABDA-x AEMs may display potential application as alkaline AEMs.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2023
·Vol. 140
·期 23
·e53931
·
IF 3
Zhenzhong Li,Tianfeng Zhou,Hai Liu,Yu Jin,Yuxia Pang,Hongming Lou,Dongjie Yang,Xueqing Qiu
The steric hindrance formed by polyether side chains is the key factor determining the dispersion performance of polycarboxylate superplasticizer (PCE). While with the increase of the side chain length, the coiled conformation of side chain will prevent the dispersion ability of PCE from being further improved. In this work, the methallyl polyoxyethylene ether (HPEG) was esterified with tricarballylic acid (TA) to obtain dicarboxyl terminated macromonomer, and further used to synthesize polycarboxylate (PCETA). The fluidity tests show that compared with ordinary PCE-B2400 with short side chain, the dispersion performance of PCETA-2400 was slightly improved. While for the PCEs with long side chain, the dispersion ability of PCETA-4000 was significantly improved than that of ordinary PCE-B4000. The adsorption layer thickness of PCETA-4000 adsorbed on the surface of SiO 2 sphere measured by dynamic light scattering is 7.93 nm, which is 1.3 times that of PCE-B4000. Due to electrostatic repulsion between the carboxylic groups, the stretching of long side-chain forms stronger steric hindrance and enhancing the dispersion of cement particles. In addition, PCETA also shows good slump retention and clay resistance properties, and it is an excellent multi-functional concrete admixture with great application potential.
研究领域:
建筑材料化学
·
胶体化学
✓ 已验证
产品关联
DOI
高影响因子
Energies
·
2021
·Vol. 14
·期 24
·8243
·
IF 3.004
Xinyuan Li,Shu Lu,Meifei Niu,Ruzhen Cheng,Yanjun Gong,Jun Xu
A high content of asphaltene and wax in crude oil leads to difficulties in the recovery and transportation of crude oil due to the precipitation of asphaltenes and the deposition of waxes. Comb-like polymers were found to be capable of inhibiting the aggregation of asphaltenes and crystallization of waxes. In this work, comb-like bipolymers of α-olefins/ultra-long chain (C18, C22 and C28) alkyl acrylate were synthesized and characterized by FT-IR and1H NMR spectra. The results show that, for a model oil containing asphaltene, the initial precipitation point (IPP) of asphaltene was prolonged by UV, and the asphaltene particle size was reduced after adding the biopolymers, as revealed by dynamitic light scattering (DLS). The bipolymer containing the longer alkyl chain had a better asphaltene inhibition effect. However, DSC and rheological results show that the wax appearance temperature (WAT) of the typical high asphaltene and high wax content of crude oil was obviously reduced by adding bipolymers with shorter alkyl chains. The bipolymer (TDA2024-22) with a mediate alkyl chain (C22) reduced the viscosity and thixotropy of the crude oil by a much larger margin than others. Compared with the previously synthesized bipolymer with phenyl pendant (PDV-A-18), TDA2024-22 exhibited a better performance. Therefore, bipolymers with appropriate alkyl side chains can act as not only the asphaltene inhibitors but also wax inhibitors for high asphaltene and wax content of crude oil, which has great potential applications in the oil fields.
研究领域:
石油工程
·
材料科学
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2025
·
IF 5.4
Haotian Duan,Beibei Li,Tianfeng Zhou,Yuxia Pang,Hongming Lou,Dongjie Yang,Xueqing Qiu
For polycarboxylate superplasticizers (PCEs) with long side chains ( M w ≥ 2400 Da), the introduction of negatively charged groups at side-chain terminals leverages electrostatic repulsion to mitigate tail-end collapse of long side chains, thereby enhancing steric hindrance. However, such functionalization may impact the adsorption and dispersion behaviors of PCEs. In this study, sulfamic acid (SA) was employed to achieve sulfonic acid termination of long-side-chain PCEs ( M w = 4000 Da). The effects of distinct terminal groups (sulfonic acid vs. carboxylic acid) and charge densities (single-group vs. double-group) on adsorption and dispersion performances were systematically investigated. The primary sample was disulfonic acid-terminated PCE (PCE-DS), whereas control samples included conventional PCE (PCE), monosulfonic-terminated PCE (PCE-SS), and dicarboxylic-terminated PCE (PCE-DA). Results showed that PCE-DS exhibited superior dispersion performance and enhanced water-reducing efficiency in concrete. Compared with control samples, PCE-DS outperformed due to enhanced electrostatic repulsion from terminal sulfonic acid groups on side chains and reduced complexation with cement ions, which optimized its adsorption conformation on cement particles and within pore solution. This mitigation of dual-end side-chain adsorption enabled PCE-DS side chains to assume a more extended conformation, thereby generating stronger steric hindrance and ultimately enhancing adsorption and dispersion capabilities.
研究领域:
材料科学
·
混凝土外加剂
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULES
·
2019
·
IF 5.997
Jinxian Yang,Yixia Li,Nairong Hao,Ahmad Umair,Anhong Liu,Lianwei Li,Xiaodong Ye
The controlled degradation of amphiphilic hyperbranched polymers (AHPs) is the first consideration for their bio-related applications. In this contribution, we aim to get some insight into the effect of block distribution and composition on the degradation behavior of AHPs model systems. Degradable amphiphilic hyperbranched block (Hyperblock) and graft (Hypergraft) copolymers with hydrophobic poly(ε-caprolactone) (PCL) and hydrophilic poly[tri(ethylene glycol) methyl ether acrylate] (PTEGMA) as building blocks were prepared in this study, i.e., HB-PCL-b-PTEGMA and HB-PCL-g-PTEGMA. The two kinds of AHPs own cleavable disulfide linkages embedded at all branching sites. Their degradation behavior was comparatively investigated in aqueous solutions. The results reveal that the block distribution and composition play different roles in the regulation of degradation behavior of long-subchain hyperbranched self-assembly amphiphiles (SAs). Namely, the degradation process is mainly affected by chain architecture of resultant SAs, while for a given architecture, the degradation rate can be regulated by systematically varying the block composition.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2020
·
IF 7.183
Bin Shen,Balakondareddy Sana,Hongting Pu
To meet highly conductive and chemical stable anion exchange membranes (AEMs), a series of multi-block poly(ether sulfone)s with long side chains densely terminated by piperidinium (bPES-Pip-X-Y) are synthesized. The multi-block structure and the aggregation of ionic groups on the flexible side chains are responsible for the distinct hydrophilic/hydrophobic microphase separation , which can be observed via transmission electron microscopy (TEM). The resulted membranes achieve the high conductivity (in-plane) of 48.5–105.4 mS cm −1 at 80 °C. Moreover, the AEMs prepared exhibit good alkaline stability due to the presence of cation-terminated long side chain structure. The bPES-Pip-10-5 membrane still maintains 88% of the original conductivity after treated in 1 M KOH solution at 60 °C for 336 h. The membrane electrode assembly based on bPES-Pip-10-5 with a power density of 136.9 mW cm −2 at a current density of 292.5 mA cm −2 is obtained.
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
BMC Chemistry
·
2023
·Vol. 17
·期 1
·1-9
·
IF 4.6
Jing Xianwu,Liu Youquan,Zhao Wanwei,Pu Junhong
Different from common hydrophobic associative polymers, a new hydrophobic associative polyacrylamide (HAPAM) with ultra-long side chains was synthesized and aimed to be used as drag reducer in this work. Firstly, a water-soluble hydrophobic monomer (named AT114) was obtained by alcoholysis reaction with acryloyl chloride and triton 114, then the drag reducer was obtained by radical copolymerization of AM, AMPS and AT114. The structures of AT114 and drag reducer were characterized by IR and NMR. Slick water was obtained by dissolving a small amount drag reducer in water. Although the viscosity of slick water varied greatly in fresh water and brine, the drag reduction rate always remained at a high level when flowing in pipelines. When the concentration of the drag reducer was 0.03% in fresh water, drag reduction rate can be up to 76.7%, while in high concentration brine, still as high as 76.2%. It shows that salt has no obvious negative impact on the drag reduction rate. That is also to say, in the case of low viscosity, the viscosity change has no obvious impact on drag reduction rate. From the Cryo-TEM observation, it can be concluded that the drag reducer forms sparse network structures in water, which is the direct reason for drag reducing effect. This finding provides knowledge regarding the development of new drag reducers.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF POLYMER RESEARCH
·
2022
·Vol. 29
·期 11
·1-13
·
IF 3.061
Xu Jingmei,Meng Lingxin,Shi Qingyuan,Ren Qiang,Wang Zhe
In this study, sulfonated poly (ether ketone sulfone)s polymers with long sulfonic acid alkyl side chains and amino groups were prepared by free radical and polycondensation reaction. Poly (ether ketone)s with carboxyl groups were used for macromolecule crosslinking agent to prepare cross-linked membranes by amidation reaction. This series of membranes were characterized by FT-IR and 1 H NMR. Meanwhile, cross-linked composite membranes possessed excellent mechanical properties, methanol resistance performance and thermal stability. The highest proton conductivity of 0.096 S cm −1 was observed for APD-3/CP at 80 °C. The range of methanol permeation coefficients for the prepared membranes (2.89 × 10 −7 cm 2 s −1 —4.95 × 10 −7 cm 2 s −1 ) was far lower as compared to that of Nafion 117 (24.1 × 10 −7 cm 2 s −1 ). The results of morphology, swelling ratio and proton conductivity showed that the hydrophilic-hydrophobic phase separation structure effectively improved the properties of the membrane namely water uptake, dimensional stability and proton conductivity. Long-side chains functionalized cross-linked sulfonated poly (ether ketone sulfone)s proton exchange membranes had good candidate for application in fuel cells.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2023
·
IF 6
Zhejing Zhang,Na Yu,Haoran Sun,Ruihong Liu,Yixin Xu,Jingshuai Yang
The synthesis of high-performance membranes is one of the most momentous issues for alkaline energy devices. To develop anion exchange membranes (AEMs) that combine high chemical stability and ionic conductivity, we have designed and prepared a series of AEMs based on poly(ether ketone cardo) (PEKC). Through a facile lactamization procedure between the cardo phenolphthalein group in PEKC and the amino group in 1-(2-aminoethyl)-4-methylpiperazine (AP), the flexible side-chain methylpiperazine group is introduced into the PEKC backbone. By using iodomethane (Me), 1-bromopentane (Pe) and 1-(5-bromopentyl)-1-methylpiperdinium bromide (Pip) as the quaternized regents for the methylpiperazine group, three different AEMs (named PEKC-AP-Me, PEKC-AP-Pe and PEKC-AP-Pip, respectively) are developed. Comparing with alkyl side chain grafted membranes, the PEKC-AP-Pip membrane with bis-cation groups exhibits the highest OH − conductivity of 60.3 mS cm −1 (80 °C) when its corresponding IEC is 1.13 mmol g −1 . Meanwhile, the PEKC-AP-Me, PEKC-AP-Pe and PEKC-AP-Pip membranes show excellent mechanical strengths of 36.2 MPa, 32.3 MPa and 26.3 MPa, respectively. Due to the good chemical stability of piperdinium cation and PEKC-AP main chain, the long side chain grafted AEMs also demonstrate good alkaline stability. When submersing in 1 M KOH solution at 80 °C, PEKC-AP- x membranes maintain their conductivities up to 1200 h. These good comprehensive properties grant the prepared PEKC-AP- x membranes ambitious future for alkaline energy devices.
研究领域:
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2021
·
IF 5.816
Fanghui Wang,Conghui Li,Jing Sang,Yahui Cui,Hong Zhu
By choosing a triple block polymer , poly(styrene- b -(ethylene- co -butylene)- b -styrene) (SEBS), as the backbone and adopting a long side-chain double-cation crosslinking strategy, a series of SEBS-based anion-exchange membranes (AEMs) was successively synthesized by chloromethylation , quaternization , crosslinking, solution casting , and alkalization. The 70C16-SEBS-TMHDA membrane showed high OH − conductivity (72.13 mS/cm at 80 °C) and excellent alkali stability (only 10.86% degradation in OH − conductivity after soaking in 4-M NaOH for 1700 h at 80 °C). Furthermore, the SR was only 9.3% at 80 °C and the peak power density of the H 2 /O 2 single cell was up to 189 mW/cm 2 at a current density of 350 mA/cm 2 at 80 °C. By introducing long flexible side chains into a polymer SEBS backbone, the structure of the hydrophilic–hydrophobic microphase separation in the membrane was constructed to improve the ionic conductivity . Additionally, network crosslinked structure improved dimensional stability and mechanical properties .
研究领域:
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2024
·
IF 6.5
Yinghu Song,Guojun Song,Jialiang Li,Xirui Yang,Zhaoji Li,Xiaoru Li
Developing elastomers with both high mechanical strength and reparability remains a formidable challenge. In this work, asymmetric six-membered ring structures and long side chain structures were introduced into the molecular main chain and side chain, respectively. This caused the hard domains within the molecular chain to be loosely packed, forming asymmetric dynamic hard domain structures. At the same time, multi-level asymmetric hydrogen bond structures were formed between molecules. The structure and properties of the materials were characterized and tested using infrared spectroscopy, mechanical property testing, dynamic mechanical analysis, and contact angle measurement. The experimental results showed that the resulting polyurethane elastomer exhibited strong tensile strength, reaching up to 54.4 MPa, excellent elongation at break (648 %), and good self-healing efficiency (87.8 %). Additionally, using interfacial composite technology, hydrophobically modified TiO 2 nanoparticles were compounded with polyurethane to prepare a super-hydrophobic surface coating with a contact angle of up to 160°. This coating demonstrated excellent acid and alkali resistance, wear resistance, and water droplet impact resistance. The multifunctional composite materials prepared in this study have broad potential applications in the fields of coatings and flexible hydrophobic films.
研究领域:
材料科学
·
高分子化学
·
表面科学
✓ 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）