POLYMER
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2022
·
IF 4.432
Yu-Lin Hong,Jian Sun,Hong-Wei Yang,Chang Wang,Yun Liu,Zhi-Wei Tan,Cheng-Mei Liu
Nitrile-rich polymers have found applications in carbon fibre, functional materials and rubber industry, though nitrile-rich polyelectrolytes have seldom been reported before. Here we present a nitrile-rich reactive phosphonium-based polyelectrolyte (PVBzTCPC) synthesized by the RAFT polymerization of 4-vinylbenzyl-tris(2-cyanoethyl)phosphonium chloride (VBzTCPC), a CN-rich phosphonium monomer prepared from tris(2-cyanoethyl)phosphine (TCP) and 4-vinylbenzyl chloride. The RAFT polymerization behaviour of the monomer was studied and it was found that the polymerization of monomer proceeded in a controlled/living manner. PVBzTCPC underwent the Wittig reaction and vinyl groups were introduced into the polymer chain as polymerizable pendant groups. Post-polymerization modifications of PVBzTCPC through the nitrile group proceeded successfully and the modified polymers were also phosphonium-based polyelectrolytes. PVBzTCPC showed a high tendency to form an undissolved polyelectrolyte complex with sodium perfluorooctanoate in aqueous solution, which provided a possible way of removing this persistent organic pollutant from water. The DMF solution of CN-rich PVBzTCPC showed LCST-type (lower critical solution temperature) phase transition without adding any foreign salts over 100 °C, and a possible mechanism of LCST transition was proposed.
研究领域:
材料科学
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化学工程
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Polymer Chemistry
·
2017
·Vol. 8
·期 37
·5749-5760
·
IF 5.375
Hongcan Zhang,Jian Zhang,Wenxue Dai,Youliang Zhao
The simple and straightforward construction of multi-responsive systems with tunable LCST and UCST dual phase transitions is a great challenge. This study affords an efficient route to tune cloud points via control over the chemical composition of hydroxyl and diethylamino bearing poly(amido thioether)s which were prepared by one-pot thiol–amine–acrylate polyaddition. Owing to the balance of inter/intrachain interactions, various copolymers could exhibit LCST (fOH < 0.84), LCST–UCST (fOH = 0.84–0.89) and UCST (fOH > 0.89) behaviors relying on the hydroxyl fraction in comonomer units. Meanwhile, the thermoresponsive behaviors of copolymer solutions could be efficiently tuned via switching the solvent and solution pH, applying CO2/N2 bubbling, and oxidation. The success of this study further paves the way for the robust synthesis and practical applications of smart polymers with double thermoresponsivity.
研究领域:
高分子化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
BIOMACROMOLECULES
·
2018
·
IF 5.738
Chao Xing,Zhekun Shi,Jiliang Tian,Jing Sun,Zhibo Li
Stimuli-responsive polymers have received increasing interest for a variety of applications. Here, we report a series of unique charge-determined thermoresponsive polypeptoids synthesized by a combination of ring-opening polymerization and click chemistry. The LCST-type and UCST-type behavior is mainly dominated by the charge state on the side chain. Further, the phase transition temperature highly depends on the degree of polymerization, the side-chain architecture, the pH value, and so on. The obtained polypeptoid solutions exhibit good stability against temperature and salt concentration. To our knowledge, this report presents the first charge-determined LCST/UCST-type polymer from identical homopolymer backbone that displays a wide range of tunable cloudy points in aqueous media. We propose the hydrogen-bonding interaction plays a critical part on the solution behavior. These features make polypeptoids ideal candidates for highly designable stimuli-responsive polymeric materials.
研究领域:
高分子化学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2022
·
IF 6.633
Xinyu Ma,Yingjuan Zhang,Shuwei Cai,Xianru He
Copolymers of N-vinylpyrrolidone (NVP) and methyl acrylate (MA) were prepared via reversible addition-fragmentation chain transfer (RAFT) polymerization, which exhibited typical lower critical solution temperature (LCST) behavior in aqueous solution. The molecular structure and composition of copolymer P(NVP-co-MA) were characterized by FTIR and NMR. The response behavior was investigated by UV transmittance tests. The LCST of the copolymer P(NVP-co-MA) can vary from 17 °C to 90 °C by adjusting the ratio of the two monomers, showing a wide tunable range. The dynamic light scattering (DLS) results showed that beyond LCST, the hydrodynamic size increased with increasing temperature, polymer molecular chains aggregated in solution, and solubility deteriorated, confirming its LCST responsiveness. In addition, the copolymer P(NVP-co-MA) is salt responsive as well as pH-responsive. The multi-responsive and biocompatible copolymer has a large potential application in the fields of materials and biomedicine.
研究领域:
材料科学
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生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
Soft Matter
·
2014
·Vol. 10
·期 16
·2856-2862
·
IF 4.151
Lvdan Liu,Yang Shi,Chang Liu,Tao Wang,Guangming Liu,Guangzhao Zhang
Methylated urea and sugar are chaotropic and kosmotropic osmolytes, respectively. In the present work, we have investigated the specific anion effect on the lower critical solution temperature (LCST) behavior of poly(N-isopropylacrylamide) (PNIPAM) in the presence of methylated urea or sugars. Differential scanning calorimetry studies revealed that tetramethylurea can adsorb onto the PNIPAM surface, but glucose is excluded from the PNIPAM surface. The specific anion effect on the LCST behavior of PNIPAM is amplified by methylated urea but not by sugars. The amplification of the anion specificity by methylated urea is attributed to an increased difference in the anion-specific polarization of hydrogen bonds, induced by the formation of PNIPAM/methylated urea complexes via hydrophobic interactions. As the number of methyl groups on the methylated urea increases, the extent of amplification of the anion specificity increases due to increasing hydrophobic interactions between the PNIPAM and methylated urea. Additionally, no amplification of the anion specificity is observed in the presence of urea because a PNIPAM/urea complex cannot be formed via hydrophobic interactions.
研究领域:
生物化学
·
高分子化学
✓ 已验证
DOI
高影响因子
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