Polymers
·
2015
·Vol. 7
·期 5
·909-920
·
IF 3.681
Tao Chen,Qisheng Fang,Qi Zhong,Yangyi Chen,Jiping Wang
We tuned the lower critical solution temperature (LCST) of amphiphilic poly(N-isopropylacrylamide) (PNIPAAm) via copolymerization with a hydrophilic comonomer ofN-hydroxymethyl acrylamide (NHMAAm). A series of copolymers P(NIPAAm-co-NHMAAm) were synthesized by atom transfer radical polymerization (ATRP) using CuBr/(N,N,N',N',N''-Pentamethyldiethylenetriamine) (PMDETA) as a catalyst system and 2-bromo ethyl isobutyrate (EBiB) as an initiator. The copolymers were well characterized by Fourier transform infrared spectroscopy (FT-IR),1H Nuclear magnetic resonance (NMR), and Thermogravimetric analysis (TGA). The copolymers followed a simple rule in their thermosensitive behaviors and have a linear increase in the LCST as a function of NHMAAm mol%. The thermosensitive properties of the copolymer films were investigated and demonstrated hydrophilic-hydrophobic transitions. Finally, the copolymer was grafted onto cotton fabrics using citric acid (CA) as a crosslinking agent and sodium hypophosphite (SHP) as a catalyst following a two dipping, two padding process. The large number of hydroxyl groups in the copolymer makes grafting convenient and firm. The grafted cotton fabrics show obvious thermosensitive behaviors. The results demonstrate that the cotton fabrics become more hydrophobic when the temperature is higher than the LCST. This study presents a valuable route towards temperature-responsive smart textiles and their potential applications.Keywords:synthesis;thermosensitive behavior;copolymer;tunable LCST;smart textile
研究领域:
材料科学
·
纺织工程
✓ 已验证
产品关联
DOI
高影响因子
Advanced Optical Materials
·
2024
·Vol. 13
·期 6
·2402556
·
IF 8
Yihan Liu,Zhichao Zhang,Yingjie Mao,Kai Liu,Denghui Xu,Dan Liu,Xiong Li,Jun Zhou
Doping lanthanide ions in double perovskites (DPs) offers a promising approach to tailor optical and optoelectronic properties for versatile applications. However, achieving efficient and thermal stable DPs remains a significant challenge. In this paper, a series of Cs 2 KInCl 6 :Yb 3+ ,Er 3+ DPs with a negative thermal quenching behavior and high sensitivity are fabricated. The intrinsic luminescence properties of Cs 2 KInCl 6 are studied with a broad intrinsic self-trapped excitons (STEs) emission peak at 500 nm, which can be enhanced by doping Er 3+ ions accompanied with greater distortion of the [InCl 6 ] 3− octahedrons as well as multiple characteristic emission modes of Er 3+ under ultraviolet and near-infrared excitation. Notably, the addition of sensitizer Yb 3+ ions leads to the enhanced up-conversion emission of Er 3+ (up-conversion quantum yield up to 1.66%), anti-thermal quenching performance brought by the phonon-assisted energy transfer up-conversion process, as well as high sensitivity and reproducibility based on fluorescence intensity ratio technology. This work provides an effective strategy to enhance the STEs emission of DPs and achieve efficient optical temperature sensors through lanthanide ions doping.
研究领域:
材料科学
·
光学
·
物理学
✓ 已验证
DOI
高影响因子
POLYMER
·
2024
·
IF 4.1
Xing-Ying Zheng,Tao Li,Hua-Wen Cai,Xin-Hui Wang,Xiao-Li Sun,Wen-Ming Wan
Stimuli-responsive luminescent polymer is generally prepared by incorporation of both stimuli-responsive and luminescent moieties into polymer chain, which cause difficulties in molecular design and synthesis. The preparation of stimuli-responsive luminescent polymer from one moiety represents a time-saving approach and is highly desirable. Here, we demonstrate a simple approach to achieve stimuli-responsive luminescent polymers through polymerization-induced emission of nonemissive borinic acid moiety. Attributed to versatile borinic acid moiety, the prepared borinic acid polymer (PBA) exhibits upper critical solution temperature (UCST) type thermo-responsive behavior and chemical sensitivities. Interestingly, PBA is not only stimuli-responsive but also luminescent, while the repeating borinic acid moiety is nonemissive, indicating borinic acid is a novel PIE luminogen (PIEgen). This work therefore opens a new avenue to molecularly design stimuli-responsive luminescent polymer from nonemissive borinic acid moiety, which might cause inspirations to the fields of boron chemistry, stimuli-responsive polymer and luminescent polymer.
研究领域:
高分子化学
·
发光材料
·
刺激响应性材料
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2016
·Vol. 8
·期 4
·110
·
IF 2.944
Boxiang Wang,Xiaolin Wu,Jia Li,Xu Hao,Jie Lin,Dehong Cheng,Yanhua Lu
To increase the themosensitive behavior and antibacterial activity of cotton fabric, a series of poly (N-isopropylacrylamide)/chitosan (PNIPAAm/Cs) hydrogels was synthesized by interpenetrating polymer network (IPN) technology using a redox initiator. The IPN PNIPAAm/Cs hydrogel was characterized by Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The results indicated that the IPN PNIPAAm/Cs hydrogel has a lower critical solution temperature (LCST) at 33 °C. The IPN hydrogel was then used to modify cotton fabric using glutaric dialdehyde (GA) as a crosslinking agent following a double-dip-double-nip process. The results demonstrated that the modified cotton fabric showed obvious thermosensitive behavior and antibacterial activity. The contact angle of the modified cotton fabric has a sharp rise around 33 °C, and the modified cotton fabric showed an obvious thermosensitive behavior. The bacterial reduction of modified cotton fabric againstStaphylococcus aureus(S. aureus) andEscherichia coli(E. coli) were more than 99%. This study presents a valuable route towards smart textiles and their applications in functional clothing.Keywords:chitosan;interpenetrating polymer network hydrogel;cotton fabric;thermosensitive behavior;antibacterial activity
研究领域:
材料科学
·
纺织工程
·
生物医学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS CHEMISTRY
·
2011
·Vol. 21
·期 35
·13611-13620
·
IF 5.101
Xiaomeng Wu,Xiaohua He,Liang Zhong,Shaoliang Lin,Dali Wang,Xinyuan Zhu,Deyue Yan
One route has been employed to prepare dendritic-linear block copolymer modified superparamagnetic iron oxide nanoparticles (SPIONs), which consist of a Fe3O4 magnetic nanoparticle core and a dendritic-linear block copolymer, the focal point polyamidoamine-type dendron-b-poly(2-dimethylaminoethyl methacrylate)-b-poly(N-isopropylacrylamide) (PAMAM-b-PDMAEMA-b-PNIPAM) shell by two-step atom transfer radical polymerization (ATRP). Firstly, Fe3O4 nanoparticles were prepared by a high-temperature solution phase reaction in the presence of iron(III) acetylacetonate [Fe(acac)3], oleic acid and oleylamine. Then propargyl focal point PAMAM-type dendron (generation 2.0, denoted as propargyl-D2.0) with four carboxyl acid end groups as a cap displaced the oleic acid and oleylamine on the surfaces. Subsequently, an initiator for ATRP was introduced onto the propargyl-D2.0-modified Fe3O4 nanoparticle surfaces via click chemistry with 2′-azidoethyl-2-bromoisobutylate (AEBIB). PDMAEMA and PNIPAM were grown gradually from nanoparticle surfaces using two-step copper-mediated ATRP. Finally, a crosslinking reaction between PDMAEMA block with 1,2-bis(2-iodoethoxy)ethane (BIEE) was used to stabilize the nanoparticles and reverse aggregation. The modified nanoparticles were subjected to detailed characterization using FT-IR, DLS, XRD and TGA. Magnetization measurements confirmed the characteristic superparamagnetic behavior of all magnetic nanoparticles under room temperature. In addition, doxorubicin (DOX) as an anticancer drug model was loaded into the dendritic-linear block copolymer shell of the modified nanoparticles, and subsequently the drug release was performed in phosphoric acid buffer solution (pH 7.4) at 25 °C or 37 °C. The results verify that dendritic-linear block copolymer-modified nanoparticles as a drug carrier possess thermosensitive drug release behaviors. Furthermore, a methyl tetrazolium (MTT) assay of DOX-loaded dendritic-linear block copolymer-modified nanoparticles against Hela cells was evaluated. The results show that the modified nanoparticles can be used for drug delivery.
研究领域:
材料科学
·
药学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
·
2013
·Vol. 51
·期 11
·2409-2415
·
IF 3.543
Jing Li,Xufeng Ni,Jun Ling,Zhiquan Shen
Polymerization of diethyl vinylphosphonate (DEVP) is achieved by using lanthanide tris(borohydride) complexes, Ln(BH 4 ) 3 (THF) 3 (Ln = Y, La, Nd, Sm, Gd, Dy, Lu) as an initiator. The characteristics and mechanism of polymerization as well as the properties of the resulting poly(diethyl vinylphophonate)s (PDEVPs) are studied. The effects of the lanthanide elements, the molar ratios of monomer to initiator ([ M ]/[ln]), reaction temperature and time on polymerization have been investigated in detail. The optimized polymerization conditions are 40 °C, 1 h in bulk with [ M ]/[ln] = 300. The kinetic study indicates that the polymerization of DEVP undergoes a controlled manner as the molecular weights (MWs) of PDEVPs increase with monomer conversion linearly maintaining moderate MW distribution (1.7–1.9). Additionally, a coordination anionic polymerization mechanism is proved by end-group analysis with ESI mass and 1 H NMR spectroscopy. The obtained PDEVPs have low glass transition temperature ( T g = −62 °C) and high thermal decomposition temperature ( T d > 300 °C) determined by differential scanning calorimetry and thermogravimetric analysis respectively. The thermosensitive behavior of PDEVP is characterized by evaluating the lower critical solution temperature of PDEVP in water by ultraviolet transmittance. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2409–2415
研究领域:
高分子化学
·
材料科学
✓ 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）