ADVANCES IN POLYMER TECHNOLOGY
·
2020
·
IF 1.539
Jing Shang,Ruonan Gao,Fu Su,Huaguang Wang,Dan Zhu
The complex rheology and the phase behavior of thermally sensitive poly(N-isopropylacrylamide) (PNIPAM) microgels have been investigated in both the swollen and collapsed states by using microrheology. To avoid the interactions between the tracer probes and the PNIPAM microgels, such as the adsorption or the depletion effect, the probes of silica (SiO2) particles have been grafted with PNIPAM chains (SiO2-PNIPAM) and characterized with Fourier transform infrared spectroscopy (FTIR). The successful preparation of SiO2-PNIPAM has also been proved by the investigation of the particle size and morphology with dynamic light scattering (DLS) and transmission electron microscope (TEM) below and beyond the phase transition temperature of PNIPAM. The microrheology of the PNIPAM microgel suspension has been investigated by using the prepared SiO2-PNIPAM particles as microrheological probes, and the results show that the diffusive coefficient of the probes in the swollen state is one-fifth of that in the collapsed state, and the viscosity of the PNIPAM microgel suspension in the swollen state is four times higher than that in the collapsed state, indicating SiO2-PNIPAM is a good probe in the microrheological study of PNIPAM microgel suspensions.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Pu Zhou,Han Dong,Wanglin Zhang,Jiachen Liu,Yefei Tian,Yi Li,Jiabei Luo,Song Xiao,Kerui Li,Hongye Yuan
Developing metal–organic framework (MOF)-based sorbents with high water-uptake capacity and mild regeneration conditions remains challenging, but is highly sought after for addressing water shortages. Herein, we report a strategy for fabricating thermal-responsive Poly (N-isopropylacrylamide) (PNIPAM)/UiO-66 composite aerogels with variable PNIPAM loading by leveraging the ordered nanopores of UiO-66 colloids, enabling the confined polymerization of NIPAM monomers within the pores, which allows for controllable water capture and release at above 32 ℃. The thermal-responsive PNIPAM/UiO-66 composite aerogels, with varying PNIPAM loadings, demonstrated an outstanding maxima water capture of over 2100 wt% at room temperature and reversible release at above 32 ℃. This performance sets a new benchmark for the leading water-capture adsorbents reported in the literature, thanks to the extensive specific surface area of the aerogels and the unique hydrophilicity-hydrophobicity transition exhibited by the PNIPAM component. More intriguingly, the aforementioned phase transition can be directly visualized by incorporating 4-(1,2,2-triphenylvinyl) benzoic acid (TPE-COOH) molecules with the well-known aggregation-induced emission (AIE) effect into the aerogels. The remarkable water-uptake ability and mild release conditions showcased in this study open new possibilities for practical water harvesting.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMER
·
2024
·
IF 4.1
Guangxu Ju,Jinzhu Tang,Qunfeng Cheng,Chunming Wang,Rui Liang,Guoxing Sun
Thermosensitive hydrogels have gained increasing attention due to their diverse applications in drug delivery and as wearable sensors. However, their practical utility is hampered by their inherent weak mechanical properties. To overcome this limitation, a tough thermosensitive hydrogel was developed by incorporating non-aggregated spherulite nanoparticles into the system. The hydrogel of poly (N-isopropylacrylamide) (PNIPAM) and calcium hydroxide nano-spherulites (CNS) exhibits a broad temperature response from 0 to 100 °C and good thermosensitivity after ten cycles in swelling experiments. The exceptional mechanical properties with a maximum tensile strength of 82.05 kPa, an elongation at break of about 3200 %, which returns to 88 % of its original size after a compressive load of 16.17 MPa, and an adhesion strength to latex of 32.45 kPa. In addition, each gram of PNIPAM/CNS hydrogel can hold 18.488 mg of AMX , which shows its potential application in many fields such as drug delivery, skin healing, bionics , etc.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
·
IF 4.9
Chi Han,Yafeng Jing,Jieling Li,Tianhe Jiang,Sen Liang,Rui Lin,Anhe Wang,Jian Yin,Yong Mao,Shuo Bai
Poly(N-isopropyl acrylamide) (PNIPAM) hydrogel, renowned for its rapid response to temperature changes, has emerged as a promising material for soft electronic and wearable biosensors. However, its practical use in wearable biosensors is hindered by challenges such as poor mechanical strength, limited conductivity, and potential biosafety concerns due to residual polymerization initiators. To overcome these limitations, an edible initiator of Vitamin C is introduced to catalyze the polymerization of NIPAM. This process is further enhanced by the addition of the biocompatible ionic liquid 1-butyl-3-methylimidazolium chloride ([BMIm][Cl]), which accelerates polymerization and improves the hydrogel’s conductivity and mechanical properties. Experimental results demonstrate that the obtained ionic hydrogel holds significant potential for wearable biosensor applications, particularly for monitoring human physiological signals.
研究领域:
材料科学
·
生物医学工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2018
·
IF 2.21
Yuanfang Xiang,M. Katherine Banks,Ruoxi Wu,Weijian Xu,Shu Chen
A thermo-sensitive graphene-based hybrid is prepared by the electrostatic interactions between the poly(diallyldimethylammonium chloride)-co-poly(N- isopropylacrylamide) (PDDA-co-PNIPAM) and graphene oxide (GO). The electrostatic interaction, chemical structure , morphology and thermo-sensibility of the hybrid are systematically characterized, which have been manifested that the electrostatic interaction between the PDDA-co-PNIPAM and GO is strong, and the employment of the cationic PDDA-co-PNIPAM results into a well distributed polymer nanoparticles on the GO sheets. The new PDDA-co-PNIPAM/GO hybrid has good dispersity in some polar solvents. Notably, the phase transition of this hybrid can be reversibly modulated by temperature in water, which can be applied as thermo-switch material for the adsorption and separation of the organic pigments in aqueous solutions.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 60
·55666-55670
·
IF 3.289
Xiao-Yan Zhang,Yan Zheng,Chun-Hua Liu,Ping-Hua Wang,Yuan-Yuan Zhu
We herein report the synthesis of fluorescent silicon nanoparticles (F-SiNPs) with uniformly small sizes and stable fluorescence, and further preparation of F-SiNPs/poly(N-isopropylacrylamide) (F-SiNPs/PNIPAM) composite hydrogels by in situ polymerization. This type of hydrogel displayed visible thermal-sensitive phase transition properties. Upon heating, the fluorescence intensity of the hydrogels decreased sharply beyond the lower critical solution temperature (LCST) of PNIPAM. The process of fluorescence quenching and recovery was reversible after repeated heating and cooling cycles. This result suggests that the present organic/inorganic hybrid F-SiNPs/PNIPAM hydrogels will have potential applications in visual detection as fluorescence-based temperature sensors.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
DOI
高影响因子
LANGMUIR
·
2024
·
IF 3.7
Jiacong Wu,Shiyuan Liu,Xinnan Ma,Cailiang Zhang,Chengxiang Feng,Lei Wang,Juan Han,Yun Wang
The current study presents a scalable approach for the preparation of temperature-responsive PEG/SiO2/PNIPAM-PEA Janus particles and, for the first time, investigates their potential applications in stabilizing foam and defoaming by adjusting the temperature. The method utilizes a (W1 + O)/W2 emulsion system, which incorporates appropriate surfactants to stabilize the emulsion and prevent rapid dissolution of the hydrophilic triblock polymer PEG-b-PTEPM-b-PNIPAM in water. The PEG/SiO2/PNIPAM-PEA Janus particles with temperature-responsive characteristics were synthesized in a single step that combined the sol–gel reaction and photoinduced free radical polymerization. The contact angle of the hydrophilic PEG/SiO2/PNIPAM surface was measured to be 54.7 ± 0.1°, while the contact angle of the hydrophobic PEA surface was found to be 122.4 ± 0.1°. By incorporating PEG/SiO2/PNIPAM-PEA Janus particles at a temperature of 25 °C, the foam’s half-life is significantly prolonged from 42 s to nearly 30 min. However, with an increase in temperature to 50 °C, the foam’s half-life rapidly diminished to only 44 s. This innovative application effectively enhances foam stabilization at low temperatures and facilitates the rapid dissipation of foam at high temperatures.
研究领域:
材料科学
·
化学工程
·
胶体与表面化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2014
·
IF 3.552
Li-Ping Wang,Yu-Chao Li,Li-Feng Chen,Chao-Lei Ban,Guang Li,Jun-Jie Ni
Poly(styrene)- b -poly(N-isopropylacrylamide) (PS- b -PNIPAM) amphiphilic diblock copolymers were synthesized via reverse iodine transfer polymerization (RITP) firstly. And then the honeycomb structured porous films were fabricated by drop the amphiphilic diblock copolymer solutions on glass substrates . The porous films were characterized using field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM), respectively. The results showed that the regular honeycomb patterned porous film was achieved successfully by employing the block copolymer with a significantly larger polystyrene block proportion into the solution and the pore diameter of the film decreases obviously with the polymer concentration increased. The effects of airflow speed and Ag particles on porous films are also discussed in this study.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Xiaoyong Zhang,Haoran Ding,Yujia Zhou,Zhaozhao Li,Yongping Bai,Lidong Zhang
Poly(N-isopropylacrylamide) (PNIPAM) enhances the reversibility and responsiveness of wearable temperature-sensitive devices. However, an open question is whether and how the hydrogel design can prevent adhesive performance loss caused by phase-transition-induced dehydration and unstable mechanical properties between devices and human skin and reduce interfacial failure. Herein, a gelatin-mesh scaffold-based hydrogel (NAGP-Gel) is constructed to inhibit dehydration and volume change, leading to stable mechanical properties, superior adhesiveness, and thermal sensing sensitivity during the phase transition. NAGP-Gel enhances the polymer chains–water interaction and weakens the degree of aggregation of polymer chains–chains, improving antidehydration properties under 45 °C conditions that are higher than the lower critical solution temperature (LCST; i.e., ∼32 °C). The mesh scaffold greatly restricts the phase-transition-induced polymer chain movement and maintains the mechanical performance. In a 60 °C environment, the maximum water loss and volume retention ratio of NAGP-Gel are only 3.58% and 97.3%, respectively. Additionally, NAGP-Gel serves as a temperature sensor, producing a stable thermal–electrical signal within the LCST range. It also can be assembled into an electronic device enabling the transmission of information and recognition of sign language via Morse code. This work broadens the application of PNIPAM in constructing intelligent hydrogels and opens the door to exploring emerging hydrogels for temperature-monitoring applications.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
·
2021
·Vol. 21
·期 4
·2174-2184
·
IF 0
Zhang Diansen,Xia Yuzheng,Gong Hongliang,Zhang Dong,Chen Xiaonong,Shi Shuxian,Lei Lei
Polylactide-b-poly(N-isopropylacrylamide)-b-polystyrene (PLA-b-PNIPAM-b-PS) triblock copolymers (tri-BCPs) with various chemical compositions (block ratio) were prepared from the combination of ring-opening polymerization and reversible addition-fragmentation
chain transfer polymerization. Subsequently, the self-assembling behaviors of these tri-BCP films obtained from spin-coating were investigated by annealing them under different solvent atmosphere. We found that these films could self-assemble into various morphologies due to the microphase
separation of incompatible copolymer blocks. Atomic force microscopy confirmed the perpendicular cylindrical morphology self-assembled from PLA4.5k-b-PNIPAM5.2k-b-PS22.4k tri-BCP film under mixed solvent atmosphere of toluene/acetone (7:3, v/v).
Self-assembled PLA cylinders are evenly distributed among the PS matrix and perpendicular to the film surface, with PNIPAM component taking place at the PLA/PS interphase. Furthermore, by etching the degradable PLA component, porous PS film decorated with PNIPAM “brushes” hoisting
channels were generated. This work provides a facile method and detailed protocol for fabricating stimuli-responsive porous films which are promising for thermoresponsive “smart” separation technologies.
研究领域:
材料科学
·
高分子化学
·
纳米技术
✓ 已验证
DOI
PubMed
POLYMER DEGRADATION AND STABILITY
·
2018
·
IF 3.193
Ke Huang,Hongyan Wu,Fan Jiang,Guozhu Shen,Lu Wang
Smart near-infrared (NIR) light-responsive poly N-isopropylacrylamide (PNIPAM) nanocomposite hydrogels were prepared by incorporating sparse chemical cross-linking of small molecules. The thermo-sensitive, NIR light-responsive, toughness and strength of the pure PNIPAM, PNIPAM-Graphene oxide(GO) and PNIPAM-GO-Zirconia(ZrO 2 ) hydrogels were invesitgated. The introduction of GO induced PNIPAM the transformation from the thermosensitive to NIR light-responsive, and the oxidized groups of GO nanosheets could physically cross-link the PNIPAM chains to increase the toughness of the hydrogel networks. The loading capability and penetration resistance of PNIPAM-GO-ZrO 2 composite hydrogel was obviously improved due to that the ZrO 2 powder stabilize the hydrogel networks and strengthen the hydrogen bond interaction with the amide groups of PNIPAM chains compared with that of the pure PNIPAM and PNIPAM-GO, respectively.
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 POLYMER SCIENCE PART A-POLYMER CHEMISTRY
·
2013
·Vol. 51
·期 10
·2142-2149
·
IF 3.543
Chen He,Ban-Kun Jin,Wei-Dong He,Xue-Song Ge,Jing Tao,Jing Yang,Sheng-Qi Chen
Long-subchain hyperbranched polystyrene (lsc-hp PSt) with uniform subchain length was obtained through copper-catalyzed azide-alkyne cycloaddition click chemistry from seesaw macromonomer of PSt having one alkynyl group anchored at the chain centre and two azido group attached to both chain ends [alkynyl-(PSt-N 3 ) 2 ]. After precipitation fraction, different portions of lsc-hp PSt having narrow overall molecular weight distribution were obtained for further grafting with alkynyl-capped poly( N -isopropylacrylamide) (alkynyl-PNIPAM), which was obtained via single-electron transfer living radical polymerization of NIPAM with propargyl 2-bromoisobutyrate as the initiator and grafted onto the peripheral azido groups of lsc-hp PSt via click chemistry. Thus, amphiphilic lsc-hp PSt grafted with PNIPAM chains (lsc-hp PSt- g -PNIPAM) was obtained and would have star-like conformation in tetrahydrofuran (THF). By replacing THF with water, lsc-hp PSt- g -PNIPAM was dissolved at molecular level in aqueous solution due to the hydrophilicity of PNIPAM and exhibited thermal induced shrinkage of PNIPAM arms. The water-insoluble lsc-hp PSt would collapse densely and could be served as a reservoir to absorb hydrophobic chemicals in aqueous solution. The influence of overall molecular weight of lsc-hp PSt on the absorption of pyrene was studied. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013
研究领域:
高分子化学
·
材料科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）