COLLOID AND POLYMER SCIENCE
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2020
·Vol. 298
·期 10
·1285-1291
·
IF 1.536
Xie Chuanbao,Leng Kangwei,Sheng Jie,Wang Xuemei,Li Qianmin,Song Liang,Liu Lei,Sun Hejing,Huang Xiaowen,Wang Zhongwei,Yu Qing
Poly(methyl methacrylate) (PMMA) microspheres were synthesized through visible light–induced photopolymerization of methyl methacrylate (MMA). 2,4,6-Trimethylbenzoyldipenylphosphine oxide (TPO), polyvinylpyrrolidone (PVP), and light-emitting diodes (LEDs) were used as the photoinitiator, stabilizer, and light source, respectively. No other additive was involved. The effect of LEDs, TPO, and PVP was discussed. Results showed that PMMA microspheres with the size of 0.5–0.8 μm could be obtained when LED@385 nm was the light source, and the content of TPO and PVP was 2 wt% and 30 wt% of MMA. Moreover, the possible formation pathway of PMMA microspheres was proposed based on the investigation of reaction time and addition method of PVP.
Graphical abstract
研究领域:
材料科学
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化学工程
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DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2024
·Vol. 142
·期 10
·e56550
·
IF 2.7
Yuhang Huang,Yingkang Zhu,Lijun Cao,Yidan Jing,Zhigang Xu,Guochu Tang,You Shu,Xiaoqing Liu,Xiaomin Zhang
The photo-induced cis-trans isomerization of azobenzene molecules, known for their significant color changes, is extensively utilized in the functional modification of polymeric materials. However, the research on the functionalization of biomass-based polyesters with azobenzene is limited. A key raw material for biomass-based coatings possess reactive double bonds and excellent film-forming capabilities, offering significant advantages for azobenzene functionalization in biomass-based polyester applications. In this study, AESO served as the polyester matrix and acrylate azobenzene derivatives as the functional molecules. Under ultraviolet radiation, AESO underwent a carbon–carbon crosslinking reaction with the azobenzene derivatives to synthesize a novel resin. The coating of this resin on a PET substrate exhibited excellent pencil hardness (3B), adhesion (5B), and solvent resistance. By alternating exposure to ultraviolet and blue light, the coating displayed reversible switching between cis and trans isomers, enabling reversible writing and erasing of patterns. Even after 20 cycles of writing and erasing, high-resolution patterns could still be observed (clearly visible under a 12x microscope). Furthermore, the image could be retained for up to 2 h under sunlight irradiation. This study presents a new method for functionalizing biobased polyesters.
研究领域:
材料科学
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生物质化学
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光学材料
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DOI
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
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2021
·Vol. 413
·期 15
·3945-3953
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IF 4.157
Yang Jin,Chen Weixing,Chen Xinyu,Zhang Xi,Zhou Hongwei,Du Haotian,Wang Mingcheng,Ma Yiting,Jin Xilang
Novel spherical polymer nanoparticles were synthesized by hyperbranched polyethylenimine (hPEI) and 6-hydroxy-2-naphthaldehyde (HNA) via Schiff base reaction (one-pot reaction), which had great advantages in water solubility and green synthesis. Meanwhile, probe PEI-HNA could quickly detect Cu 2+ in the range of 0–60 μM in 30 s with the detection limit of 243 nM. The fluorescence of PEI-HNA-Cu 2+ could be recovered by the addition of S 2− in 50 s with the detection limit of 227 nM. Based on the excellent optical properties, PEI-HNA has been used in the bioimaging of living cells with excellent cell penetrability and low toxicity. More importantly, PEI-HNA has been doped into filter paper, hydrogel, and nanofibrous film to prepare solid-phase sensors, displaying rapid response and excellent sensitivity. Moreover, the low-cost and simple preparation of these sensors offers great potential and possibilities for industrialization, which could help accelerate the development of sensors in environmental and biological fields.
研究领域:
分析化学
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生物医学工程
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材料科学
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产品关联
DOI
PubMed
高影响因子
PROGRESS IN ORGANIC COATINGS
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2016
·
IF 2.632
Jiahui Su,Xiaoxuan Liu,Chengjing Xiong,Hong Huang,Yanyan Cui
In this study, we prepared a novel triblock copolymer, PDMS- b -(PMAEBB- co -PDMAEMA) 2 ( tri -PI) bearing side-chain benzophenone (BP) and coinitiator amine, as a macro-photoinitiator via reversible addition-fragmentation chain transfer (RAFT) copolymerization of the polymerizable photoinitiator 2-(methacryloyloxy)ethyl-2-benzoylbenzoate (MAEBB) and the unsaturated coinitiator amine 2-(dimethylamino)ethyl methacrylate (DMAEMA) with a bifunctional polydimethylsiloxane (PDMS) macro-chain transfer agent (macro-CTA). The structure of synthesized copolymer was confirmed by Fourier-transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance ( 1 H NMR), differential scanning calorimetry (DSC), and gel permeation chromatography (GPC). The effects of the photoinitiator/coinitiator ratio, concentration, and photoinitiator systems on the photopolymerization kinetics of tri(propylene glycol) diacrylate (TPGDA) were investigated by real-time FT-IR. The mobility of the tri -PI chain segments was proven by X-ray photoelectron spectroscopy (XPS), and the surface morphology of TPGDA curing coatings was studied by scanning electron microscopy (SEM). Results showed that tri-PI strongly suppressed the effect of oxygen inhibition on the photopolymerization system. Tri-PI was also used in the curing of UV-curable waterborne polyurethane acrylate (UV-WPUA) resin to determine its versatility.
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
Polymers
·
2017
·Vol. 9
·期 6
·233
·
IF 3.364
Fei Wang,Leishan Shao,Qiyao Bai,Xinyuan Che,Bin Liu,Yinghan Wang
Vertical alignment of liquid crystal (LC) was achieved in an easy and effective way: in situ photopolymerization of dodecyl acrylate (DA) monomers initiated by polyimide based on 3,3′,4,4′-benzophenonetetracarboxylic dianhydride and 3,3′-dimethyl-4,4′-diaminodiphenyl methane (BTDA-DMMDA PI). The alignment behavior and alignment stabilities were characterized by a polarizing optical microscope (POM), which showed a stable vertical alignment after 12 h of thermal treatment. The chemical structures, morphology, and water contact angles of alignment films peeled from LC cells with and without DA monomers were analyzed by means of a Fourier transform infrared spectrometer (FTIR), a scanning electron microscope (SEM), and a contact angle tester, separately. The results confirmed that the DA monomers underwent self-polymerization and grafting polymerization initiated by the BTDA-DMMDA PI under ultraviolet irradiation, which aggregated on the surfaces of PI films. The water contact angles of the alignment films were about 15° higher, indicating a relative lower surface energy. In conclusion, the vertical alignment of LC was introduced by the low surface free energy of PI films grafted with DA polymer and intermolecular interactions between LC and DA polymers.Keywords:vertical alignment;photopolymerization;alignment stability;surface free energy
研究领域:
材料科学
·
化学
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产品关联
DOI
PubMed
高影响因子
Additive Manufacturing
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2022
·
IF 11.632
Shufeng Xiong,Jian Liu,Jiwei Cao,Ziyong Li,Muhammad Idrees,Xiao Lin,Zhongyu Long,Zhiyuan Liu,Pei Wang,Changyong Liu,Zhangwei Chen
Previous research often failed to prepared polymer-derived SiOC ceramic components with dense and thick monoliths/skeletons based on additive manufacturing processes, due to the porosities and cracks generated during the pyrolysis process . Herein, we report a simple solution which combines the introduction of phenolic resin (PR) as an additive and the use of controlled strategy of pyrolysis, for the vat photopolymerization additively manufactured SiOC ceramics. As a result, crack-free dense monolith and lattice skeleton structural polymer-derived SiOC ceramics are successfully prepared despite the low ceramic yield of 19.3 wt% and large linear shrinkage of 50% generated after pyrolysis. The prepared dense monoliths possess a thickness of over 5 mm and the lattices show attainable maximum dense skeletons thickness of ~2 mm. The maximum dense thickness of the samples after pyrolysis is over 7 times that of other samples prepared based on additive manufacturing reported in the literature. As an indicator of dimensional retention, the specific dense thickness to ceramic yield ratio (T/Y) is deduced, resulting maximum values of 101.9 µm/(wt%) for lattice skeletons and 254.7 µm/(wt%) for monoliths. The former is even larger than that for dense monolith SiOC structures prepared by other conventional gel casting and isostatic pressing techniques with much higher ceramic yields of > 80 wt%, and is about 6.1 times the largest T/Y ratio (=16.7 µm/(wt%)) achievable in the AM-based works reported in the literature. This shows predominance of the current work over other types of polymer-derived ceramic structures prepared by additive manufacturing and even conventional methods. The lattice structures’ apparent density and specific strength reached 0.55 g/cm 3 and 6.6 × 10 4 N∙m/kg, respectively. The mechanical performance surpasses other structural polymer-derived ceramic structures with similar apparent density reported in the literature. Through the advanced characterization and analysis of material phase and morphology evolution during the pyrolysis process, the mechanism of defect-free densification is revealed. That is, the introduction of PR enables a highly smooth gas-releasing process due to the generation of ordered gas-releasing channels in the sample bodies during the pyrolysis process. As a result, the generation of cracks and defects was successfully prevented. Moreover, due to the high carbon residue of the PR, the samples containing 15 wt% PR in the preceramic state still possessed amorphous SiOC ceramics after pyrolysis at 1400 ℃, while 0 wt% PR samples showed SiC crystallization. Compared with similar materials reported, the ceramics prepared in this study exhibit enhanced structural and mechanical performance. The strategy investigated in the study can be a viable route for the additive manufacturing of high-performance crack-free and thick monolith and lattice skeleton SiOC ceramic structures based on vat photopolymerization.
研究领域:
材料科学
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制造工程
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产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2015
·Vol. 133
·期 10
·
IF 1.768
Xuying Nan,Yi Huang,Qinguo Fan,Jianzhong Shao,Yuhua Yao
Three dye-linked photoinitiators with excellent spectral stability in an acid medium were synthesized by the covalent bonding of a coinitiator (tertiary amine) and a benzoyl group or two coinitiators to the phenolic and carboxyl group position of erythrosine B. The combination of the iodonium salt and free tertiary amino used to initiate the free-radical/cationic visible photopolymerization was investigated to acquire the relationship between the structure and performance. The photoinitiating ability of the derivative with the phenolic position bearing a coinitiator was poorer than of the derivative with the carboxyl group bearing one because of the strong back electron transfer of the former. For the derivative with a linked coinitiator on the carboxyl position, the proximity effect between the sensitizer and the coinitiator moiety resulted in an excellent photoinitiating ability for radical/cationic polymerization; this suggested its potential for application. Although radical/cationic photopolymerization could be initiated by the derivative/coinitiator/iodonium salt, the different component ratios between them had different effects on these two polymerizations; this provided useful information for the design of effective photoinitiators for different polymerizations. On the basis of the fluorescence quenching and photopolymerization results, a corresponding synergistic mechanism was proposed. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133 , 43035.
研究领域:
高分子科学
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材料化学
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光化学
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产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2012
·Vol. 128
·期 1
·89-96
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IF 1.289
Qunfang Wang,Li Ren,Caixia Xu,Zhichen Zhai,Jia-an Zhou,Yongchang Yao,Huan Xia,Yingjun Wang
This study presented the synthesis and characterization of glucosamine (GlcN) modified poly (ethylene glycol) (PEG) hydrogels. The chemical structure was characterized by Fourier transform infrared (FTIR) and proton nuclear magnetic resonance ( 1 H NMR) spectroscopy. The morphology of hydrogels was observed by scanning electron microscopy (SEM). The results indicated that GlcN was successfully incorporated into PEG hydrogel network. Moreover, the data of the swelling ratio showed that the ratio of GlcN-modified PEG hydrogels was lower than that of pure poly(ethylene glycol) diacrylated (PEGDA). Biocompatibility of unreacted GlcN monomer and GlcN-modified hydrogels was also evaluated in vitro . Compared with glucosamine hydrochloride, 2 and 5 m M N -acroloyl-glucosamine monomer exhibited no toxicity against bone marrow stromal cells (BMSCs), while with the concentration increased to 10 m M , cell viability appeared to decrease. However, when BMSCs were encapsulated in GlcN-modified hydrogels via photopolymerization method, cells remained vigorous viability. Metabolic activity of the encapsulated cells demonstrated GlcN-modified hydrogels was favorable for cell proliferation. Compared with free GlcN, covalent binding GlcN showed lower cytotoxicity and higher cell proliferation properties. As a result, GlcN-modified PEGDA hydrogels could be used as safe and injectable cell carriers for in situ tissue engineering applications. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
研究领域:
生物材料
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组织工程
·
医学
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DOI
高影响因子
ACS Sensors
·
2018
·
IF 5.711
Jieyao Song,Hongjian Zhou,Rui Gao,Yong Zhang,Haimin Zhang,Yunxia Zhang,Guozhong Wang,Po Keung Wong,Huijun Zhao
Selective determination of aquatic chromium is critically important because of the dramatic differences in health and environment impacts by trivalent and hexavalent forms of chromium; however, it is challenging. In this work, for the first time, a nonconjugated polymer fluorophore (GCPF) was synthesized by cross-linking chitosan with glutaraldehyde via Schiff base reactions and systematically investigated for selective determination of Cr(VI). The results revealed that the synthesized GCPF exhibited excellent photostability and water solubility. More importantly, GCPF possessed dramatically enhanced fluorescence intensity originated from the n−π* transitions of the Schiff base subfluorophore groups (e.g., C═N) that can be selectively and sensitively quenched by Cr(VI) through oxidative damages to C═N group. An effective EDTA masking agent approach was employed to minimize ionic interferences. In the presence of high concentration of interference ions including Cr(III), the quenching GCPF fluorescence is capable of selectively determining Cr(VI) within a concentration range up to 50 μM and a detection limit of 0.22 μM. The analytical performance of GCPF was also confirmed by analyzing real surface water and industrial samples.
研究领域:
环境科学
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分析化学
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材料科学
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DOI
高影响因子
POLYMER
·
2021
·
IF 4.43
Zhengyuan Zhang,Hongyu Yan,Zejun Yin,Yuechuan Wang
The acetylene functional groups on polymer chains provide a photochemical access to modulate or actuate the properties of the polymer. We report here a photochemical way to actuate a polyacrylate to elastomers . High molecular weight acetylene functionalized homo- and copolymers of are prepared with a novel monomer , 2-(dimethylpropargyloxy)ethyl methacrylate , DMPOEMA, by photo-initiated free-radical polymerization (FRP) in solution at room temperature . The acetylene groups are tolerant of the solution photo FRP at 50 wt% concentration, but not tolerant to thermal FRP and photo FRP at 80 wt% concentration. Copolymers P(DMPOEMA- co -EA) with‾M n in 12,500–15,100 g/mol were prepared with conversion up to 90% at 50% concentration and three monomer feed ratios. The feed ratio of DMPOEMA had slight effects on the polymerization rate, but effects on PDI at higher monomer conversion with prolonged photo-irradiation. The acetylene functionalized polyacrylates become photo-sensitive and are photo cross-linkable or photo clickable after solvent is removed. Real-time FT-IR study reveals that the photo cross-linking with a tri-thiol compound follows the normal thiol-yne photochemistry , and the photo cross-linking catalyzed with only photoinitiator results in diene units in the cross-linked polymer networks . These photo-treated polyacrylate exhibited designable elastomer properties: with T g in −24 to −11 °C, more than 10 times increase of relative cross-linking density and resistant to solvents, improved stress, strain and elongation properties. This work paves a way for the acetylene functionalized (meth)acrylates as advanced photo-reactive material.
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
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Jun Xiao,Dongqing Liu,Haifeng Cheng,Yan Jia,Shen Zhou,Mei Zu
As a new method for producing dense ceramics with complex structures, digital light processing 3D printing technology has received considerable attention when applied to polymer-derived ceramics. In this study, using acrylate monomers, we developed a material system to modify the polysilazane preceramic polymers. Furthermore, during photopolymerization , the photocuring thickness was tuned using carbon nanotubes as light absorbers, thus improving the printing accuracy. The green body was printed and subsequently pyrolyzed to obtain the SiCN ceramic. We then managed to completely maintain the printed structure with uniform shrinkage being observed in all directions. The printed ceramic microstructures, denoting pyrolysis-induced microstructural changes, were characterized using scanning electron microscopy, X-ray diffraction, and transmission electron microscopy . This study paves the way for developing new approaches to obtain ultra-light and high-strength microwave-absorbing components that are suitable for aerospace applications by combining the SiCN ceramics of the unique dielectric properties with 3D printing technology to produce dense ceramics with periodic 3D structures.
研究领域:
材料科学
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陶瓷工程
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产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2018
·
IF 5.158
Yongjun Sun,Wenquan Sun,Kinjal J. Shah,Pen-Chi Chiang,Huaili Zheng
In this work, carboxylated chitosan modified flocculant (CC-g-PCD) was prepared by graft copolymerization technique to enhance the charge-attracting and adhesion of bridges and net-sweeping capacity of flocculants. The dimethyldiallylammonium chloride (DMDAAC), carboxylated chitosan (CMCS), and 3-chloro-2-chloropropyltrimethylammonium chloride (CTA) were utilized for synthesis of CC-g-PCD via photopolymerization techniques. The synthesized CC-g-PCD was characterized by 1 H NMR, SEM, XRD, and FTIR, and the characteristic groups on the main chain and surface morphological structure of CC-g-PCD were investigated. The obtained results indicated that CTA and DMDAAC were successfully grafted into the CPCTS. In ordered to evaluate the flocculation performance of CC-g-PCD at various dosages, stirring intensity (G value), and pH value by detecting Chl a, COD, and turbidity, the actual lake water that contains algae was used for flocculation assessment tests. The experimental results of the water sample with flocculation showed that the maximum flocculation efficiency of turbidity (91.1%), Chl a (97.2%), and COD (97.0%) can be achieved by CC-g-PCD at pH 7, G value 200 s −1 , and 4.0 mg/L. The comparison results demonstrated that CC-g-PCD had better flocculation efficiency than commercial flocculants. Finally, based on the analysis of algae removal in combination with Zeta potential measurements, the flocculation mechanisms in actual lake water at various dosages and pH values were adsorption bridging and electrical neutralization.
研究领域:
环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）