ACS Applied Engineering Materials
·
2024
·
IF 0
Yan Liao,Jian Li,Chenyi Wang,Qiang Ren
Poly(3,4-ethylenedioxythiophene):poly(sodium styrenesulfonate) (PEDOT:PSS) is widely used in many aspects due to its good electrical conductivity. However, the low solid content of the PEDOT:PSS aqueous dispersion hinders its further application. Aiming to address this problem, a kind of novel “long-armed” crosslinked microspheres (cPBA@PSS), with crosslinked poly(butyl acrylate) as the core and poly(sodium styrenesulfonate) as the “long arm”, is synthesized via reversible addition–fragmentation chain transfer (RAFT) soap-free emulsion polymerization. With the “long-armed” crosslinked microspheres as the template, poly(3,4-ethylenedioxythiophene):poly(butyl acrylate-co-sodium styrenesulfonate) (PEDOT:cPBA@PSS) with a high solid content and low viscosity is successfully fabricated. The structures of cPBA@PSS are confirmed by infrared spectroscopy and hydrogen nuclear magnetic resonance spectroscopy. A PEDOT:cPBA@PSS aqueous dispersion with a solid content as high as 25 wt % is obtained by using long-armed crosslinked microspheres as the template due to the reduction of the entanglement between macromolecules. The kinetic study shows that the solid content of the dispersion has little effect on the polymerization rate of 3,4-ethylenedioxythiophene (EDOT). However, the viscosity of PEDOT:cPBA@PSS aqueous dispersions increases with an increase in the solid content. A PEDOT:cPBA@PSS aqueous dispersion with a solid content of up to 25 wt % shows a viscosity of about 37 mPa·s. The effect of the solid content on the transparency of PEDOT:cPBA@PSS films is studied, and no significant impact on film transparency is observed. The transmittance of the films at 550 nm is over 80%. The conductivity of the PEDOT:cPBA@PSS film increases with an increase in the solid content of the dispersion. The PEDOT:cPBA@PSS aqueous dispersion with a solid content of 25 wt % shows a conductivity of 0.68 S/cm when the ratio of PEDOT to cPBA@PSS is 1:1. The conductivity of the PEDOT:cPBA@PSS film can also be enhanced by secondary doping of dimethyl sulfoxide (DMSO), and the conductivity of the PEDOT:cPBA@PSS film can be increased to about 3.82 S/cm. This study shows that the use of the long-armed crosslinked microsphere cPBA@PSS as a template is an effective method to fabricate PEDOT aqueous dispersions with a high solid content and low viscosity.
研究领域:
材料科学
·
高分子化学
·
电化学
✓ 已验证
DOI
JOURNAL OF APPLIED POLYMER SCIENCE
·
2014
·Vol. 131
·期 12
·
IF 1.64
ShaoJun Peng,Yong Jin,Tongbing Sun,Rui Qi,BaoZhu Fan,XinFeng Cheng
A series of waterborne polyurethane dispersions were synthesized by one-pot reaction and step-wise reaction, respectively. The effects of synthetic methods and DMPA content on the particle size distribution (PSD), solid contents and viscosity were studied by laser particle size analyzer, Brookfield viscometer and TEM analysis. High solid content and low viscosity waterborne polyurethanes (WPUs) with controllable bimodal PSD were prepared by one-pot reaction using 2,2-dimethylol propionic acid (DMPA) as the only self-emulsifier. Meanwhile, 40% solid content WPUs with unimodal PSD were obtained by step-wise reaction at the same formula. With the increment of DMPA content, the ratio of large particles to small particles decreased and two peaks of the particle size finally became one peak by one-pot reaction while the PSD remained unimodal by step-wise reaction. The reason leading to the difference of PSD between one-pot reaction and step-wise reaction was analyzed and the relationships among PSD, viscosity and solid content were discussed. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131 , 40420.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
Journal of Manufacturing Processes
·
2021
·
IF 5.01
He Li,Yongsheng Liu,Yansong Liu,Qingfeng Zeng,Jingjing Liang
Stereolithography based-3D printing technology requires ceramic slurries with high solid content and low viscosity to prevent the formation of cracks, holes, warping, and other defects in sintered ceramic parts. In this study, several approaches based on optimization of alumina powder and coupling agent were explored to improve the solid content of ceramic slurries. It was shown that slurries containing γ-Al 2 O 3 reached solid content of only 22.5 wt% and viscosity of 15,199 mPa·s. By comparison, slurries composed of α-Al 2 O 3 reached higher solid content of 75 wt% and viscosity of 12,780 mPa·s. Three types of coupling agents, namely (3-Aminopropyl) triethoxysilane, (Aminoethylamino) propyldimethoxymethylsilane and 3-(Trimethoxysilyl) propyl methacrylate (abbreviated as E, F and G, respectively) were used to reduce the viscosity of the slurries. The addition of 10 wt% G led to slurry solid content reaching 82 wt% and viscosity of 860 m·Pas. The significant decrease in viscosity was mainly attributed to the presence of bifunctional hydrolyzable groups in G, which could well attach to alumina. On the other hand, the presence of organo-functional groups might also well attach to the photosensitive resin. The ceramics prepared with γ-Al 2 O 3 exhibited numerous pores in both intraparticle and intergranular while those obtained with α-Al 2 O 3 showed pores in only intergranular. The porous structure in γ-Al 2 O 3 occupied large space, leading to low solid content. Ceramics prepared with 75 wt% solid content possessed flexural strength of 29.3 MPa, bulk density of 2.3 g/cm 3 and open porosity of 39.8 %. By comparison, ceramics prepared with 82 % solid content showed flexural strength of 45.0 MPa. In sum, these findings look promising for future preparation of high-solid content 3D printed ceramic slurries for complex ceramics, such as ceramic cores.
研究领域:
材料科学
·
3D打印技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POLYMER RESEARCH
·
2023
·Vol. 30
·期 7
·1-10
·
IF 2.8
Yao Aisong,Li Heng,Luo Haihang,Zhao Jianming,Xiang Jun,Chen Yi,Fan Haojun
Eethylenediamine (EDA), isophorone diamine (IPDA), diethylenetriamine (DETA), N- β- (aminoethyl)- γ- aminopropylmethyl dimethoxysilane (KH602) and polyether amine (D-230) were used as post chain extenders, a series of solvent-free high-solid content water-based polyurethanes (WPU) were prepared. The reactivity of different post chain extenders and the effects of different R values (mole ratio of –NCO/-OH) on solid content as well as the effects of chain extension degree on properties of WPU were investigated in detail. Among of water, small molecule diamine and diol, diamine with higher activity is preferred to water to complete the post chain extension reaction and improves the mechanical properties of WPU. When the R value is higher than 1.7 and the post chain extension degree is controlled at 70%, the viscosity of the solvent-free prepolymer is small enough to be emulsified, and the as-prepared WPUs show more excellent thermodynamic properties. In comparison, the cyclic chain extender such as IPDA can improve the mechanical properties and heat resistance of WPU, crosslinking type chain extenders involving DETA and KH602 can improve the heat resistance and anti-sticking of WPU coating. Whilst the WPU prepared by the chain extender containing flexible space, such as D-230, has a very low modulus and is suitable for preparing soft–type WPU.
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
COMPOSITES SCIENCE AND TECHNOLOGY
·
2022
·
IF 9.879
Longxuan Gao,Fei Yan,Shengtao Dai,Lianshuang Zhao,Junming Wang,Yu Liu,Yuhui Ao,Liu Liu
To improve the unsatisfactory interfacial adhesion of carbon fiber/polyamide-6 (CF/PA6) composites, a hyperbranched waterborne polyurethane (HWPU) sizing agent with high-solid content was designed. As a carboxy chain extender for HWPU, carbic anhydride-tris(hydroxymethyl)methyl aminomethane (CA-THAM) with a self-catalytic capacity was synthesized to accelerate the chain extension. The synthesized hyperbranched polyurethane exhibited low viscosity, along with a strong double-electron layer conformation after dispersing in water. The electrostatic repulsion between the latex particles effectively prevented agglomeration, delivering a high solid content of 58% for the sizing agent. The influence of different sizing agent concentrations on the wettability of CF as well as the interfacial properties of composites was systematically studied. Compared with unsized CF/PA6 composites, the interlaminar shear strength and flexural strength of CF-1.5 wt%/PA6 composites were up to 60.3 MPa and 508.4 MPa, with an increment of 50.3% and 27.7%, respectively. Furthermore, the interfacial strengthening mechanism of sizing agent was discussed. The preparation of this high-solid content sizing agents was facile and environmentally friendly, which would hopefully reduce costs during the transportation.
研究领域:
材料科学
·
复合材料工程
✓ 已验证
DOI
高影响因子
ADVANCED ENGINEERING MATERIALS
·
2019
·Vol. 22
·期 3
·1900911
·
IF 2.906
Guangbin Shao,Henry Oliver T. Ware,Longqiu Li,Cheng Sun
The capability of fabricating magnetically active 3D microstructures is crucial for miniaturization of microrobots or microactuators. While additive manufacturing using magnetic nanoparticle-infused polymer resin offers the highly desirable precision and flexibility, the difficulty in handling resin with higher solid loading of magnetic nanoparticles needed to maximize the magnetic actuation forces remains to be the main obstacle. The increased viscosity of the magnetic resin not only significantly reduces the fabrication speed, but also makes the process vulnerable to the precipitation of the suspended magnetic nanoparticles. Herein, a comprehensive solution that synergizes the optimization of magnetic photopolymerizable resin and the high-speed 3D printing using microcontinuous liquid interface production (μCLIP) process is reported. An optimized magnetic photopolymerizable resin with 30 wt% solid loading of Fe 3 O 4 nanoparticles is well dispersed over 72 h. Process characteristics of the magnetic photopolymerizable resins with variation in the solid loading of magnetic nanoparticles are investigated experimentally. The capability of 3D printing centimeter-size samples with sub-75 μm fine features using high solid loading (30 wt%) is also demonstrated. The increased printing speed using μCLIP significantly reduces the fabrication time to the order of minutes to hours, making the process more robust against the precipitation of the magnetic particles.
研究领域:
材料科学
·
机器人学
·
制造工程
✓ 已验证
DOI
高影响因子
Journal of Applied Research on Medicinal and Aromatic Plants
·
2021
·
IF 3.4
Jintong Zhang,Lan Wang,Hongzhang Chen
Artemisinin extracted at low solid loading causes low product concentration and high organic solvent usage. In this study, extraction in high solids of Artemisia annua by periodic peristalsis was proposed to increase the concentration of artemisinin and improve the extraction efficiency. The results showed that the artemisinin yield, extracted from leaves of Artemisia annua , increased by 33.9 %–46.5 % in periodic peristalsis extraction (PPE) compared with hot maceration extraction (HME). Based on the lower T2 relaxation time and the higher peak height of pools of solvent, periodic peristalsis could enhance solvent penetration effectively in porous media. Additionally, since the properties of capillary solvent were highly related to the diffusion coefficient (Pearson correlation coefficient > 0.98), periodic peristalsis improved the diffusion coefficient mainly by promoting the penetration of capillary solvent, which resulted in an increase in high solids extraction efficiency. Therefore, periodic peristalsis treatment could be an effective technology to improve natural product extraction performance in high solids.
研究领域:
植物学
·
药用植物研究
·
提取技术
✓ 已验证
产品关联
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2015
·
IF 2.358
Shao-Jun Peng,Yong Jin,Xin-Feng Cheng,Tong-Bing Sun,Rui Qi,Bao-Zhu Fan
A new method named two-step emulsification process was developed to synthesize high solid content waterborne polyurethanes by strict control of the bimodal particle size distribution. In the first step, a series of 40% solid content polyester-based (WPU-1) with low content of hydrophilic group and large particle size were firstly synthesized. In the second step, polyether-based prepolymers (WPU-2 prepolymers) with high content of hydrophilic group were firstly prepared and WPU-1 emulsions were used to emulsify WPU-2 prepolymers to obtain the final emulsions with high solid content (WPU-3). The particle size of WPU-3 present bimodal distribution and the diameter ratio and volume percentage of large particles to small particles in WPU-3 were able to be strictly controlled by this method. The viscosity of WPU-3 with 55% solid content was only 489.1 mPa s −1 when the diameter ratio of large particles to small particles was 9.2 and the volume percentage of large particles was 74%.
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
ACS Sustainable Chemistry & Engineering
·
2017
·
IF 5.951
Weiliang Hou,Lang Li,Jie Bao
High product concentration in aerobic biorefining fermentation requires high lignocellulose feedstock loading. However, the high solids content and the consequent high viscosity of the lignocellulose hydrolysate severely limit oxygen transfer and thus lead to low aerobic fermentation rate. This study first investigates the experimental measurement and the computational fluid dynamics (CFD)-based simulation of oxygen transfer properties in the high solids loading and highly viscous lignocellulose hydrolysates. The oxygen mass transfer coefficients kLa values vary with various biorefining processing parameters. A minimum threshold kLa value was required for aerobic fermentation of glucose oxidation into gluconic acid. The rheological properties of the slurry were experimentally determined, and a CFD model was established for the design of aerobic fermentation bioreactors. The kLa values between the CFD calculation and the experimental determination were in good agreement for the high solids loading and highly viscous hydrolysate slurry. The study provided important information and useful tools for achieving efficient aerobic fermentations in high solids loading and highly viscous lignocellulose hydrolysates. The measured kLa value could be applied to general aerobic fermentation using lignocellulose feedstock.
研究领域:
生物工程
·
发酵工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Chun Chang,Shijie Wang,Pengkun Guo,Guizhuan Xu,Xiaoyang Zheng,Chaojun Du,Youzhou Jiao
Increasing efforts have been devoted to the production of bio-based chemicals from high solid content of renewable biomass to pursue optimal process efficiency and economics. In this study, the preparation of methyl levulinate (ML) by metal sulfate-catalyzed methanolysis from high solid content of cellulose was investigated. When the cellulose loading was 15%, 38.67% of ML yield can be obtained under the optimum reaction conditions. Al 2 (SO 4 ) 3 can be reused more than five times while maintaining high activity in the process. The characterization of cellulose particles confirmed that cellulose particles shrunk over the reaction time. The heterogeneous degradation kinetics of high solid content of cellulose in methanol could be explained by a shrinking core model. High solid loadings led to a decrease of the reaction rate constants of methanolysis. Using cellulose with a small particle size can improve the methanolysis reaction rate. The study also proposed comprehensive reaction pathways for ML production from high solid content of cellulose. To elucidate the methanolysis mechanism, an assessment of density functional theories for the calculation of glucose methanolysis at the molecular level is presented. All these results can inspire the development of ML synthesis technology through methanolysis from renewable biomass with high solid loadings.
研究领域:
生物化学
·
可再生资源工程
✓ 已验证
产品关联
DOI
高影响因子
BIOPROCESS AND BIOSYSTEMS ENGINEERING
·
2018
·Vol. 41
·期 8
·1153-1163
·
IF 2.139
Du Jian,Song Wenxia,Zhang Xiu,Zhao Jian,Liu Guodong,Qu Yinbo
High dosage of enzyme is required to achieve effective lignocellulose hydrolysis, especially at high-solid loadings, which is a significant barrier to large-scale bioconversion of lignocellulose. Here, we screened four chemical additives and three accessory proteins for their effects on the enzymatic hydrolysis of various lignocellulosic materials. The effects were found to be highly dependent on the composition and solid loadings of substrates. For xylan-extracted lignin-rich corncob residue, the enhancing effect of PEG 6000 was most pronounced and negligibly affected by solid content, which reduced more than half of enzyme demand at 20% dry matter (DM). Lytic polysaccharide monooxygenase enhanced the hydrolysis of ammonium sulfite wheat straw pulp, and its addition reduced about half of protein demand at the solid loading of 20% DM. Supplementation of the additives in the hydrolysis of pure cellulose and complex lignocellulosic materials revealed that their effects are tightly linked to pretreatment strategies.
研究领域:
生物化学
·
可再生资源与环境工程
✓ 已验证
DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
·
2019
·
IF 6.669
Jian Du,Jingrui Liang,Xiuhua Gao,Guodong Liu,Yinbo Qu
Optimization of the composition of cellulase mixtures is an effective strategy to improve their hydrolytic efficiency and reduce protein demand during enzymatic degradation of lignocelluloses. In this study, the mixture design method was used to optimize the ratios of endoglucanase II (EG II), cellobiohydrolase I (CBH I) and β-glucosidase I (BG I) from Penicillium oxalicum in an artificial cellulase mixture for the hydrolysis of six different cellulosic materials. The optimal composition of enzyme mixture was distinctly different among not only cellulosic materials with different pretreatment methods but hydrolyses at different solids concentrations. CBH I was most critical for the hydrolysis of two acid-pretreated materials, probably due to its strong adsorption on lignin. A higher proportion of EG II was needed for the hydrolysis of ammonium sulfite pretreated wheat straw. The requirements of specific cellulase components were more pronounced at high solids concentrations, highlighting the importance of considering solids loading when optimizing cellulase cocktails.
研究领域:
生物技术
·
酶学
✓ 已验证
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）