JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 7
·49831
·
IF 2.52
Tao Li,Weilin Wang,Songmeng Wang,Lingyan Liu,Weixing Chang,Jing Li
An amphiphilic block copolymer PNIPAM 53 - b -(PS 30 - co -P4AMS 10 ) was facilely prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization. The immobilization of ( S )-α,α-diphenylprolinol trimethylsilyl ether onto the block copolymers was then performed through using copper-catalyzed alkyne-azide cycloaddition (CuAAC), and the generating amphiphilic diblock copolymer supported chiral catalyst PNIPAM 53 - b -(PS 30 - co -P4AMS 10 )/proTMS was self-assembled into micelles with regular diameters about 50 nm in aqueous solution. The micellar catalyst was further used for the asymmetric Michael reaction between propanal and trans -β-nitrostyrene in water. Using only 1 mol% micellar catalyst, the corresponding Michael addition products could be obtained in good yields and high enantioselectivities as well as good diastereoselectivities. In addition, this micellar catalyst could be reused at least for four times. Moreover, the micellar catalyst could be applied for the asymmetric addition reaction of 4-chlorocinnamyl aldehyde and nitromethane, and thus constructing the baclofen pharmaceutical intermediate.
研究领域:
高分子化学
·
有机合成
·
催化化学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2014
·Vol. 131
·期 22
·
IF 1.64
Yanyan Zhang,Hong Fan,Bo-Geng Li
Advance polyamide-6- b -polydimethylsiloxane (PA6- b -PDMS) multiblock copolymers were first synthesized via the polymerization in bulk. Binary carboxyl terminated PA6 was served as the hard segment and PDMS modified with hexamethylene diisocyanate (PDMS-NCO) was the soft segment. A series of PA6 -b- PDMS copolymers based on different content and length of soft segments were obtained. Interestingly, Differential scanning calorimetry (DSC) studies revealed no obvious change in melting temperature after introducing PDMS segments to copolymers. The high melting temperatures indicated these copolymers possess potential applications in automotive industry that require high continuous use temperatures. DSC and transmission electron microscopy studies both demonstrated increasing the length and the content of the soft segment contributed to increasing of the degree of microphase separation. However, the improvement of thermal stability resulting from PDMS segments was also observed by thermo gravimetric analysis. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131 , 41114.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2013
·Vol. 131
·期 6
·
IF 1.395
Alsamani A. M. Salih,Chunhai Yi,Jiayang Hu,Lijuan Yin,Bolun Yang
A vinyl amine–vinyl alcohol copolymer (VAm–VOH) was synthesized through free-radical polymerization, basic hydrolysis in methanol, acidic hydrolysis in water, and an anion-exchange process. In the copolymer, the primary amino groups on the VAm segment acted as the carrier for CO 2 -facilitated transport, and the vinyl alcohol segment was used to reduce the crystallinity and increase the gas permeance. VAm–VOH/polysulfone (PS) composite membranes for CO 2 separation were prepared with the VAm–VOH copolymer as a selective layer and PS ultrafiltration membrane as a support. The membrane gas permselectivity was investigated with CO 2 , N 2 , and CH 4 pure gases and their binary mixtures. The results show that the CO 2 transport obeyed the facilitated transport mechanism, whereas N 2 and CH 4 followed the solution–diffusion mechanism. The increase in the VAm fraction in the copolymer resulted in a carrier content increase, a crystallinity increase, and intermolecular hydrogen-bond formation. Because of these factors, the CO 2 permeance and CO 2 /N 2 selectivity had maxima with the VAm fraction. At an optimum applied pressure of 0.14 MPa and at an optimum VAm fraction of 54.8%, the highest CO 2 permeance of 189.4 GPU [1 GPU = 1 × 10 −6 cm 3 (STP) cm −2 s −1 cmHg −1 ] and a CO 2 /N 2 selectivity of 58.9 were obtained for the CO 2 /N 2 mixture. The heat treatment was used to improve the CO 2 /N 2 selectivity. At an applied pressure of 0.8–0.92 MPa, the membrane heat-treated under 100°C possessed a CO 2 permeance of 82 GPU and a CO 2 /N 2 selectivity of 60.4, whereas the non-heat-treated membrane exhibited a CO 2 permeance of 111 GPU and a CO 2 /N 2 selectivity of 45. After heat treatment, the CO 2 /N 2 selectivity increased obviously, whereas the CO 2 permeance decreased. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014 , 131 , 40043.
研究领域:
材料科学
·
环境工程
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2018
·Vol. 135
·期 23
·4634159
·
IF 1.901
Sheng Zhou,Xiaolu Wang,Wei Zhang,Mengyao Zhang,Xiaoli Zhang,Ning Zhao,Ruigang Liu,Jian Xu,Zhihao Shen,Xinghe Fan
It remains a problem to prepare cost-effective aramid with good solubility via a simple method since the commercialization of aromatic polyamides such as Kevlar and Nomex by DuPont in 1960s. Herein, we report the facile preparation and properties of an aromatic polyamide copolymerized by 2,6-naphthalene dichloride (26N-COCl), 4,4′-oxydianiline, and m -phenylenediamine. The synthetic route is very facile and cost-effective. The modified aramids possess excellent comprehensive properties. The polymers are soluble in some organics. Their thermal stabilities are excellent, with 5% weight loss temperatures ( T d ,5% 's) in air higher than 460 °C and glass transition temperatures ( T g 's) higher than 280 °C. These polymers are easily processed into films, fibers, and tubes. The products exhibit high strength. For example, the films have excellent mechanical strength, with a tensile strength up to 139 MPa, a tensile modulus up to 3.45 GPa, and an elongation of 11%. The films are also transparent and fluorescent. The overall properties are better than those of the commercial Nomex. The facilely prepared aramids with good solubility are very promising for commercial use. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135 , 46341.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2024
·Vol. 142
·期 5
·e56438
·
IF 2.7
Jiawei Hai,Chuang Zhan,Xunwei Chen,Biwei Qiu
This study explores how acid type (hydrochloric acid [HCl], p-toluenesulfonic acid [TSA], and formic acid [FA]) and concentration affect the structure of polyaniline (PANI) and the electrochemical properties of its composite with vertically aligned single-walled carbon nanotubes (SWCNTs). PANI doped with TSA (PANI-TSA) exhibited improved dispersion and conjugation attributed to the larger anion volume, which mitigates interchain spacing, in contrast to PANI doped with HCl (PANI-HCl) and FA (PANI-FA). Additionally, varying the organic acid concentration affected PANI's morphology and the concentration of quinone structure, with TSA leading to a fibrous structure and enhanced electrochemical characteristics. The study further investigated the SWCNTs/PANI composite, revealing that higher TSA concentrations enhance conductivity and specific capacitance of the composite membrane due to sulfonic acid group. Notably, HCl-based SWCNTs/PANI only at higher acid concentrations exhibits superior electrochemical characteristics than TSA-based SWCNTs/PANI, achieving charge transfer resistance down to 5.514 Ω cm 2 at 1.0 mol/L. Moreover, applying an electric field during membrane synthesis significantly increased the specific capacitance of composite prepared with PANI-TSA, highlighting the role of voltage in optimizing electron transport efficiency within the composite.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2019
·Vol. 137
·期 8
·48405
·
IF 2.188
Qing Wen,Lijuan Xu,Xiansen Xiao,Zhenghui Wang
Cationic nanopolystyrenes (CNPSs) were prepared by the polymerization of styrene with a cationic polymerizable emulsifier, N-(2-(methacryloyloxy)ethyl)-N,N-dimethyltetradecane-1-ammonium bromide (MDTB), in the presence of 2,2′-azobis(2-methylpropionamidine) dihydrochloride (APPH). The polymerization kinetics was investigated through monomer conversion versus polymerization time. 1 H NMR spectra and FTIR spectra were used to confirm the structures of MDTB and nanopolymers. The particle size, ζ-potential, molecular weight, and thermal stability were also investigated by Zetasizer, gel permeation chromatography, and thermogravimetric analysis, respectively. The antibacterial activities of the obtained products were evaluated by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against Staphylococcus aureus ATCC 29913 ( S. aureus , a Gram-positive bacterium) and Escherichia coli ATCC 25922 ( E. coli , a Gram-negative bacterium). The results indicated that the polymerization has the characteristics of microemulsion polymerization, all nanopolystyrenes are cationic and can be stored in the form of a microemulsion in aqueous phase, CNPSs present stable chemical structure at 190 °C, and their MIC and MBC reach 0.0625 and 0.125 mg mL −1 for E. coli , 0.0325 and 0.0625 mg mL −1 for S. aureus , respectively. Therefore, CNPSs are a promising new type of polymer antimicrobial agent, which can be used in the development of antimicrobial polymer materials and their products. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137 , 48405.
研究领域:
高分子化学
·
材料科学
·
微生物学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 139
·期 18
·52075
·
IF 3.125
Bihua Xia,Xuhui Zhang,Yang Wang,Ting Li,Jie Jiang,Mingqing Chen,Tianxi Liu,Weifu Dong
This paper reported a new kind of multilayer cross-linking polyetherimide/Ti 3 C 2 T x MXenes material with pores channel structure for electromagnetic interference shielding. Polyetherimide was used as the resin material, ethylenediamine (EDA) was used as the cross-linking agent, special multilayer and pores channel were used as the shielding structure, and Ti 3 C 2 T x MXenes was used as the electromagnetic wave shielding medium. By adjusting the content of EDA, the cell structure, electromagnetic interference shielding efficiency, and tensile strength of multilayer cross-linking PEI/Ti 3 C 2 T x MXenes shielding material could be controlled. The more EDA content, the higher cross-linking degree, the smaller the cellular size, the higher the electromagnetic interference shielding efficiency, and the stronger the tensile strength.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 139
·期 15
·51943
·
IF 3.125
Xuejun Zhou,Jiyou Zong,Jun Lei,Zhongming Li
In this work, a series of spherical boron nitride/silicone rubber (sBN/SR) composites were prepared, and the influence of different shapes and sizes of BN on the thermal conductivities of the composites was investigated. Additionally, hybrid spherical boron nitride/silicon rubber (hybrid sBN/SR) composites were fabricated by synchronously incorporating two kinds of sBN particles into SR to perfect the thermal conduction paths, and a synergistic effect of the fillers was achieved. The thermal conductivity of the composite could reach 1.70 W/(m·K) at the 35 wt% filler content, which is clearly superior to the composite containing single type of filler and stands at a very high level at such a filler fraction according to the reported literature. Also, the experimental results were supported by the Agari's equation. In addition, the composites show a low hardness (shore A hardness < 60) due to the low filling content. The prepared materials hold great promise in thermal interface materials for thermal management of state-of-the-art electronic equipment.
研究领域:
材料科学
·
热传导工程
·
电子材料
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2019
·Vol. 137
·期 24
·48803
·
IF 2.188
Yang Xu,Ying Xiong,Shaoyun Guo
In this work, poly( ε -caprolactone) (PCL) and liquid plasticizer were combined used to plasticize poly(vinyl chloride) (PVC), and the possibility of using PVC/PCL/plasticizer blends to fabricate soft PVC with enhanced migration resistance was investigated. Through partial replacement of liquid plasticizers in soft PVC by equal quantity of PCL, flexibility was maintained while extraction loss of plasticizer by organic solvent was reduced significantly. Furthermore, crystallization of PCL in PVC/PCL/plasticizer blends with low PCL content was observed, and crystallization rate of PCL was found to be influenced by plasticizer contents and structures. For instance, crystallization rate of PCL in PVC/PCL/diisononyl phthalate (DINP) (100/40/100) was 3.7 times faster than in PVC/PCL/DINP (100/40/80), while crystallization rate of PCL in PVC/PCL/dioctyl adipate(DOA)(100/40/100) was 8.3 times faster than in PVC/PCL/diisononyl cyclohexane-1,2-dicarboxylate (DINCH) (100/40/100). Low-field 1 H NMR test manifested that different crystallization rate of PCL in PVC/PCL/plasticizer blends with different plasticizer structures was triggered by difference in plasticizers' compatibility with PVC, that is, the number of interaction point between PVC and plasticizers. It is concluded that PCL crystallization favored by liquid plasticizers in PVC/PCL/plasticizer blends was induced by interaction competition between PVC/plasticizer and PVC/PCL. As plasticizer content increases or its compatibility with PVC decreases, interaction competition becomes more intense and consequently faster crystallization of PCL occurs. Thus, to obtain soft PVC products with improve migration resistance while avoiding PCL crystallization, the total content of plasticizer (including both liquid plasticizer and PCL) should be lower than 66 phr (40 wt %). © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137 , 48803.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 137
·期 36
·49081
·
IF 2.52
Huan Yu,Haiyan Liu,Xiaoya Pang,Miaomiao Zhang,Hongyuan Yan,Ligai Bai
In this study, a composite poly(functional graphene oxide- co - N -isopropylacrylamide- co -trimethylolpropane triacrylate- co -ethylene dimethacrylate) (poly(f-GO- co -NIPAAm- co -TMPTA- co -EDMA)) monolith was prepared, in which f-GO was added. The obtained monolith was characterized by nitrogen adsorption–desorption isotherm and scanning electron microscopy. The monolith exhibited a homogeneous and continuous structure, good permeability, and large surface area. The composite monolith was used as solid-phase extraction absorbent in conjunction with high-performance liquid chromatography for enrichment of ursolic acid. The calibration equation was y = 73.3980 x + 0.2555, and the linear regression coefficient was 0.9987; The calibration curve was ranged from 1 to 700 μg ml −1 ; The limit of detection and limit of quantification values were 0.3 and 1.0 μg ml −1 , respectively; The intraday and interday precisions were less than 2.6 and 7.4%, respectively. The recovery was in the range of 84.44–111.76%. Moreover, the adsorption amount of ursolic acid on the composite monolith was compared with the monolith without f-GO added and silica gel-C18 adsorbent. The results showed that the composite monolithic column was feasible to be used as an online SPE absorbent, which exhibiting low back pressure, good permeability, and high adsorption capacity. In addition, this method provided the possibility to extract and analyze trace components from medicinal plants.
研究领域:
分析化学
·
药学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 137
·期 34
·48982
·
IF 2.52
Jian Yang,Tong Zhang,Yue Yin,Wenhong Jiang,Yunzhe Du,Xiaofei Zhu,Bo Jiang,Yudong Huang
Reactive group content was a key parameter in polymer curing process. However, the conventional methods to measure the curing were destructive and time consuming. In this article, near-infrared spectra technology had been applied for reactive group analysis of the photothermal curing silicone to achieve rapid nondestructive and quantitative detection. The calibration model was developed about epoxy value and CC double bond value, with determination coefficient ( R 2 ) of 0.9631 and 0.9689. Root mean square error of prediction were 0.0179 and 0.0143 by partial least square regression. The optimized calibration model was used to predict the content of epoxy value and CC double bond value in the photothermal curing process, it proved that the silicone resin cured under UV-radiation and heat. This novel method provided a promising approach to analysis the curing mechanism and quality parameters of resin.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 32
·e52765
·
IF 3.057
Pengjia Shan,Hengyu Lu,Ning Chen,Hongzhi Liu,Xianhui Zhang,Xiaohuan Liu
Designing biobased hyperbranched polyesters from vegetable oil has been attracting considerable interests from academic industrial communities. Herein, a novel fully biobased hyperbranched polyester (HBPE) was prepared by self-condensation of AB 2 -type bioderived monomer based on methyl ricinoleate (MR), a castor oil-derived renewable chemical. The reaction conditions were optimized to obtain the AB 2 -type monomer in a high conversion ratio (up to 87%). The self-condensation of AB 2 -type monomers was carried out in the presence of two kinds of transesterification catalysts (Ti(OBu) 4 versus Zn(Ac) 2 ), among which Ti(OBu) 4 was found to be more efficient one and yield higher molecular weights in the range of 5800~11,500 g/mol. The resulting HBPEs were characterized in terms of Fourier transform infrared spectroscopy, nuclear magnetic resonance, differential scanning calorimetry, and thermogravimetric analysis. The degree of branching was calculated to be 0.33~0.39. Thermal analysis revealed that the as-prepared HBPEs were amorphous with tunable glass transition temperatures ranging from −44.8 to −24.6°C. All the prepared HBPEs exhibited good thermal stability with the maximum onset decomposition temperature ( T onset ) up to 294.6°C. These structural features and properties of resulting biobased HBPEs enabled them to act as a potential ‘greener’ additive for polymers.
研究领域:
材料科学
·
生物基材料
·
有机化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）