JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 139
·期 10
·51763
·
IF 3.125
Jiaxian Qiu,Yingrui Bai,Jinsheng Sun,Liyao Dai,Shaofei Lei,Fan Liu
Aiming at the lack of plugging agent for oil-based drilling fluid leakage in fractured formation, an oil-based gel-plugging agent with high structural strength and strong thermal stability was synthesized based on monomer polymerization and crosslinking. According to the preparation experiment, when the total concentration of methyl methacrylate (MMA) and butyl acrylate (BA) is 30% and the ratio is 6:4, the oil-based gel solution can be completely gelatinized from 80 to 200°C, which has high gel strength and controllable gelation time. The effects of total concentration of BA and MMA, the ratio of BA and MMA, synthesis temperature, oil-based drilling fluid invasion, shear effect, and fiber concentration on gelling performance were systematically studied. Fourier transform infrared molecular structure analysis showed that the oil-based gel contained benzene ring group and ester characteristic group. From the rheological properties of oil-based gel with 30% gelling agent at 160°C, it could be seen that the elastic modulus G ′ of 10 Hz is 232 kPa, which is much larger than the storage modulus G ″ is 99 kPa, which reflects the solid properties and has good elasticity and high strength. The displacement experiment of sand filling pipe and dynamic and static plugging experiment of high temperature and high pressure shows that the oil-based gel has high bearing capacity in fractures and sand filling pipe. The bearing pressure is 3.01 MPa in 6 mm fractures, and the bearing pressure gradient is 0.602 MPa/cm.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 139
·期 4
·51551
·
IF 3.125
You Wu,Yujuan Jin,Jian Huang,Huafeng Tian,Yunxuan Weng
Phenyl terminated hyperbranched polyesters (HBP-Bs) were synthesized based on Boltorn-type hydroxyl terminated HBPEs and characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance, gel permeation chromatography, and so forth. The prepared HBP-Bs were used to toughen poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) directly by melt blending. The thermal properties, rheological properties, mechanical properties, and microstructure of the PHBV/HBP-Bs blends were studied in detail. Comparing with pure PHBV, the crystallinity of the PHBV/0.5 phr HBP-Bs blends decreased by 14.10% (from 64.39% to 55.04%), the impact strength increased by 158.30% (from 7.41 kJ·m −2 to 19.14 kJ·m −2 ), and the elongation at break increased by 400.00% (from 0.91% to 4.55%). It can be seen from the scanning electron microscope that the fracture surface of the PHBV/HBP-Bs blends became rough with the increase of HBP-Bs, even with large filamentous structures and tiny holes, which further demonstrated that HBP-Bs acted as an excellent toughening effect on PHBV.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 139
·期 7
·51627
·
IF 3.125
Tingting Wang,Jinqing Wang,Zhangpeng Li,Mingqiang Yue,Xiaoli Qing,Pengxia Zhang,Xiaozhu Liao,Zengjie Fan,Shengrong Yang
Conductive hydrogels with high flexibility, superior formability, good mechanical elasticity, and excellent biocompatibility have emerged as promising materials for broad applications in flexible/wearable electronic devices. In this work, a conductive dual-network PVA/SA/MXene hydrogel (PSM-h) composed of polyvinyl alcohol, sodium alginate, and MXene (Ti 3 C 2 T x ) is constructed by a green method without using chemical crosslinking agents. The resultant hydrogel with dual-network feature shows excellent cytocompatibility (no toxicity for human umbilical cord mesenchymal stem cells), high stretchability (up to 263%), and superior anti-fatigue ability (stretched up to 1000 cycles). More importantly, PSM-h based strain sensor presents good sensing sensitivity with a fast response time (62.5 ms) and a low detection limit even under a very slight strain of 0.2%. In terms of the practical application, the PSM-h based strain sensor can be applied to detect and distinguish various human motions.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 139
·期 9
·51731
·
IF 3.125
Mengdi Chen,Jianna Bao,Mingfu Zheng,Xianming Zhang,Wenxing Chen
Melt post-polycondensation (MPP) process is one of manufactures industrially that can efficiently increase the molecular weight of polycarbonate (PC). Herein, the MPP experiments of several PC materials using quaternary ammonium hydroxides and alkali metal compounds as the catalyst in the film state are studied. The reaction products are characterized by Ubbelohde viscometer, DSC, 1 H-NMR, ultraviolet spectrophotometry, advanced polymer chromatography and rotational rheometer. It is found that MPP can effectively improve the intrinsic viscosity of PC. After a certain reaction time at a specific temperature, the number average molecular weight ( M n ) of PC is raised from 19,000 to 54,600 g/mol. Furthermore, the 1 H-NMR results reveal that Fries rearrangement products are produced during the MPP process. Based on the functional group model, a reaction kinetic model, combining the effects of the main melt polycondensation reaction and the Fries rearrangement reaction, is established for the first time. The reaction rate constants at different temperatures and the reaction activation energies of the two PC materials are obtained. This work provides a new reaction kinetics model to guide the MPP process of PC, which contains Fries rearrangement reaction.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 139
·期 10
·51742
·
IF 3.125
Danning Gao,Qi Zhang,Zhifeng Liu,Fureng Zhang,Faliang Gou,Guiying Xing,Shujing Zhou,Linjun Shao,Jinjing Li,Yijun Du,Chenze Qi
We report the synthesis of palladium nanoparticles encapsulated N-doped carbon nanofibers derived from environmentally benign chitosan. Palladium salt was incorporated into the chitosan/sodium polyacrylate composite nanofibers by electrospinning, followed by carbonization under argon atmosphere to prepare palladium encapsulated mesoporous carbon nanofibers (Pd@Carbon). SEM images shows that the fibrous structures were well retained after carbonization processes. The Raman spectra demonstrates that the ratio of graphite carbon were increased with the carbonization temperature. X-ray powder diffraction and transmission electron microscopy analysis shows that PdO and Pd nanoparticles were formed in the carbon fibers and their sizes grew with the carbonization temperature. The sizes and concentrations of submicroscopic pores inside the nanofibers were analyzed by nitrogen adsorption/desorption experiments and positron annihilation lifetime spectra. Heck reaction catalysis result shows that high carbonization temperature could improve the catalytic activity of Pd@Carbon nanofibers and the nanofibers carbonized at 800°C had the highest catalytic activity. Moreover, the catalytic activity of these novel composite nanofibers was well retained even after recycling for 13 times. The excellent catalytic performance of this fibrous palladium catalyst can be attributed to the N-rich carbon nanofibers and encapsulation of palladium active species inside the ultrathin mesoporous carbon fibers.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 139
·期 9
·51724
·
IF 3.125
Xiaoqing Qiu,Daqian Wang,Qing Li,Xiaoyue Li,Xiaowei Zhao,Zhiwei Li,Xiaohong Li,Zhijun Zhang
Melamine-formaldehyde (MF) foam has wide applications due to good flame retardancy, excellent sound absorption, and high thermal stability. However, the recycling of MF foam wastes remains a challenge due to its thermosetting nature. Here, we demonstrate a new strategy for discarded foams as solid adsorbents for removing tin ions in simulated tin-containing wastewater. Results showed that the removal rate of tin in simulated wastewater is as high as 99.996%. Moreover, after simple calcination, as-obtained products can be used as high-efficiency flame retardants for flexible poly(vinyl chloride) (PVC), reducing the peak of heat release rate and total smoke production of PVC by 51.8% and 45.8%, respectively, under the condition of 2.5 wt.% addition. In short, this strategy successfully converted MF foam and tin wastewater to valuable flame retardants, opening the way for the environmentally friendly recycling of MF waste and the simultaneous treatment of tin-containing wastewater.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 139
·期 19
·52104
·
IF 3.125
Dongsheng Li,Zhiyong Zhang,Siqi Wang,Miaojun Xu,Bin Li
In this article, a monomolecular intumescent flame retardant 1,4-bis (diethyl methylenephosphonate) piperazine defined as BDEMPP was introduced into epoxy resins (EP) thermosets. The fire safety, combustion behavior, thermal properties, mechanical performance, transparency, and flame-retardant mechanism of EP/BDEMPP thermoset were investigated systematically. The EP thermosets passed UL-94 V-1 level with the limit oxygen index value of 28.3%, and the release of heat and smoke were inhibited when 9 wt% BDEMPP was added. Moreover, the tensile strength and modulus, flexural strength and modulus, charpy impact strength of EP/9 wt% BDEMPP were increased by 15.0%, 22.4%, 15.4%, 15.6%, and 22.6% in comparison of pure EP thermosets, respectively. EP/BDEMPP composites possessed good transparency and the transmittance of EP/9 wt% BDEMPP was 87.1% at 600 nm UV irradiation. The investigation of flame retardant mechanisms demonstrated BDEMPP exerted flame retardant effect both in gaseous and condensed phase. BDEMPP exhibited good compatibility, flame retardancy, smoke suppression, and mechanical enhancement for EP thermosets.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 139
·期 18
·52064
·
IF 3.125
Xinjun Wang,Lijun Qian,Juan Li
Amino acid-triazine copolymer (CC-Lys) was prepared by using lysine (Lys) and cyanuric chloride (CC). The structure and performance of CC-Lys were tested by using Fourier transform infrared spectroscopy and thermogravimetric analysis. The CC-Lys, ammonium polyphosphate (APP) and organic montmorillonite (OMMT), were applied in ethylene-vinyl acetate (EVA) to improve its flame retardancy. The results showed that 20 wt% APP/CC-Lys/OMMT makes EVA achieve the UL-94 V0 rating. The reactions among APP/CC-Lys/OMMT release some incombustible gases and promote the formation of a porous char layer with good barrier performance during combustion. Moreover, the quality of the char layer is improved. In addition, the peak of heat release rate of EVA composite is reduced by 87% and time to ignition is delayed. This work provides a good flame retardant system for EVA.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 139
·期 17
·52012
·
IF 3.125
Yongxian Shen,Hongjun Zhou,Qingbing Guo,Hongchao Hu
In this study, the persimmon tannin powder modified polyurethane foam (PTP-PUF) was synthesized. The morphology of the foam was observed by SEM, the thermodynamic stability and mechanical properties of PTP-PUF were discussed for application. The effect of persimmon tannin powder content and initial pH on Cu(II) and Pb(II) biosorption on PTP-PUF was investigated. The adsorption equilibrium data for Cu(II) and Pb(II) fitted the Freundlich model and Langmuir model well, respectively. And the maximum adsorption capacity of PTP-PUFs for Cu(II) and Pb(II) ions were 96.06 and 112.2 mg/g at pH 5 and 323 K. The kinetic data was tested using pseudo-first-order and pseudo-second-order models. The results suggested that the pseudo-second-order model was the best one to describe the adsorption behavior of Cu(II) ( R 2 > 0.997) and Pb(II) ( R 2 > 0.985) onto PTP-PUF.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 139
·期 17
·52041
·
IF 3.125
Zhiyuan Song,Jie Wang,Qian Tao,Yang Yu,Hui Zhang,Chuanqun Hu,Hongyu Cen,Xuan Zheng,Tao Hu,Chonggang Wu
Zn-salt poly(styrene– ran –cinnamic acid) (SCA–Zn) ionomers were successfully synthesized via the melt neutralization of poly(styrene– ran –cinnamic acid) (SCA), which has a comparable molecular weight ( = 217,000) to commercial polystyrene (PS), with different mass fractions of ZnO (0.62, 1.6, and 3.9 wt.%) and the successful synthesis was confirmed by Fourier transform infrared spectroscopy. The mechanical properties, heat resistance, and processibility of the PS, SCA, and SCA–Zn samples were characterized. Compared to SCA, the three SCA–Zn ionomers exhibited significantly higher α cN values, with the ionomers containing 1.6 and 3.9 wt.% ZnO were 11.4% and 68.6% higher than that of SCA, respectively. Compared to commercial PS, SCA–Zn also exhibited significant improvements in heat resistance (glass transition temperature and vicat softening temperature both improved by about 20 °C) and impact toughness ( α cN values of the ionomers containing 1.6 and 3.9 wt.% ZnO were 69.6% and 156.5% higher than that of PS), while the processability of SCA–Zn was not significantly worse than that of PS. This method efficiently improves both the toughness and heat resistance of PS, providing an efficient way to expand the market application of styrenic resins.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 139
·期 17
·52016
·
IF 3.125
Xiaolong Lu,Jianshu Wang,Shuwei Cai,Ben Niu,Qin He,Xianru He
Recently, the research of blending anti-aging modification of nitrile butadiene rubber (NBR) has been widely reported, but the surface effect in the rubber aging process has been obviously ignored. Starting from the surface microstructure design, the construction of surface protection barrier may be a new anti-aging way. In this paper, the surface superhydrophobic NBR surf -polydopamine (PDA)-(SiO 2 -g-PFOMA) is prepared through a ordered modification of two-step physical deposition to NBR with PDA and SiO 2 grafted with Perfluorooctylmethacrylate (SiO 2 -g-PFOMA). By comparing the mechanical properties before and after aging, it is found that the DA surface pretreatment significantly improves the NBR thermo-oxidative aging. On this basis, surface superhydrophobic SiO 2 -g-PFOMA microstructure has set up to further prevents NBR from the attack of corrosive media such as acid, alkali, salt and water. After aging in HCl solution at 90°C for 96 h, the fracture strength, elongation and aging coefficient of NBR surf -PDA-(SiO 2 -g-PFOMA) compared with unmodified NBR(KB) were increased by 2.28 MPa, 48.76% and 0.18, respectively. This work can offer an surface anti-aging technology to NBR.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 139
·期 8
·51688
·
IF 3.125
Qibin Xu,Shengchang Zhang,Zexi Su,Dazhe Li,Shuheng Liang,Bo Li,Tingting Lian,Xiangpu Qin,Mengjin Jiang,Pengqing Liu
9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and DOPO derivatives had always been regarded as main candidates for improving the flame retardancy of epoxy resin (EP). In this paper, a novel reactive flame retardant DOPOMAH was synthesized from the reaction between DOPO and cis-butenedioic anhydride (MAH), thereafter acted as a co-curing agent for EP to remarkably improve the flame retardancy of matrix. The effects of DOPOMAH and DOPO on comprehensive performance of EP were systematically investigated and compared through dynamic mechanical analysis, mechanical performance testing, limiting oxygen index (LOI), vertical burning (UL-94), and cone calorimetry test. These results indicated that the excellent dispersion of DOPOMAH in EP makes the EP modified by DOPOMAH has good mechanical properties. When the content of phosphorus is 2.0 wt%, compared with the EP modified by DOPO (ED), the LOI of the EP modified by DOPOMAH (EDM) increased from 30.6% to 32.8%, and the UL-94 was also improved from no rating to V-0. Meanwhile, the peak heat release rate of EDM was only 51% of that of pure EP, which was slightly less than that of ED. Finally, a flame-retardant mechanism comparison between DOPOMAH and DOPO was discussed in detail to reveal the reasons why the flame reatardant effect of DOPOMAH was better than that of DOPO.
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高影响因子
危险品化学品经营许可证（带存储）