JOURNAL OF APPLIED POLYMER SCIENCE
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2022
·Vol. 139
·期 42
·e53041
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IF 3.057
Yijun Zhang,Dawei Pan,Changfan Chang,Hua Liu,Zuozhen Liu
A highly reactive intrinsic epoxy flame retardant FREP was successfully synthesized via ring-opening reaction between DOPO and amino-tetrafunctional epoxy resin (AG-601), and the structure of the synthesized FREP was characterized by FTIR and MS. FREP was then introduced into the epoxy resin as an additive, aiming to improve fire safety. The flame-retardant properties and thermal stabilities of epoxy thermosets were investigated by limiting oxygen index (LOI), vertical burning test (UL94) and cone calorimetry (CONE). The results indicated that EP/FREP-4 thermoset passed UL94 V-0 rating with a LOI value of 34.6%, where the phosphorus content was 1.5 wt%. When compared with neat EP, the peak heat release rate (pk-HRR), total heat release (THR) and total smoke production (TSP) decreased by 63.1%, 42.6%, and 22.1%, respectively. Meanwhile, the lower av-EHC of EP/FREP thermosets indicated that FREP plays a significant role in gas-phase flame retardancy. Additionally, DMA analysis showed that FREP improved the crosslinking density of EP, which had little effect on the glass transition temperature ( T g ). Thermogravimetric analysis (TGA), Py-GC/MS analysis, and SEM were used to investigate the flame retardant mechanism. Excellent flame retardancy was attributed to phosphorus and nitrogen's synergistic effect in the gas and condensed phases.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 41
·e52996
·
IF 3.057
Yue Qin,Mengdi Chen,Jinzhao Li,Yuechuan Wang
Cycloaliphatic diepoxides, CAEs, are well known for their better thermal, chemical and optical properties, compared with the glycidyl ether type epoxides. However, the shortages including low moisture resistance, and high reflective index or high dielectric constant limit their use for the emerging advanced optical and electronic applications, In this work, we have synthesized two new cycloaliphatic diepoxides containing different fluorinated linkers (2,2′-((2,2,3,3-tetrafluorobutane-1,4-diyl)bis(oxy))bis(7-oxabicyclo[4.1.0]heptane) (TCE) and 2,2′-((2,2,3,3,4,4,5,5-octafluorohexane-1,6-diyl)bis(oxy))bis(7-oxabicyclo[4.1.0]heptane) (OCE) and characterized their chemical structures using 1 H NMR, 19 F NMR, and Fourier transform infrared spectroscopy. We have cured these two fluorine-containing CAEs, using hexahydro-4-methylphthalic anhydride (HMPA) and compared them with a commercial CAE, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate (ERL-4221) under the same condition. Compared to the cured ERL-4221 (C-ERL-4221), the cured fluorinated CAEs (C-OCE, C-TCE) have much better water resistances (saturated water absorption after 6 days in water: 0.70%, 1.72%, and 2.83%, for C-OCE, C-TCE, and C-ERL-4221, respectively) and lower dielectric constant ( D k ) ( D k : 2.54–2.44 and 2.78–2.66 vs. 4.01–4.00 @ 1 Hz-5 MHz), and similar thermal stability (the statistical heat-resistant index [ T s ]: 169°C, 175°C vs. 175.5°C), although their glass transition temperature ( T g ) and storage moduli are lower ( T g : 136°C, 171°C vs. 250°C; moduli: 0.56GPa, 1.25GPa vs. 1.38GPa). These results reveal that fluorine atoms on the linkers effectively reduce dielectric constant and improve hydrophobicity and wettability, providing new insights into the design of fluorine-containing cycloaliphatic diepoxides.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 38
·e52896
·
IF 3.057
Jiaojiao Lv,Bing Chen,Botuo Zheng,Mingfeng Chen,Huawei Qiao,Shanshan Li,Huagui Zhang
Aimed at promoting the flame retardancy of epoxy resin (EP) and widening its applications, a novel flame retardant, poly(phosphorus-silicon-alkyne) (PPSA), is synthesized from poly(silicon-alkyne) and 9,10-dihydro-9-oxa-10-phenanthroline-10-oxide (DOPO) to modify EP. The structure of PPSA is characterized by Fourier transform infrared and 1 H nuclear magnetic resonance. The PPSA introduction into EP significantly improves its chemical and physical properties. When containing 2.5–10 phr of PPSA, the modified EP achieve better flame resistance capability than neat EP. In particular, EP/PPSA-5.0 reaches a limiting oxygen index value of 31.2% and passes vertical burning test (UL-94) V-0 rating at the same time. The total heat release and total smoke production are lowered by 31.1% and 24.9%, respectively. In addition, the initial decomposition temperature ( T 5% ) of the modified EP is basically unchanged thanks to good stability of PPSA. Characterization of char residues generated in the combustion of EP/PPSA reveals that PPSA protects the EP from fire by diluting flammable gas with phosphorus free radicals and forming compact thermal stable layer containing silicon and phosphorus. Subsequently, measurements of mechanical properties show that impact strength and flexural strength are markedly improved by PPSA incorporation. Therefore, PPSA modifies EP to obtain excellent thermal stability and mechanical properties, justifying an outstanding flame retardant with comprehensive properties.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 35
·e52842
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IF 3.057
Jie-Ping Fan,Cong-Bo Huang,Yu-Tong Cheng,Chun-Fang Xie,Hui-Ping Chen,Hai-Long Peng
Bio-macromolecule hemoglobin (Hb) is a kind of iron-rich metalloprotein that abundant in erythrocytes with various physiological properties. Separating Hb from bio-matrix with high efficacy is crucial to Hb application but quite challenging. In this study, a supermacroporous molecularly imprinted membrane (MIM) was prepared with high performance on recognizing bovine hemoglobin (BHb). By using the silk fibroin and calcium alginate as mechanical modifiers, the mechanical strength of the prepared membrane was significantly improved to at around 0.25 MPa, and the supermacroporous structure in MIM was also formed. The MIM adsorption capacity of BHb was as high as 121.8 mg g −1 at the initial concentration of 0.5 mg mL −1 . The MIM separation factor of BHb from BHb/BSA mixtures was as high as 7.34, and the relative imprinting factor was at around 4.0. The prepared MIM demonstrated the superiority and the valuable application prospect on specific separation of BHb.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 38
·e52920
·
IF 3.057
Wei Wang,Li Lei,Qiuru Bao,Yuan Liu,Qi Wang
The flame retardant work of polyolefin materials has always been a challenge in the industry. Herein, we report a triazine charring agent (TM) containing hydroxyl and triazine ring. Combined with ammonium polyphosphate (APP), TM was applied to prepare flame retardant thermoplastic polyolefin (TPO) composites. The results of thermogravimetric analysis (TGA) test show that TM has high initial pyrolysis temperature and retention rate of char residue at high temperature. The UL-94, limit oxygen index (LOI) and cone calorimetry tests (CCT) were used to characterize the flame retardancy of TPO composites. The UL-94 V-0 rating and LOI value of 29.2% are achieved with a loading of 9.17 wt% flame retardant (TPO-3). In particular, the fire performance index (FPI) associated with the flashover time also increases to 0.037 m 2 s/kW compared with TPO (0.030 m 2 s/kW). The synergistic effects of APP/TM were investigated in depth. The results show that APP/TM system forms a dense and continuous char layer on the surface of TPO during combustion, which effectively insulates the substrate from heat and oxygen erosion. Additionally, APP/TM system also plays a weak but important flame retardant role in the gas phase, including quenching effect of phosphorous compounds and dilution effect of non-combustible gases.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2022
·Vol. 139
·期 38
·e52917
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IF 3.057
Chengyu Shi,Yulei Zhang,Xinyuan Lu,Zaozhen He,Aizhao Pan,Gang Chang,Ling He
The demand for highly-durable protective coatings for use in extreme environments is continually growing, however, poor durability and adhesion restricted their practical applications. Herein, we prepared a novel solution-processable graphene-based copolymer for fabricating highly-durable protective coatings. The random-structured copolymer GO- g -(PMMA- co -PMPS) was prepared by graphene-based initiator (GO- g -Cl) initiating methyl methacrylate (MMA) and 3-methacryloxypropyltrimethoxysilane (MPS) via surface-initiated atom transfer radical polymerization (SI-ATRP). The copolymers rendered the coatings with high transmittance (~95%), high hydrophobicity (water contact angles = 113.8 ± 2.13°), and strong adhesion (1.26–1.38 MPa). Tetrahydrofuran (THF)-casted coating surface presented a higher Si content and greater surface roughness than that cast from dimethyl carbonate (DMC), yielding more hydrophobic coating than those cast from DMC. The coatings could be coated on different substrates (glass, aluminum, and sandstone); and besides, the structures and performance of the coatings remained unchanged, even exposing to acid/alkali, salt, and ultraviolet light irradiation. These high-performance properties make the GO-based copolymers ideal candidates for fabricating high-durability protective coatings.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 35
·e52822
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IF 3.057
Hejia Chang,Qinghu Meng,Defa Liu,Yue Wu,Zhizhou Yang,Bin Sun,Fang Liu,Yu Liu
Synthesis of hollow spherical polyaniline (HSPANI) with the merits of facile strategy, low cost, low safety risk and high adsorption capacity of Cr(VI) is always a big challenge. In this manuscript, we proposed a facile way to preparation of HSPANI by using the poly(styrene-co-acrylic acid) sphere as template. The results indicated that HSPANI was emeraldine comprised of lots of basically uniform hollow spheres, and its average pore diameter was about 300 nm. HSPANI displayed high adsorption capacity of Cr(VI), and its value arrived at 601.3, 347.8, 235 mg g −1 at pH = 1, 2, and 3, respectively, which were high than many other adsorbents. The endothermic, spontaneous and chemical adsorption process was responsible for this adsorption. The Cr(VI) adsorption capacity was significant relied on its pH, contact time, Cr(VI) concentration and adsorption temperature. The adsorption behavior was well agreed with pseudo second-order equation and Redlich–Peterson isotherm models. HSPANI exhibited remarkable selectivity for adsorption of Cr(VI) even if the K + , Cu 2+ , NO 3 − and SO 4 2− were coexisted. HSPANI also displayed excellent regeneration performance. Therefore, this work not only provided a facile way to synthesis of hollow spherical polyaniline, but also supplied a potential adsorbent for adsorption of Cr(VI) from the industrial wastewater.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 35
·e52814
·
IF 3.057
Meiyuan Ma,Shuai Wang,Yue Liu,Hailong Yu,Shitao Yu,Congcong Ji,Haiyan Li,Genkuo Nie,Shiwei Liu
With concern to sustainable development, it is necessary to establish a recycling process of polyethylene terephthalate (PET). Methanolysis of PET is promising for chemical recovery of PET and the products are mainly dimethyl terephthalate (DMT) and ethylene glycol (EG), but the conditions of state-of-art depolymerization are severe. Here, we synthesized ionic liquid [HO 3 S-(CH 2 ) 3 -NEt 3 ]Cl-[ZnCl 2 ] 0.67 with Brönsted–Lewis di-acid and used it to efficiently catalyze the methanolysis of PET ( m methanol : m PET about 4) at milder temperature of 195°C with yield of DMT about 78.4%. Reaction kinetics was studied and the result indicated the depolymerization of PET was a first-order kinetic reaction with the apparent activation energy of DMT formation about 17.63 kJ mol −1 . Random sampling experiment was also conducted and the results showd that DMT was the product of deep depolymerization of PET and two methanol molecules were needed to form DMT and EG in the depolymerization process. This study provides an efficient method to the recycling use of PET and wais significant to waste recovery and green environment.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 42
·e53034
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IF 3.057
Yu Feng,Ziyuan He,Zhijie Yang,Wenxin Tang,Qingguo Chi,Qingguo Chen
The bottleneck problem of the development of high-voltage motors to a larger capacity can be solved if the thermal conductivity is improved without sacrificing the insulation characteristics of the main insulation material. In this paper, a spraying technology based on electrospinning is proposed that can evenly spray boron nitride (BN) with high thermal conductivity onto the surface of mica tape. With the increase in BN content, the insulation and thermal conductivity of mica tape are optimized to varying degrees. When the BN content reaches 2.25 wt%, the in-plane conductivity increases from 1.6 to 2.7 w/(m K), while the out-of-plane conductivity increases from 0.17 to 0.26 w/(m K). Additionally, the direct-current (DC) breakdown strength has increased from 90.6 to 96.9 kV/mm and the dielectric constant and dielectric loss are almost unchanged. Finally, through simulation verification, if the modified mica tape is applied to the main insulation of a synchronous motor, the operating temperature of the motor insulation will be reduced from 73.5 to 66.1°C. This study provides a new research idea for the preparation of high thermal conductivity insulating materials.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 41
·e53004
·
IF 3.057
Zheng Qu,Jiamin Huang,Guoliang Wu,Liangliang Dong,Chunfang Zhang,Yunxiang Bai
Urgent needs for the removal of volatile organic compounds (VOCs) from gas streams has stimulated a vigorous research for high-performance separation membranes. Herein, porous iron-organic molecular cage (Fe-cage) embedded polydimethylsiloxane (PDMS) mixed miatrix membranes (MMMs) were fabricated through emulsion casting method for efficient VOCs removal. The membrane separation performance was systematically investigated by separating VOC/N 2 gas mixtures under various operating conditions (e.g., feed concentration, operating temperature) using n -hexane, n -heptane, and cyclohexane as model organic vapors. It was found that the resultant membranes demonstrated homogeneous Fe-cage dispersion and intimate interfacial adhesion. With the increase of the Fe-cage loading, the MMMs demonstrated obviously improved permselectivity for the separation of n -hexane/N 2 and n -heptane/N 2 . The MMM containing 4 wt% Fe-cage showed a n -heptane permeability of 1657 × 10 −8 mol μm m −2 s −1 Pa −1 and a n -heptane/N 2 selectivity of 145 at 25°C when the feed concentration is 4.3 mol%. These values were 231% and 158% of those for the pristine PDMS membrane, respectively. Furthermore, the VOC permeability and VOC/N 2 selectivity of the membranes increased with decreasing operating temperature or increasing feed concentration. Because of its excellent mixed-gas VOC/N 2 permselectivity, the Fe-cage embedded PDMS membrane could find use in petrochemical applications such as gasoline vapor recovery.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 39
·e52928
·
IF 3.057
Ruonan Liu,He Liu,Tong Lyu,Kun Chen,Zhaoyang Wang,Ye Tian
Recent developments in hydrogel functional materials have created opportunities for building flexible sensors with multiple kinetic properties. Despite this, the research of multifunctional hydrogels for sensor applications is still a challenge. Herein, we present a recyclable multifunctional hydrogel synthesized from polyvinyl alcohol (PVA), hydroxyethyl cellulose (HEC), glycerin, and borax with three different states (named PHG, PHG-F, and PHG-S, respectively). Among them, PHG hydrogels have unique transparency, plasticity, self-healing, injectability, electrical conductivity and thermal sensitivity, and can be used to detect temperature changes with high accuracy and fast response. PHG-F hydrogels are obtained by cryogenic freezing of PHG hydrogels, which have strong mechanical properties and toughness (up to 0.66 MPa) and can provide excellent performance for human motion monitoring applications. PHG-S hydrogels, obtained by swelling of dried PHG hydrogels, have stronger mechanical properties and toughness (up to 1.31 MPa), and high conductivity (up to 2.3 S m −1 ) obtained by immersion in ionic salt solutions, making them very suitable for strain sensing. The tri-state and recyclable multifunctional hydrogels we developed might even prove useful for practical/smart materials, wearable devices, soft machines, and biomedical uses.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 41
·e52980
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IF 3.057
Siyao Zhu,Tongtong Zheng,Fan Li,Li Wang,Qiuran Jiang,Yi Wei,Wanshuang Liu
In this study, a latent imidazole hardener (CPI) for epoxy resins was synthesized through the nucleophilic substitution reaction between 2-methyl imidazolium (2MI) and hexachlorocyclotriphosphazene (HCCP). The chemical structure of CPI was characterized by Fourier transform infrared, 1 H NMR, and 31 P NMR. Curing kinetic studies (Kissinger and Ozawa methods) manifest that epoxy systems cured by CPI show higher apparent activation energy and curing temperatures than those cured by 2MI. Compared with 2MI, CPI shows distinctly improved thermal latency toward epoxy groups at both room temperature and 80°C, owing to the steric hindrance and electron-withdrawing effects of the introduced cyclotriphosphazene group. The results of dynamic mechanical analysis (DMA) and three-point bending tests indicate that the epoxy resins cured by CPI exhibit higher glass transition temperatures and comparable flexural properties in comparison to the corresponding epoxy resins cured by 2MI. As expected, the epoxy resins cured by CPI also show improved flame retardancy ascribed to the introduction of phosphorus and nitrogen elements. Finally, the optimized CPI/epoxy system was used as the polymer matrix to fabricate carbon fiber reinforced composites (CFRCs), and the resulting CFRCs show superior mechanical performance compared with the CFRCs based on the 2MI/epoxy system.
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高影响因子
危险品化学品经营许可证（带存储）