JOURNAL OF APPLIED POLYMER SCIENCE
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2022
·Vol. 139
·期 28
·e52614
·
IF 3.057
Quan Long,Xia Li,Yawen Huang,Qiuxia Peng,Xian Li,Liangbo Zhu,Jiajun Ma,Xu Ye,Junxiao Yang
The route via the cross-linking of hyperbranched prepolymers has potential advantage to construct low dielectric constant (low- k ) resins owing to the enhanced molecular free volume in hyperbranched structure. However, it is still a challenge to prepare hyperbranched resins with good film-forming property and low- k . In this paper, two hyperbranched polycarbosilanes with reactive benzocyclobutene groups were synthesized via hydrosilylation reaction to avoid the generation of Si O bonds for enabling the low polarity of chemical bonds. The spacing groups including phenyl or ethylene were incorporated into the hyperbranched structures, and the effect of the spacing groups on the physicochemical properties of hyperbranched polycarbosilane derived resins were investigated. The phenyl groups were found to effectively decrease the dielectric constant ( k ), while endowing the resins with good film forming ability and thermostability. The UV/thermally cured phenyl group resin owing to dual crosslinked structure, the patterns would not be deformed significantly during thermally cured process. Both hyperbranched polycarbosilane derived resins could be potential photoresists.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 28
·e52617
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IF 3.057
Yifan Suo,Wei Gao,Zhongwei Chen,Yuan Yu,Tingting Chen,Changxin Li,Qingwu Zhang,Juncheng Jiang
In this work, surface modification of cellulose nanocrystal (CNC) with diphenyl phosphate and Zn(OAc) 2 ·2H 2 O was prepared by a green method to obtain CNC-based flame retardant CNC@DPP@Zn and then added into epoxy resins (EP). The structure, morphology, and thermal stability of CNC@DPP@Zn were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), and thermogravimetric analysis (TG). Flame retardancy and combustion behavior of EP/CNC@DPP@Zn composites were characterized by TG, limiting oxygen index (LOI) test, vertical burning (UL-94) test and cone calorimeter tests (CCT). The results of CCT demonstrated that the peak heat release rate (pHRR), total heat release (THR), and total smoke production (TSP) of EP/8CNC@DPP@Zn composites reduced by 38.3%, 15.5%, and 36.0%, respectively, compared with pure EP. The char residues after CCT were characterized by laser Raman spectroscopy (LRS) and scanning electron microscope (SEM). Finally, the flame retardancy mechanism of CNC@DPP@Zn was proposed.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 43
·e53042
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IF 3.057
Jin Liu,Tianhao Wang,Canmin Hu,Li Lei,Yu Liang,Zideng Gao,Xueqin Ren,Shuwen Hu
Degradable plastic materials made from biopolymer Chitosan (CS) present one of the alternatives to plastic bags for food packaging, but the stability and durability limits its application. Herein, we demonstrated a facile method of producing hydrophobic CS/salicylic acid (SA) film in organic phase for the first time. SA, which can destruct hydrogen bonds of CS was initially blended with CS in N, N-dimethylacetamide using a catalyst. On this basis, CS/SA blend was crosslinked via isocyanate to the hydrophobic CS-SA film. The derivatives structures were characterized using SEM, FTIR, UV-Vis, and fluorescence spectrum. The film-forming ability of CS was maintained, while the hydrophobicity, mechanical strength, and thermal stability of films were improved. These dramatic improvements occurred with the blending effects of CS and SA and the crosslinking effects of organic isocyanate cross linker. The permeabilities to water vapor and water-soluble substances of film were promoted, which are conducive to the application of the film as food packaging. The demonstration of bacteriostatic and grape preservation properties featured the super performance of the synthetic CS/SA film. Our work provides novel food preservation materials, which can replace the commonly used packaging materials and promote the development of the degradable food packaging plastic bags field.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 44
·e53082
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IF 3.057
Yuanhao Zhang,Yubo Zhou,Zhen Wang,Jingling Yan
Colorless polyimide (CPI) films showed great potential for flexible display applications due to their unique combination of excellent optical transparency, and outstanding thermal and mechanical properties. Herein, a series of colorless poly(amide-imide)s were prepared via a conventional two-step method, using 1,2,3,4-cyclobutanetetracarboxylic dianhydride (CBDA), 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA), 2,2′-bis(trifluoromethyl)benzidine (TFMB), and 4,4′-diaminobenzanilide (DABA) as the monomers. The thermal, mechanical, and optical properties of these copolymers were optimized by adjusting the molar ratios of these monomers. The amide linkages significantly improved the mechanical properties and dimensional stability of the resultant CPI films due to strong hydrogen bonding interactions. In particular, CPI-f films with monomer compositions of TFMB (50 mol%), DABA (50 mol%), 6FDA (50 mol%), and CBDA (50 mol%) exhibited tensile strength of 177 MPa, modulus of 5.5 GPa, coefficient of thermal expansion value of 18 ppm K −1 , and glass transition temperature of 394°C. Furthermore, the optical properties of these copolymers were well balanced due to the adoption of CBDA, which can suppress the formation of charge transfer complexes. Specifically, these CPI films displayed transmittance at 550 nm of >88%, b * values of <5.5, haze values of <1%. The aforementioned results revealed that copolymerization is an effective strategy to achieve CPIs with excellent comprehensive properties.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 43
·e53061
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IF 3.057
Binglun Gao,Lianwei Sun,Xin Chen,Xiaobo Zhai,Junchi Zheng,Xin Ye,Jianmin Lu,Anchao Feng,Liqun Zhang
The focus of this paper is to report the quantitative synthesis of bis-epoxy end functionalized polyisoprene (BETPI) macromonomers by anionic polymerization and reversible addition fragmentation chain transfer (RAFT) polymerization. For anionic polymerization, more stable and sterically hindered living anions polyisoprene (Li + -PIp-Li + ) react with epichlorohydrin (ECH) for the synthesis of well-defined BETPI. For the high-pressure RAFT polymerization, a novel bis-epoxy end functionalized trithiocarbonate (BODAAT) is designed as RAFT agent for the polymerization of isoprene monomer to obtain well-defined BETPI. The functionalities of the resulting BETPI are analyzed by Fourier transform infrared spectroscopy (FT-IR), NMR, and size exclusion chromatography (SEC). Through two polymerization methods, the BETPI with 600–1000 Da of molecular weight and over 75% of epoxy end capping rate is obtained, which can be further utilized as highly reactive liquid macromonomers.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 40
·e52956
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IF 3.057
Mengyu Chen,Licheng Liu,Gang Wang,Zhuoyu Liu,Yingfeng Yu
The biomass-based chemicals from renewable resources are countermeasures to ease the problem of fossil fuel shortage. This work is to develop a biobased functional reactive modifier for thermosetting epoxy resins appropriate for excellent overall performance. The novel maleimide-cardanol modifiers (CA-HPM) is synthesized from natural extract cardanol (CA) and N -(4-hydroxyphenyl) maleimide (HPM), which is then mixed with phenolic epoxy resin and linear phenolic novolac resin systems. CA-HPM plays a versatile role in tuning the comprehensive properties of epoxy such as thermal property, adhesive property, and thermo-mechanical property. Systems with CA-HPM show slightly lower curing activity and distinct decreased single glass transition temperature ( T g ). Besides, the crosslinking density of the cured resin increases, meanwhile the thermal stability keeps at high level, which is due to the rigid five-membered ring structure of maleimide. Metal lap shear test results manifest that the adhesion between epoxy resin and metal interface augments. With 10% CA-1HPM, the cured resin exhibits lower equilibrium water sorption (1.88%) and diffusion coefficient (2.94 × 10 −8 s −1 cm 2 ). This biobased functional reactive modifier has provided balanced overall performance and would pave the way to a wide range of possible “eco-friendly” applications.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2022
·Vol. 139
·期 39
·e52928
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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
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 32
·e52746
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IF 3.057
Chaoyu Wang,Zhi Hao,Zhu Luo,Le Yang,Qin Zhou,Jiaxing Guo
Efficient heat dissipation is very crucial for the performance, service life, and reliability of modern electronic devices. It is very challenging to improve heat dissipation efficiency through innovative material structure design. Therefore, in the work, dopamine (PDA) is used to coat the surface of graphite (C) with its excellent surface coating modification ability, so that the C surface has oxygen-containing groups to change its electronegativity, and Fe 2+ and Fe 3+ in the solution are attracted to the surface of C, and then in situ redox reaction occurs on the surface of C to generate magnetic graphite (Fe 3 O 4 @C). Fe 3 O 4 @C is uniformly dispersed into liquid silicone rubber (LSR) by solution blending, and Fe 3 O 4 @C performs integral directional filling in the LSR under the action of magnetic field ( B = 140 mT), thus preparing Fe 3 O 4 @C/LSR composites. Through magnetic field orientation, the thermal conductivity of Fe 3 O 4 @C/LSR composites reach 1.25 W/m·K when the content of Fe 3 O 4 @C is 100 phr, which is 410% higher than that of pure LSR (0.2447 W/m·K). Infrared thermal imaging test shows that Fe 3 O 4 @C/LSR composites has good heat dissipation performance, Fe 3 O 4 @C/LSR composites have shown great potential in terms of flexibility and high thermal conductivity.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2022
·Vol. 139
·期 31
·e52731
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IF 3.057
Qi-Meige Hasi,Yuping Guo,Shanshan Wang,Jiale Yu,Zhichao Han,Chaohu Xiao,Yuhan Zhang,Lihua Chen
Efficient elimination of organics or oils in water has become a global concern due to their severely environmental pollution. In this work, two kinds of absorbents based on the doping of conjugated microporous polymers onto sponges (CMPs@sponges) were prepared by in situ Sonogashira-Hagihara coupling reaction of the monomers in the presence of melamine sponge. The as-synthesized CMPs@sponges possess excellent thermal and physicochemical stability. Owing to the excellent hydrophobic character of the CMPs@sponges, which exhibit high oil/water separation efficiency through adsorption process. The CMPs@sponges show desirable ability for the adsorption of oils and organic solvents with the values of 24–64 g/g and 13–36 g/g, and the adsorption properties remain unchanged after 10 cycles with excellent cycling stability. Even the CMPs@sponges are immersed in different pH solutions, which still maintain their original superhydrophobicity. In addition, CMPs@sponges can constantly separate and recover oil and organic solvent based on the help of vacuum pump, and the separation efficiency still remained above 95% after 10 repetitions. It was worth noting that the CMPs@sponges can remove not only the organic solvents but also the trace benzene contaminants from water, and with the removal rate of more than 85%. Furthermore, the as-synthesized CMPs@sponges possess high oil/water separation properties that may be attributed to the physical adsorption, and the π-π interactions and hydrophobic interactions. Therefore, due to the designable flexibility of CMPs, which make the CMPs-based novel materials are excepted to an excellent candidate for applications of oil/water separation and water purification.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 31
·e52724
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IF 3.057
Chunhui Du,Jintai Hu,Fen Chen
Polypropylene (PP) porous flat membrane is ultrathin and has high porosity, which is suitable for the support of forward osmosis (FO) membrane. However, its high hydrophobicity is its Achilles heel. In this study, dopamine and UiO-66-NH 2 were co-deposited onto the surface of PP support, and then interfacial polymerization was performed to fabricate a thin-film nanocomposite (TFN) FO membrane. The reaction-generated polydopamine improved the hydrophilicity of PP membrane, and at the same time enhanced the adhering of UiO-66-NH 2 to the support. The experimental results indicated that the UiO-66-NH 2 nanoparticles were anchored evenly on the surface of the support, which improved the water flux of FO membrane from 11.1 LMH (TFC, TFN-0 without UiO-66-NH 2 ) to 20.7 LMH (TFN-0.1, with 0.1 wt% UiO-66-NH 2 ) using 1 mol/L NaCl as the draw solution in FO mode. Compared with TFC membrane, TFN-0.1 membrane also exhibited relative lower specific salt flux (~0.252) and structural parameter (~379 μm). When separating sodium alginate foulant, the normalized water flux recovery ratio of TFN-0.1 was remained 0.89, and most of the fouling was reversible, as for TFC membrane the data decreased to 0.76 after 2 cycles of operation. These results suggested that UiO-66-NH 2 modified FO membrane exhibited good permeation and antifouling property.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 44
·e53071
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IF 3.057
Zihao Cheng,Wenzong Xu,Ding Ding,Chengwen Xu,Yunlong Xie,Mengxia Qiao
In this study, a nanofiller (M-DOPO-BN) was synthesized by surface modification of hexagonal boron nitride with vinyltrimethoxysilane (KH-171) and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), and compounded with aluminum diethyl phosphinate (ADP) to study their effects on flame retardant, smoke suppression and thermal conductivity properties of styrene-butadiene rubber (SBR). The results showed that the composites with an ADP content of 20 parts per hundred of rubber (phr) have good flame retardant properties, but the total smoke production increased significantly. The flame retardant properties of SBR composites compounded with 3 phr M-DOPO-BN and 17 phr ADP were not only further improved, but also the peak carbon monoxide production rate (pCOP) and peak carbon dioxide production rate (pCO 2 P) were reduced by 37.0% and 67.5%, respectively, compared with pure samples, showing a good smoke inhibition effect. In addition, the thermal conductivity of the composites have also been improved to a certain extent. The variable temperature infrared and residual char analysis of SBR composites showed that the reasons for its flame retardancy and smoke suppression are that M-DOPO-BN can catalyze the formation of carbon, and the silica and boron nitride generated by decomposition during combustion can improve the density of residual char.
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高影响因子
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