JOURNAL OF APPLIED POLYMER SCIENCE
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2020
·Vol. 138
·期 12
·50065
·
IF 2.52
Jingqi Luo,Chuanjie Fan,Xiaodong Zhou
A new type of polydopamine functionalized graphene oxide/carboxymethyl chitosan (DGO/CMC) composite aerogels was synthesized via sol–gel once-forming self-assembly and lyophilization. Polydopamine (PDA) on the surface of GO nanosheets replaced those traditional crosslinking agents to connect CMC chains via hydrogen bonding for the establishment of 3D porous aerogels. With the increasing proportion of CMC, the microstructure of aerogels changed from small pores to large plate-bridge-like pores. In addition, their maximum compressive strengths were 6.767, 11.94, and 16.98 MPa under 90% compressions, respectively, which increased in accordance with CMC content. Furthermore, the adsorption system of the aerogels was simulated well by the pseudo second-order kinetic model and the Langmuir isotherm model, with maximum mass adsorption capacities of 170.3, 186.8, and 312.8 mg/g for Cu 2+ , Ni 2+ , and Pb 2+ ions, respectively. These composite materials have potential applications for water purification because of their simple and efficient synthesis and excellent recyclability and reusability.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 6
·49801
·
IF 2.52
Fan Zhang,Jinhui Li,Tao Wang,Chao Huang,Fei Ji,Liang Shan,Guoping Zhang,Rong Sun,Ching-ping Wong
Low dielectric constant and low dissipation factor, superior hydrophobicity, excellent thermal and mechanical property, and good optical performance are desired for advanced electronic packaging of fan-out wafer level package (FO-WLP). An effective approach was introduced to fabricate novel fluorinated graphene/polyimide(FG/PI) nanocomposite films in this paper. FG nanosheets exhibit excellent dispersion in the PI matrix due to their high surface area with some oxygen-containing functional groups, and individual graphitized planar structure. Besides, the effects of the addition of FG on the dielectric, optical, mechanical, thermal properties as well as the hydrophobicity of the films are investigated with controlled amounts of FG. The dielectric constant and loss can be as low as 2.64 (at 10 6 Hz) and 0.00176 for PI-0.5wt% FG. And with the increase of the loading of FG, the thermal stability ( T 5 = 514°C) and mechanical property (tensile modulus = 2.11GPa, tensile strength = 93.23 MPa, elongation at break = 11.60%) has been improved successfully. Besides, the contact angles have been increased from 83° to 92° showing a superior hydrophobicity which is essential for the FO-WLP. Moreover, the incorporation of FG also proved excellent optical performance of 88% transmittance at 550 nm. Therefore, with the excellent comprehensive performance, the as-prepared FG/PI films possess widespread applications in the microelectronics especially in FO-WLP.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 2
·49666
·
IF 2.52
Benben Zhang,Zeyu Ye,Min Qin,Qingqing Wang,Yijun Du,Chenze Qi,Linjun Shao
A simple and green chemical modification coupled with electrospinning technique has been developed to incorporate tetrakis(triphenylphosphine)palladium [Pd(PPh 3 ) 4 ] inside crosslinked polystyrene nanofibers (Pd@CPS) as an efficient and stable heterogeneous palladium catalyst. The catalytic activities and recyclabilities of the prepared Pd@CPS catalyst have been evaluated by using Suzuki and Heck reactions of various aromatic halides separately with phenylboronic acid and alkenes. The Pd@CPS exhibited high-catalytic activities for the Suzuki and Heck reactions of aromatic iodides to afford the products in excellent yields (coupling yields >88%). The catalytic activities and the nanofiber structure remained essentially unchanged even after recycling for five times. The high activities and stabilities of the prepared Pd@CPS catalyst can be attributed to the ultrafine fiber and embedment of palladium active species inside the nanofibers.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 6
·49791
·
IF 2.52
Chenggong Li,Ying Li,Changdan Gong,Kunpeng Ruan,Xiao Zhong,Pan Pan,Chao Liu,Junwei Gu,Xuetao Shi
The thermal conductivity of bulk polymers is usually very low, which is due to the amorphous domains where chains are randomly entangled, improving the degree of the chain alignment and forming a continuous thermal conduction network are expected to enhance the thermal conductivity. A series of liquid crystalline monomer-poly (vinyl alcohol) dispersion (MDLC) films with high thermal conductivity containing microscopic-ordered structure were prepared by introducing a highly ordered liquid crystalline monomer (LCM) exhibiting Smectic phase. The thermal conductivity of MDLC films was strongly related to the amount of LCM, which firstly increased and then decreased with the increase of LCM content. The thermal conductivity of MDLC film reached up to 1.20 W m −1 K −1 when the content of LCM was 15 wt% and rapidly decreased to 0.85 W m −1 K −1 as the content of LCM further increased to 25 wt%. LCM with low content (1–15 wt%) showed good fluidity, dispersity and interfacial compatibility in PVA molecular chains, which further increases the regularity of molecular chains alignment.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 6
·49800
·
IF 2.52
Lu Wu,Longwei Li,Lujun Pan,Hai Wang,Yuezhen Bin
The preparation and application of hydrogel has been a hot research field in recent years. Here in, a composite hydrogel based on poly(vinyl alcohol) (PVA), carboxymethyl chitosan (CMCS), oxidized sodium alginate (OSA), and oxidized multiwall carbon nanotubes (OMWCNTs) was successfully prepared. Hydrogen and imine bonds of the hydrogel endowed the composite hydrogel with self-healing property and pH sensitivity. The fracture strength of the hydrogel was enhanced to about 0.8 MPa with the help of OMWCNTs, which was about 2.5 times compared with the one without OMWCNTs. Meanwhile, a new conductive network inside the hydrogel was constructed by OMWCNTs, which improved the conductivity of the hydrogel from 1.75 × 10 −4 to 7.02 × 10 −4 S/cm. The sensing test of the hydrogel showed that it could produce profound feedback signals for the deformation caused by external force and response to human body movements, such as finger bending, swallowing, and speaking.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 3
·49702
·
IF 2.52
Ping Wang,Zhaopei Cui,Xianhai Hu,Pei Xu,Yunsheng Ding
Biodegradable polylactide (PLA) and polyvinylidene fluoride (PVDF) blends containing the copolymer of PEGMA and 1-vinyl-3-ethylimidazolium bromide (PMI) were prepared, and the effects of ionic liquid segments of PMI on the compatibility of PLA and PVDF were investigated by dielectric relaxation spectroscopy (DRS). PMI can obviously improve the compatibility of PLA and PVDF, compared with the copolymer of PEGMA and vinyl imidazole (PMV). DRS showed that the compatibility of PLA and PVDF was related to the relaxation behavior of the blends, which was identified with Maxwell-Wagner-Sillars (MWS) interfacial polarization. The ε ' of PLA/PVDF/PMI blends was much higher than that of PLA/PVDF/PMV blends in the same temperature, resulting from the stimulation of MWS interfacial polarization by the ion mobility of PMI.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 2
·49667
·
IF 2.52
Mengting Li,Changgui Li,You Zhou,Hua Tian,Qiaoyuan Deng,Haifang Liu,Li Zhu,Xueqiong Yin
Microencapsulation is a widely-investigated technique used for the unstable material preservation since the wall materials prevent the core materials from loss and deterioration. To improve the stability of cinnamaldehyde (CAL), different microcapsule wall systems are fabricated by spray-drying, and then characterized by experimental methods to determine the most suitable wall materials. Surface morphology, encapsulation efficiency, effective loading capacity, as well as moisture absorption property are evaluated, and the results suggest that a three-matrix system of methyl cellulose (MC)/sodium alginate (SA)/MC or MC/carboxymethyl chitosan (CMC)/SA wall formulation is more suitable for CAL microencapsulation. Moreover, a novel quantitative method is also proposed to verify the most stable wall material microencapsulation. The quantitative results show that the highest activation energy (53.00 ± 2.24 kJ/mol) is observed for the MC/CMC/SA-encapsulated CAL microcapsule. Taken together, the results suggest that MC/CMC/SA wall formulation shows excellent barrier properties and is superior to other wall materials in preventing microencapsulated CAL deterioration. This study will be efficient in designing an ideal capsule for CAL microencapsulation.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 5
·49772
·
IF 2.52
Xiang Chen,Haojie Yu,Li Wang,Nan Wang,Qian Zhang,Weibin Zhou,Md Alim Uddin
There is a problem with directly loading insulin into the polymerized glucose-responsive microneedle (MN) patch due to that polymerization conditions and solvents may damage the activity of insulin. In this study, we report a totally polymerized phenylboronic acid-based MN patch, and insulin was directly loaded in MNs by a mild drop/dry procedure. MN patch was prepared by copolymerization of N -isopropyl acrylamide, N -vinyl-2-pyrrolidone, and 3-acrylamidoephenylboronic acid in MN mold. The MN patch showed good glucose-dependent swelling behavior in pH 9.0 at 27°C. After insulin loading procedure, insulin was distributed on and within the MNs. About 43.2% of total insulin was diffused into MNs' interior. As a result, the release of insulin on MNs' surface was uncontrolled by MNs and rapidly finished after ~10 min. However, the release of insulin within MNs was depended on glucose concentration, and insulin was released 1.6 times more at 4 g/L than at 1 g/L glucose concentration after 12 h. Although further improvements are needed to make MN patch responding in physiological environment, this work suggests a solution for directly loading insulin in polymerized glucose-responsive MNs.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 6
·49792
·
IF 2.52
Rui Yang,Boran Hao,Lin Sun,Kan Zhang
In this study, an amide functionalized bis-benzoxazine (AI-al) has been synthesized using allylamine, ortho -amide functional bis-phenol and paraformaldehyde as raw materials via Mannich condensation. This newly obtained benzoxazine has been used to react with polydimethylsiloxane (PDMS) through hydrosilylation to form poly(benzoxazine- co -amide- co -siloxane) (AI-al-PDMS) featuring siloxane, amide and benzoxazine as repeating units. The chemical structures of both oxazine ring-containing monomer and copolymer are confirmed by NMR and FT-IR spectroscopies. Besides, the thermally activated polymerization behaviors of AI-al and AI-al-PDMS are investigated by DSC, and the subsequent conversion of benzoxazole formation is studied by in situ FT-IR. Moreover, dynamic mechanical analysis and thermogravimetric analysis are used to determine the thermal properties of the cross-linked polymers. The resulting cross-linked poly(benzoxazole- co -siloxane) derived from AI-al-PDMS shows excellent thermal stability (no T g can be observed before 400°C; Td5 of 393°C) and low dielectric constants (2.52–2.13 in the frequency range of 1 Hz to 1 MHz), evidencing its great potential applications in electronic packing, aerospace, and other high-performance fields.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 5
·49762
·
IF 2.52
Yukai Su,Ting Sai,Shiya Ran,Zhengping Fang,Zhenghong Guo
For the purpose of promoting mechanical properties of bisphenol-A polycarbonate (PC) reinforced by rigid organic styrene–acrylonitrile copolymer (SAN) particles, styrene/acrylonitrile/glycidyl methacrylate terpolymer (SAG) was synthesized and applied as compatibilizer for PC/SAN blends. It is found that the phase morphology of PC/SAN/SAG blends is closely related with their mechanical properties. Large continuously distributed SAN phase or spherical dispersed SAN particles with average diameter over 2 μm tend to trigger premature tensile failure of blends due to stress concentration. The incorporation of SAG can simultaneously reinforce and toughen PC/SAN blends by controlling the size and distribution of the dispersed SAN particles. For the blends with fixed PC/SAN ratio, the elongation at break and fracture energy are markedly improved when SAN domain size is reduced by adding appropriate amount of SAG. Typically, for blends with a PC/SAN ratio of 75/25, adding 3 wt% SAG will cause the average diameter of SAN particles to reduce from 2.35 ± 1.20 to 0.74 ± 0.25 μm, meanwhile up to 95% increment in elongation at break and 115% increment in fracture energy is achieved.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 4
·49730
·
IF 2.52
Kunxiang Shi,Yucai Shen,Yunxu Yang,Tingwei Wang
A series of latent curing agents were developed by replacing the hydrogen atom on secondary amine in imidazole with methoxy polyethylene glycol maleate diesters via Michael addition reaction. Methoxy polyethylene glycol maleate diesters with different molecular weight also restrained the reactivity of tertiary amine in imidazole ring. The curing properties and pot-life of the modified imidazole/epoxy systems were measured by differential scanning calorimeter and rotational rheometer. The modified imidazole/epoxy system could be cured quickly at 175°C. The modified imidazole shows good latency. After stored for more than 1 month, viscosity of modified imidazole/epoxy system remains unchanged. The longer chain polyether had the better thermal latency these curing agents had. Compared with unmodified imidazole, the novel latent curing agents led to better impact strength for cured epoxy. However, the compatibility between epoxy and latent curing agent will get worse if the molecular weight of polyether unite is over 750.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 19
·50407
·
IF 2.52
Wentong Gao,Xiao Cao,Menghan Chen,Ke Chen,Shuhang Li,Bing Han
Two tertiary-amine-terminated liquid rubbers (TATPB and TATBN) containing polybutadiene and butadiene acrylonitrile are successfully synthesized and used in the modification of epoxy networks. By taking advantage of the flexibility of rubbers, the toughness of epoxy resin has been significantly improved. The addition of 60 phr TATPB and TATBN increased the impact strength of epoxy resins from 12.2 to 59.8 and 92.0 KJ/m 2 , respectively. Meanwhile, due to the dual role of tertiary amine of TATPB and TATBN in catalysis and curing for epoxies, their T g values shifted from 87.7 to 102.0 and 95.7°C, respectively. TATPB with a smaller polarity improves the toughness of the epoxy resin slightly less than TATBN with a larger polarity, but the former is more effective in increasing the T g values. This study demonstrates a novel strategy to enhance the toughness of epoxy composites as well as improve the high temperature resistance by designing the end-structure of toughening agents.
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高影响因子
危险品化学品经营许可证（带存储）