JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 20
·50416
·
IF 2.52
Shaohua Wang,Ping Yang,Xiangfei Sun,Honglong Xing,Jianjun Shi
A highly-efficient nano-medical carrier system was constructed for drug release based on a facile synthesis, excellent fluorescence, and structure of phenol formaldehyde resin (PFR). The PFR was easily synthesized through a simple one-step hydrothermal reaction, reduction and etching process, and a silane coupling agent modification process. The multiple functionalized drug delivery system, defined as PFR-NH 2 @DOX was constructed by loading Adriamycin (DOX) into PFR. Drug release results in vitro displayed a DOX content of 145 mg g −1 prodrug nanosphere has excellent pH-triggered drug release (about 84.71%) within 72 h at pH 5 solution. The fluorescence recovery of PFR after DOX release indicates the potential application in fluorescence imaging and controlled drug release.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 19
·50403
·
IF 2.52
Meng-Xin Hu,Xian-Lin Chen,Li-Jie Song,Fei He
Arachidonic acid (AA) is an n-6 polyunsaturated 20-carbon fatty acid taking important immunomodulatory roles in infant growth, brain development, and health. However, one of the major drawbacks of polyunsaturated fatty acids is their high susceptibility to oxidation followed by unpleasant odors. Microencapsulation has been proposed as an excellent strategy to solve these problems. In this work, coaxial electrospray was utilized to fabricate AA/zein microcapsules with core-shell structures which were verified by scanning electron microscopy, transmission electron microscopy, and confocal laser scanning microscopy. Microcapsules morphology was conveniently controlled through electrospray parameters and AA was centralized in the core. The microcapsule diameter ranged from 1 to 7 μm. Results of peroxide values and GC–MS demonstrated that AA in microcapsules possess improved oxidative stability and the unpleasant odors of AA oil was inhibited. The results indicate coaxial electrospray is a useful and convenient tool to fabricate core-shell microcapsules with immiscible materials, which will broaden the potential use of microcapsules as nutrition fortifiers in the food industry.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 20
·50413
·
IF 2.52
Zhe Huang,Bo Ruan,Jin Wu,Ning Ma,Tao Jiang,Fang-Chang Tsai
The flame retardant polypropylene containing the micro-envelope core-shell structure flame retardant, which encapsulated ammonium polyphosphate into melamine-formaldehyde resin and sodium silicate through in situ polymerization was prepared with polyamide 6, added as a carbon-forming agent. The composition of ammonium polyphosphate, encapsulated ammonium polyphosphate with melamine-formaldehyde resin and the micro-envelope core-shell structure flame retardant were characterized. The fire safety and thermal stability were investigated and showed an improvement including limiting oxygen index, thermogravimetric analysis, vertical burning tests, and microscale combustion calorimeter. The burned compounds were also studied to confirm the burning mechanism. The results showed the flame retardant performance had been greatly improved, while polyamide 6 had better char-forming effect. Besides, the water solubility of flame retardants and their influence on the mechanical properties of polypropylene were also investigated. The results on the effects of additives demonstrated a high efficiency flame retardant to polypropylene. A core-shell flame retardant that sodium silicate and melamine-formaldehyde resin-coated ammonium polyphosphate had been constructed. The effect of the built flame retardant system on the combustion performance of polypropylene was studied from the mechanism and performance. The LOI of the most flame retardant polypropylene reached 28.6%, and UL-94 reached the V-0 level.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 8
·49872
·
IF 2.52
Wanjie Luo,Lulu Wang,Ruijiang Feng,Chongfeng Zhao,Jilin Wang,Tianzhou Cai
A series of composite anion exchange membranes was synthesized via in-situ copolymerization of various ratios N-vinyl formamide (NVF) and divinylbenzene (DVB), supported by porous polytetrafluoroethylene (PTFE) polymer matrix, and followed by alkaline hydrolysis, and quaternization of the composite membranes with epoxypropyltrimethylammonium chloride (EPTMAC). FTIR and SEM analyses revealed that the composite membranes were successfully prepared. Moreover, the hydrophilic property of the composite membrane improved by introduction of the quaternized poly(NVF-co-DVB) copolymer. Water uptake, swelling ratio, and conductivity showed upward trends by increase of NVF amount. The copolymer with 95% of NVF showed the highest elongation at break (102%, room temperature) and conductivity (5.15 × 10 −2 S/cm, 80°C). After immersion of the PNDB 95% -N membrane in 5 mol/L NaOH solution for 96 h at room temperature, the conductivity (60°C) of the membrane decreased to 3.99 × 10 −2 S/cm. Moreover, the membrane registered weight loss under 4.5%, caused by degradation of the quaternary ammonium groups in NaOH solution. All in all, in 3 mol/L methanol solutions, the composite membranes showed permeability ranging from 7.6% to 19.7%, if compared to the Nafion®-115 membrane, showing good alcohol resistance.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 9
·49907
·
IF 2.52
Junfei Mei,Haoran Geng,Han Yu,Jia Shi,Yanfang Zhao,Rentong Yu,Jianhe Liao,Yongping Chen
Oleylamine (OA) modified silica (SiO 2 -g-OA) was prepared using γ-(2,3-epoxypropoxy) propytrimethoxysilane (KH560) and OA, silica/natural rubber (NR) and SiO 2 -g-OA/NR composites were prepared by mechanical blending in an internal mixer, and SiO 2 -g-OA was characterized by Fourier transform infrared spectroscopy, thermal gravimetric analyzer, and contact angle analyzer. The mechanical properties, abrasion resistance, curing characteristics, Payne effect, and morphology of silica/NR and SiO 2 -g-OA /NR composites were investigated using universal testing machine, Akron abrasion tester, rubber processing analyzer, and scanning electron microscope, respectively. The results showed that SiO 2 -g-OA became more hydrophobic and had better compatibility with NR. Moreover, SiO 2 -g-OA/NR had weaker Payne effect, better vulcanization performance, and more excellent mechanical properties. As the content of filler was more than 30 phr, SiO 2 -g-OA/NR had lower rolling resistance and higher wet skid resistance. Compared with silica modified by other coupling agents, SiO 2 -g-OA had the best reinforcement effect on NR.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 7
·49829
·
IF 2.52
Xu Hu,Jinhao Sun,Xing Li,Lijun Qian,Juan Li
A phosphorus-nitrogen flame retardant (PN) was synthesized by using cytosine and diphenylphosphinic chloride. The flame retardancy and thermal stability of polylactic acid (PLA)/PN composites were investigated by the UL-94 vertical burning test, limited oxygen index (LOI), cone calorimeter test, and thermogravimetric analysis. The PN performs efficiently on improving the flame retardancy of PLA. The PLA composite achieves the UL-94 V-0 rating and its LOI increases to 30.4 vol% by adding 0.5 wt% PN. The flame retardant mechanism analysis showed that PN catalyzes the degradation of PLA to improve the flame retardancy by melting-away mode. Meanwhile PN reduces the release of flammable gasses during thermal degradation of PLA by promoting the transesterification of PLA, which is helpful for extinguishing flame. Moreover, triglycidyl isocyanurate (TGIC) was used as a micro-crosslinking agent to reduce the loss of mechanical properties of PLA/PN composites caused by degradation. Adding 0.1 wt% TGIC and 1.0 wt% PN into PLA, the tensile strength and elongation at break of PLA/PN are increased to the same level as that of PLA. Therefore, PLA with excellent comprehensive performance can be obtained.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 9
·49911
·
IF 2.52
Jian-Ni Liu,Da-Yong Wu,Wei-Hua Liang,Jian-Hua Cao
Achieving excellent thermal stability, good mechanical strength, and low-density in one product, is a big challenge in the design and synthesis of polyimide (PI) foams. We selected a rigid diamine monomer, 2-(4-aminophenyl)-5-aminobenzoxazole (DAPBO) to partially replace 4,4′-oxydianiline (ODA) in BTDA-ODA system, and studied the effect on properties of foamed PI products. With various molar ratio between DABPO and ODA (0:5, 1:4, 2:3, 3:2, 4:1, 5:0), the diamine(s) polymerized with 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (BTDA) and produced six PI precursors (PAE-0 ~ PAE-5). After foaming and thermal imidization, corresponding PI foams (PI-0 ~ PI-5) prepared. Among them, PI-3 has a glass transition temperature of 386°C, which is 95°C higher than PI-0, and its compressive strength reaches 1.32 MPa. Moreover, PI-3 has a uniform cell structure with an average pore size of ~200 μm. The analysis results show that PI-3 is in a transition state from amorphous to partial crystalline, maintaining a balance between flexibility and rigidity. The addition of DABPO not only increases the rigidity of polymer molecular segments, but also introduces N and O atoms that can form intermolecular hydrogen bonds between molecules, which increases the packing density and arrangement regularity of polymer molecules.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 8
·49892
·
IF 2.52
Xianbo Hou,Yan Li,Xiaoguang Luo,Rubing Zhang
Polyimide (PI) aerogels enable promising application in many fields but are always inhibited by their weak resistance to high temperature and low mechanical properties. Herein, novel PI aerogel composites with efficient heat insulation and high compressive performance are prepared by introducing Silicon carbide whiskers (SiC w ) as reinforcement. The SiC w in aerogel function as shrinkage inhibitor and high temperature stabilizer. The addition of SiC w exhibits obvious enhancement and toughening effect, the compressive strength of the PI aerogel composites increases from 1.09 to 1.96 MPa. These PI aerogel composites also show enhanced high temperature stability. The as-prepared PI aerogel composites possess integrated properties of high-temperature resistance, low thermal conductivity, and high compressive strength, which can be the candidate for the application in aerospace.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 137
·期 41
·49250
·
IF 2.52
Ya Li,Cui Cheng,Xiaoran Gao,Siyuan Wang,Hanhui Ye,Xiao Han
Despite aminoglycosides (AGs) have superior antibacterial ability, all approved AGs by FDA are associated with adverse effects such as ototoxicity and nephrotoxicity. To solve these problems, AGs hydrogels based on dynamic covalent bond cross-linking were quickly prepared within 25 s by using AGs, aldehyde hyaluronic acid (A-HA), and adipic acid dihydrazide graft hyaluronic acid (HA-ADH) as materials. FT-IR, thermal analysis, and SEM results exhibited that A-HA/HA-ADH/AGs hydrogels were successfully synthesized with highly porous and interconnected network structure. The water absorption ratio of the hydrogels increased with the decreasing pH and temperature, indicating the hydrogels were pH- and temp-responsive. The pH-dependent degradation also demonstrated pH sensitivity of the hydrogels. Rheology and self-healing analysis assessment displayed that AGs hydrogels had good mechanical property, self-healing ability, and injectability. The hydrogels had no cytotoxicity to L929 cells and their hemolysis ratios were between 0.7% and 1.3%, which reached a nontoxic level. Most importantly, inhibition zones results demonstrated that the hydrogels had excellent and sustained antibacterial performance against Escherichia coli and Staphylococcus aureus . Therefore, A-HA/HA-ADH/AGs hydrogels are potential dressings for wound healing. Further plans including antibacterial and in vivo wound healing assays will be shown in the next work.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 137
·期 39
·49176
·
IF 2.52
Qian Yan,Shujun Zhao,Haijiao Kang,Shifeng Zhang
The development of natural fiber-reinforced composites is environmentally friendly and therefore presents great potential; however, these composites are characterized by poor water resistance and interfacial bonding, which therefore limits its practical applications. This study reported a facile and novel approach for the construction of a high-performance microfibrillated cellulose (MFC) elastomer using thiol-functionalized polyurethane (PU-SH) with the assistance of a bioinspired dopamine platform. This elastomer was then employed as a reactive reinforcer to improve soy protein isolated (SPI) adhesive. The surface modification of MFC included the formation of a polydopamine (PDA) layer and Michael addition reactions between PU-SH and PDA, which were characterized by the Fourier-transform infrared spectroscopy, thermogravimetric analysis, and X-ray photoelectron spectroscopy measurements. It was found that the high-functional MFC elastomer served as a reactive cross-linker that gave rise to multiple physical and chemical interactions with the SPI matrix. This resulted in the optimization of the crosslinking system, which ultimately contributed to the solution of the bottleneck issues for natural fiber-reinforced composites. Consequently, the modified SPI-based adhesives notably enhanced the shear strength to 1.38 MPa, displaying a 236.6% increment compared to the unmodified adhesive. This strategy may provide a new insight into the design and preparation of superior natural plant-reinforced composites.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 137
·期 39
·49185
·
IF 2.52
Zuojun Wei,Haiyan Liu,Linwei Yu,Shuwen Xiao,Yaxin Hou,Xiangrong Chen
Seven delocalized aromatic molecules with electron-donating and electron-withdrawing groups are applied as voltage stabilizers to improve the insulation properties of polyethylene blends. Voltage stabilizers 1 wt% are added into the blends (90 wt% low-density polyethylene and 10 wt% high density polyethylene) by diffusion loading method. Electrical measurements including electrical treeing, space charge distribution, and direct current conductivity are conducted to disclose their effects. The results show that the co-existence of matched electron-donating and electron-withdrawing groups in the molecules is favorable for the insulation properties. A 50% increase of tree initiation voltage is achieved with the addition of 3-aminobenzoic acid, which is also able to inhibit the space charge and decrease the conductivity at lower temperature. Besides, the grafting sample of the optimal molecule is successfully prepared and displayed enhanced electrical properties. Finally, the common internal mechanism of the delocalized molecules on different electrical properties is revealed.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 137
·期 38
·49157
·
IF 2.52
Zhangyu Ma,Linlong Li,Xincui Shi,Zongliang Wang,Min Guo,Yu Wang,Zixue Jiao,Congxiao Zhang,Peibiao Zhang
Polyetheretherketone (PEEK) is a promising bone and dental tissue engineering material with excellent mechanical properties and biocompatibility, but its biological inertness deficiency limits its clinical applications. In this study, poly(sodium p-styrene sulfonate) (pNaSS) was grafted onto PEEK surface by ultraviolet (UV) induced polymerization to enhance its osteogenic activities. Attenuated total reflectance Fourier transformed Infrared (ATR-FTIR) spectroscopy, scanning electron microscopy (SEM), and contact angle (CA) analysis were carried out to prove the success of grafting polymerization. Toluidine blue O (TBO) colorimetric assay was utilized to quantify the graft amounts of pNaSS. Results showed that the amounts of grafted pNaSS on the PEEK surface could be well-controlled from 0.59 ± 0.07 mmol/cm 2 to 5.08 ± 0.20 mmol/cm 2 , through adjusting the UV irradiation time and monomer concentration. The hydrophilicity of PEEK surface was increased and the in vitro mineralization ability was promoted with the introduction of pNaSS. Besides, this surface modification method did not influence the intrinsic mechanical properties of PEEK. in vitro biological studies revealed that cell adhesion, proliferation, and osteogenic differentiation of MC3T3-E1 cells were enhanced with the increase of graft amounts.
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）