POLYMERS FOR ADVANCED TECHNOLOGIES
·
2018
·Vol. 29
·期 8
·2308-2316
·
IF 2.137
Jiahui Zhou,Hanmo Li,Xun Lu
Elastomer is one of the important materials for vibration and noise reduction. However, its narrow effective damping temperature range (tanδ ≥ 0.3) remains to be a major issue that hinders its application as a damping material. Herein, we precisely design and synthesize a polyurethane structure where specific dangling chains with both electron-donating group and electron-absorbing group were introduced into prepolymers, generating more hydrogen bonding interaction with the main chain to hinder microphase separation. At the same time, hyperbranched polyester as a cross-linking agent increases its free volume effectively. The synergy effect of enhancement of hydrogen bonding, decrease of microphase separation, and increase of free volume results in a higher damping polyurethane elastomer with a great wider effective damping temperature range up to 175°C (−60°C-115°C), which provides a new idea for the preparation of damping elastomer.
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DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2013
·Vol. 25
·期 2
·168-172
·
IF 1.635
Li Zhu,Jinmin Qin,Xueqiong Yin,Li Ji,Qiang Lin,Ziyu Qin
Bacterial cellulose (BC) is a form of cellulose synthesized by microorganisms, which has unique structure properties and differs from plant cellulose. Up to now, chemical modification of BC has not been studied widely. This paper aims to prepare sodium bacterial cellulose sulfate (SBS) in N,N-dimethylformamide (DMF) with a ClSO 3 H/DMF complex as the sulfating agent. SBSs with diverse degree of sulfation (DS, 0.04–0.86) were synthesized. The system could change from heterogeneous to homogeneous during the sulfation. Regarding to the DS, the optimal ClSO 3 H amount and reaction time were 6 mol/mol anhydroglucose unit and 4 h, respectively. DS increased a little when increasing the temperature, while the yield decreased significantly. SBSs with DS > 0.24 were soluble in deionized water. Carbon nuclear magnetic resonance spectroscopy revealed that the sulfation prefers to take place in the order of C-6 > C-2 > C-3. The X-ray diffraction profiles indicated that the crystalline structure of BC was destroyed during sulfation. BC has better reactivity than microcrystalline cellulose in both sulfation and depolymerization processes. SBS is a potential biomaterial. However, BC depolymerized obviously in present sulfation, which forbids application of SBS in material. Moisture of the reaction mixture should be removed as completely as possible to guarantee efficient sulfation and decrease depolymerization. Copyright © 2013 John Wiley & Sons, Ltd.
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DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2023
·Vol. 34
·期 6
·1918-1932
·
IF 3.4
Yuqian Du,Xueya Wang,Ziwen Zhou,Feng Zhao,Song Li,Zhihua Liu,Zhengyu Wu,Shuai Zhao,Lin Li
Nowadays, although highly conductive polymer composites filled with two-dimensional graphene-based nano-fillers have been explored extensively, constructing nanocomposites with high performance, industrial feasibility, and more efficient conductive networks at lower nano-filler contents remains a challenge. To achieve the above objectives, industrial wastes microsilica powder (N98) with amorphous spherical structure and large particle size is employed in this work. And the hybrids (TGN) are obtained between N98 and graphene (GE) by the effective bridging and interface coupling of tannic acid, which can achieve the purpose of obtaining conductive composites with low-filler contents by traditional polymer processing technologies. The volume exclusion effect of N98 and its own assisted dispersion effect can prevent and attenuate graphene agglomeration, enabling the formation of a dense, complete and uniform conductive network in natural rubber (NR) matrix based on a small amount of graphene addition (parts per thousand). Thus, it give the nanocomposite highly functional, especially electric property. The results show that when the ratio of GE to N98 hybridization is 1:20, N98 and graphene are more uniformly hybridized together, and the volume exclusion effect is best matched with the rubber composites, and the comprehensive performance is optimal. Moreover, the electrical conductivity of NR/TG 1 N 20 nanocomposite can reach the balanced value of 10 −3 S·cm −1 with the GE loading of 0.48 phr, which shows the effectiveness of the prepared hybrids.
研究领域:
高分子科学
·
纳米复合材料
·
功能高分子
·
材料化学
·
导电聚合物
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DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2011
·Vol. 22
·期 12
·2237-2243
·
IF 1.776
Chenhao Ke,Juan Li,Keyi Fang,Qiliang Zhu,Jin Zhu,Qing Yan
A hyperbranched polyamine was prepared using an A 2 + B 3 approach. It acted as a hyperbranched charring and foaming agent (HCFA) in combination with ammonium polyphosphate (APP) to form a new intumescent flame retardant (IFR) system for polyamide 6 (PA6). Effect of HCFA on flame retardant and thermal degradation properties of IFR-PA6 was investigated by limiting oxygen index (LOI), UL-94 vertical burning, cone calorimeter, and thermogravimetric analysis (TGA) tests. The IFR system presented the most effective flame retardancy in PA6 when the weight ratio of APP to HCFA was 2:1. The LOI value of IFR-PA6 could reach 36.5 with V-0 rating when the IFR loading was 30 wt%. Even if the loading decreased to 25 wt%, IFR-PA6 could still maintain V-0 rating with an LOI value of 31. TGA curves indicated that APP would interact with both PA6 and HCFA in PA6/APP/HCFA composite under heating. The interaction between APP and HCFA improved the char formation ability of IFR system and then much more char was formed for PA6/APP/HCFA composite than for PA6/APP. Therefore, better flame retardancy was achieved. Moreover, the structure and morphology of char residue were studied by Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). The results indicated that compact and foaming char layer containing P-O-C structure was formed for PA6/APP/HCFA system during combustion. Copyright © 2010 John Wiley & Sons, Ltd.
研究领域:
高分子化学
·
材料科学
·
阻燃材料
·
热稳定性
·
聚合物复合材料
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DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2017
·Vol. 29
·期 2
·982-988
·
IF 1.907
Jiayu Xian,Jieting Geng,Yan Wang,Lin Xia
Shape-memory polymers are important smart materials with potential applications in smart textiles, medical devices, and sensors. We prepared trans-1,4-polyisoprene, low-density polyethylene (LDPE), and high-density polyethylene (HDPE) shape-memory composites using a simple mechanical blend method. The mechanical, thermal, and shape-memory properties of the composites were studied. Our results showed that the shape-memory composites could memorize 3 temporary shapes, as revealed by the presence of broad melting transition peaks in the differential scanning calorimetry curves. In the trans-1,4-polyisoprene/LDPE/HDPE composites, the cross-linked network and the crystallization of the LDPE and HDPE portions can serve as fixed domains, and all crystallizations can act as reversible domains. We proposed a schematic diagram to explain the vital role of the cross-linked network and the crystallization in the shape-memory process.
研究领域:
高分子材料科学
·
生物医学工程
·
智能材料
·
功能高分子
·
热响应材料
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DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2017
·Vol. 28
·期 11
·1438-1447
·
IF 1.907
Xin Liu,Xuewen Guo,Yunfei Zhi,Shaoyun Shan,Yonghao Ni,Qingming Jia
The recent development of sulfur dioxide (SO 2 ) polymerization has seen a renaissance in its chemistry, especially poly(olefin sulfone)s from the copolymerization of SO 2 , and unsaturated hydrocarbons can be found to have many applications, including transient electronic packaging, drug delivery, and electron beam-resistant materials. In this work, a type of functional poly(norbornene sulfone) was synthesized via two different polymerization methods. Aiming to understanding the effects of different polymerization methods on poly(olefin sulfone)s and gain further understanding on the kinetics of poly(olefin sulfone)s's thermal instability, we investigated their detailed thermal degradation behaviors using thermogravimetry and analyzed the resultant kinetics in accordance with three kinetic models. The results supported the conclusion that although the poly(norbornene sulfone)s obtained have different activation energy, the thermal degradation kinetics are the same and also obey the D n type. Copyright © 2017 John Wiley & Sons, Ltd.
研究领域:
高分子化学
·
材料科学
·
热分析
·
功能高分子
·
可控降解材料
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DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2020
·Vol. 31
·期 11
·2480-2491
·
IF 2.578
Po Hu,Xinyu Zheng,Jiwei Zhu,Baolin Wu
Chicken feather keratin (CK), a biomaterial that contains a large amount of nitrogen is extracted from chicken feathers and has significant potential for use as a flame retardant. In this study, CK and 9,10-dihydro-9-oxa-10-phosphenanthrene-10-oxide (DOPO) were added in different amounts to an epoxy resin (EP), and their flame retardancy and smoke suppression effects were studied. The results showed that CK exhibits a good flame-retardancy effect and better smoke suppression characteristics than those of DOPO when added to EP. Furthermore, it greatly reduces the CO yield in smoke. While the EP samples with DOPO showed better flame-retardancy properties than those of the samples with CK, they also produced more smoke, which had a higher CO content. Furthermore, when CK and DOPO were added to EP together, the flame-retardancy characteristics of the samples varied with the CK/DOPO ratio. Then the pyrolysis of all samples was divided into two stages based on thermokinetics analysis and the activation energies of these samples in the two stages were investigated. Finally, the flame-retardancy mechanism was discussed. When samples burn, the PO· free radicals derived from DOPO combine with H· and OH· to induce a quenching effect. In addition, the phosphate resulting from the decomposition of DOPO promotes the formation of the char layer. At the same time, the noncombustible gases generated during the pyrolysis of CK cause the char layer to expand and remove some of the heat. Thus, CK and DOPO synergistically improved the flame retardancy of EP.
研究领域:
高分子材料科学
·
阻燃化学
·
热分析
·
环境友好材料
·
生物基添加剂
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DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2017
·Vol. 28
·期 11
·1464-1472
·
IF 1.907
Zhankui Mei,Huanhuan Ren,Shaojun Chen,Zaochuan Ge,Jinlian Hu
This study develops a new type of moisture-sensitive shape memory polymer based on zwitterionic copolymers synthesized with acrylic acid (AA) and 3-Dimethyl (methacryloyloxyethyl) ammonium propane sulfonate (DMAPS). The moisture absorption properties of zwitterionic copolymers are particularly investigated in this paper. The results demonstrate that the DMAPS/AA copolymers possess a sulfobetaine structure and form a two-phase separation structure. The zwitterionic copolymers show both good hydrophilic properties and moisture absorption properties. Both AA and DMAPS segments influence the hydrophilic properties and moisture absorption of the composite copolymer. The moisture absorption process is well modeled by Fick's second law in its initial stage. The moisture absorption is mainly determined by immersion conditions and the given materials' structure. Moisture absorption speed and saturated moisture absorption both increase with an increase in DMAPS content as well as the immersion temperature. The increased moisture absorption rate and higher saturated moisture absorption results from the higher activation energy of diffusion. The DMAPS/AA copolymers demonstrate adequate moisture-sensitive shape memory effects. Stain recovery is faster in the zwitterionic copolymers containing higher DMAPS content, whereas the final shape recovery decreases with an increase of DMAPS content. Finally, it is proposed that not only good moisture absorption units are required but also physical crosslinks should be improved for moisture-sensitive shape memory polymers. Copyright © 2017 John Wiley & Sons, Ltd.
研究领域:
高分子材料科学
·
功能高分子
·
智能响应材料
·
生物医用材料
·
软物质物理
·
环境响应材料
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DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2016
·Vol. 27
·期 11
·1501-1507
·
IF 1.823
Zhubo Liu,Bing Zhou,A.V. Rogachev,M.A. Yarmolenko
Polytetrafluoroethylene (PTFE) composite coatings doped copper acetate and polyurethane (PU) were prepared on rubber substrate by low-energy electron beam dispersion technique. The effects of dopant and glow discharge treatment on the surface morphology, structure and tribological properties of the coatings were investigated. The results showed that Cu–PTFE composite coatings form uniform surface and dense column structure with spherical aggregations under glow discharge treatment. PU coating shows the large size of protuberance structure but PU–PTFE coating presents spherical structure. Both of the coatings become relative dense and smooth after discharge treatment, and Cu–PU–PTFE composite coatings possess a smoother surface and lower polar component of surface energy. Cu doping weakens the crystallinity and ordering degree of composite coatings, but glow discharge increases the ordering degree and branched structure of C―H groups. Friction experiment indicated that Cu fails to improve the wear resistance of PTFE coatings but glow discharge treatment can do it. Cu–PU–PTFE coatings after discharge treatment have the higher wear resistance and lower coefficient of friction. Copyright © 2016 John Wiley & Sons, Ltd.
研究领域:
材料科学
·
表面工程
·
高分子材料
·
摩擦学
·
等离子体物理
·
涂层技术
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DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2017
·Vol. 29
·期 1
·463-469
·
IF 1.907
Xiaoxia Jian,Yiwen Hu,Weiliang Zhou,Leqin Xiao
Tough and transparent polyurethane networks with self-healing capability at mild temperature conditions were successfully prepared in a 1-pot procedure. The self-healing ability of synthesized polyurethane comes from the covalent disulfide metathesis and non-covalent H-bonding. The mechanical testing indicates that disulfide metathesis reforms the covalent bonds on a longer time scale, while H-bonding gives rise to a healing efficiency of around 46% in the early healing processing. The compromise between mechanical performance and healing capability is reached by tailoring the concentration of disulfide. The tensile strength of the sample with 100% self-heal efficiency can get to 5.01 MPa, which can be explained by higher mobility of polymer chain under ambient temperature from creep testing.
研究领域:
高分子材料科学
·
功能材料
·
软物质物理
·
化学工程
·
纳米复合材料
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DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2019
·Vol. 30
·期 11
·2781-2789
·
IF 2.162
Tingjun Zhong,Richard J. Mandle,John W. Goodby,Lanying Zhang,Cuihong Zhang
In this work, the thiol-ene click reaction is employed to fabricate polymer-dispersed liquid crystal (PDLC) films by photoinitiated polymerization. The PDLC films are prepared by systematic variation of key conditions: variety and content of -ene monomer, liquid crystal (LC) content, curing time, and curing light intensity. We find that both the morphologies and electro-optic properties of these films are adjustable. When increasing the length of alkyl main chain of -ene monomers, the driving voltages reduce, but in turn, the contrast ratio decreases. Increasing -ene monomer content raises the driving voltages as well as the response time, and the increase of LC content lowers the driving voltages but has a negative effect on the contrast ratio. The changes to the curing conditions (both curing time and UV light intensity) can be used to modify the driving voltages, response time, and contrast ratios of PDLC films. These comparative studies will elucidate new insights in commercial applications of intelligent PDLC films.
研究领域:
材料科学
·
高分子化学
·
软物质物理
·
光电功能材料
·
智能材料
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DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2018
·Vol. 29
·期 12
·2982-2991
·
IF 2.137
Zhiyong Zhang,Miaojun Xu,Bin Li
The polymethacrylimide/silicate (PMI/silicate) composites were successfully prepared from the monomers of acrylonitrile (AN) and methacrylic acid (MAA) via the monomer in situ intercalation polymerization and free foaming. The formation of imide groups was monitored by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The results of FTIR and XPS indicated that the imide groups were gradually formed and cyano groups were dwindling but still existed during foaming and thermal treatment. The thermogravimetric analysis results revealed that the thermal stability of the PMI/silicate composites was improved, the rate of thermal degradation was reduced, and the residue was increased because of the addition of silicates. The results of dynamic mechanical analysis revealed that the rigidity and the glass transition temperature of the composites were improved. The limit oxygen index (LOI) and cone calorimeter (CONE) test showed that the fire-retardant properties were improved because of the barrier effect of silicates. The cell morphologies of the PMI/silicate composites were characterized by scanning electron microscopy (SEM), and the results showed that the silicate particles were distributed on the cell walls, but the cells slightly cracked. The mechanical properties were measured by tensile, flexural, and compressive strength. The mechanical strength, especially flexural strength, was significantly improved. The flexural strength of PMI/MMT, PMI/kaolin, and PMI/talc containing 8 wt% silicates was improved to 172%, 240%, and 233%.
研究领域:
高分子材料
·
复合材料科学
·
材料化学
·
防火材料
·
多孔材料
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DOI
高影响因子
危险品化学品经营许可证（带存储）