JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
·
2012
·Vol. 113
·期 2
·939-945
·
IF 1.604
Chen Yan,Yang Liting,Wu Jiahui,Ma Lijun,Finlow David E.,Lin Shaoquan,Song Keming
A series of new modified epoxy resin (EP) cured products were prepared from epoxidized soybean oil and commercial epoxy resin, with methyl nadic anhydride as curing agent and 1-methylimidazole as promoting agent. The thermal properties of the resins were characterized by DMA and TG; DSC was used to determine the curing process. Fourier transform infrared spectroscopy was utilized to investigate their molecular structures and scanning electron microscopy was used to observe the micro morphology of their impact fracture surfaces. Tensile and impact testing was employed to characterize the mechanical properties of the cured products. The combination of commercial EP with 20 wt% ESO resulted in a bioresin with the optimum set of properties: 130.5 °C T
g , 396.9 °C T
50 % , 74.89 MPa tensile strength, and 48.86 kJ m −2 impact resistance.
研究领域:
高分子材料
·
复合材料科学
·
生物基聚合物
·
材料化学
·
热固性树脂
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2017
·
IF 6.216
Shiyuan Chen,Junheng Zhang,Jiliang Zhou,Daohong Zhang,Aiqing Zhang
A novel hyperbranched polymeric ionic liquid (HBP-AMIM + PF6 − ) was explored via a thiol-ene click reaction using thiol-ended hyperbranched polyesters (THBP) and 1-allyl-3-imethylimidazolium hexafluorophosphate (AMIMPF6). The effects of HBP-AMIM + PF6 − on the curing behavior, mechanical properties and thermal stability of benzoxazine/epoxy thermosets were investigated. The gelation time and differential scanning calorimetry of non-isothermal analysis indicated that the addition of HBP-AMIM + PF6 − significantly decreased the curing temperature of benzoxazine/epoxy thermosets. Simultaneously, the addition of HBP-AMIM + PF6 − also improved the strength, toghness and thermal properties of benzoxazine-epoxy thermosets. The addition of 3 wt% HBP-AMIM + PF6 − -2 could significantly improve the mechanical and thermal performance of thermosets compared with that of cured neat benzoxazine/epoxy resin. The tensile strength, tensile toughness, flexural strength and flexural modulus, impact strength of the thermosets were improved by about 76.6%, 279.3%, 57.8%, 22.3% and 80.4%, respectively, compared with those of cured neat resin. The toughening mechanisms was attributed to the “in situ” reinforcing and toughening mechanism.
研究领域:
高分子材料
·
材料科学
·
热固性树脂
·
复合材料
·
高分子化学
·
功能材料
✓ 已验证
DOI
高影响因子
POLYMER
·
2018
·
IF 3.483
Guodong Zhou,Weitao Wang,Mao Peng
Molecular composites using rigid-rod macromolecules as the reinforcement have attracted tremendous research interest. However, dispersion of rigid-rod macromolecules at molecular level in the matrix remains a great challenge. Herein, we report new epoxy (EP)-based molecular composites with sulfonated aromatic polyamides , poly( p -sulfophenylene terephthalamide) (sPPTA) and poly(benzidine-2,2′-disulfonic acid terephthamide) (PBDT), as the reinforcement, which disperse uniformly in epoxy. Covalent bonds formed by the reaction between the sulfonic acid groups of the polyamides and epoxy prevent reaction-induced phase separation during high temperature curing. The novel molecular composites exhibit extraordinarily high strength and toughness, with maximum tensile strength of sPPTA/EP and PBDT/EP (100.2 ± 4.8 MPa and 121.9 ± 12.5 MPa, respectively) increased by ∼81% and ∼120%, respectively. To the best of our knowledge, the improvement of mechanical properties surpasses those of molecular composites, nanofiller reinforced thermosets and liquid crystalline thermosets ever reported.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2019
·Vol. 26
·期 5
·4997-5007
·
IF 2.914
Zhang Lixin,Rao Lei,Wang Peifang,Guo Xiang,Wang Yuxiong
Herein, we present the preparation of nano-TiO 2 –silicone resin composite films by double liquid phase spray deposition. The films exhibit better adhesion stability and photocatalytic activity under a hydrodynamic erosion condition than conventional nano-TiO 2 composite films. The TiO 2 layer morphology and effective TiO 2 coverage ratio (CR) were affected by the initial curing time (ICT) of the silicone resin, e.g., the increase in an ICT from 10 to 40 min resulted in a CR change from 79.1 to 98.7%. The surface morphology evolution of composite films was studied under a hydrodynamic erosion period of 4 weeks. Obtained results allowed the 4-week evolution to be divided into four stages (pitting, crack pregnant, banded stripping, and surface stripping periods), additionally revealed that the CR of all samples was remained above 65%. The photocatalytic activity of composite films before and after 4-week hydrodynamic erosion was evaluated by rhodamine B degradation experiments. The 4-week erosion only led to the decrease of the photodegradation efficiencies by less than 40% in all cases. Thus, the fabricated TiO 2 –silicone composite films demonstrated excellent durability and photocatalytic activity under the conditions of long-term hydrodynamic erosion, allowing one to conclude that this work paves the way to the fabrication of next-generation photocatalytic materials for industrial applications.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 24
·52368
·
IF 3.057
Xiongfei Zhang,Tianhui Zhao,Ting Cao,Peiyu Liu,Chuang Ma,Pengyun Li,Dang Huang
In this paper, bisphenol A (BPA), epichlorohydrin (ECH), and isocyanate trimer (TDI-T) are used as raw materials to synthesize a high toughness/trimer epoxy resin by graft copolymerization. It was cured at room temperature with low molecular weight polyamide 650 (PA650)/isophorone diamine (IPDA) and low molecular weight polyamide 650/triethylene tetramine (TETA) composite curing system respectively. The cured products of the two compound systems were studied by Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), thermogravimetry (TG), and mechanical property testing. The results show that with the increase of TETA and IPDA curing agents, the heat released during the curing process of the two systems also greatly increases, and the temperature rises from the initial 33.9–69.7°C and 52.8°C. The curing time is shortened from a few days to a few hours, and the controllability of the curing time is effectively realized. When the ratio of triethylene tetramine to low molecular weight polyamide 650 is 2.86:100, the compressive strength is the best, reaching 112.7 MPa, 12% higher than pure polyamide as curing agent, and the specimen can be completely restored to its original shape in a few minutes. When the ratio of TETA to PA650 is 2.86:100, the elongation at break reaches 21.4%.
研究领域:
高分子化学
·
材料科学
·
复合材料
·
热固性树脂
·
功能材料
✓ 已验证
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2018
·
IF 3.741
Yue Han,Donghao Tang,Guangxing Wang,Ying Guo,Heng Zhou,Wenfeng Qiu,Tong Zhao
Low melting phthalonitrile monomers containing allyl and/or methoxyl groups were designed, synthesized and characterized. In order to evaluate their potential application in phthalonitrile resins, these monomers were blended with 1,3-bis(3,4-dicyanophenoxy)benzene and 4-(4-aminophenoxy)phthalonitrile, then cured into polymers. Curing mechanisms of different prepolymers were proposed and compared, and processability, thermal and mechanical properties were characterized. The introduction of methoxyl units was found to postpone the curing, and thermal properties were slightly compromised. On the contrary, the usage of allyl was beneficial to both processability and thermal properties. More importantly, the impact strength for allyl-containing polymers could be as high as 13.63 kJ m −2 , indicating such resin could be applied as high temperature structural composite matrices.
研究领域:
高分子化学
·
材料科学
·
复合材料
·
热固性树脂
·
高性能聚合物
✓ 已验证
DOI
高影响因子
JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
·
2018
·
IF 2.831
Xiaoping Liang,Ping Hu,Hongyang Zhang,Wen Tan
In this work, hypercrosslinked strong anion-exchange polymer resins (HXLPP-SAX) were synthesized and evaluated as solid-phase extraction (SPE) sorbents for extracting fluoroquinolones (FQs) in milk samples. These particles were prepared using a protocol that was facile and cost-effective by combining hypercrosslinking reactions and quaternisation reactions in one step. After the synthesis, the morphological properties and anion-exchange, adsorption, and selectivity performances of the HXLPP-SAX resins were characterized and evaluated. It was shown that the polymers were monodisperse microspheres, with the mean diameters of 2–4 μm, ion-exchange capacity (IEC) of 0.311 meq/g, and specific surface area more than 1000 m 2 /g. The resins applied as SPE sorbents possessed high selectivity in the extraction of amphoteric compounds (enoxacin and enrofloxacin as the representatives) followed by HPLC-UV analysis, as compared to commercially available strong anion-exchange sorbents (Oasis MAX). The SPE-HPLC-UV method was fully validated and exhibited good linearity (10–2000 ng/g, R 2 ≥ 0.997), low limits of detection (2.8–5.1 ng/g), good recoveries (85.8%–117.9%, RSDs ≤ 7.1%) and precisions (intra-day RSDs ≤ 7.7% and inter-day RSDs ≤ 9.4%). Then the method was performed the selective enrichment of six FQs (enoxacin, norfloxacin, ciprofloxacin, lomefloxacin, enrofloxacin, and sparfloxacin) in milk samples. The present results demonstrated that the proposed resins exhibited a promising potential for the enrichment and determination of FQ residues in milk samples as well as in other samples with complex matrices.
研究领域:
分析化学
·
食品科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2020
·
IF 5.065
Jianwei Bai,Xiaofei Ma,Cen Gong,Yiming Chen,Huijun Yan,Kewei Wang,Jun Wang
Traditional adsorption resin prepared by a low efficiency method has a low porosity and surface area , which limits the adsorption performance of the resin. Therefore, a novel porous resin was developed by structural design of the resins through post- modification with HPA and a post-crosslinked method. The novel porous post-modification resin was successfully prepared by the multistep method. Meanwhile, the high surface area and abundant micropores in HCR-AO can improve the adsorption rate by accelerating the diffusion of uranium in the external diffusion stage. The removal capacity of HCR-AO increased 366% for HCR and 120% for PSD-AO at the same initial concentration. HCR-AO takes less time to reach equilibrium than PSD-AO and HCR. Excitingly, the adsorption amount of the material dropped only slightly even after 8 cycles. The short equilibrium time and outstanding removal efficiency makes it a novel candidate for further extraction of U (VI) from seawater .
研究领域:
环境化学
·
核化学
·
材料科学
·
吸附分离
·
海洋资源提取
✓ 已验证
DOI
高影响因子
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
·
2016
·Vol. 122
·期 5
·515
·
IF 1.444
Huang Liang,Zhu Pengli,Li Gang,Sun Rong
The partial reduced graphene oxide (P-rGO) sheets-wrapped nickel foams (NF@P-rGO) were prepared by hydrothermal method, and then their epoxy composites were fabricated via a simple drop-wetting process. The P-rGO sheets on the metal networks could effectively improve the compatibility between nickel foam and epoxy resin, thus greatly accelerate the wetting of epoxy resin on the foams and avoid cracks in the network–polymer interface. Owing to the existence of high-efficiency conductive metal networks, the NF@P-rGO/epoxy composite has a high thermal conductivity of 0.584 W m −1 K −1 , which is 2.6 times higher than that of neat epoxy resin. Additionally, owing to the improved wetting ability, NF@P-rGO-10 wt% boron nitride (BN) microsheets/epoxy composites could be fabricated and have a further higher thermal conductivity of 0.71 W m −1 K −1 . We believe the use of P-rGO as a novel surface modifier and the following liquid polymer drop-wetting could be an effective method to obtain novel and outstanding metal foam/polymer composites.
研究领域:
材料科学
·
高分子复合材料
·
热管理材料
·
表面与界面工程
✓ 已验证
DOI
高影响因子
POLYMER TESTING
·
2021
·
IF 4.282
Tongtong Zhang,Jihuai Tan,Xue Han,Qinghe Fu,Muhua Chen,Yong Xu,Xinbao Zhu
Families of bio-based hyperbranched epoxy (HBPEEs) were successfully prepared using renewable xylitol, bisphenol A and epichlorohydrin as feedstocks. The structure and physical performances of HBPEEs were characterized by FTIR, NMR, GPC and viscosity evaluation. Then, they were used as high efficient tougheners for diglycidyl of bisphenol A/diethylenetriamine (DGEBA/DETA) networks. The results indicated that the incorporation of HBPEEs into the DGEBA system can significantly enhance the mechanical properties and solvent resistance properties of the hybrid (HBPEEs/DGEBA). In particular, toughened hybrids with 15 wt% HBPEE-2 exhibited the outstanding impact strength than that of neat DGEBA (37.4 kJ/m 2 vs. 11.8 kJ/m 2 ) due to its excellent compatibility of with DGEBA. Simultaneously, the ductile fracture morphology of the modified hybrids was also confirmed by SEM. In addition, the activation energies of HBPEE-2/DGEBA hybrids calculated from the non-isothermal curing kinetics were lower than that of neat DGEBA. All of the results suggested that the bio-based HBPEEs could be used as efficient tougheners applied in epoxy resins industry.
研究领域:
高分子化学
·
材料科学
·
绿色化学
·
复合材料
·
聚合物改性
✓ 已验证
DOI
高影响因子
Journal of Materials Research and Technology-JMR&T
·
2023
·
IF 6.4
Jinhui Wang,Ruisong Wang,Xiaoxiao Ji,Chunde Jin,Yutao Yan
Phenol formaldehyde (PF) resin adhesives are widely used in the production of bamboo-based composites owing to their excellent bonding strength and durability. However, the inherent brittleness of cured PF resin may result in notable stress concentration at the interface between PF resin and bamboo bonding, leading to the generation of cracks. In this study, a hyperbranched compound polyethyleneimine (PEI) with high reaction activity was incorporated into a PF resin adhesive to toughen the adhesive and the bonding interface. And the effects of PEI incorporation on the properties of the adhesive and the bonding performance between PF resin and bamboo were comprehensively investigated. The results showed that introduction of flexible PEI chains could effectively facilitated stress transfer, avoiding stress concentration, thus enabling efficient energy release and play a toughening effect. In addition, PEI could react with PF resin and bamboo components during hot pressing, forming a three-dimensional network structure and enhancing the bonding interface, which was proved by FT-IR and XPS analysis. When 1 wt% PEI was incorporated, the bending strength and Charpy impact toughness of the modified PF resin was significantly increased by 38.88% and 76.02%, respectively, compared with the pure PF resin. While the dry and wet shear strength of the bamboo composite bonded by the PEI modified PF resin were also obviously increased. This study is expected to address the problem of cracking in the bonding interface of bamboo composite, and endow the composites with high strength and durability, which can prolong its service life and contribute to the healthy and sustainable development of the bamboo industry.
研究领域:
材料科学
·
木材科学与技术
·
高分子化学
·
复合材料工程
·
胶接与界面科学
✓ 已验证
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2014
·
IF 2.633
Guang-Rui Xu,Miao-Jun Xu,Bin Li
The cyclotriphosphazene-based epoxy resin hexa-[4-(glycidyloxycarbonyl) phenoxy]cyclotriphosphazene defined as CTP-EP was successfully synthesized from hexachlorocyclotriphosphazene, p -hydroxybenzaldehyde and epichlorohydrin. Its chemical structure was characterized by Fourier transform infrared (FTIR) spectroscopy, 1 H NMR, 13 C NMR and 31 P NMR spectroscopy . The prepared compound was cured with diamino diphenyl methane (DDM), diamino diphenyl sulfone (DDS) and m -phenylenediamine (mPDA), respectively. The flame retardant properties, thermal degradation behavior and flame retardant mechanism of the cured CTP-EP were investigated. The LOI values of all cured CTP-EP samples increased from 19.9% for cured diglycidyl ether of bisphenol-A (DGEBA) to above 30% and successfully passed UL-94 V-0 rating, which demonstrated that the prepared CTP-EP thermoset exhibited excellent flame retardancy. The dynamic mechanical thermal analysis (DMA) test demonstrated that the glass transition temperature ( Tg ) enhanced from 155 °C for the cured DGEBA to 167 °C for CTP-EP thermoset . The results of thermogravimetric analysis/infrared spectrometry (TG-IR) tests suggested that the phosphazene group and high aromatic content in CTP-EP thermoset stimulated the dehydration of the matrix at earlier degradation process and the formation of char layer, which retarded the release of pyrolysis gas and enhanced the thermal stability of the cured CTP-EP at high temperature. The cone calorimeter tests (cone) test revealed that heat release rate (HRR), total heat release (THR), smoke production rate (SPR) and total heat production (TSP) of the cured CTP-EP decreased significantly compared with the cured DGEBA. The scanning electron microscopy (SEM) results showed that the phosphazene groups in CTP-EP obviously stimulated the formation of the intumescent, compact and stable char layer, which enhanced the flame retardancy of the matrix during combustion. Consequently, the underlying materials were protected from further degradation and combustion during a fire and result in the efficient flame retardancy of CTP-EP thermoset.
研究领域:
高分子化学
·
材料科学
·
热分析
·
阻燃材料
·
聚合物化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）