Applied Research of the Flexible Epoxy Resin Curing Agent

2012 ◽  
Vol 535-537 ◽  
pp. 2499-2502
Author(s):  
X. Wang ◽  
S. R. Zheng ◽  
R. M. Wang
Keyword(s):  
Mechanical Properties ◽  
Fracture Toughness ◽  
Fracture Surface ◽  
Epoxy Resin ◽  
Epoxy Resins ◽  
Applied Research ◽  
Curing Agent ◽  
Structural Adhesives ◽  
Resin Curing ◽  
The Impact

Epoxy resin structural adhesives modified by flexible curing agent. Dependening on the mechanical properties of epoxy resins on the flexible curing agent content was studied. The impact fracture toughness was discussed in terms of fracture surface fractography.

Studies on Mechanical and Thermal Properties of Epoxy Resin Modified by Fluorine-Containing Silicone

2013 ◽  
Vol 401-403 ◽  
pp. 713-716
Author(s):  
Cheng Fang ◽  
Dong Bo Guan ◽  
Wei Guo Yao ◽  
Shou Jun Wang ◽  
Hui An
Keyword(s):  
Glass Transition ◽  
Thermal Properties ◽  
Epoxy Resin ◽  
Bending Strength ◽  
Mechanical And Thermal Properties ◽  
Curing Agent ◽  
Epoxy System ◽  
Resin Curing ◽  
The Impact ◽  
Modified Epoxy

The epoxy resin was modified with the mixture of α,ω-dihydroxy poly-(3,3,3-trifluoropropyl) siloxane (PTFPMS), KH560 and stannous octoate. KH560 can react with PTFPMS and also epoxy resin curing agent. The two reactions were characterized by FI-IR. The modified epoxy resin was characterized by FI-IR. The result showed that fluorine-containing silicone had been successfully introduced into the epoxy system. The mechanical and thermal properties of the modified epoxy resin were analyzed. The results showed that with the increase of PTFPMS the impact strength of epoxy resin increased, hardness and bending strength correspondingly reduced, slight decrease in the glass transition temperature.

Research on Synthesis and Properties of a Flexible Epoxy Curing Agent

2015 ◽  
Vol 744-746 ◽  
pp. 1463-1466
Author(s):  
Xi Wang
Keyword(s):  
Fracture Toughness ◽  
Impact Toughness ◽  
Epoxy Resin ◽  
Curing Agent ◽  
Pure Epoxy ◽  
Epoxy Curing ◽  
New Type ◽  
The Impact

This paper presents the synthesis of a new type of flexible epoxy curing agent and an approach to improve the toughness of epoxy resin by curing without reducing the strength and modulus of the resin-cured material. The results show that the degree of toughness reaches maximum values when the flexible curing agent is applied at weight percentages (wt.%) between 10% and 15%. When the amount of flexible curing agent added to epoxy resin weight is 10wt.%, the impact toughness and fracture toughness increases by 33.3% and 96.3%, respectively, compared with the pure epoxy resin. When the amount of flexible curing agent added to epoxy is 10wt.%, the resulting impact thoughness of the material is 19.5 kJ•m-2 at-50°C, the impact toughness of pure epoxy resin is only 7.96 kJ•m-2.

Solvent Exchange to Exfoliate Graphene Oxides into Epoxy with Improved Mechanical and Thermal Properties

2015 ◽  
Vol 1110 ◽  
pp. 69-72
Author(s):  
Fu Ke Wang ◽  
Chao Bin He
Keyword(s):  
Mechanical Properties ◽  
Epoxy Resin ◽  
Epoxy Resins ◽  
Mechanical And Thermal Properties ◽  
Curing Agent ◽  
Solvent Exchange ◽  
Thermal And Mechanical Properties ◽  
Graphene Oxides ◽  
Curing Agents ◽  
Exchange Technique

The dispersion and exfoliation of graphene oxides in polymer matrix remains a challenge for graphene oxides based epoxy nanocomposites fabrication. In the present paper, we reported a simple and facile solvent exchange technique to successfully transfer graphene oxides (GOs) from aqueous solution to ethanol. In addition, we found that GO dispersion in epoxy resins was affected by the curing agents. Good dispersion of GOs in epoxy resin together with enhanced thermal and mechanical properties were observed when epoxy was cured with aliphatic curing agents. For aromatic curing agent, high loading of GOs leaded to GOs aggregation, but well dispersed GOs was observed at low loading of GOs. Especially, a 12 °C increase of glass transition temperature of the epoxy resin was observed with only 0.1 wt% GOs was added to the epoxy resin.

Study on a Novel Soften Curing Agent for Toughening Epoxy Resins

2012 ◽  
Vol 557-559 ◽  
pp. 224-227
Author(s):  
Chun Hua Lou ◽  
Jian Xin Wang ◽  
Li Qun Ma ◽  
Zhao Hui Chen
Keyword(s):  
Mechanical Properties ◽  
Epoxy Resins ◽  
Epoxy Group ◽  
Curing Agent ◽  
Butyl Ether ◽  
Ft Ir ◽  
Ir Analysis ◽  
The Impact ◽  
Better Than ◽  
Phenylene Diamine

A new soften curing agent for toughening epoxy resins was synthesized by m-phenylene diamine modified with epoxypropyl butyl ether. Fourier transform infrared (FT-IR) analysis showed that the longer the reaction time was, the smaller the absorption peaks of epoxy group were. The results of the mechanical properties demonstrated that the impact property of the epoxy resin cured by modified m-phenylene diamine at the moderate temperature was better than that of cured by un-modified one because of the introduction of soft ether chain.

Preparation and mechanical properties of thermosetting epoxy foams based on epoxy/ 2-ethyl-4-methylimidazol system with different curing agent contents

2017 ◽  
Vol 53 (6) ◽  
pp. 663-681 ◽  
Author(s):  
Jiantong Li ◽  
Guangcheng Zhang ◽  
Xiaolong Fan ◽  
Xun Fan ◽  
Lisheng Zhou ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Epoxy Resin ◽  
Epoxy Resins ◽  
Tensile Modulus ◽  
Crosslinking Density ◽  
Curing Agent ◽  
Foaming Process ◽  
Lower Tensile Strength ◽  
Scanning Electron ◽  
Thermosetting Epoxy

Epoxy/2-ethyl-4-methylimidazol system with different curing agent content was completely cured for foaming, and the effect of a systematic variation in 2-ethyl-4-methylimidazol content on the crosslinking density of cured epoxy resins was investigated. It was found that the crosslinking density of completed cured epoxy reduced as the 2-ethyl-4-methylimidazol content increased in certain range of contents (10–50 mol%). Then the precursors were foamed by a batch foaming process with supercritical carbon dioxide. The cellular morphologies of foamed epoxy resins were analyzed by scanning electron microscopy. The results revealed that the reduced crosslinking density would improve the foamability of cured epoxy resin. The microcellular epoxy foams could be obtained by maintaining a moderate crosslinking density, which can be controlled by varying 2-ethyl-4-methylimidazol content. For the completely cured epoxy with different curing agent content, when the crosslinking density of epoxy resin was 232.40 mol m–3 (the 2-ethyl-4-methylimidazol content was 35 mol%) or lower, microcellular structure was obtained by adjusting the foaming conditions. The effects of foaming on the mechanical properties were also discussed. The results indicated that microcellular epoxy foams had higher impact strength but lower tensile strength and tensile modulus, validating that the introduction of microcellular structure in epoxy matrix was conducive to the improvement of the ductility of epoxy foams.

The Mechanical Properties of Organic Modified Epoxy Resin

2020 ◽  
Vol 43 (3) ◽  
pp. 10-14
Author(s):  
Georgel MIHU ◽  
Claudia Veronica UNGUREANU ◽  
Vasile BRIA ◽  
Marina BUNEA ◽  
Rodica CHIHAI PEȚU ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Composite Materials ◽  
Epoxy Resin ◽  
Epoxy Matrix ◽  
Epoxy Resins ◽  
Mechanical Tests ◽  
Organic Modification ◽  
Three Point Bending ◽  
Modified Epoxy

Epoxy resins have been presenting a lot of scientific and technical interests and organic modified epoxy resins have recently receiving a great deal of attention. For obtaining the composite materials with good mechanical proprieties, a large variety of organic modification agents were used. For this study gluten and gelatin had been used as modifying agents thinking that their dispersion inside the polymer could increase the polymer biocompatibility. Equal amounts of the proteins were milled together and the obtained compound was used to form 1 to 5% weight ratios organic agents modified epoxy materials. To highlight the effect of these proteins in epoxy matrix mechanical tests as three-point bending and compression were performed.

scholarly journals An Effective Method for Preparation of Liquid Phosphoric Anhydride and Its Application in Flame Retardant Epoxy Resin

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2205
Author(s):  
Qian Li ◽  
Yujie Li ◽  
Yifan Chen ◽  
Qiang Wu ◽  
Siqun Wang
Keyword(s):  
Flame Retardant ◽  
Epoxy Resin ◽  
Epoxy Resins ◽  
Oxygen Index ◽  
Decomposition Temperature ◽  
Ease Of Use ◽  
Limiting Oxygen Index ◽  
Good Thermal Stability ◽  
Low Viscosity ◽  
The Impact

A novel liquid phosphorous-containing flame retardant anhydride (LPFA) with low viscosity was synthesized from 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and methyl tetrahydrophthalic anhydride (MeTHPA) and further cured with bisphenol-A epoxy resin E-51 for the preparation of the flame retardant epoxy resins. Both Fourier transform infrared spectroscopy (FT-IR), mass spectrometry (MS) and nuclear magnetic resonance (NMR) measurements revealed the successful incorporation of DOPO on the molecular chains of MeTHPA through chemical reaction. The oxygen index analysis showed that the LPFA-cured epoxy resin exhibited excellent flame retardant performance, and the corresponding limiting oxygen index (LOI) value could reach 31.2%. The UL-94V-0 rating was achieved for the flame retardant epoxy resin with the phosphorus content of 2.7%. With the addition of LPFA, the impact strength of the cured epoxy resins remained almost unchanged, but the flexural strength gradually increased. Meanwhile, all the epoxy resins showed good thermal stability. The glass transition temperature (Tg) and thermal decomposition temperature (Td) of epoxy resin cured by LPFA decreased slightly compared with that of MeTHPA-cured epoxy resin. Based on such excellent flame retardancy, low viscosity at room temperature and ease of use, LPFA showed potential as an appropriate curing agent in the field of electrical insulation materials.

Effect of toughened polyamide-coated carbon fiber fabric on the mechanical performance and fracture toughness of CFRP

2021 ◽  
pp. 002199832199945
Author(s):  
Jong H Eun ◽  
Bo K Choi ◽  
Sun M Sung ◽  
Min S Kim ◽  
Joon S Lee
Keyword(s):  
Mechanical Properties ◽  
Fracture Toughness ◽  
Photoelectron Spectroscopy ◽  
Mechanical Performance ◽  
Epoxy Composites ◽  
Scanning Calorimetry ◽  
Internal Damage ◽  
Impact Tests ◽  
Flexural Tests ◽  
The Impact

In this study, carbon/epoxy composites were manufactured by coating with a polyamide at different weight percentages (5 wt.%, 10 wt.%, 15 wt.%, and 20 wt.%) to improve their impact resistance and fracture toughness. The chemical reaction between the polyamide and epoxy resin were examined by fourier transform infrared spectroscopy, differential scanning calorimetry and X-ray photoelectron spectroscopy. The mechanical properties and fracture toughness of the carbon/epoxy composites were analyzed. The mechanical properties of the carbon/epoxy composites, such as transverse flexural tests, longitudinal flexural tests, and impact tests, were investigated. After the impact tests, an ultrasonic C-scan was performed to reveal the internal damage area. The interlaminar fracture toughness of the carbon/epoxy composites was measured using a mode I test. The critical energy release rates were increased by 77% compared to the virgin carbon/epoxy composites. The surface morphology of the fractured surface was observed. The toughening mechanism of the carbon/epoxy composites was suggested based on the confirmed experimental data.

scholarly journals Effect of Secondary Carbon Nanofillers on the Electrical, Thermal, and Mechanical Properties of Conductive Hybrid Composites Based on Epoxy Resin and Graphite

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4169
Author(s):  
Marcel Zambrzycki ◽  
Krystian Sokolowski ◽  
Maciej Gubernat ◽  
Aneta Fraczek-Szczypta
Keyword(s):  
Mechanical Properties ◽  
Specific Surface ◽  
Epoxy Resin ◽  
Surface Area ◽  
Specific Surface Area ◽  
Hybrid Composites ◽  
Department Of Energy ◽  
Carbon Nanofillers ◽  
The Impact ◽  
Secondary Carbon

In this work, we present a comparative study of the impact of secondary carbon nanofillers on the electrical and thermal conductivity, thermal stability, and mechanical properties of hybrid conductive polymer composites (CPC) based on high loadings of synthetic graphite and epoxy resin. Two different carbon nanofillers were chosen for the investigation—low-cost multi-layered graphene nanoplatelets (GN) and carbon black (CB), which were aimed at improving the overall performance of composites. The samples were obtained by a simple, inexpensive, and effective compression molding technique, and were investigated by the means of, i.a., scanning electron microscopy, Raman spectroscopy, electrical conductivity measurements, laser flash analysis, and thermogravimetry. The tests performed revealed that, due to the exceptional electronic transport properties of GN, its relatively low specific surface area, good aspect ratio, and nanometric sizes of particles, a notable improvement in the overall characteristics of the composites (best results for 4 wt % of GN; σ = 266.7 S cm−1; λ = 40.6 W mK−1; fl. strength = 40.1 MPa). In turn, the addition of CB resulted in a limited improvement in mechanical properties, and a deterioration in electrical and thermal properties, mainly due to the too high specific surface area of this nanofiller. The results obtained were compared with US Department of Energy recommendations regarding properties of materials for bipolar plates in fuel cells. As shown, the materials developed significantly exceed the recommended values of the majority of the most important parameters, indicating high potential application of the composites obtained.

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