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.

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.

Impact of Chemical Modification on the Physical and Mechanical Properties of Tropical Wood Material

2012 ◽  
Vol 576 ◽  
pp. 314-317
Author(s):  
Sinin Hamdan ◽  
M. Saiful Islam
Keyword(s):  
Mechanical Properties ◽  
Diazonium Salt ◽  
Treated Wood ◽  
Coupling Reaction ◽  
Physical And Mechanical Properties ◽  
Modulus Of Rupture ◽  
Ft Ir ◽  
Ir Analysis ◽  
D Values ◽  
Benzene Diazonium

Five types of selected tropical light hardwoods were chemically modified with benzene diazonium salt to improve their physical and mechanical properties. Benzene diazonium salt underwent a coupling reaction with wood which was confirmed through FT-IR analysis. The compressive modulus of the treated wood increased, whereas modulus of rupture was shown to decrease on treatment. The modified wood samples had higher hardness (Shore D) values compared to that of the control ones.

scholarly journals Effect of Intercalation Structure of Organo-Modified Montmorillonite/Polylactic Acid on Wheat Straw Fiber/Polylactic Acid Composites

Polymers ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 896 ◽  
Author(s):  
Qiqi Fan ◽  
Guangping Han ◽  
Wanli Cheng ◽  
Huafeng Tian ◽  
Dong Wang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Thermogravimetric Analysis ◽  
Wheat Straw ◽  
Polylactic Acid ◽  
Low Cost ◽  
Interlayer Spacing ◽  
Positive Influence ◽  
X Ray Diffraction ◽  
Ft Ir ◽  
Ir Analysis

In this work, an easy way to prepare the polylactic acid (PLA)/wheat straw fiber (WSF) composite was proposed. The method involved uses either the dopamine-treated WSF or the two-step montmorillonite (MMT)-modified WSF as the filler material. In order to achieve the dispersibility and exfoliation of MMT, it was modified by 12-aminododecanoic acid using a two-step route. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were performed to characterize the modified MMT and the coated WSF. As for the properties of PLA/WSF composites, some thermal (using Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis) and mechanical properties (flexural, tensile, and impact) were analyzed. The results showed that the dopamine was successfully coated onto the WSF. Furthermore, Na-MMT was successfully transformed to organo-montmorillonite (OMMT) and formed an exfoliated structure. In addition, a better dispersion of MMT was obtained using the two-step treatment. The interlayer spacing of modified MMT was 4.06 nm, which was 123% higher than that of the unmodified MMT. Additionally, FT-IR analysis suggested that OMMT diffused into the PLA matrix. The thermogravimetric analysis (TGA) showed that a higher thermal stability of PLA/WSF composites was obtained for the modified MMT and dopamine. The results also showed that both the dopamine treated WSF and the two-step-treated MMT exhibited a positive influence on the mechanical properties of PLA/WSF composites, especially on the tensile strength, which increased by 367% compared to the unmodified precursors. This route offers researchers a potential scheme to improve the thermal and mechanical properties of PLA/WSF composites in a low-cost way.

scholarly journals Transcrystallization of Isotactic Polypropylene/Bacterial Cellulose Hamburger Composite

Polymers ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 508 ◽  
Author(s):  
Bo Wang ◽  
Fu-hua Lin ◽  
Xiang-yang Li ◽  
Xu-ran Ji ◽  
Si-xiao Liu ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Bacterial Cellulose ◽  
Isotactic Polypropylene ◽  
Crystallization Rate ◽  
Sem Analysis ◽  
Hydroxyl Groups ◽  
Hot Press ◽  
Ft Ir ◽  
Ir Analysis ◽  
The Fourier Transform

Isotactic polypropylene (iPP) is a commonly used thermoplastic polymer with many excellent properties. But high brittleness, especially at low temperatures, limits the use of iPP. The presence of transcrystallization of iPP makes it possible for fiber-reinforced iPP composites with higher strength. Bacterial cellulose (BC) is a kind of cellulose with great potential to be used as a new filler to reinforce iPP due to its high crystallinity, biodegradability and efficient mechanical properties. In this study, the iPP/BC hamburger composite was prepared by a simple hot press and maleic anhydride grafted polypropylene (MAPP) was used to improve the interface compatibility of iPP and BC. The polarizing microscope (POM) photograph shows that BC successfully induces the transcrystallization of iPP. The differential Scanning Calorimeter (DSC) date proves that the addition of BC could improve the thermal properties and crystallization rate of the composite. Especially, this change is more obvious of the iPP/MAPP/BC. The mechanical properties of the iPP/BC composites were greatly increased. This DSC date is higher than BC; we used BC particles to enhance the iPP in our previous research. The scanning Electron Microscope (SEM) analysis intuitively shows that the interface of the iPP/MAPP/BC is more smooth and flat than the iPP/BC. The fourier Transform infrared spectroscopy (FT-IR) analysis of the iPP/BC hamburger composites was shown that a new C=O group vibration appeared at 1743 cm−1, which indicated that the hydrogen bond structure of BC molecules was weakened and some hydroxyl groups were substituted after modification which can increase the lipophilicity of BC. These results indicated that the BC fiber can easily induce the transcrystallization of iPP, which has excellent mechanical properties. Moreover, the addition of MAPP contributes greatly to the interface compatibility of iPP and BC.

Effect of Various Curing Agents On the Chemical Stability of Epoxy Resins

CORROSION ◽  
1961 ◽  
Vol 17 (1) ◽  
pp. 11t-20t ◽  
Author(s):  
RONALD L. DeHOFF
Keyword(s):  
Molecular Weight ◽  
Chemical Stability ◽  
Epoxy Resins ◽  
Room Temperature ◽  
Low Molecular Weight ◽  
Curing Agent ◽  
Corrosion Prevention ◽  
Curing Agents ◽  
Outdoor Weathering ◽  
Better Than

Abstract The epoxy resins most widely used in corrosion prevention are liquids of low molecular weight which can be converted to hard, tough, chemically resistant polymers by the use of various curing agents. Unlike other thermosetting resins such as polyesters, the curing agents may produce chemical linkages in the final polymers that differ from those present in the uncured form. Hence, the properties of cured epoxy resins are likely dependent upon, and may even reflect the properties of the curing agent used. Some seven different epoxy resin systems were exposed to various chemical environments and evaluatd for changes in dimensional stability and flexural strengths over a six month period. From the data presented herein, only limited conclusions may be drawn. Heat cured systems fare better than room temperature cured systems in every case. Anhydride cured epoxy resins show greater resistance to outdoor weathering than amine cured systems. 5.4.5, 6.6.8

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.

Curing behavior, thermal, and mechanical properties of epoxy resins cured with a novel liquid crystalline dicarboxylic acid curing agent

2013 ◽  
Vol 54 (3) ◽  
pp. 695-703 ◽  
Author(s):  
Le Hoang Sinh ◽  
Nguyen Ngoc Trung ◽  
Bui Thanh Son ◽  
Seunghan Shin ◽  
Dinh Tan Thanh ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Dicarboxylic Acid ◽  
Epoxy Resins ◽  
Liquid Crystalline ◽  
Curing Agent ◽  
Thermal And Mechanical Properties ◽  
Curing Behavior

scholarly journals Methodological Aspects of Obtaining and Characterizing Composites Based on Biogenic Diatomaceous Silica and Epoxy Resins

Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4607
Author(s):  
Marta Dobrosielska ◽  
Renata Dobrucka ◽  
Dariusz Brząkalski ◽  
Michał Gloc ◽  
Janusz Rębiś ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Epoxy Resins ◽  
Diatomaceous Earth ◽  
Optical Microscope ◽  
Filler Concentration ◽  
Large Area ◽  
Diatomaceous Silica ◽  
Guidelines And Recommendations ◽  
The Impact

Diatomaceous earth are sediments of unicellular algal skeletons with a well-defined hierarchical structure. Despite many tests conducted on systems using diatomaceous earth and epoxy resins, we can find many differences in the methods of acquisition and characteristics of the composite, which may considerably affect the results. In our study, we have conducted tests to verify the impact of the method of obtaining samples and the degassing of the composite on its mechanical properties and standard deviation. The samples were cast in glass moulds and silicone moulds and then subjected to testing for their mechanical and functional properties, imaging with the use of an optical microscope and a scanning electron microscope. The tests have shown that, for samples cast in glass moulds, there is no heterogeneity within the area of the tested sample, as in the case of samples cast in silicone moulds. Silicone moulds allow for quite effective self-degassing of the resin due to the large area-to-mass ratio, and the small remaining air vesicles have a limited effect on the mechanical properties of the samples. The filler used also played a significant role. For systems containing base and rinsed diatomite, it is clear that the degassing of mixtures increases the tensile strength. For treated diatomite, the elongation at break grew along with increasing filler concentration, while for base diatomite, the improvement was observed for flexural strength and impact strength. A non-modified epoxy resin shows a tensile strength at 19.91 MPa (silicone mould cast). At the same time, the degassed, glass mould-cast systems containing 12% of base and rinsed diatoms showed a tensile strength of 27.4 MPa and 44.7 MPa, respectively. We have also observed that the higher the filler concentration, the higher were the tensile strength values, which for the rinsed diatoms reached over 55.1 MPa and for the base diatoms were maximum of 43.8 MPa. The tests, therefore, constitute a set of guidelines and recommendations for testing with the use of fillers showing an extended inner structure.

scholarly journals Influence of Commercial Biochar Fillers on Brittleness/Ductility of Epoxy Resin Composites

2019 ◽  
Vol 9 (15) ◽  
pp. 3109 ◽  
Author(s):  
Mattia Bartoli ◽  
Mauro Giorcelli ◽  
Carlo Rosso ◽  
Massimo Rovere ◽  
Pravin Jagdale ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Epoxy Resins ◽  
Sem Analysis ◽  
Resin Composites ◽  
Neat Resin ◽  
Reinforced Plastics ◽  
Ft Ir ◽  
Epoxy Resin Composites ◽  
Selective Enhancement ◽  
The Relationship

Production of versatile composites is a very attractive field. Carbon containing epoxy resins are one of the most relevant reinforced plastics used for a wide number of applications. In this research, we studied the influence of five different commercial biochar samples for the selective enhancement of brittleness and ductility of an epoxy based composite. We proved the relationship between biochar morphology and composites mechanical properties with the aid of FT-IR and FE-SEM analysis. We were able to improve the neat resin mechanical properties by doubling its Young’s modulus and ultimate tensile strength using a wheat straw derived material, and to increase its elongation by 40%, we used a Miscanthus derived biochar.

The Influence of Functionalized TiO2 with Poly(methyl methacrylate) on the Mechanical Properties of TiO2/Epoxy Nanocomposites

2011 ◽  
Vol 415-417 ◽  
pp. 297-301
Author(s):  
Hong Bo Liang ◽  
Lei Xiong ◽  
Hai Tao Xu ◽  
Jing Guan
Keyword(s):  
Mechanical Properties ◽  
Methyl Methacrylate ◽  
Bending Strength ◽  
Impact Testing ◽  
Epoxy Composites ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
1H Nuclear Magnetic Resonance ◽  
Ft Ir ◽  
The Impact

The functionalized TiO2 with poly(methyl methacrylate) (TiO2-PMMA) was prepared by atom transfer radical polymerization (ATRP), and its reinforcement for epoxy composites was studied. The functionalized TiO2 was characterized by Fourier transform infrared (FT-IR), Thermal gravimetric analysis (TGA) and 1H nuclear magnetic resonance (NMR). The properties of nanocomposites were measured by impact testing, bending experiment and Scanning electron microscopy (SEM). Because of the grafting of PMMA and the higher interaction between TiO2-PMMA and epoxy matrix, the composites exhibited the enhancement of mechanical properties at lower content. As the functionalized TiO2 content is 0.5 wt%, the impact strength and bending strength of composite increased nearly 142% and 37%, respectively, compared to the neat epoxy resin.

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