Study on modification of epoxy resins with acrylate liquid rubber containing pendant epoxy groups

Abstract The aim of this study was the synthesis of three different epoxy compounds based on naphthalene-2,7-diol (2,7-NAF.EP, 2,7-NAF.WEP, 2,7-NAF.P.EP) and then their cross-linking by triethylenetetramine (TETA). All epoxides were prepared by the reaction of naphthalene-2,7-diol with epichlorohydrin but under different conditions and with other catalysts. The structures of the obtained compounds before and after the cross-linking reactions were confirmed by the attenuated total reflectance Fourier transform infrared spectroscopy (ATR/FT-IR). The ATR/FT-IR spectra of cross-linked compounds show disappearance of the C–O–C bands (about 915 cm−1) derived from the epoxy groups. DSC and TG/DTG measurements indicated that the obtained materials possess good thermal resistance; they are stable up to about 250 °C. The hardness of the cross-linked products was determined using the Shore D method. The highest value of hardness was obtained for the 2,7-NAF.EP-POL. Additionally, the UV–Vis absorption spectra of the obtained polymers were registered and evaluated.

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Fracture Behaviour of Epoxy Resins Modified with Liquid Rubber and Crosslinked Rubber Particles under Mode I Loading

Polymers and Polymer Composites ◽

10.1177/096739111502300605 ◽

2015 ◽

Vol 23 (6) ◽

pp. 399-406

Author(s):

Makoto Imanaka ◽

Keisuke Ikeda ◽

Yoshinobu Nakamura ◽

Masaki Kimoto

Keyword(s):

Epoxy Resins ◽

Fracture Behaviour ◽

Mode I ◽

Liquid Rubber ◽

Rubber Particles ◽

Mode I Loading

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Miscibility, morphology, mechanical, and thermodynamic properties of epoxy resins toughened with functionalized core-shell nanoparticles containing epoxy groups on the surface

Pigment & Resin Technology ◽

10.1108/prt-03-2013-0022 ◽

2013 ◽

Vol 43 (1) ◽

pp. 8-18 ◽

Cited By ~ 2

Author(s):

Xugang Zhang ◽

Bin Zhang ◽

Mingming Sun ◽

Jianhui Li ◽

Lei Wang ◽

...

Keyword(s):

Mechanical Properties ◽

Impact Strength ◽

Thermodynamic Properties ◽

Thermal Resistance ◽

Epoxy Resins ◽

Core Shell ◽

Shell Nanoparticles ◽

Content Type ◽

Core Shell Nanoparticles ◽

Epoxy Groups

Purpose – In order to obtain functionalized core-shell nanoparticles (CSNPs) as excellent toughening agents for epoxy resins. The paper aims to discuss these issues. Design/methodology/approach – Functionalized CSNPs containing epoxy groups on the surface were synthesized by emulsion polymerization with butyl acrylate as the core and methyl methacrylate copolymerizing with glycidyl methacrylate (GMA) as the shell. CSNPs were used as toughening agents for epoxy resins and their chemical structure was characterized by FT-IR. The morphology of modified epoxy networks (MEPN) was analyzed by SEM and TEM. Both the mechanical properties and thermodynamic properties were studied. Findings – The results show that nearly spherical CSNPs with the particle size of 50-100 nm are obtained. A certain amount of CSNPs are uniformly dispersed in epoxy resins by the grinding method and the MEPN shows the ductile fracture feature. The miscibility between CSNPs and epoxy matrix increases with the increase of GMA concentration which makes more bonds form between them. Epoxy resins toughened with 10 wt% CSNPs containing 10 wt% GMA show the best mechanical properties and the increase in tensile strength and impact strength of the MEPN is 13.5 and 59.7 percent, respectively, over the unmodified epoxy networks. And the improvement in impact strength is not accompanied with loss of thermal resistance. Practical implications – The MEPN can be used as high-performance materials such as adhesives, sealants and matrixes of composites. Originality/value – The functionalized CSNPs are novel and it can greatly increase the toughness of epoxy resins without loss of thermal resistance.

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Dynamic mechanical properties and adhesive strengths of epoxy resins modified with liquid rubber. II. Modification with CTBN

Journal of Applied Polymer Science ◽

10.1002/app.1986.070310519 ◽

1986 ◽

Vol 31 (5) ◽

pp. 1351-1362 ◽

Cited By ~ 11

Author(s):

Akio Takemura ◽

Kimihide Shiozawa ◽

Bun-Ichiro Tomita ◽

Hiroshi Mizumachi

Keyword(s):

Mechanical Properties ◽

Epoxy Resins ◽

Dynamic Mechanical Properties ◽

Dynamic Mechanical ◽

Liquid Rubber

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Self-Healing Photocurable Epoxy/thiol-ene Systems Using an Aromatic Epoxy Resin

Advances in Materials Science and Engineering ◽

10.1155/2016/8245972 ◽

2016 ◽

Vol 2016 ◽

pp. 1-11 ◽

Cited By ~ 4

Author(s):

Ricardo Acosta Ortiz ◽

Omar Acosta Berlanga ◽

Aída Esmeralda García Valdez ◽

Rafael Aguirre Flores ◽

José Guadalupe Télles Padilla ◽

...

Keyword(s):

Disulfide Bonds ◽

Epoxy Resins ◽

Room Temperature ◽

Gel Permeation Chromatography ◽

Mechanical Analysis ◽

Hypervalent Iodine ◽

Self Healing ◽

Healing Efficiency ◽

Kinetics Of ◽

Epoxy Groups

A rapid and efficient method to obtain self-healing epoxy resins is discussed. This method is based on the use of a thiol-disulfide oligomer obtained by partial oxidation of a multifunctional thiol using a hypervalent iodine (III) compound as oxidant. The oligomer was characterized by Fourier transform infrared spectroscopy (FTIR), Raman and nuclear magnetic resonance spectroscopies, and gel permeation chromatography (GPC). The oligomer was a joint component of the thiol-ene system along with a tetra-allyl-functionalized curing agent. The kinetics of the photopolymerization of diglycidylether of bisphenol A (DGEBA) revealed that conversions of the epoxy groups as high as 80% were achieved in only 15 minutes by increasing the concentration of the thiol-ene system in the formulation. The disulfide bonds introduced in the copolymer using the thiol-disulfide oligomer allowed the repairing of the test specimens in as little as 10 minutes when the specimens were heated at 80°C or for 500 minutes at room temperature. The analysis of the mechanical properties using dynamic mechanical analysis (DMA) showed that the specimens displayed a healing efficiency up to 111% compared with the unhealed specimens, depending on the amount of polythioethers present in the copolymer.

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Organic Aerogels Based on Epoxy Resins: Synthesis and Properties

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.869.240 ◽

2020 ◽

Vol 869 ◽

pp. 240-245

Author(s):

Alexey Voytik ◽

Georgiy V. Malkov ◽

Artur T. Kapasharov ◽

Alexey Yu. Kostin

Keyword(s):

Infrared Spectroscopy ◽

Epoxy Resin ◽

Epoxy Resins ◽

Supercritical Drying ◽

Curing Conditions ◽

Solvent Content ◽

Bet Method ◽

Catalyst Content ◽

Organic Aerogels ◽

Epoxy Groups

The aim of this work was to develop methods for the synthesis of organic aerogels based on epoxy resins and to investigate their properties. Aerogels based on DGEBA-epoxy resin were obtained by CO2-supercritical drying of gel samples prepared from acetone solutions of epoxy resin with different amount of catalyst and solvents. As a result, aerogels of different density were obtained; the dependence of density on the solvent content in the samples was revealed. The aerogels were characterized by infrared spectroscopy to define the degree of conversion of the epoxy groups, by SEM to confirm nanoscale morphology of aerogels, as well as by the BET method to determine the specific surface area of the samples and its dependence on the catalyst content and curing conditions.

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