Study of dextrin-derived curing agent for waterborne epoxy adhesive

With chemical modification method, the epoxy resin E44 was modified into water-borne epoxy resin by diethanolamine, considering the compatibility of curing agent and resin, diethylenetriamine was modified into epoxy amine curing agent as well, through single factor method to discuss the effects of reactant ratio, reaction temperature on the results of the product, the structure of the product was analyzed by Infrared spectrum. The experimental results showed that, when molar ratio of epoxy resin and diethanolamine was 4:3, reaction temperature of 70-80°C, the preparation of waterborne epoxy resin emulsion has small particle size and good stability. At the same time, when molar ratio of epoxy resin and diethylenetriamine was 1:1, reaction temperature of 80°C, the performance of waterborne epoxy curing agent is well.

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Cold-Cured Bisphenolic Epoxy Adhesive Filled with Low Amounts of CaCO3: Effect of the Filler on the Durability to Aqueous Environments

Materials ◽

10.3390/ma14061324 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1324

Author(s):

Anna Rudawska ◽

Mariaenrica Frigione

Keyword(s):

Mechanical Properties ◽

Mannich Base ◽

Filler Content ◽

Epoxy Adhesive ◽

Compressive Modulus ◽

Curing Agent ◽

Aqueous Environments ◽

Curing Agents ◽

Effects Of Aging ◽

Manova Analysis

The effects of aging exposures to three non-saline aqueous environments on the compressive mechanical properties of a calcium carbonate-filled bisphenolic epoxy adhesive, cold-cured with the addition of two curing agents suitable for the cure at ambient temperature (i.e., Mannich base and triethylenetetramine), were assessed. The amount of the added filler (CaCO3) varied from 1 to 3 g per 100 g of resin; the immersion times in each of the selected medium varied from 1 to 10 months. It was found that the mechanical properties measured in compression mode on cylindrical specimens of unfilled and CaCO3-loaded epoxy were scarcely influenced by the kind of curing agent employed; only the compressive modulus was limitedly affected by this parameter. Referring to the behavior when aged in water, the CaCO3-filled epoxies displayed noticeable growths in modulus, small reductions in strength, and limited variations in strain, with a certain influence of the exposure time, especially when comparing the properties at the lowest time with those at medium–long times. On the basis of the results of statistical MANOVA analysis, it can be concluded that among the compositional factors (i.e., the type of curing agent employed to cure the epoxy compounds and the micro-filler content), only the amount of CaCO3 filler significantly affects the compressive modulus.

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Effect of Curing Agent on the Curing Behavior and Joint Strength of Epoxy Adhesive

Journal of Welding and Joining ◽

10.5781/kwjs.2011.29.4.416 ◽

2011 ◽

Vol 29 (4) ◽

pp. 54-60 ◽

Cited By ~ 2

Author(s):

Min-Su Kim ◽

Hae-Yeon Kim ◽

Se-Hoon Yoo ◽

Jong-Hoon Kim ◽

Jun-Ki Kim

Keyword(s):

Joint Strength ◽

Epoxy Adhesive ◽

Curing Agent ◽

Curing Behavior

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Mechanical Properties of Selected Epoxy Adhesive and Adhesive Joints of Steel Sheets

Applied Mechanics ◽

10.3390/applmech2010007 ◽

2021 ◽

Vol 2 (1) ◽

pp. 108-126

Author(s):

Anna Rudawska

Keyword(s):

Mechanical Properties ◽

Epoxy Resin ◽

Experimental Tests ◽

Epoxy Adhesive ◽

Adhesive Joints ◽

Stoichiometric Ratio ◽

Curing Agent ◽

Steel Sheets ◽

Epoxy Adhesives ◽

Strength Tests

The article presents the issues of the mechanical properties of epoxy adhesives and the adhesive joints strength of steel sheets which were made using the epoxy adhesives. The aim of the paper is to study the mechanical properties of epoxy adhesive of different epoxy resin/curing agent ratios (within and above the recommended stoichiometric ratio) and their effect on mechanical properties of adhesive joints of steel sheets. In experimental tests three types of epoxy adhesives, containing a low molecular weight epoxy resin based on bisphenol A and polyamide curing agent, were used. A single-lap adhesive joint type of stainless-steel sheets was also applied. Two types of strength test were used: the compressive strength tests (DIN EN 196-1) for epoxy adhesive samples and the shear strength tests (DIN EN 1465) for adhesive joints. Both the analysis of the strength results of the samples of epoxy adhesive and adhesive joints as well as the failure analysis was carried out. On the basis of the results of strength tests it can be stated that the greatest deformation occurred for the samples of epoxy adhesive containing the modified epoxy resin (epoxy number—0.40) and the polyamide curing agent, and the smallest for the samples of epoxy adhesive containing the basic epoxy resin (epoxy number—0.49–0.52) and the polyamide curing agent. The epoxy adhesives with a smaller amount of curing agent were characterized by higher strength. This applies to all analyzed epoxy resins. The same dependences were obtained for the strength of adhesive joints of steel sheets made of the analyzed epoxy adhesive.

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