Controlled preparation and properties of acrylic acid epoxy‐acrylate composite emulsion for self‐crosslinking coatings

Abstract

A stable epoxy‐acrylate composite latex was successfully prepared through emulsion polymerization of modified epoxy acrylic (EPAC) oligomer with acrylate monomer. The EPAC oligomer was obtained using active acrylic acid (AA) to react with epoxy resin. And by regulating the reaction degree of the active hydrogen of AA and epoxide group, there is the acquisition of terminal double bond that gives EPAC reactivity, together with the partial retention of the epoxide group that enables self‐crosslinking during film formation. The structural conformation of the oligomer was ascertained by Fourier transform infrared (FTIR) spectroscopy. The factors influencing the stability of the epoxy‐acrylate composite latex were investigated. The epoxy‐acrylate composite latex was the most stable when methyl acrylic acid was 1.5 wt% and modified EPAC oligomer was 15 wt% of the total monomer weight. The morphology and property of the composite latex films were characterized by scanning electron microscopy, transmission electron microscopy (TEM), and temperature‐modulated differential scanning calorimetry (TOPEM‐DSC). The results confirm that there is successful emulsion copolymerization between modified EPAC oligomer and acrylate monomer. TEM show that the particles of epoxy‐acrylate composite have a core‐shell structure, and there is no free epoxy resin. The FTIR and TOPEM‐DSC results reveal that the copolymer emulsion possesses self‐crosslinking ability. During film formation, self‐crosslinking reaction occurs between epoxide groups with carboxyl groups, giving exothermal phenomena. The thermal stability as well as the corrosion resistance of the films was analyzed. The results show outstanding thermal stability as well as corrosion resistance attributable to the crosslinking reticulation structure. It is envisaged that the epoxy‐acrylate composite latex has great potential in the development of high‐performance aqueous coatings.

Photo-and Heat-Induced Dismantlable Adhesion Interfaces Prepared by Layer-by-Layer Deposition

“…Considering the organization of the molecular layers, amine groups and carboxyl groups were present at the outermost surface of APS layer and APS/Di9AC layer, respectively. It is known that amine groups are generally used for curing of epoxy resins, and esterification-induced cross-linking can take place between epoxide and carboxyl groups. − Thus, it is reasonable that covalent bonds are created at the adhesion interface by these molecular layers. Note that the molecular layer prepared by layer-by-layer deposition includes acid–base interaction between the stacked molecules.…”

Enhanced Anticorrosion Properties through Structured Particle Design of Waterborne Epoxy-Styrene-Acrylate Composite Emulsion

“…Acrylic-modified epoxy resin containing vinyl groups, and with partial retention of epoxy groups, was synthesized by the esterification of epoxy resin with acrylic acid following the typical process detailed elsewhere [16]. The modified epoxy resin was synthesized by the reaction of E-44 with AA monomers at a molar ratio of 1:1, as depicted in Figure 1.…”

“…More recently, our group synthesized a new epoxy acrylic oligomer containing a vinyl group through an epoxy resin reaction with acrylic acid in a controlled manner, where epoxide groups were partially retained. This led to the successful generation of an epoxy-acrylate composite emulsion [16]. Although the oligomeric monomer was placed in the core of a core-shell particle, where the shell was an acrylic polymer, the epoxide in the oligomeric monomer survived the reaction with carboxylic functional monomers in the shell.…”

Synthesis and Application of Reactive Acrylic Latexes: Effect of Particle Morphology

“…Acrylic polymer dispersions bearing reactive epoxy groups are an important class of functional polymers that are used in various industrial applications such as paints, adhesives, coatings, sealants, etc. [ 2 , 11 , 12 , 13 ]. The oxirane ring of the epoxy group can provide a wide range of modifications due to its reactivity with carboxyl, hydroxyl, and amine groups present in the coating and substrate.…”