Preparation and Application of Waterborne Epoxy Ester Resins Based on Renewable Fatty Acids

0 Preface

The production and use of traditional solvent-based coatings generate volatile organic compounds (VOCs), which cause environmental pollution and present safety risks during production, storage, and u.

There have been successful application cases of applying renewable resources in the field of waterborne industrial coatings, mainly including two categories: waterborne alkyd coatings and waterborne epoxy ester coatin.

In this paper, an environmentally friendly water-based epoxy ester resin was prepared by esterification reaction and graft polymerization using renewable fatty acids, epoxy resins, and vinyl monomers as raw materia.

1 Experimental part

1 Preparation of water-based epoxy ester resin

Put the fatty acid, epoxy resin, catalyst, and dehydration solvent in metered proportions into the reactor in batches, slowly heat up to 200 °C at a rate of 10 °C/h under a nitrogen atmosphere, and react at a constant temperature until the acid value is less than 5 mg KOH.

The above epoxy ester intermediate is heated to 120~130 °C, the mixture of vinyl monomer mixture and initiator is added dropwise at a constant speed, and it is dripped for 3~4 h, and the reaction is kept at 120~130 °C for 1~2 h; The initiator mixture was added dropwise at 120~130 °C, and the dropping was completed within 1.

Figure 1 Process route for the preparation of water-based epoxy esters

2 Preparation of aqueous epoxy ester dispersion

Weigh a quantitative amount of the water-based epoxy ester resin, add the drier and pH adjuster in the metered ratio in turn, and after stirring evenly, slowly add the deionized water in the metered ratio while stirring to prepare the water-based epoxy ester dispersi.

3 Preparation of waterborne epoxy ester coatings

According to the reference formula in Table 1, the preparation process of the water-based epoxy ester coating is as follows: (1) After mixing the raw materials .

Table 1 Reference formula of water-based epoxy ester coating

2 Results and discussion

1 Infrared spectrum

Figure 2 is an infrared spectrum of an epoxy ester intermediate and a water-based epoxy ester res.

Figure 2 Infrared spectrum

2 Molecular weight and its distribution

In this study, gel permeation chromatography was used to determine the molecular weight and distribution of epoxy ester intermediates and water-based epoxy ester resi.

Figure 3 Molecular weight and distribution of epoxy ester intermediate and waterborne epoxy ester resin

Table 2 Molecular weight and distribution of epoxy ester intermediate and waterborne epoxy ester resin

3 Resin viscosity

At present, water-based epoxy ester resin products are usually supplied in the state of resin without water in practical applications, and coating manufacturers add water to disperse and emulsify as needed in practical applicatio.

Table 3 Viscosity of epoxy ester intermediate and waterborne epoxy ester resin

3 Coating properties

The self-made water-based epoxy ester resin is used as the film-forming material, the water-based resin and the dispersant are used to grind the pigment and filler together, and the water-based paint auxiliary is mixed to prepare the one-component water-based epoxy ester coati.

Table 4 Properties of waterborne epoxy ester coatings

3 Conclusion

Using fatty acid, epoxy resin and vinyl monomer as main raw materials, waterborne epoxy ester resin was synthesized through esterification reaction and graft polymerization, and one-component waterborne epoxy ester coating was prepared with self-made waterborne epoxy ester res.

(1) The epoxy ester intermediate was obtained by esterification, and the water-based epoxy ester resin was obtained by copolymerizing it with vinyl monom.

(2) Emulsifying the water-based epoxy ester resin to obtain a water-based epoxy ester dispersion, the average particle size Dx (50) of which is 0585 μm, and the particle size distribution is unifo.

(3) Using the prepared water-based epoxy ester resin as a film-forming material to prepare a one-component water-based epoxy ester coating, the coating has excellent comprehensive properties and is suitable for medium and light industrial protection fiel.

References (omitted)

Author | Xu Fei, Zhang Hanqing, Hu Zhong, e.

(CNOOC Changzhou Coating Chemical Research Institute .

, L.

, National Coating Engineering Technology Research Center, Changzhou, Jiangsu 213016)