摘要
Abstract
Using trimellitic anhydride,adipic acid and neopentyl glycol as raw materials,along with dibutyl tin dilaurate as catalyst,the unmodified water-based polyester resin was synthesized through a xylene reflux dehydration polycondensation reaction process.The water-based polyester resins modified with polycaprolactone diol and hydrophobic functional monomer(TWG-01)respectively,were prepared utilizing the same polycondensation reaction methodology.The application of these water-based polyester resins in white topcoats for color steel plate was investigated.Experimental results indicated that in the absence of dispersants or co-solvents,the white topcoat for colour steel plates,prepared from unmodified water-based polyester resin,exhibited poor storage stability,and the coating film gloss is only 38%.In contrast,the white topcoat for color steel plate prepared from hydrophobically modified water-based polyester,exhibited good storage stability,and the cured coating film achieved a film gloss of up to 90%.A cross-cut test rating of 0,a pencil hardness of 3H,a T-bend rating of 1T,a reverse impact resistance of 100 kg·cm,and a cup indentation test result of 7.0 mm.These performance indexes of the coating film matched that of the pre-coated coil coating standard(HG/T 3830-2022).Furthermore,scanning electron microscopy(SEM)analysis revealed that the gloss of the coating film is closely related to dispersion of pigment particles within the film,and the traditional polyacrylate dispersant can lead to aggregation of pigment particles in the coating film.关键词
水性聚酯树脂/彩钢板涂料/改性Key words
Waterborne polyester resin/Color steel plate coating/Modification分类
化学化工
